Assessing the relationship between obesity and type II diabetes among South Asian Indians in Houston A population based study

Objective: My study aimed at determining the association between obesity and diabetes prevalence in South Asian Indian immigrants in Houston, Texas. To also compare the prevalence odds of diabetes given obesity, using WHO-BMI criteria and recommended Asian ethnic-specific BMI criteria for obesity, as well as using WHO-standard waist circumference criteria and ethnic-specific criteria for abdominal obesity, across gender and age, in this population. ^ Methods: My study was a secondary data analysis based on a cross-sectional study carried out on adult South Asian Indians who attended a local community health fair in Houston, in 2007. They recruited 213 voluntary, eligible, South Asian Indian participants aged between 18 to 79 years. Self reported history of Diabetes was obtained and height, weight, waist and hip circumference were measured. I classified BMI based on WHO-standard and ethnic-specific criteria, according to gender and age groups of 18–35 years, 36–64 years and 65 years and over. Waist circumference was also classified based on WHO-standard NCEP criteria and currently recommended ethnic-specific IDF criteria and analysis was done stratifying by gender and age groups. ^ Results: The prevalence of diabetes in this population was 14.6%, significantly higher in older age groups (25.8%) and males (19.2%). The prevalence of DM was statistically similar in individuals who were overweight/obese compared to those not overweight/obese, however in overweight/obese individuals, there was a statistically significant difference in the prevalence of DM between WHO and ethnic-specific criteria for both BMI and waist circumference. In older adults and in males, ethnic-specific criteria identified significantly more as overweight/obese compared to WHO-standard criteria. ^ Conclusions: Ethnic-specific criteria for both BMI and waist circumference give a better estimate for obesity in this South Asian Indian population. Diabetes is highly prevalent in migrant South Asian Indians even at low BMI or waist circumference levels and significantly more in males and older age groups, hence adequate awareness should be created for early prevention and intervention.^

Evaluation of androgenicity, abdominal adiposity, blood pressure and types of ovulatory patterns in a sample of women with menstrual irregularities

Objective: To determine the prevalence of and the relationships between the degree and source of hyperandrogenemia, ovulatory patterns and cardiovascular disease risk indicators (blood pressure, indices or amount of obesity and fat distribution) in women with menstrual irregularities seen at endocrinologists' clinic. Design: A cross-sectional study design. Participants: A sample of 159 women with menstrual irregularities, aged 15-44, seen at endocrinologists' clinic. Main Outcome Measures: androgen levels, body mass index (BMI), waist-hip ratio (WHR), systolic and diastolic blood pressure (SBP & DBP), source of androgens, ovulatory activity. Results: The prevalence of hyperandrogenemia was 54.7% in this study sample. As expected, women with acne or hirsutism had an odds ratio 12.5 (95%CI = 5.2-25.5) times and 36 (95%CI = 12.9-99.5) times more likely to have hyperandrogenemia than those without acne or hirsutism. The main findings of this study were the following: Hyperandrogenemic women were more likely to have oligomenorrheic cycles (OR = 3.8, 95%CI = 1.5-9.9), anovulatory cycles (OR = 6.6, 95%CI = 2.8-15.4), general obesity (BMI $\ge$ 27) (OR = 6.8, 95%CI = 2.2-27.2) and central obesity (WHR $\ge$ 127) (OR = 14.5, 95%CI = 6.1-38.7) than euandrogenemic women. Hyperandrogenemic women with non-suppressible androgens had a higher mean BMI (29.3 $\pm$ 8.9) than those with suppressible androgens (27.9 $\pm$ 7.9); the converse was true for abdominal adiposity (WHR). Hyperandrogenemic women had a 2.4 odds ratio (95%CI = 1.0-6.2) for an elevated SBP and a 2.7 odds ratio (95%CI = 0.8-8.8) for elevated DBP. When age differences were accounted for, this relationship was strengthened and further strengthened when sources of androgens were controlled. When the differences in BMI were controlled, the odds ratio for elevated SBP in hyperandrogenemic women increased to 8.8 (95%CI = 1.1-69.9). When the age, the source of androgens, the amount of obesity and the type of obesity were controlled, hyperandrogenemic women had 13.5 (95%CI = 1.1-158.9) odds ratio for elevated SBP. Conclusions: In this study population, the presence of menstrual irregularities are highly predictive for the presence of elevated androgens. Women with elevated androgens have a high risk for obesity, more specifically for central obesity. The androgenemic status is an independent predictor of blood pressure elevation. It is probable that in the general population, the presence of menstrual irregularities are predictive of hyperandrogenemia. There is a great need for a population study of the prevalence of hyperandrogenemia and for longitudinal studies in hyperandrogenemic women (adrenarche to menopause) to investigate the evolution of these relationships. ^

Linkage and association of candidate obesity genes in Mexican-Americans from Starr County, Texas

Obesity and related chronic diseases represent a tremendous public health burden among Mexican Americans, a young and rapidly-expanding population. This study investigated the impact of variation within eight candidate obesity genes, which include leptin (LEP), leptin receptor (LEPR), neuropeptide Y (NPY), NPYY1 receptor (NPYY1), glucagon-like peptide-1 (GLP-1), GLP-1 receptor (GLP1R), beta-3 adrenergic receptor (β3AR), and uncoupling protein (UCP1), on variation in human obesity status and/or quantitative traits related to obesity in Mexican Americans from Starr County, Texas. The Trp64Arg polymorphism within β3AR was typed in 820 random individuals and 240 pedigrees (N = 2,044). The Arg allele frequency was significantly greater in obese versus non-obese individuals (0.20 versus 0. 15, respectively). In addition, within the random sample, the Arg allele was associated with significantly greater body weight (p = 0.031) and body mass index (BMI, p = 0.008) than the Trp allele. In the family sample, the Trp64Arg locus was also linked to percent fat (p = 0.045) but not to body weight or BMI. No linkage between obesity, diabetes, hypertension, or gallbladder disease and the Trp64Arg mutation was observed in families using affected sib pair linkage analysis or the transmission disequilibrium test. Microsatellite markers proximate to the remaining seven genes were typed in 302 individuals from 59 families. Sib pair linkage analysis provided evidence for linkage between obesity and NPY within affected sibling pairs (p = 0.042; n = 170 pairs). NPY was also linked to weight (p = 0.020), abdominal circumference (p = 0.031), hip circumference (p = 0.012), DBP (p ≤ 0.005), and a composite measure of body mass/fat (p ≤ 0.048) in all sibling pairs (n = 545 pairs). Additionally, LEP was linked to waist/hip ratio (p ≤ 0.009), total cholesterol (p ≤ 0.030), and HDL cholesterol (p ≤ 0.026), and LEPR was linked to fasting blood glucose (p ≤ 0.018) and DBP (p ≤ 0.003). Subsequent to the linkage analyses, the NPY gene was sequenced and eight variant sites identified. Two variant sites (-880I/D and 69I/D) were typed in a random sample of 914 individuals. The 880I/D variant was significantly associated with waist/hip ratio (p = 0.035) in the entire sample (N = 914) and with BMI (p = 0. 031), abdominal circumference (p = 0.044), and waist/hip ratio (p = 0.041) in a non-obese subsample (BW < 30 kg/m2, n = 594). The 69I/D variant was a rare mutation observed in only one pedigree and was not associated with obesity or body size/mass within this pedigree. Results of this study indicate that variation at or near β3AR, LEP, LEPR, and NPY may exert effects which increase obesity susceptibility and influence obesity-related measures in this population. ^