HORMONAL STATUS AND NIDDM IN THE EUROPEAN AND MELANESIAN POPULATIONS OF NEW-CALEDONIA - A CASE-CONTROL STUDY

OBJECTIVE: To assess ethnic differences in androgenic status related t o non insulin-dependent diabetes mellitus (NIDDM) in male and female M elanesians and Europeans of New Caledonia. DESIGN: This is a case-cont rol study nested in a prevalence study for diabetes mellitus in the mu ltiracial population of New Caledonia. SUBJECTS: 186 male subjects wer e included in the survey (77 Melanesians and 16 Europeans in each case and control group). Each case and control group included 104 female M elanesian subjects (69 premenopausal and 35 postmenopausal). METHODS: Diabetic subjects were matched for age, gender, ethnic group and locat ion, with healthy normoglycaemic subjects. Testosterone levels in men and sex hormone-binding globulin (SHBG) levels in women (measured by r adioimmunoassay, RIA) were compared between NIDDM and control subjects in relation to obesity, central adiposity and insulin levels. RESULTS : In both ethnic groups, NIDDM was associated with lower testosterone levels but there was a marked difference among Europeans. Testosterone was negatively associated with the body mass index (BMI) (r = -0.35, P < 0.01) and fasting insulin (r = -0.37, P < 0.001) in control Melane sians only. In Melanesian women, NIDDM was associated with lower SHBG levels in pre- and postmenopausal women (P < 0.001). SHBG mean level w as not associated with menopausal status.CONCLUSION: Our results confi rm in a Pacific population that NIDDM is associated with low levels of testosterone in men and low levels in SHBG in women. In contrast to w hite populations, Melanesian women have a more androgenic profile, wha tever their menopausal status.