Hyperhomocysteinemia as a cardiovascular risk factor in Indian women: determinants and directionality.

OBJECTIVE: To assess Homocysteine (Hcy), vitamin B12 and folic acid (FA) concentrations in resident Indian women and to study their correlation with traditional risk factors for coronary artery disease. MATERIAL AND METHODS: The study included 137 consecutive women who attended a health care program (HCP) for women at and above 40 years of age (MAITREYI's HCP). Fasting blood samples for Hcy, B12 and folate were collected on ice, centrifuged within 1/2 hour and stored at -70 degrees C till assayed using a chemiluminescence method. All women underwent a screening for their general health profile including cardiovascular health. RESULTS: Of the 137 women screened 21 were excluded because of presence of factors known to affect Hcy levels (history of existing CAD had hypothyroidism or were on multivitamin supplements). The median Hcy, folic acid and vitamin B12 levels were 9 pmol/L (range 4.2-38.6), 8.8 ng/ml (2.3-31.6 range) and 214 pg/ml (100-2400 range) respectively. The prevalence of hyperhomocysteinemia (>15 pmol/L) was 24.2%. Correlation for continuous variables using spearman's test and for categorical variables with chi-square test showed a highly significant negative correlation with vitamin B12 (p < 0.001) and FA (p<0.002). Both systolic (p < 0.05) and diastolic (p < 0.02) and diastolic blood pressure also showed a significant correlation. However, no correlation was found between plasma Hcy and blood sugars, lipids, age, body mass index and menopausal status. The CAD risk was assessed using Framingham risk scores and this too did not show a correlation with plasma Hcy. CONCLUSIONS: A large number of women from the present study had hyperhomocysteinemia and were deficient in vitamin B12. A significant negative correlation between vitamin B12 and plasma Hcy levels was foundin these older women. Most Indian studies including the present one do not show a positive correlation between elevated Hcy levels and CAD in spite of a large percentage of persons showing elevated homocysteine levels. Since high Hcy levels are recognized as an independent risk factor for CAD, these findings of absence of correlation between Hcy and CAD as reported in various Indian studies need to be explored and explained.

Clinical, endocrine and metabolic studies in the kindred of familial partial lipodystrophy--a syndrome of insulin resistance.

OBJECTIVE: To study clinical, endocrine and metabolic profiles in the kindred of subjects with familial partial lipodystrophy (FPLD, Dunnigan type). MATERIAL AND METHODS: Twenty two relatives (10 males, 12 females), from an extended family with FPLD, were assessed for the phenotypic features, impaired glucose tolerance (IGT)/diabetes mellitus (DM), dyslipidemia and the presence of insulin resistance. Plasma glucose and serum lipids were measured using glucose oxidase and standard colorimetric methods. Serum insulin was estimated by radioimmunoassay. RESULTS: The age was 12 to 67 years, two being adolescents. Two of the 20 adults were overweight and eight were underweight; BMI (adults) was 15.5 to 28.5. Features of FPLD were evident among eight out of 12 women. This typical phenotype was not obvious in all 10 male members. Varying degree of Hirsuitism was observed in four of 12 women, acanthosis nigricans in 11 out of 22 members and skin tags were present in only eight of 22; hypertension in six members and diabetes in four. Eleven members had either impaired glucose tolerance (IGT) (n=7), or DM (n=4). Ten of 20 members showed hyperinsulinemic response on oral glucose tolerance test (OGTT). Dyslipidemia was present in 13 family members. CONCLUSION: The majority (2/3rd) of female members showed typical phenotypic features of FPLD, with a clustering of cardiovascular risk factors and insulin resistance syndrome. More than half the men without phenotypic features of FPLD had either IGT/DM, dyslipidemia, hypertension or cardiovascular disease.

Serum leptin concentrations in hyperinsulinemia in the sets of obese, lipodystrophic and/or non-obese patients.

OBJECTIVE: To study the relationship between serum leptin and circulating insulin under basal and in response to oral glucose administration in hyperinsulinemic patients with or without obesity. MATERIAL AND METHOD: Fifteen female patients of known hyperinsulinemia provided material for the study. Leptin and insulin in sera were estimated by radioimmunoassay methods. RESULTS: Eight of the 15 hyperinsulinemic patients with high body mass index (BMI) (31 +/- 0.94 kg/m2) had significantly (p < 0.01) elevated serum leptin concentrations (26.1 +/- 2 ng/ml) as compared to the levels in the remaining seven non-obese hyperinsulinemic patients with BMI of 20 +/- 1.0 kg/m2; their mean levels of serum leptin were low 5.7 +/- 1.1 ng/ml. Four of the latter group had face-sparing partial lipodystrophy. The mean circulating leptin concentrations in the control group of seven healthy normoinsulinemic and regularly menstruating women with normal BMI (19 +/- 0.95 kg/m2) were 13.7 +/- 1.8 ng/ml. DISCUSSION: The results of the present study in 15 hyperinsulinemic patients show that circulating levels of leptin are not related to serum insulin. However, there was a positive correlation with BMI. An interesting observation of the study is that, notwithstanding the normal BMI, the group of hyperinsulinemic patients with face-sparing partial lipodystrophy had the lowest levels of circulating leptin concentrations. They were closer to the values found in prepubertal girls.