Pramil Singh - Academia.edu (original) (raw)

Papers by Pramil Singh

Research paper thumbnail of Dietary patterns of children aged 0‐59 months in Ukambani region of Kenya

Research paper thumbnail of The Design, Development and Evaluation of the Vegetarian Lifestyle Index on Dietary Patterns among Vegetarians and Non-Vegetarians

Nutrients, Jan 26, 2018

Traditionally, healthful diets and lifestyles have been examined only in relation to single nutri... more Traditionally, healthful diets and lifestyles have been examined only in relation to single nutrients, foods, or food groups in terms of dietary exposure. An alternative approach is to conceptualize an index based on vegetarian food pyramid guidelines as a measure of overall diet and lifestyle quality. Our objectives were to: (1) develop the Vegetarian Lifestyle Index (VLI); and (2) evaluate adherence to the Vegetarian Food Guide Pyramid (VFGP) among a low-risk population of Adventists. The index was based on the operationalization of 14 dietary and lifestyle components. All components were equally weighted. Higher score reflected greater adherence to the VFGP. The analytic sample ( = 90,057) comprised 47.7% non-vegetarians, 5.6% semi-, 10.1% pesco-, and 29.0% lacto-ovo-vegetarians, and 7.7% vegans, of which 1.1% were current smokers and 9.9% were alcohol consumers. Population mean VLI score was 7.43 (SD = 1.75) ranging from 1 to 12.5. Non-vegetarians (6.14; 95% confidence interval ...

Research paper thumbnail of Simulation Study of the Effect of the Early Mortality Exclusion on Confounding of the Exposure-Mortality Relation by Preexisting Disease

American Journal of Epidemiology, 2001

The authors conducted a simulation study to evaluate whether exclusion of the early mortality (de... more The authors conducted a simulation study to evaluate whether exclusion of the early mortality (deaths occurring during a prespecified period immediately after baseline) reduces confounding of the exposuremortality relation by preexisting disease. The simulation specified an exposure that decreased mortality risk in the absence of confounding and then introduced confounding by preexisting disease that biased the "true" protective effect of exposure towards greater risk. In 2,000 cohorts, exclusion of the early mortality (deaths occurring during the first 25 months of a 60-month follow-up period) did not alter the mean hazard ratio for exposure under conditions of confounding by preexisting disease that produced a constant, threefold increase in mortality risk during follow-up (the mean hazard ratio was 1.72 for all subjects and 1.72 after exclusion of the early mortality). However, when the authors specified confounding by preexisting disease which produced a threefold increase in mortality risk that attenuated over time, exclusion of the early mortality consistently identified the "true" protective effect of exposure (the mean hazard ratio was 1.07 for all subjects and 0.31 after exclusion of the early mortality). Thus, under conditions of confounding by preexisting disease which produces an increase in mortality risk that attenuates over time-an effect that does have empirical support-the early mortality exclusion can be very effective in revealing the "true" exposure-mortality relation.

Research paper thumbnail of Village Health Workers Improve Child Health: The Jamkhed, India Experience

OBJECTIVE: To assess the effect of the three-decade old Comprehensive Rural Health Project (CRHP)... more OBJECTIVE: To assess the effect of the three-decade old Comprehensive Rural Health Project (CRHP) on morbidity, mortality, immunization rates, and health care utilization among children under 5 years of age in Jamkhed, Central India. METHODS: We conducted a cross-sectional survey of a stratified, cluster sample of 879 children (under-fives) in 15 Jamkhed villages served by CRHP. CRHP has a three-tiered primary health care model that comprises a tertiary care facility, a mobile health program supporting 30 subcenters, and community-based health workers. FINDINGS: We found a prevalence of diarrhea [6.4%, 95% CI: 4.0%-8.8%], measles [2.3%, 95% CI: 0%-5.6%], tuberculosis [0.3%, 95% CI: 0%-0.8%], bronchopneumonia [0.1%, 95% CI: 0-0.3%], and no cases of poliomyelitis, pertussis, diphtheria, and tetanus among under-fives. Malnutrition (using WHO criteria) was less evident in infants [mean Z-score: -0.8] compared to children aged 1-5 years [mean Z-scores: -1.6 to -1.8]. The child Internatio...

Research paper thumbnail of Microbial contamination in the communal-use Lao tobacco waterpipe

International Health, 2020

BackgroundThe use of the Asian tobacco waterpipe (TWP) in the Lao People's Democratic Republi... more BackgroundThe use of the Asian tobacco waterpipe (TWP) in the Lao People's Democratic Republic represents a potential communal source of infectious disease. This practice of smoking can lead to weakened defences of a smoker's respiratory epithelium, making the smoker vulnerable to respiratory diseases such as coronavirus disease 2019, tuberculosis and others.MethodsThis study evaluated the water quality and hygiene factors among 43 smokers of five villages in rural Luang Namtha Province. Water samples were collected from participant's TWPs and assessed for the presence of Escherichia coli, coliforms and aerobic plate count (APC) bacteria using the 3M Petrifilm.ResultsThe microbial indicator testing results were 95% positive for the APC, 38% positive for coliforms and 17% positive for the E. coli indicator. The concentrations were highest for the APC, with an average of 106 colony forming units (cfu)/ml, followed by coliforms with <100 cfu/ml and lowest for E. coli wit...

Research paper thumbnail of Air Pollution in a Nationally Representative Sample: Findings from the National Adult Tobacco Survey of Lao PDR

International Journal of Environmental Research and Public Health, 2019

In Southeast Asia, household air pollution (HAP) from solid fuel use is the leading cause of disa... more In Southeast Asia, household air pollution (HAP) from solid fuel use is the leading cause of disability-adjusted life years (DALYs), a risk which is compounded by exposure to other sources of indoor and outdoor air pollution including secondhand tobacco smoke (SHS). The purpose of this study was to measure the individual and combined prevalence of exposure to household and community sources of air pollution in a national sample of adults in Lao PDR. We analyzed data from the 2012 National Adult Tobacco Survey (NATSL) of Lao PDR—a multi-stage stratified cluster sample of 9706 subjects from 2822 households located in all 17 provinces. Our findings indicate a high prevalence of exposure to household air pollution from cooking fires (78%) and SHS exposure in the home (74.5%). More than a third (32.8%) reported exposure to both inside the home. Exposure to outdoor sources of smoke from cooking, trash, and crop fires was substantial (30.1% to 56.0%). The aggregation of exposures from mult...

Research paper thumbnail of Smoked Tobacco, Air Pollution, and Tuberculosis in Lao PDR: Findings from a National Sample

International Journal of Environmental Research and Public Health, 2019

In 2017, more than half of the global burden of incident tuberculosis (TB) came from the Western ... more In 2017, more than half of the global burden of incident tuberculosis (TB) came from the Western Pacific region. In Lao People’s Democratic Republic (PDR), the high rates of tobacco use and use of polluting biomass fuels for cooking (e.g., wood, charcoal, crop waste, dung) represent significant risk factors for TB. The purpose of this study was to determine the association between self-reported (1) smoking and TB; and (2) exposure to air pollution (from both cooking fires and environmental tobacco smoke) and TB among adults in Lao PDR. We analyzed data from the 2012 National Adult Tobacco Survey (NATSL) of Lao PDR—a multi-stage stratified cluster sample of 9706 subjects from 2822 households located in all 17 provinces. Utilizing a nationally representative sample and inferential, multivariable methods, we observed a significant increase in odds of self-reported TB among those who smoked tobacco (OR = 1.73, 95% CI = (1.00 to 2.98)). Larger multivariable models identified independent ...

Research paper thumbnail of Exploring Demographic and Substance Use Correlates of Hookah Use in a Sample of Southern California Community College Students

Californian Journal of Health Promotion, 2015

Background and Purpose: Hookah smoking is a growing young adult phenomenon, particularly among co... more Background and Purpose: Hookah smoking is a growing young adult phenomenon, particularly among college students. Many users feel that it is safer than other tobacco products, although its health threats are well documented. Little is known about hookah use rates in community colleges that are attended by nearly half of all US college students. This study examined hookah use in a diverse convenience sample of students attending two southern California community colleges. Methods: In fall 2011, a crosssectional, in-classroom survey was administered to 1,207 students. A series of fully adjusted multivariate logistic regressions were conducted to explore demographic, other substance use, and attitudinal correlates of lifetime and current hookah use. Results: Lifetime hookah use (56%) was higher than lifetime cigarette use (49%). Gender and personal socioeconomic status were not related to hookah use. Current use (10.8%) was associated with current use of alcohol, cigars, and cigarettes....

Research paper thumbnail of Hookah waterpipe: More prevalent than the cigarette among community college students

Results from the first ever community college study on waterpipe use (n=1,207) in fall 2011 at tw... more Results from the first ever community college study on waterpipe use (n=1,207) in fall 2011 at two demographically diverse schools in Southern California found use in the higher range of the collegiate literature (seventeen peer-reviewed studies; all from four-year schools, 2004-2011) - 55.5% reported ever using the waterpipe, and more than one in three (34.1%) used it in the previous year. More students have experimented with the waterpipe than ever smoked a cigarette, 48.8%. Current use, 10.8%, is associated with current alcohol (AOR=2.8, p<.001), current cigar (AOR=2.5, p<.01) and current cigarette use (AOR=1.8, p<.05) as well as female binge drinking (AOR=1.8, p=<.05). Compared to African-Americans, Whites are 2.9 times (p<.05) more likely to be current users. Current marijuana, illegal drug, and smokeless tobacco use are not associated with any measure of waterpipe use and there are also no gender or economic (financial aid, first generation, and hours worked per...

Research paper thumbnail of Environmental exposures, lung function, and respiratory health in rural Lao PDR

The Southeast Asian journal of tropical medicine and public health, 2014

Although the individual contributions of smoked tobacco and indoor air pollution have been identi... more Although the individual contributions of smoked tobacco and indoor air pollution have been identified, there are very few studies that have characterized and measured the effects of inhaled particles from a wide range of personal, household, and community practices common in rural Asia. The objective of our study was to examine the association between environmental inhaled exposures and lung function among rural males of Lao PDR. In a sample of 92 males from rural Lao PDR, study subjects completed a survey on household exposures, a physical exam, and the following measures of lung function: FEV1, FVC, and the ratio of FEV1/FVC. Our findings were as follows: a) > 80% of the subjects were exposed to indoor cooking fires (wood fuel), animal handling, dust and dirt; b) 57.6% of subjects were in the impaired range (FEV1/FVC < 0.7); and c) animal handling was negatively associated (p < 0.03) with FEV1 and FVC. Among males in rural Lao PDR, we found a high prevalence of chronic ex...

Research paper thumbnail of Patterns of Maternal Tobacco Use Among Cambodian Women

Asia Pacific Journal of Public Health, 2013

Although current trends indicate that the rate of cigarette smoking tends to be low among women i... more Although current trends indicate that the rate of cigarette smoking tends to be low among women in the Western Pacific Region (<10%), recent epidemiologic data from South Asia (India, Bangladesh) and Southeast Asia (Cambodia, Vietnam, Indonesia, Malaysia) identify that a large proportion of women of reproductive age and older chew tobacco—often as part of a betel quid mixture that includes other potentially harmful ingredients (eg, areca nut). Our findings from currently pregnant women identified during a nationwide survey of adult tobacco use in Cambodia indicate that 13.0% (95% confidence interval [CI] = 8% to 17%) were current users of smoked or smokeless (in the form of a betel quid) tobacco. Most pregnant women who used tobacco indicated that their habit was either initiated (29.1%; 95% CI = 16.3-46.3) or increased (33.7%; 95% CI = 18.3-53.5) during pregnancy. Pregnancy-related symptoms such as morning sickness were reported as the reason for more than half (54.9%; 95% CI = ...

Research paper thumbnail of Reliability of Meat, Fish, Dairy, and Egg Intake Over a 33-Year Interval in Adventist Health Study 2

Nutrition and Cancer, 2014

We studied Adventist Health Study 2 (AHS-2) cohort members to determine the reliability of long-t... more We studied Adventist Health Study 2 (AHS-2) cohort members to determine the reliability of long-term recall of adult dietary intake that occurred 33 years ago. Establishing the reliability of these measures supports studies of how dietary exposure across the life course affects risk of cancer and other noncommunicable disease outcomes. Among 1816 AHS-2 cohort members, we conducted a statistical comparison of long-term recall of meat, fish, dairy, and eggs at AHS-2 baseline with their report of current diet 33 years before AHS-2 baseline at an age of 30-60 years. Major findings are as follows: 1) a high correlation for frequency of red meat (R = 0.71), poultry (R = 0.67), and fish (R = 0.60); lower correlations for dairy (R = 0.19) and eggs (R = 0.28); 2) good concordance for dichotomous measures of red meat [

Research paper thumbnail of Cigarette smoking and tuberculosis in Cambodia: findings from a national sample

Tobacco Induced Diseases, 2013

Background: Cambodia has very high rates of tuberculosis and smoked tobacco use among adults. Eff... more Background: Cambodia has very high rates of tuberculosis and smoked tobacco use among adults. Efforts to control both tobacco use and tuberculosis in Cambodia need to be informed by nationally representative data. Our objective is to examine the relation between daily cigarette smoking and lifetime tuberculosis (TB) history in a national sample of adults in Cambodia. Methods: In 2011, a multi-stage, cluster sample of 15,615 adults (ages 15 years and older) from all regions of Cambodia were administered the Global Adult Tobacco Survey by interviewers from the National Institute of Statistics of Cambodia. Results: Our findings include: 1) among daily smokers, a significant positive relation between TB and number of cigarettes smoked per day (OR = 1.70 [95% CI 1.01, 2.87]) and pack-years of smoking (OR = 1.53 [95% CI 1.05, 2.25]) 2) a non-significant 58% increase in odds of ever having being diagnosed with TB among men who smoked manufactured cigarettes (OR = 1.58 [95% CI 0.97, 2.58]). Conclusion: In Cambodia, manufactured cigarette smoking was associated with lifetime TB infection and the association was most evident among the heaviest smokers (> 1 pack per day, > 30 pack years).

Research paper thumbnail of Relative Validity of a Food Frequency Questionnaire Used to Assess Food Intake During a Dietary Intervention Study

Nutrition and Cancer, 2008

To develop a cost-effective alternative for evaluating dietary intake in large-scale intervention... more To develop a cost-effective alternative for evaluating dietary intake in large-scale intervention trials of cancer and cardiovascular disease outcomes, we designed and validated a semiquantitative food frequency questionnaire (FFQ). We collected 6 to 8 of the 24-hr dietary recalls from 87 adults (ages 30-72 yr) who were randomly assigned to a walnut-supplemented diet or a control diet in a 6-mo dietary intervention trial. Relative validity of a 171-item FFQ in assessing intake of selected foods and the prescribed intervention (intake ≥25 g/day or intake <2 g of walnuts) was determined using 24-h dietary recalls as the reference. De-attenuated correlations between FFQ and dietary recalls were .82 for walnuts, .80 for fruits, .79 for grains, .77 for vegetables, .63 for water, .44 for sweets, and .36 for dairy/eggs. High within-person variation did not allow de-attenuation for the remaining foods, but uncorrected correlations were high (>.7) for the beverage variables. The FFQ correctly classified 86 out of 87 subjects in the 2 prescribed intervention groups. The FFQ can provide an accurate measure of a food-based intervention (i.e., walnut supplementation) in a trial setting and can also accurately estimate a number of other food groups consumed during the trial.

Research paper thumbnail of Waterpipe smoking and nicotine exposure: A review of the current evidence

Nicotine & Tobacco Research, 2007

The waterpipe, also known as shisha, hookah, narghile, goza, and hubble bubble, has long been use... more The waterpipe, also known as shisha, hookah, narghile, goza, and hubble bubble, has long been used for tobacco consumption in the Middle East, India, and parts of Asia, and more recently has been introduced into the smokeless tobacco market in western nations. We reviewed the published literature on waterpipe use to estimate daily nicotine exposure among adult waterpipe smokers. We identified six recent studies that measured the nicotine or cotinine levels associated with waterpipe smoking in four countries (Lebanon, Jordan, Kuwait, and India). Four of these studies directly measured nicotine or cotinine levels in human subjects. The remaining two studies used smoking machines to measure the nicotine yield in smoking condensate produced by the waterpipe. Meta-analysis of the human data indicated that daily use of the waterpipe produced a 24-hr urinary cotinine level of 0.785 µg/ml (95% CI = 0.578-0.991 µg/ml), a nicotine absorption rate equivalent to smoking 10 cigarettes/day (95% CI = 7-13 cigarettes/day). Even among subjects who were not daily waterpipe smokers, a single session of waterpipe use produced a urinary cotinine level that was equivalent to smoking two cigarettes in one day. Estimates of the nicotine produced by waterpipe use can vary because of burn temperature, type of tobacco, waterpipe design, individual smoking pattern, and duration of the waterpipe smoking habit. Our quantitative synthesis of the limited human data from four nations indicates that daily use of waterpipes produces nicotine absorption of a magnitude similar to that produced by daily cigarette use.

Research paper thumbnail of The effect of menopause on the relation between weight gain and mortality among women

Menopause, 2001

Objective: To examine the effect of menopause on the relation between weight gain and all-cause m... more Objective: To examine the effect of menopause on the relation between weight gain and all-cause mortality. Design: Prospective cohort study of 6,030 adults (ages 25-82 years) who never smoked cigarettes, had no history of coronary heart disease, cancer, or stroke, and were enrolled in a 29-year follow-up in which anthropometric data were given at baseline and at 17 years after baseline. Results: Weight gain that occurred over a 17-year interval (baseline to 17 years after baseline) increased the mortality risk of men and middle-aged women, but decreased the mortality risk of older women. Further study of the women revealed that a strong protective effect of weight gains was only evident among the leanest (Յ25 kg/m 2) postmenopausal women. Specifically, weight gains of 10 kg or more (median = 13 kg) produced an almost threefold decrease in mortality risk among the leanest (Յ25 kg/m 2) postmenopausal women [hazard ratio (HR) (95% confidence interval; CI) = 0.35 (0.13, 0.96)], but did not confer strong protection for heavier (>25 kg/m 2) postmenopausal women [HR (95% CI) = 0.81 (0.41, 1.58)] or for premenopausal women [HR (95% CI) = 1.05 (0.49, 2.25) for Յ25 kg/m 2 , 0.95 (0.38, 2.37) for >25 kg/m 2 ]. We found that the protective effect of weight gain among the leanest postmenopausal women was primarily due to a more than threefold decrease in cardiovascular disease mortality risk. One possible explanation for these findings is that weight gain increases the level of adipose-tissue-derived estrogen among lean postmenopausal women. Conclusion: Moderate menopausal weight gain may be well tolerated in lean women.

Research paper thumbnail of Does Excess Body Fat Maintained After the Seventh Decade Decrease Life Expectancy?

Journal of the American Geriatrics Society, 2011

To determine whether the attenuation in risk of death due to excess body fat seen in most studies... more To determine whether the attenuation in risk of death due to excess body fat seen in most studies of older adults may be due to confounding, the relationship between adiposity and mortality was examined in adults who never smoked, were free of major chronic diseases, and maintained stable weight over long periods. Prospective cohort study. The Adventist Health Study and Adventist Mortality Study in California. Six thousand thirty adults aged 25 to 82 who had never smoked and had no history of coronary heart disease, cancer, or stroke. During 29 years of follow-up, anthropometric data were collected at baseline and 17 years later, and mortality surveillance continued for 12 years thereafter. Data were analyzed using survival analysis with attained age as the time variable. Instantaneous hazard plots indicated that men with a body mass index (BMI) greater than 22.3 kg/m2 and women with a BMI greater than 27.4 kg/m2 had a greater mortality risk through the ninth decade than those with lower BMI. For men aged 75 to 99 who maintained stable body weight, a BMI greater than 22.3 kg/m2 was associated with a 3.7-year (95% confidence interval (CI)=1.1-6.3) shorter life expectancy and significantly greater mortality (hazard ratio (HR)=1.88, 95% CI=1.16-3.04, for BMI=22.3-27.3 kg/m2; HR=2.00, 95% CI=1.01-3.97 for BMI&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;27.3 kg/m2; reference, BMI≤22.3 kg/m2). For women aged 75 to 99 who maintained stable body weight, a BMI greater than 27.4 kg/m2 was associated with a 2.1-year (95% CI=0.5-3.8) shorter life expectancy and significantly greater mortality (HR=1.12, 95% CI=0.80-1.58 for BMI&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;20.6 kg/m2; HR=1.41, 95% CI=1.05-1.89 for BMI&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;27.4 kg/m2; reference, BMI 20.6-27.4 kg/m2). Excess body fat maintained after the seventh decade decreases life expectancy but appears to be less lethal in women.

Research paper thumbnail of Betel quid use in relation to infectious disease outcomes in Cambodia

International Journal of Infectious Diseases, 2012

Betel quid use involves the chewing of areca nut (Areca catechu L. (Arecaceae)), betel leaf (Pipe... more Betel quid use involves the chewing of areca nut (Areca catechu L. (Arecaceae)), betel leaf (Piper betle L. (Piperaceae)), slaked lime (calcium hydroxide), and tobacco, and is practiced by 600 million persons in Asia, South Asia, and Southeast Asia, 1-3 and also among migrants from those regions living in Western nations. 4 Largescale prospective cohort studies in India and Taiwan have shown that betel quid use in women and men is associated with a 20-30% increase in the all-cause mortality rate. 5,6 Some of the chronic diseases underlying this trend include (1) a well-known association with oral cancer, oral leukoplakia, and submucous fibrosis, which have primarily been attributed to the formation of carcinogenic N-nitroso compounds produced by the quid, 7 and (2) a growing body of evidence of a link with cardiovascular disease and diabetes. 8-10 Although a relationship between betel quid and periodontal infections has been reported, 11 there is a paucity of data investigating a link between betel quid and infectious, communicable disease. Qualitative and quantitative data are emerging from several nations indicating that the use of betel quid may be an integral part of cultural, familial, and traditional medicine practices. 3,4,12,13 Specifically, the betel quid ingredients are known throughout Asia and South Asia for their medicinal effects as a stimulant, a digestive aid (specifically for the relief of morning sickness during pregnancy), 12 an antiseptic, a de-worming agent, a pain reliever, and for the treatment of infectious disease. 13 During a large-scale prevalence study of tobacco use in Cambodia (N = 13 988) 12,14 in 2005-2006, we found that (1) about half the older women (>48 years) are habitual betel quid users, (2) one out of five women started the habit during pregnancy in response to morning sickness, 15 and (3) by occupation the highest prevalence of chewing tobacco was among midwives (67.9%) and traditional healers (47.1%). These data raise the possibility that traditional medicine practices are influencing the initiation and use of the betel quid in Cambodia. In the current analyses of this national sample of 13 988 adults in Cambodia, 12 our aims were (1) to examine the association between habitual betel quid use and specific infectious diseases (HIV/AIDS, tuberculosis, dengue fever, typhoid), and (2) to examine the association between betel quid use and the use of traditional medicine services (i.e., traditional healer, traditional birth attendant,

Research paper thumbnail of Mixed Methods Pilot Study of Sharing Behaviors among Waterpipe Smokers of Rural Lao PDR: Implications for Infectious Disease Transmission

International Journal of Environmental Research and Public Health, 2013

To date, the sharing behaviors associated with the homemade tobacco waterpipe used in rural areas... more To date, the sharing behaviors associated with the homemade tobacco waterpipe used in rural areas of the Western Pacific Region have not been studied. Evidence from studies of manufactured waterpipes raises the possibility of infectious disease transmission due to waterpipe sharing. The objective of our pilot study in rural Lao People's Democratic Republic (PDR) was to identify and measure the prevalence of waterpipe sharing behaviors. We first conducted ethnographic studies to investigate waterpipe-smoking behaviors. These findings were then used to develop an interviewer-administered household survey that was used in a sampling of waterpipe smokers from three villages of the Luang Namtha OPEN ACCESS province of Lao PDR (n = 43). Sampled waterpipe smokers were predominantly male (90.7%), older (mean age 49, SD 13.79), married (95.4%), farmers (78.6%), and had completed no primary education. Pipes were primarily made from bamboo (92.9%). Almost all (97.6%) smokers were willing to share their pipe with others. At the last time they smoked, smokers shared a pipe with at least one other person (1.2 ± 0.5 persons). During the past week, they had shared a pipe with five other persons (5.2 ± 3.8 persons). The high prevalence of sharing behaviors among waterpipe smokers in rural Southeast Asia raises the possibility that this behavior provides important and unmeasured social network pathways for the transmission of infectious agents.

Research paper thumbnail of Dietary Risk Factors for Ovarian Cancer: The Adventist Health Study (United States)

Cancer Causes & Control, 2006

Few prospective studies have reported dietary risk factors for ovarian cancer. A total of 71 hist... more Few prospective studies have reported dietary risk factors for ovarian cancer. A total of 71 histologically confirmed epithelial ovarian cancers occurred among 13,281 non-Hispanic white California Seventh-day Adventist women during follow-up. Participants were part of the Adventist Health Study (AHS) and had no history of cancer or hysterectomy at baseline in 1976 when they completed a detailed lifestyle questionnaire including a dietary assessment. The association of dietary variables with either all ovarian cancer cases or postmenopausal cases was tested using proportional hazards regression with adjustment for age and other covariates. The strongest hazardous risk factor associations among the food variables were found for meat intake with a risk ratio (RR) of 2.42 for intake &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; or = 1 time/week versus no meat (p for trend = 0.006), and cheese intake with a RR of 2.02 for intake of &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; 2 time/week versus &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 1 per week (p for trend = 0.10), both of these being in postmenopausal cases. We found significantly reduced risk of all ovarian cancer with higher tomato consumption (RR = 0.32) comparing intakes &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; or = five times/week versus never to &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 1 time/week (p for trend = 0.002), and also with higher fruit consumption (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01). A weak protective association was found with low fat, but not whole milk. Little confounding was observed between these foods.

Research paper thumbnail of Dietary patterns of children aged 0‐59 months in Ukambani region of Kenya

Research paper thumbnail of The Design, Development and Evaluation of the Vegetarian Lifestyle Index on Dietary Patterns among Vegetarians and Non-Vegetarians

Nutrients, Jan 26, 2018

Traditionally, healthful diets and lifestyles have been examined only in relation to single nutri... more Traditionally, healthful diets and lifestyles have been examined only in relation to single nutrients, foods, or food groups in terms of dietary exposure. An alternative approach is to conceptualize an index based on vegetarian food pyramid guidelines as a measure of overall diet and lifestyle quality. Our objectives were to: (1) develop the Vegetarian Lifestyle Index (VLI); and (2) evaluate adherence to the Vegetarian Food Guide Pyramid (VFGP) among a low-risk population of Adventists. The index was based on the operationalization of 14 dietary and lifestyle components. All components were equally weighted. Higher score reflected greater adherence to the VFGP. The analytic sample ( = 90,057) comprised 47.7% non-vegetarians, 5.6% semi-, 10.1% pesco-, and 29.0% lacto-ovo-vegetarians, and 7.7% vegans, of which 1.1% were current smokers and 9.9% were alcohol consumers. Population mean VLI score was 7.43 (SD = 1.75) ranging from 1 to 12.5. Non-vegetarians (6.14; 95% confidence interval ...

Research paper thumbnail of Simulation Study of the Effect of the Early Mortality Exclusion on Confounding of the Exposure-Mortality Relation by Preexisting Disease

American Journal of Epidemiology, 2001

The authors conducted a simulation study to evaluate whether exclusion of the early mortality (de... more The authors conducted a simulation study to evaluate whether exclusion of the early mortality (deaths occurring during a prespecified period immediately after baseline) reduces confounding of the exposuremortality relation by preexisting disease. The simulation specified an exposure that decreased mortality risk in the absence of confounding and then introduced confounding by preexisting disease that biased the "true" protective effect of exposure towards greater risk. In 2,000 cohorts, exclusion of the early mortality (deaths occurring during the first 25 months of a 60-month follow-up period) did not alter the mean hazard ratio for exposure under conditions of confounding by preexisting disease that produced a constant, threefold increase in mortality risk during follow-up (the mean hazard ratio was 1.72 for all subjects and 1.72 after exclusion of the early mortality). However, when the authors specified confounding by preexisting disease which produced a threefold increase in mortality risk that attenuated over time, exclusion of the early mortality consistently identified the "true" protective effect of exposure (the mean hazard ratio was 1.07 for all subjects and 0.31 after exclusion of the early mortality). Thus, under conditions of confounding by preexisting disease which produces an increase in mortality risk that attenuates over time-an effect that does have empirical support-the early mortality exclusion can be very effective in revealing the "true" exposure-mortality relation.

Research paper thumbnail of Village Health Workers Improve Child Health: The Jamkhed, India Experience

OBJECTIVE: To assess the effect of the three-decade old Comprehensive Rural Health Project (CRHP)... more OBJECTIVE: To assess the effect of the three-decade old Comprehensive Rural Health Project (CRHP) on morbidity, mortality, immunization rates, and health care utilization among children under 5 years of age in Jamkhed, Central India. METHODS: We conducted a cross-sectional survey of a stratified, cluster sample of 879 children (under-fives) in 15 Jamkhed villages served by CRHP. CRHP has a three-tiered primary health care model that comprises a tertiary care facility, a mobile health program supporting 30 subcenters, and community-based health workers. FINDINGS: We found a prevalence of diarrhea [6.4%, 95% CI: 4.0%-8.8%], measles [2.3%, 95% CI: 0%-5.6%], tuberculosis [0.3%, 95% CI: 0%-0.8%], bronchopneumonia [0.1%, 95% CI: 0-0.3%], and no cases of poliomyelitis, pertussis, diphtheria, and tetanus among under-fives. Malnutrition (using WHO criteria) was less evident in infants [mean Z-score: -0.8] compared to children aged 1-5 years [mean Z-scores: -1.6 to -1.8]. The child Internatio...

Research paper thumbnail of Microbial contamination in the communal-use Lao tobacco waterpipe

International Health, 2020

BackgroundThe use of the Asian tobacco waterpipe (TWP) in the Lao People's Democratic Republi... more BackgroundThe use of the Asian tobacco waterpipe (TWP) in the Lao People's Democratic Republic represents a potential communal source of infectious disease. This practice of smoking can lead to weakened defences of a smoker's respiratory epithelium, making the smoker vulnerable to respiratory diseases such as coronavirus disease 2019, tuberculosis and others.MethodsThis study evaluated the water quality and hygiene factors among 43 smokers of five villages in rural Luang Namtha Province. Water samples were collected from participant's TWPs and assessed for the presence of Escherichia coli, coliforms and aerobic plate count (APC) bacteria using the 3M Petrifilm.ResultsThe microbial indicator testing results were 95% positive for the APC, 38% positive for coliforms and 17% positive for the E. coli indicator. The concentrations were highest for the APC, with an average of 106 colony forming units (cfu)/ml, followed by coliforms with <100 cfu/ml and lowest for E. coli wit...

Research paper thumbnail of Air Pollution in a Nationally Representative Sample: Findings from the National Adult Tobacco Survey of Lao PDR

International Journal of Environmental Research and Public Health, 2019

In Southeast Asia, household air pollution (HAP) from solid fuel use is the leading cause of disa... more In Southeast Asia, household air pollution (HAP) from solid fuel use is the leading cause of disability-adjusted life years (DALYs), a risk which is compounded by exposure to other sources of indoor and outdoor air pollution including secondhand tobacco smoke (SHS). The purpose of this study was to measure the individual and combined prevalence of exposure to household and community sources of air pollution in a national sample of adults in Lao PDR. We analyzed data from the 2012 National Adult Tobacco Survey (NATSL) of Lao PDR—a multi-stage stratified cluster sample of 9706 subjects from 2822 households located in all 17 provinces. Our findings indicate a high prevalence of exposure to household air pollution from cooking fires (78%) and SHS exposure in the home (74.5%). More than a third (32.8%) reported exposure to both inside the home. Exposure to outdoor sources of smoke from cooking, trash, and crop fires was substantial (30.1% to 56.0%). The aggregation of exposures from mult...

Research paper thumbnail of Smoked Tobacco, Air Pollution, and Tuberculosis in Lao PDR: Findings from a National Sample

International Journal of Environmental Research and Public Health, 2019

In 2017, more than half of the global burden of incident tuberculosis (TB) came from the Western ... more In 2017, more than half of the global burden of incident tuberculosis (TB) came from the Western Pacific region. In Lao People’s Democratic Republic (PDR), the high rates of tobacco use and use of polluting biomass fuels for cooking (e.g., wood, charcoal, crop waste, dung) represent significant risk factors for TB. The purpose of this study was to determine the association between self-reported (1) smoking and TB; and (2) exposure to air pollution (from both cooking fires and environmental tobacco smoke) and TB among adults in Lao PDR. We analyzed data from the 2012 National Adult Tobacco Survey (NATSL) of Lao PDR—a multi-stage stratified cluster sample of 9706 subjects from 2822 households located in all 17 provinces. Utilizing a nationally representative sample and inferential, multivariable methods, we observed a significant increase in odds of self-reported TB among those who smoked tobacco (OR = 1.73, 95% CI = (1.00 to 2.98)). Larger multivariable models identified independent ...

Research paper thumbnail of Exploring Demographic and Substance Use Correlates of Hookah Use in a Sample of Southern California Community College Students

Californian Journal of Health Promotion, 2015

Background and Purpose: Hookah smoking is a growing young adult phenomenon, particularly among co... more Background and Purpose: Hookah smoking is a growing young adult phenomenon, particularly among college students. Many users feel that it is safer than other tobacco products, although its health threats are well documented. Little is known about hookah use rates in community colleges that are attended by nearly half of all US college students. This study examined hookah use in a diverse convenience sample of students attending two southern California community colleges. Methods: In fall 2011, a crosssectional, in-classroom survey was administered to 1,207 students. A series of fully adjusted multivariate logistic regressions were conducted to explore demographic, other substance use, and attitudinal correlates of lifetime and current hookah use. Results: Lifetime hookah use (56%) was higher than lifetime cigarette use (49%). Gender and personal socioeconomic status were not related to hookah use. Current use (10.8%) was associated with current use of alcohol, cigars, and cigarettes....

Research paper thumbnail of Hookah waterpipe: More prevalent than the cigarette among community college students

Results from the first ever community college study on waterpipe use (n=1,207) in fall 2011 at tw... more Results from the first ever community college study on waterpipe use (n=1,207) in fall 2011 at two demographically diverse schools in Southern California found use in the higher range of the collegiate literature (seventeen peer-reviewed studies; all from four-year schools, 2004-2011) - 55.5% reported ever using the waterpipe, and more than one in three (34.1%) used it in the previous year. More students have experimented with the waterpipe than ever smoked a cigarette, 48.8%. Current use, 10.8%, is associated with current alcohol (AOR=2.8, p<.001), current cigar (AOR=2.5, p<.01) and current cigarette use (AOR=1.8, p<.05) as well as female binge drinking (AOR=1.8, p=<.05). Compared to African-Americans, Whites are 2.9 times (p<.05) more likely to be current users. Current marijuana, illegal drug, and smokeless tobacco use are not associated with any measure of waterpipe use and there are also no gender or economic (financial aid, first generation, and hours worked per...

Research paper thumbnail of Environmental exposures, lung function, and respiratory health in rural Lao PDR

The Southeast Asian journal of tropical medicine and public health, 2014

Although the individual contributions of smoked tobacco and indoor air pollution have been identi... more Although the individual contributions of smoked tobacco and indoor air pollution have been identified, there are very few studies that have characterized and measured the effects of inhaled particles from a wide range of personal, household, and community practices common in rural Asia. The objective of our study was to examine the association between environmental inhaled exposures and lung function among rural males of Lao PDR. In a sample of 92 males from rural Lao PDR, study subjects completed a survey on household exposures, a physical exam, and the following measures of lung function: FEV1, FVC, and the ratio of FEV1/FVC. Our findings were as follows: a) > 80% of the subjects were exposed to indoor cooking fires (wood fuel), animal handling, dust and dirt; b) 57.6% of subjects were in the impaired range (FEV1/FVC < 0.7); and c) animal handling was negatively associated (p < 0.03) with FEV1 and FVC. Among males in rural Lao PDR, we found a high prevalence of chronic ex...

Research paper thumbnail of Patterns of Maternal Tobacco Use Among Cambodian Women

Asia Pacific Journal of Public Health, 2013

Although current trends indicate that the rate of cigarette smoking tends to be low among women i... more Although current trends indicate that the rate of cigarette smoking tends to be low among women in the Western Pacific Region (<10%), recent epidemiologic data from South Asia (India, Bangladesh) and Southeast Asia (Cambodia, Vietnam, Indonesia, Malaysia) identify that a large proportion of women of reproductive age and older chew tobacco—often as part of a betel quid mixture that includes other potentially harmful ingredients (eg, areca nut). Our findings from currently pregnant women identified during a nationwide survey of adult tobacco use in Cambodia indicate that 13.0% (95% confidence interval [CI] = 8% to 17%) were current users of smoked or smokeless (in the form of a betel quid) tobacco. Most pregnant women who used tobacco indicated that their habit was either initiated (29.1%; 95% CI = 16.3-46.3) or increased (33.7%; 95% CI = 18.3-53.5) during pregnancy. Pregnancy-related symptoms such as morning sickness were reported as the reason for more than half (54.9%; 95% CI = ...

Research paper thumbnail of Reliability of Meat, Fish, Dairy, and Egg Intake Over a 33-Year Interval in Adventist Health Study 2

Nutrition and Cancer, 2014

We studied Adventist Health Study 2 (AHS-2) cohort members to determine the reliability of long-t... more We studied Adventist Health Study 2 (AHS-2) cohort members to determine the reliability of long-term recall of adult dietary intake that occurred 33 years ago. Establishing the reliability of these measures supports studies of how dietary exposure across the life course affects risk of cancer and other noncommunicable disease outcomes. Among 1816 AHS-2 cohort members, we conducted a statistical comparison of long-term recall of meat, fish, dairy, and eggs at AHS-2 baseline with their report of current diet 33 years before AHS-2 baseline at an age of 30-60 years. Major findings are as follows: 1) a high correlation for frequency of red meat (R = 0.71), poultry (R = 0.67), and fish (R = 0.60); lower correlations for dairy (R = 0.19) and eggs (R = 0.28); 2) good concordance for dichotomous measures of red meat [

Research paper thumbnail of Cigarette smoking and tuberculosis in Cambodia: findings from a national sample

Tobacco Induced Diseases, 2013

Background: Cambodia has very high rates of tuberculosis and smoked tobacco use among adults. Eff... more Background: Cambodia has very high rates of tuberculosis and smoked tobacco use among adults. Efforts to control both tobacco use and tuberculosis in Cambodia need to be informed by nationally representative data. Our objective is to examine the relation between daily cigarette smoking and lifetime tuberculosis (TB) history in a national sample of adults in Cambodia. Methods: In 2011, a multi-stage, cluster sample of 15,615 adults (ages 15 years and older) from all regions of Cambodia were administered the Global Adult Tobacco Survey by interviewers from the National Institute of Statistics of Cambodia. Results: Our findings include: 1) among daily smokers, a significant positive relation between TB and number of cigarettes smoked per day (OR = 1.70 [95% CI 1.01, 2.87]) and pack-years of smoking (OR = 1.53 [95% CI 1.05, 2.25]) 2) a non-significant 58% increase in odds of ever having being diagnosed with TB among men who smoked manufactured cigarettes (OR = 1.58 [95% CI 0.97, 2.58]). Conclusion: In Cambodia, manufactured cigarette smoking was associated with lifetime TB infection and the association was most evident among the heaviest smokers (> 1 pack per day, > 30 pack years).

Research paper thumbnail of Relative Validity of a Food Frequency Questionnaire Used to Assess Food Intake During a Dietary Intervention Study

Nutrition and Cancer, 2008

To develop a cost-effective alternative for evaluating dietary intake in large-scale intervention... more To develop a cost-effective alternative for evaluating dietary intake in large-scale intervention trials of cancer and cardiovascular disease outcomes, we designed and validated a semiquantitative food frequency questionnaire (FFQ). We collected 6 to 8 of the 24-hr dietary recalls from 87 adults (ages 30-72 yr) who were randomly assigned to a walnut-supplemented diet or a control diet in a 6-mo dietary intervention trial. Relative validity of a 171-item FFQ in assessing intake of selected foods and the prescribed intervention (intake ≥25 g/day or intake <2 g of walnuts) was determined using 24-h dietary recalls as the reference. De-attenuated correlations between FFQ and dietary recalls were .82 for walnuts, .80 for fruits, .79 for grains, .77 for vegetables, .63 for water, .44 for sweets, and .36 for dairy/eggs. High within-person variation did not allow de-attenuation for the remaining foods, but uncorrected correlations were high (>.7) for the beverage variables. The FFQ correctly classified 86 out of 87 subjects in the 2 prescribed intervention groups. The FFQ can provide an accurate measure of a food-based intervention (i.e., walnut supplementation) in a trial setting and can also accurately estimate a number of other food groups consumed during the trial.

Research paper thumbnail of Waterpipe smoking and nicotine exposure: A review of the current evidence

Nicotine & Tobacco Research, 2007

The waterpipe, also known as shisha, hookah, narghile, goza, and hubble bubble, has long been use... more The waterpipe, also known as shisha, hookah, narghile, goza, and hubble bubble, has long been used for tobacco consumption in the Middle East, India, and parts of Asia, and more recently has been introduced into the smokeless tobacco market in western nations. We reviewed the published literature on waterpipe use to estimate daily nicotine exposure among adult waterpipe smokers. We identified six recent studies that measured the nicotine or cotinine levels associated with waterpipe smoking in four countries (Lebanon, Jordan, Kuwait, and India). Four of these studies directly measured nicotine or cotinine levels in human subjects. The remaining two studies used smoking machines to measure the nicotine yield in smoking condensate produced by the waterpipe. Meta-analysis of the human data indicated that daily use of the waterpipe produced a 24-hr urinary cotinine level of 0.785 µg/ml (95% CI = 0.578-0.991 µg/ml), a nicotine absorption rate equivalent to smoking 10 cigarettes/day (95% CI = 7-13 cigarettes/day). Even among subjects who were not daily waterpipe smokers, a single session of waterpipe use produced a urinary cotinine level that was equivalent to smoking two cigarettes in one day. Estimates of the nicotine produced by waterpipe use can vary because of burn temperature, type of tobacco, waterpipe design, individual smoking pattern, and duration of the waterpipe smoking habit. Our quantitative synthesis of the limited human data from four nations indicates that daily use of waterpipes produces nicotine absorption of a magnitude similar to that produced by daily cigarette use.

Research paper thumbnail of The effect of menopause on the relation between weight gain and mortality among women

Menopause, 2001

Objective: To examine the effect of menopause on the relation between weight gain and all-cause m... more Objective: To examine the effect of menopause on the relation between weight gain and all-cause mortality. Design: Prospective cohort study of 6,030 adults (ages 25-82 years) who never smoked cigarettes, had no history of coronary heart disease, cancer, or stroke, and were enrolled in a 29-year follow-up in which anthropometric data were given at baseline and at 17 years after baseline. Results: Weight gain that occurred over a 17-year interval (baseline to 17 years after baseline) increased the mortality risk of men and middle-aged women, but decreased the mortality risk of older women. Further study of the women revealed that a strong protective effect of weight gains was only evident among the leanest (Յ25 kg/m 2) postmenopausal women. Specifically, weight gains of 10 kg or more (median = 13 kg) produced an almost threefold decrease in mortality risk among the leanest (Յ25 kg/m 2) postmenopausal women [hazard ratio (HR) (95% confidence interval; CI) = 0.35 (0.13, 0.96)], but did not confer strong protection for heavier (>25 kg/m 2) postmenopausal women [HR (95% CI) = 0.81 (0.41, 1.58)] or for premenopausal women [HR (95% CI) = 1.05 (0.49, 2.25) for Յ25 kg/m 2 , 0.95 (0.38, 2.37) for >25 kg/m 2 ]. We found that the protective effect of weight gain among the leanest postmenopausal women was primarily due to a more than threefold decrease in cardiovascular disease mortality risk. One possible explanation for these findings is that weight gain increases the level of adipose-tissue-derived estrogen among lean postmenopausal women. Conclusion: Moderate menopausal weight gain may be well tolerated in lean women.

Research paper thumbnail of Does Excess Body Fat Maintained After the Seventh Decade Decrease Life Expectancy?

Journal of the American Geriatrics Society, 2011

To determine whether the attenuation in risk of death due to excess body fat seen in most studies... more To determine whether the attenuation in risk of death due to excess body fat seen in most studies of older adults may be due to confounding, the relationship between adiposity and mortality was examined in adults who never smoked, were free of major chronic diseases, and maintained stable weight over long periods. Prospective cohort study. The Adventist Health Study and Adventist Mortality Study in California. Six thousand thirty adults aged 25 to 82 who had never smoked and had no history of coronary heart disease, cancer, or stroke. During 29 years of follow-up, anthropometric data were collected at baseline and 17 years later, and mortality surveillance continued for 12 years thereafter. Data were analyzed using survival analysis with attained age as the time variable. Instantaneous hazard plots indicated that men with a body mass index (BMI) greater than 22.3 kg/m2 and women with a BMI greater than 27.4 kg/m2 had a greater mortality risk through the ninth decade than those with lower BMI. For men aged 75 to 99 who maintained stable body weight, a BMI greater than 22.3 kg/m2 was associated with a 3.7-year (95% confidence interval (CI)=1.1-6.3) shorter life expectancy and significantly greater mortality (hazard ratio (HR)=1.88, 95% CI=1.16-3.04, for BMI=22.3-27.3 kg/m2; HR=2.00, 95% CI=1.01-3.97 for BMI&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;27.3 kg/m2; reference, BMI≤22.3 kg/m2). For women aged 75 to 99 who maintained stable body weight, a BMI greater than 27.4 kg/m2 was associated with a 2.1-year (95% CI=0.5-3.8) shorter life expectancy and significantly greater mortality (HR=1.12, 95% CI=0.80-1.58 for BMI&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;20.6 kg/m2; HR=1.41, 95% CI=1.05-1.89 for BMI&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;27.4 kg/m2; reference, BMI 20.6-27.4 kg/m2). Excess body fat maintained after the seventh decade decreases life expectancy but appears to be less lethal in women.

Research paper thumbnail of Betel quid use in relation to infectious disease outcomes in Cambodia

International Journal of Infectious Diseases, 2012

Betel quid use involves the chewing of areca nut (Areca catechu L. (Arecaceae)), betel leaf (Pipe... more Betel quid use involves the chewing of areca nut (Areca catechu L. (Arecaceae)), betel leaf (Piper betle L. (Piperaceae)), slaked lime (calcium hydroxide), and tobacco, and is practiced by 600 million persons in Asia, South Asia, and Southeast Asia, 1-3 and also among migrants from those regions living in Western nations. 4 Largescale prospective cohort studies in India and Taiwan have shown that betel quid use in women and men is associated with a 20-30% increase in the all-cause mortality rate. 5,6 Some of the chronic diseases underlying this trend include (1) a well-known association with oral cancer, oral leukoplakia, and submucous fibrosis, which have primarily been attributed to the formation of carcinogenic N-nitroso compounds produced by the quid, 7 and (2) a growing body of evidence of a link with cardiovascular disease and diabetes. 8-10 Although a relationship between betel quid and periodontal infections has been reported, 11 there is a paucity of data investigating a link between betel quid and infectious, communicable disease. Qualitative and quantitative data are emerging from several nations indicating that the use of betel quid may be an integral part of cultural, familial, and traditional medicine practices. 3,4,12,13 Specifically, the betel quid ingredients are known throughout Asia and South Asia for their medicinal effects as a stimulant, a digestive aid (specifically for the relief of morning sickness during pregnancy), 12 an antiseptic, a de-worming agent, a pain reliever, and for the treatment of infectious disease. 13 During a large-scale prevalence study of tobacco use in Cambodia (N = 13 988) 12,14 in 2005-2006, we found that (1) about half the older women (>48 years) are habitual betel quid users, (2) one out of five women started the habit during pregnancy in response to morning sickness, 15 and (3) by occupation the highest prevalence of chewing tobacco was among midwives (67.9%) and traditional healers (47.1%). These data raise the possibility that traditional medicine practices are influencing the initiation and use of the betel quid in Cambodia. In the current analyses of this national sample of 13 988 adults in Cambodia, 12 our aims were (1) to examine the association between habitual betel quid use and specific infectious diseases (HIV/AIDS, tuberculosis, dengue fever, typhoid), and (2) to examine the association between betel quid use and the use of traditional medicine services (i.e., traditional healer, traditional birth attendant,

Research paper thumbnail of Mixed Methods Pilot Study of Sharing Behaviors among Waterpipe Smokers of Rural Lao PDR: Implications for Infectious Disease Transmission

International Journal of Environmental Research and Public Health, 2013

To date, the sharing behaviors associated with the homemade tobacco waterpipe used in rural areas... more To date, the sharing behaviors associated with the homemade tobacco waterpipe used in rural areas of the Western Pacific Region have not been studied. Evidence from studies of manufactured waterpipes raises the possibility of infectious disease transmission due to waterpipe sharing. The objective of our pilot study in rural Lao People's Democratic Republic (PDR) was to identify and measure the prevalence of waterpipe sharing behaviors. We first conducted ethnographic studies to investigate waterpipe-smoking behaviors. These findings were then used to develop an interviewer-administered household survey that was used in a sampling of waterpipe smokers from three villages of the Luang Namtha OPEN ACCESS province of Lao PDR (n = 43). Sampled waterpipe smokers were predominantly male (90.7%), older (mean age 49, SD 13.79), married (95.4%), farmers (78.6%), and had completed no primary education. Pipes were primarily made from bamboo (92.9%). Almost all (97.6%) smokers were willing to share their pipe with others. At the last time they smoked, smokers shared a pipe with at least one other person (1.2 ± 0.5 persons). During the past week, they had shared a pipe with five other persons (5.2 ± 3.8 persons). The high prevalence of sharing behaviors among waterpipe smokers in rural Southeast Asia raises the possibility that this behavior provides important and unmeasured social network pathways for the transmission of infectious agents.

Research paper thumbnail of Dietary Risk Factors for Ovarian Cancer: The Adventist Health Study (United States)

Cancer Causes & Control, 2006

Few prospective studies have reported dietary risk factors for ovarian cancer. A total of 71 hist... more Few prospective studies have reported dietary risk factors for ovarian cancer. A total of 71 histologically confirmed epithelial ovarian cancers occurred among 13,281 non-Hispanic white California Seventh-day Adventist women during follow-up. Participants were part of the Adventist Health Study (AHS) and had no history of cancer or hysterectomy at baseline in 1976 when they completed a detailed lifestyle questionnaire including a dietary assessment. The association of dietary variables with either all ovarian cancer cases or postmenopausal cases was tested using proportional hazards regression with adjustment for age and other covariates. The strongest hazardous risk factor associations among the food variables were found for meat intake with a risk ratio (RR) of 2.42 for intake &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; or = 1 time/week versus no meat (p for trend = 0.006), and cheese intake with a RR of 2.02 for intake of &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; 2 time/week versus &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 1 per week (p for trend = 0.10), both of these being in postmenopausal cases. We found significantly reduced risk of all ovarian cancer with higher tomato consumption (RR = 0.32) comparing intakes &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; or = five times/week versus never to &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 1 time/week (p for trend = 0.002), and also with higher fruit consumption (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01). A weak protective association was found with low fat, but not whole milk. Little confounding was observed between these foods.