Azadeh Zabetian

Rural diabetes prevalence quintuples over twenty-five years in low- and middle-income countries: a systematic review and meta-analysis.

AIMS To verify the assertions that diabetes pandemic may be spreading across rural parts of low- and middle-income countries (LMICs), we performed a systematic review of published studies reporting diabetes prevalence in rural parts of LMICs. METHODS Electronic databases (EMBASE and MEDLINE) were searched for papers published from 1990 to 2011. Two independent reviewers screened the articles using structured criteria for inclusion and performed full-text reviews. Pooled prevalence of diabetes was estimated using meta-analysis. Potential factors influencing the estimates were identified by meta-regression and used for sensitivity analyses. RESULTS Rural prevalence of diabetes of LMICs was 5.6% (95% CI=4.6-6.6), and similar between men and women. This estimate remained robust in separate sensitivity analyses accounting for study quality, level of heterogeneity, age, and sex. In a multivariate meta-regression analysis, pooled prevalence varied by study year and region. Diabetes prevalence increased over time, from 1.8% (1.0-2.6) in 1985-1989, 5.0% (3.8-6.3) in 1990-1994, 5.2% (4.1-6.2) in 1995-1999, 6.4% (5.1-7.7) in 2000-2004, and to 8.6% (6.4-10.7) for 2005-2010 (p=0.001 for secular trend). CONCLUSIONS Prevalence of diabetes in rural parts of LMICs has risen dramatically. As 55% of LMIC populations live in rural areas, this trend has enormous implications for the global burden of diabetes.

Cardiometabolic Risk Factor Changes Observed in Diabetes Prevention Programs in US Settings: A Systematic Review and Meta-analysis

Background The Diabetes Prevention Program (DPP) study showed that weight loss in high-risk adults lowered diabetes incidence and cardiovascular disease risk. No prior analyses have aggregated weight and cardiometabolic risk factor changes observed in studies implementing DPP interventions in nonresearch settings in the United States. Methods and Findings In this systematic review and meta-analysis, we pooled data from studies in the United States implementing DPP lifestyle modification programs (focused on modest [5%–7%] weight loss through ≥150 min of moderate physical activity per week and restriction of fat intake) in clinical, community, and online settings. We reported aggregated pre- and post-intervention weight and cardiometabolic risk factor changes (fasting blood glucose [FBG], glycosylated hemoglobin [HbA1c], systolic or diastolic blood pressure [SBP/DBP], total [TC] or HDL-cholesterol). We searched the MEDLINE, EMBASE, Cochrane Library, and Clinicaltrials.gov databases from January 1, 2003, to May 1, 2016. Two reviewers independently evaluated article eligibility and extracted data on study designs, populations enrolled, intervention program characteristics (duration, number of core and maintenance sessions), and outcomes. We used a random effects model to calculate summary estimates for each outcome and associated 95% confidence intervals (CI). To examine sources of heterogeneity, results were stratified according to the presence of maintenance sessions, risk level of participants (prediabetes or other), and intervention delivery personnel (lay or professional). Forty-four studies that enrolled 8,995 participants met eligibility criteria. Participants had an average age of 50.8 years and body mass index (BMI) of 34.8 kg/m2, and 25.2% were male. On average, study follow-up was 9.3 mo (median 12.0) with a range of 1.5 to 36 months; programs offered a mean of 12.6 sessions, with mean participant attendance of 11.0 core sessions. Sixty percent of programs offered some form of post-core maintenance (either email or in person). Mean absolute changes observed were: weight -3.77 kg (95% CI: -4.55; -2.99), HbA1c -0.21% (-0.29; -0.13), FBG -2.40 mg/dL (-3.59; -1.21), SBP -4.29 mmHg (-5.73, -2.84), DBP -2.56 mmHg (-3.40, 1.71), HDL +0.85 mg/dL (-0.10, 1.60), and TC -5.34 mg/dL (-9.72, -0.97). Programs with a maintenance component achieved greater reductions in weight (additional -1.66kg) and FBG (additional -3.14 mg/dl). Findings are subject to incomplete reporting and heterogeneity of studies included, and confounding because most included studies used pre-post study designs. Conclusions DPP lifestyle modification programs achieved clinically meaningful weight and cardiometabolic health improvements. Together, these data suggest that additional value is gained from these programs, reinforcing that they are likely very cost-effective.

Diabetes in the Middle East and North Africa

AIMS Even though the Middle East and North Africa (MENA) region had the highest comparative prevalence of diabetes in 2012, little is known about the nuances of diabetes risk and capacity to address the burdens. To provide a comprehensive overview, we reviewed the literature on diabetes in the MENA region. METHODS We conducted a systematic search in PubMed between January 1990 and January 2012 for studies on diabetes in the MENA region without language restriction. RESULTS There was a paucity of country-specific epidemiology data in the region. Diabetes prevalence varied widely across studies, from 2.5% in 1982 to 31.6% in 2011. Older age and higher body mass index were the most strongly associated risk factors for diabetes. Among people with diabetes, over half did not meet recommended care targets. In addition, macrovascular and microvascular complications were observed in 9-12% and 15-54% of diabetes population, respectively. CONCLUSIONS This review suggests a need for more representative surveillance data in this noteworthy focal point of the global diabetes epidemic. Such actions will not only help to understand the actual burden of diabetes but also motivate actions on design and implementation of diabetes prevention and control programs.

Weight change and incident metabolic syndrome in Iranian men and women; a 3 year follow-up study

BackgroundAlthough the association of weight gain and developing metabolic syndrome (MetS) has been reported in the Western and Asian populations, data on the gender-stratified effects of weight change (including weight loss) on incident MetS and its components in the Middle East Caucasians is still scarce.MethodsA total of 1431 men and 2036 women aged ≥ 20 years with BMI > 18.5 kg/m2 were followed over 3 years. Multivariate logistic regression analysis was used to estimate the relative risk (RR) of MetS and its components (the Adult Treatment Panel III definition) associated with gender-stratified quintiles of percent weight change. Subjects with MetS at baseline were excluded for analyzing the RR of MetS.ResultsThere was 20.4% (95% CI, 19.6–21.2) age-adjusted incident MetS (18.4% male vs. 23.1% women). In men, mild weight gain (WG) predicted high waist circumference (WC) and high triglyceride; moderate WG predicted MetS (RR 2.5, 95% CI 1.4–4.3), high WC and high blood pressure (BP); large WG predicted MetS (RR 3.2, 95% CI 1.8–5.7) and its components, except for high fasting plasma glucose. In women, mild WG predicted MetS (RR 2.5, 95% CI 1.4–4.3), high WC and high BP; moderate WG predicted Mets (RR 4.6, 95% CI 2.7–8.0), high WC and high triglyceride; large WG predicted MetS (RR 6.6, 95% CI 3.8–11.3) and its components except for low HDL-cholesterol. Mild weight loss had protective effect on high WC in both genders and MetS in men (RR 0.5, 95% CI 0.26–0.97, P = 0.04).ConclusionWeight change showed different effects on MetS in men and women. In women, mild WG predicted MetS; however, mild weight loss was protective against MetS in men and high WC in both genders.

Global rural diabetes prevalence: A systematic review and meta-analysis covering 1990–2012

AIM To investigate diabetes prevalence in rural areas globally and how it has changed over time in high-income countries (HIC) and low-middle income countries (LMIC). METHODS We systematically searched four electronic databases (MEDLINE, EMBASE, Cochrane Library, and CINAHL) for studies reporting rural prevalence of diabetes between January 1990 and January 2012. We used random effect meta-analysis to estimate pooled prevalence and metaregression to identify factors that may be associated with our estimates. FINDINGS We included 109 population-based surveys involving 1,100,746 individuals. Pooled global rural prevalence of diabetes was 6.8% (95% confidence intervals: 6.1-7.6) with no gender difference. Considering five-year increments between 1985 and 2011, when studies were conducted, global rural prevalence was 5.7% (3.5-7.9) during 1985-1989 and 8.7% (6.8-10.7) during 2005-2011. In LMICs, rural diabetes prevalence was 1.8% (1.0-2.6) during 1985-1989 and 7.5% (5.6-9.5) during 2005-2011. In HICs, rural diabetes prevalence was 8.2% (6.0-10.4) during 1985-1989 and 14.3% (8.7-20) in the most recent period. CONCLUSION Diabetes prevalence has increased in all rural areas globally but relative growth was faster in LMIC than HIC rural areas. These data suggest a need to expand diabetes surveillance to rural areas using standardized measures, as well as the need to devise and deploy appropriate prevention and control interventions.

Genetic Studies of Type 2 Diabetes in South Asians: A Systematic Overview

Diabetes Mellitus, which affects 366 million people worldwide, is a leading cause of mortality, morbidity, and loss of quality of life. South Asians, comprising 24% of the worlds population, suffer a large burden of type 2 diabetes. With intriguing risk phenotypes, unique environmental triggers, and potential genetic predisposition, South Asians offer a valuable resource for investigating the pathophysiology of type 2 diabetes. Genomics has proven its potential to underpin some of the etiology of type 2 diabetes by identifying a number of susceptibility genes, but such data are scarce and unclear in South Asians. We present a systematic review of studies on the genetic basis of type 2 diabetes or its complications in South Asians published between 1987-2012, and discuss the findings and limitations of the available data. Of the 91 eligible studies meeting our inclusion criteria, a vast majority included Indian populations, followed by a few in those of Pakistani origin, while other South Asian countries were generally under-represented. Though a large number of studies focused on the replication of findings from genome-wide association studies (GWAS) in European populations, a few studies explored new genes and pathways along with GWAS in South Asians and suggested the potential to unravel population- specific susceptibility genes in this population. We find encouraging improvements in study designs, sample sizes and the numbers of genetic variants investigated over the last five years, which reflect the existing capacity and scope for large-scale genetic studies in South Asians.