John Mafi | UCLA David Geffen School of Medicine (original) (raw)
Papers by John Mafi
Journal of General Internal Medicine, 2015
ABSTRACT The Authors’ Reply—We thank Dr. Solomon for his interest in our study assessing national... more ABSTRACT The Authors’ Reply—We thank Dr. Solomon for his interest in our study assessing national trends in headache management and for raising important questions about the usefulness of lifestyle modification counseling. As noted, we found a decline in first-line recommended lifestyle modification counseling for headache over the past decade, contrary to prominent headache guidelines.1 For instance, guidelines from the American College of Physicians suggest that physicians encourage their patients to identify and avoid specific dietary, behavioral, and environmental triggers for migraine headache.2While he is correct in pointing out that generic advice on improving diet and exercise habits may lack rigorous scientific evidence showing reduced headache frequency, the dietary and lifestyle counseling provided during a headache visit would likely be targeted towards specific factors that trigger headache. Moreover, we do not agree that “increased stress, dehydration, lack of sleep, sedentary lif ...
JAMA Internal Medicine, 2014
JAMA Internal Medicine, 2013
Back pain treatment is costly and frequently includes overuse of treatments that are unsupported ... more Back pain treatment is costly and frequently includes overuse of treatments that are unsupported by clinical guidelines. Few studies have evaluated recent national trends in guideline adherence of spine-related care. To characterize the treatment of back pain from January 1, 1999, through December 26, 2010. Using nationally representative data from the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey, we studied outpatient visits with a chief symptom and/or primary diagnosis of back or neck pain, as well as those with secondary symptoms and diagnoses of back or neck pain. We excluded visits with concomitant "red flags," including fever, neurologic symptoms, or cancer. Results were analyzed using logistic regression adjusted for patient and health care professional characteristics and weighted to reflect national estimates. We also present adjusted results stratified by symptom duration and whether the health care professional was the primary care physician (PCP). We assessed imaging, narcotics, and referrals to physicians (guideline discordant indicators). In addition, we evaluated use of nonsteroidal anti-inflammatory drugs or acetaminophen and referrals to physical therapy (guideline concordant indicators). We identified 23,918 visits for spine problems, representing an estimated 440 million visits. Approximately 58% of patients were female. Mean age increased from 49 to 53 years (P< .001) during the study period. Nonsteroidal anti-inflammatory drug or acetaminophen use per visit decreased from 36.9% in 1999-2000 to 24.5% in 2009-2010 (unadjusted P< .001). In contrast, narcotic use increased from 19.3% to 29.1% (P< .001). Although physical therapy referrals remained unchanged at approximately 20%, physician referrals increased from 6.8% to 14.0% (P< .001). The number of radiographs remained stable at approximately 17%, whereas the number of computed tomograms or magnetic resonance images increased from 7.2% to 11.3% during the study period (P< .001). These trends were similar after stratifying by short-term vs long-term presentations, visits to PCPs vs non-PCPs, and adjustment for age, sex, race/ethnicity, PCP status, symptom duration, region, and metropolitan location. Despite numerous published clinical guidelines, management of back pain has relied increasingly on guideline discordant care. Improvements in the management of spine-related disease represent an area of potential cost savings for the health care system with the potential for improving the quality of care.
Emergency radiology, 2011
We compared the effect of low-density barium sulfate neutral oral contrast agent on the diameter ... more We compared the effect of low-density barium sulfate neutral oral contrast agent on the diameter of normal appendix and its luminal content versus that of water on multidetector-row CT. CT scans of 24 patients who had been imaged on two separate occasions for the evaluation of pancreatic pathology, once with water and subsequently with low-density barium sulfate as the neutral oral contrast agent were evaluated (total of 48 scans). Studies were randomized and reviewed in consensus on a workstation in the stack mode by two radiologists blinded to the type of oral contrast. The appendix was measured at baseline and 10 days later to obtain an average diameter. Results of the water and low-density barium sulfate groups were compared using paired t test. Contents of the appendiceal lumen were also noted (gas, fluid, mixed, and collapsed appendix). The average diameter of the appendix for scans obtained with water and low-density barium sulfate was 4.09 ± 0.87 mm (median, 4.22 mm; range, ...
Journal of general internal medicine, Jan 8, 2015
Headache is a frequent complaint and among the most common reasons for visiting a physician. To c... more Headache is a frequent complaint and among the most common reasons for visiting a physician. To characterize trends from 1999 through 2010 in the management of headache. Longitudinal trends analysis. Nationally representative sample of visits to clinicians for headache from the National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey, excluding visits with "red flags," such as neurologic deficit, cancer, or trauma. Use of advanced imaging (CT/MRI), opioids/barbiturates, and referrals to other physicians (guideline-discordant indicators), as well as counseling on lifestyle modifications and use of preventive medications including verapamil, topiramate, amitriptyline, or propranolol (guideline-concordant during study period). We analyzed results using logistic regression, adjusting for patient and clinician characteristics, and weighted to reflect U.S. population estimates. Additionally, we stratified findings based on migraine versus non-...
Journal of Digital Imaging, 2012
Cardiovascular disease is the leading cause of global mortality, yet its early detection remains ... more Cardiovascular disease is the leading cause of global mortality, yet its early detection remains a vexing problem of modern medicine. Although the computed tomography (CT) calcium score predicts cardiovascular risk, relatively high cost ($250-400) and radiation dose (1-3 mSv) limit its universal utility as a screening tool. Dualenergy digital subtraction radiography (DE; <$60, 0.07 mSv) enables detection of calcified structures with high sensitivity. In this pilot study, we examined DE radiography's ability to quantify coronary artery calcification (CAC). We identified 25 patients who underwent noncontrast CT and DE chest imaging performed within 12 months using documented CAC as the major inclusion criteria. A DE calcium score was developed based on pixel intensity multiplied by the area of the calcified plaque. DE scores were plotted against CT scores. Subsequently, a validation cohort of 14 additional patients was independently evaluated to confirm the accuracy and precision of CAC quantification, yielding a total of 39 subjects. Among all subjects (n=39), the DE score demonstrated a correla-tion coefficient of 0.87 (p<0.0001) when compared with the CT score. For the 13 patients with CT scores of <400, the correlation coefficient was −0.26. For the 26 patients with CT scores of ≥400, the correlation coefficient yielded 0.86. This pilot study demonstrates the feasibility of DE radiography to identify patients at the highest cardiovascular risk. DE radiography's accuracy at lower scores remains unclear. Further evaluation of DE radiography as an inexpensive and low-radiation imaging tool to diagnose cardiovascular disease appears warranted.
The American Journal of Emergency Medicine, 2011
Troponin concentrations rising above an institutional cutpoint are used to define acute myocardia... more Troponin concentrations rising above an institutional cutpoint are used to define acute myocardial necrosis, yet it is uncertain what outcomes are associated with fluctuations in troponin that do not exceed this level. We evaluate the association between troponin fluctuations below an institutional upper limit of normal and acute coronary syndrome (ACS). This was a post hoc analysis of the Internet tracking registry of ACS (i*trACS), which describes patients presenting to emergency departments (EDs) with suspected ACS across the spectrum of risk. Patients were included in this registry if they were at least 18 years old and had suspected ACS at the time of their ED visit. Inclusions in this analysis required that patients had at least 1 cardiac marker (creatine kinase-MB [CK-MB], troponin T, or troponin I) drawn twice within 6 hours of presentation, with both measures being below the institution&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;#39;s upper limit of normal. A marker change was defined as either an increase or decrease that exceeded 15% of the institutional upper limit of normal. Acute coronary syndrome was defined as a positive stress test, documented myocardial infarction, coronary revascularization, or death within 30 days of their ED admission. Of 17,713 patient visits, 2162 met inclusion and exclusion criteria. There were 1872 patient visits with 2 troponin results and 1312 with 2 CK-MB results. Patient visits with increasing troponin had increased odds of ACS compared with those with stable troponin levels (odds ratio, 3.6; 95% confidence interval, 1.4-9.2). Changing CK-MB and decreasing troponin were not associated with increased odds of ACS. Small increases in troponin concentration below the upper limit of normal are associated with increased odds of ACS.
Journal of General Internal Medicine, 2015
ABSTRACT The Authors’ Reply—We thank Dr. Solomon for his interest in our study assessing national... more ABSTRACT The Authors’ Reply—We thank Dr. Solomon for his interest in our study assessing national trends in headache management and for raising important questions about the usefulness of lifestyle modification counseling. As noted, we found a decline in first-line recommended lifestyle modification counseling for headache over the past decade, contrary to prominent headache guidelines.1 For instance, guidelines from the American College of Physicians suggest that physicians encourage their patients to identify and avoid specific dietary, behavioral, and environmental triggers for migraine headache.2While he is correct in pointing out that generic advice on improving diet and exercise habits may lack rigorous scientific evidence showing reduced headache frequency, the dietary and lifestyle counseling provided during a headache visit would likely be targeted towards specific factors that trigger headache. Moreover, we do not agree that “increased stress, dehydration, lack of sleep, sedentary lif ...
JAMA Internal Medicine, 2014
JAMA Internal Medicine, 2013
Back pain treatment is costly and frequently includes overuse of treatments that are unsupported ... more Back pain treatment is costly and frequently includes overuse of treatments that are unsupported by clinical guidelines. Few studies have evaluated recent national trends in guideline adherence of spine-related care. To characterize the treatment of back pain from January 1, 1999, through December 26, 2010. Using nationally representative data from the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey, we studied outpatient visits with a chief symptom and/or primary diagnosis of back or neck pain, as well as those with secondary symptoms and diagnoses of back or neck pain. We excluded visits with concomitant &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;red flags,&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; including fever, neurologic symptoms, or cancer. Results were analyzed using logistic regression adjusted for patient and health care professional characteristics and weighted to reflect national estimates. We also present adjusted results stratified by symptom duration and whether the health care professional was the primary care physician (PCP). We assessed imaging, narcotics, and referrals to physicians (guideline discordant indicators). In addition, we evaluated use of nonsteroidal anti-inflammatory drugs or acetaminophen and referrals to physical therapy (guideline concordant indicators). We identified 23,918 visits for spine problems, representing an estimated 440 million visits. Approximately 58% of patients were female. Mean age increased from 49 to 53 years (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001) during the study period. Nonsteroidal anti-inflammatory drug or acetaminophen use per visit decreased from 36.9% in 1999-2000 to 24.5% in 2009-2010 (unadjusted P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001). In contrast, narcotic use increased from 19.3% to 29.1% (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001). Although physical therapy referrals remained unchanged at approximately 20%, physician referrals increased from 6.8% to 14.0% (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001). The number of radiographs remained stable at approximately 17%, whereas the number of computed tomograms or magnetic resonance images increased from 7.2% to 11.3% during the study period (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001). These trends were similar after stratifying by short-term vs long-term presentations, visits to PCPs vs non-PCPs, and adjustment for age, sex, race/ethnicity, PCP status, symptom duration, region, and metropolitan location. Despite numerous published clinical guidelines, management of back pain has relied increasingly on guideline discordant care. Improvements in the management of spine-related disease represent an area of potential cost savings for the health care system with the potential for improving the quality of care.
Emergency radiology, 2011
We compared the effect of low-density barium sulfate neutral oral contrast agent on the diameter ... more We compared the effect of low-density barium sulfate neutral oral contrast agent on the diameter of normal appendix and its luminal content versus that of water on multidetector-row CT. CT scans of 24 patients who had been imaged on two separate occasions for the evaluation of pancreatic pathology, once with water and subsequently with low-density barium sulfate as the neutral oral contrast agent were evaluated (total of 48 scans). Studies were randomized and reviewed in consensus on a workstation in the stack mode by two radiologists blinded to the type of oral contrast. The appendix was measured at baseline and 10 days later to obtain an average diameter. Results of the water and low-density barium sulfate groups were compared using paired t test. Contents of the appendiceal lumen were also noted (gas, fluid, mixed, and collapsed appendix). The average diameter of the appendix for scans obtained with water and low-density barium sulfate was 4.09 ± 0.87 mm (median, 4.22 mm; range, ...
Journal of general internal medicine, Jan 8, 2015
Headache is a frequent complaint and among the most common reasons for visiting a physician. To c... more Headache is a frequent complaint and among the most common reasons for visiting a physician. To characterize trends from 1999 through 2010 in the management of headache. Longitudinal trends analysis. Nationally representative sample of visits to clinicians for headache from the National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey, excluding visits with "red flags," such as neurologic deficit, cancer, or trauma. Use of advanced imaging (CT/MRI), opioids/barbiturates, and referrals to other physicians (guideline-discordant indicators), as well as counseling on lifestyle modifications and use of preventive medications including verapamil, topiramate, amitriptyline, or propranolol (guideline-concordant during study period). We analyzed results using logistic regression, adjusting for patient and clinician characteristics, and weighted to reflect U.S. population estimates. Additionally, we stratified findings based on migraine versus non-...
Journal of Digital Imaging, 2012
Cardiovascular disease is the leading cause of global mortality, yet its early detection remains ... more Cardiovascular disease is the leading cause of global mortality, yet its early detection remains a vexing problem of modern medicine. Although the computed tomography (CT) calcium score predicts cardiovascular risk, relatively high cost ($250-400) and radiation dose (1-3 mSv) limit its universal utility as a screening tool. Dualenergy digital subtraction radiography (DE; <$60, 0.07 mSv) enables detection of calcified structures with high sensitivity. In this pilot study, we examined DE radiography's ability to quantify coronary artery calcification (CAC). We identified 25 patients who underwent noncontrast CT and DE chest imaging performed within 12 months using documented CAC as the major inclusion criteria. A DE calcium score was developed based on pixel intensity multiplied by the area of the calcified plaque. DE scores were plotted against CT scores. Subsequently, a validation cohort of 14 additional patients was independently evaluated to confirm the accuracy and precision of CAC quantification, yielding a total of 39 subjects. Among all subjects (n=39), the DE score demonstrated a correla-tion coefficient of 0.87 (p<0.0001) when compared with the CT score. For the 13 patients with CT scores of <400, the correlation coefficient was −0.26. For the 26 patients with CT scores of ≥400, the correlation coefficient yielded 0.86. This pilot study demonstrates the feasibility of DE radiography to identify patients at the highest cardiovascular risk. DE radiography's accuracy at lower scores remains unclear. Further evaluation of DE radiography as an inexpensive and low-radiation imaging tool to diagnose cardiovascular disease appears warranted.
The American Journal of Emergency Medicine, 2011
Troponin concentrations rising above an institutional cutpoint are used to define acute myocardia... more Troponin concentrations rising above an institutional cutpoint are used to define acute myocardial necrosis, yet it is uncertain what outcomes are associated with fluctuations in troponin that do not exceed this level. We evaluate the association between troponin fluctuations below an institutional upper limit of normal and acute coronary syndrome (ACS). This was a post hoc analysis of the Internet tracking registry of ACS (i*trACS), which describes patients presenting to emergency departments (EDs) with suspected ACS across the spectrum of risk. Patients were included in this registry if they were at least 18 years old and had suspected ACS at the time of their ED visit. Inclusions in this analysis required that patients had at least 1 cardiac marker (creatine kinase-MB [CK-MB], troponin T, or troponin I) drawn twice within 6 hours of presentation, with both measures being below the institution&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;#39;s upper limit of normal. A marker change was defined as either an increase or decrease that exceeded 15% of the institutional upper limit of normal. Acute coronary syndrome was defined as a positive stress test, documented myocardial infarction, coronary revascularization, or death within 30 days of their ED admission. Of 17,713 patient visits, 2162 met inclusion and exclusion criteria. There were 1872 patient visits with 2 troponin results and 1312 with 2 CK-MB results. Patient visits with increasing troponin had increased odds of ACS compared with those with stable troponin levels (odds ratio, 3.6; 95% confidence interval, 1.4-9.2). Changing CK-MB and decreasing troponin were not associated with increased odds of ACS. Small increases in troponin concentration below the upper limit of normal are associated with increased odds of ACS.