LEPTIN CONCENTRATIONS IN DIABETIC AND NONDIABETIC MEXICAN-AMERICANS

Leptin, the product of the OB gene, is increased in obese individuals, suggesting resistance to its effect. We questioned whether subjects w ith NIDDM have an altered regulation of serum leptin levels. We used a radioimmunoassay to measure serum leptin levels in three groups from the San Antonio Heart Study: 1) 50 Mexican-Americans with NIDDM; 2) 50 nondiabetic Mexican-Americans matched by age and sex to the diabetic Mexican-Americans; and 3) 50 nondiabetic Mexican-Americans matched by age, sex, and BMI to the diabetic Mexican-Americans. Leptin concentrat ions did not differ significantly by diabetic status, Leptin concentra tions were significantly correlated with BMI in all groups (NIDDM wome n: r = 0.637; nondiabetic women: r = 0.772; NIDDM men: r = 0.849; and nondiabetic men: r = 0.686; all P < 0.001), Leptin levels were higher in women than in men regardless of diabetic status. We concluded that the leptin concentrations were not different in diabetic and nondiabet ic subjects and that the association of leptin with obesity was simila r in diabetic and nondiabetic subjects.