Osama Moharram - Academia.edu (original) (raw)

Papers by Osama Moharram

BMC Pediatrics, 2012

Background Accumulating evidence suggests an increased prevalence of vitamin D deficiency in the ... more Background Accumulating evidence suggests an increased prevalence of vitamin D deficiency in the Middle East. In this context, we aimed to determine whether the prevalence of vitamin D deficiency is related to degree of physical activity and sun exposure among apparently healthy Saudi children and adolescents, a little studied population. Methods A total of 331 Saudi children aged 6–17 years (153 boys and 178 girls) were included in this cross sectional study. Levels of physical activity and sun exposure were determined using a standard questionnaire. Anthropometry, serum calcium and 25-(OH) vitamin D were analyzed. Results All subjects were vitamin D deficient, the majority being moderately deficient (71.6%). Age was the single most significant predictor affecting 25 (OH) Vitamin D levels, explaining 21% of the variance perceived (p = 1.68 x 10-14). Age-matched comparisons revealed that for groups having the same amount of sun exposure, those with moderate or are physically active ...

International …, 1998

Purpose: To describe the incidence of, and risk factors associated with, diabetic retinopathy in ... more Purpose: To describe the incidence of, and risk factors associated with, diabetic retinopathy in diabetic persons assessed at a Saudi diabetes centre. Methods: Five hundred and two patients with diabetes mellitus assessed by our service were studied. There were 174 patients (34.7%) with insulin-dependent diabetes mellitus (IDDM) and 328 patients (65.3%) with non-insulin-dependent diabetes mellitus (NIDDM). Results: The incidence of retinopathy was 157/502 (31.3%). The incidence was 42.5% in patients with IDDM and 25.3% in those with NIDDM. By logistic regression analysis, it was shown that old age (>60 years), insulin use, long duration of diabetes (>10 years), poor diabetes control, and the presence of nephropathy were significantly associated with the incidence of retinopathy. On the basis of the magnitudes of the regression coefficients in the hazard function, long duration of diabetes was the most important independent risk factor for the development of retinopathy; the presence of nephropathy, age >60 years, poor diabetes control, and use of insulin were less important (regression coefficients: 1.9, 1.71, 1.331, 0.8508 and 0.6178, respectively). The incidence of macular oedema was significantly associated with the presence of hypertension and high cholesterol levels in patients with IDDM. Polycotomous regression analysis showed that the presence of nephropathy was the only factor significantly associated with the severity of retinopathy. Conclusions: The significant associations with poor control and duration of diabetes provide further strong evidence for the benefits of optimal glycaemic control. Other potentially modifiable risk factors for retinopathy may be important, including elevated blood pressure and serum cholesterol.

International ophthalmology, 2001

Early predictors of diabetic complications may aid in the prevention and/or management of these c... more Early predictors of diabetic complications may aid in the prevention and/or management of these complications. The aim of this cross-sectional study was to determine the predictive value of retinopathy for the presence of other diabetic complications. The population studied comprised 648 patients with diabetes mellitus assessed by our service. There were 210 patients (32.4%) with insulin-dependent diabetes mellitus (IDDM), and 438 patients (67.6%) with non-insulin-dependent diabetes mellitus (NIDDM). Univariate analyses revealed that retinopathy significantly predicted the presence of neuropathy (odds ratio [OR] = 2.23; 95% confidence interval [CI] = 1.56-3.18; p < 0.001), nephropathy (OR = 5.68; 95% CI = 3.06-10.62; p < 0.001), and cerebrovascular disease (OR = 6.6; 95% CI = 1.16-67.21; p = 0.0239) in the total group. Similar associations were observed both in subjects with IDDM and NIDDM. The associations between retinopathy severity level and the prevalence rate of nephropa...

Endocrine Abstracts, 2013

Nutrition Journal, 2012

Coffee and tea consumption was hypothesized to interact with variants of vitamin D-receptor polym... more Coffee and tea consumption was hypothesized to interact with variants of vitamin D-receptor polymorphisms, but limited evidence exists. Here we determine for the first time whether increased coffee and tea consumption affects circulating levels of 25-hydroxyvitamin D in a cohort of Saudi adolescents. A total of 330 randomly selected Saudi adolescents were included. Anthropometrics were recorded and fasting blood samples were analyzed for routine analysis of fasting glucose, lipid levels, calcium, albumin and phosphorous. Frequency of coffee and tea intake was noted. 25-hydroxyvitamin D levels were measured using enzyme-linked immunosorbent assays. Improved lipid profiles were observed in both boys and girls, as demonstrated by increased levels of HDL-cholesterol, even after controlling for age and BMI, among those consuming 9-12 cups of coffee/week. Vitamin D levels were significantly highest among those consuming 9-12 cups of tea/week in all subjects (p-value 0.009) independent of age, gender, BMI, physical activity and sun exposure. This study suggests a link between tea consumption and vitamin D levels in a cohort of Saudi adolescents, independent of age, BMI, gender, physical activity and sun exposure. These findings should be confirmed prospectively.

Metabolism, 2012

Numerous cross-sectional studies have noted significant negative associations between circulating... more Numerous cross-sectional studies have noted significant negative associations between circulating levels of 25-hydroxyvitamin D and cardiometabolic risk factors, highlighting potential extraskeletal functions of this sterol hormone. Prospective studies, however, have been limited; and hence, no cause-and-effect relations can be inferred. This study aims to determine whether vitamin D status correction can reverse already established manifestations of the metabolic syndrome (MetS). A total of 59 adult nondiabetic, overweight, and obese Saudis (31 male, 28 female) were prospectively enrolled in this 1-year interventional study. Anthropometry and biochemical evaluation were performed, including determination of serum 25-hydroxyvitamin D, calcium, and phosphorous concentrations, as well as fasting blood glucose and lipid profile. Subjects were advised to regularly expose themselves to sunlight and increase intake of vitamin D-rich foods. All measurements were repeated 6 and 12 months later. At the initial baseline visit, the prevalence of both low high-density lipoprotein cholesterol and hypertension was significantly increased among patients with 25-vitamin D deficiency (P < .05), even after adjusting for sex and body mass index. Overall prevalence of MetS patients by the modified National Health and Nutrition Examination Survey Adult Treatment Panel III definition decreased from 25.2% to 13.0%; A v a i l a b l e o n l i n e a t w w w . s c i e n c e d i r e c t . c o m Metabolism w w w . m e t a b o l i s m j o u r n a l . c o m

Cardiovascular Diabetology, 2012

Background: Vitamin D deficiency has been associated with impaired human insulin action, suggesti... more Background: Vitamin D deficiency has been associated with impaired human insulin action, suggesting a role in the pathogenesis of diabetes mellitus type 2 (T2DM). In this prospective interventional study we investigated the effects of vitamin D3 supplementation on the metabolic profiles of Saudi T2DM subjects pre-and post-vitamin D supplementation over an 18-month period.

Cardiovascular Diabetology, 2013

Little or no research has determined the effect of vitamin D3 supplementation in conjunction with... more Little or no research has determined the effect of vitamin D3 supplementation in conjunction with pharmacological and non-pharmacological approaches in the diabetes mellitus type 2 (DMT2) patients. The objective of this study was to determine the effect of vitamin D3 supplementation in a cohort of Saudi DMT2 population on diet, insulin and/or different oral hypoglycemic agents and compare them with a non-DMT2 control cohort. A total of 499 randomly selected Saudi subjects divided into 8 groups [Non-DMT2 Control = 151; Rosiglitazone alone = 49; Diet = 15; Insulin alone = 55; Insulin + Orals = 12; Metformin alone = 121; Oral agents combination = 37; Sulphonylurea alone = 59] were included in this 12-month interventional study. All DMT2 patients were given 2000 IU vitamin D3 daily, while the control group received none but were advised to increase sun exposure. Anthropometrics, glucose, lipid profile and 25-hydroxyvitamin D (25-OHVitD) were measured at baseline, 6 and 12 months. Circulating 25-OHVitD concentrations improved in all patient groups. The metformin group showed the highest change in circulating vitamin D levels both at 6 months (62.6%) and 12 months (50.6%) as compared to baseline (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;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001). No significant changes were observed in the BMI and glucose in any of the DMT2 groups. In contrast, the insulin + oral agents group showed more significant improvements in the metabolic profile, which included triglycerides and total cholesterol, as well as systolic blood pressure and HDL-cholesterol in males. Also, significant decreases in triglycerides were observed in the rosiglitazone and insulin + oral hypoglycemic agent groups both at 6 and 12 months of supplementation (both p-values &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;amp;amp;amp;amp;amp;amp;lt;0.001). While in all DMT2 groups circulating levels of 25-OHVitD increased after supplementation, in DMT2 patients on insulin in combination with other drugs benefitted the most in improving cardiovascular risk. Metformin improves 25-hydroxyvitamin D levels but did not seem to confer other added cardiometabolic benefits.

International ophthalmology

To describe the incidence of, and risk factors associated with, diabetic retinopathy in diabetic ... more To describe the incidence of, and risk factors associated with, diabetic retinopathy in diabetic persons assessed at a Saudi diabetes centre. Five hundred and two patients with diabetes mellitus assessed by our service were studied. There were 174 patients (34.7%) with insulin-dependent diabetes mellitus (IDDM) and 328 patients (65.3%) with non-insulin-dependent diabetes mellitus (NIDDM). The incidence of retinopathy was 157/502 (31.3%). The incidence was 42.5% in patients with IDDM and 25.3% in those with NIDDM. By logistic regression analysis, it was shown that old age (>60 years), insulin use, long duration of diabetes (>10 years), poor diabetes control, and the presence of nephropathy were significantly associated with the incidence of retinopathy. On the basis of the magnitudes of the regression coefficients in the hazard function, long duration of diabetes was the most important independent risk factor for the development of retinopathy; the presence of nephropathy, age ...