THE RELATIONSHIP OF MENSTRUAL IRREGULARITY TO TYPE-2 DIABETES IN PIMAINDIAN WOMEN

OBJECTIVE- Menstrual irregularity is associated with hyperinsulinemia and hyperandrogenemia in nondiabetic Pima Indian women of child-bearin g age. In this population-based study, we determined the relationship of menstrual irregularity to type 2 diabetes in Pima Indian women. RES EARCH DESIGN AND METHODS- Participants for this cross-sectional analys is were 695 nonpregnant Pima Indian women, aged 18-44 years, involved in an ongoing epidemiologic study of diabetes among residents of the G ila River Indian Community of Arizona. Clinical data were collected by questionnaire and an examination that included a 75-g oral glucose to lerance test; diabetes was diagnosed by World Health Organization crit eria. Menstrual irregularity was defined as an interval of 3 months or more between menses, when not pregnant, since age 18 years. RESULTS- History of menstrual irregularity was significantly associated with a high prevalence of diabetes (37 vs, 13%; odds ratio = 4.2, 95% CI = 1. 6-10.8) in the least obese women (BMI < 30 kg/m(2)), adjusted for the effects of age and overall obesity. This association was, in part, bec ause of greater central obesity in women with irregular menses. In mor e obese women, there was little association with menstrual irregularit y, and diabetes was frequent regardless of menstrual history. CONCLUSI ONS- Prevalence of type 2 diabetes is higher among Pima Indian women w ith a history of menstrual irregularity. The difference is most pronou nced among the least obese group of women. This association may be bec ause of insulin resistance and hyperinsulinemia, which predict type 2 diabetes, also causing hyperandrogenism and menstrual irregularity. Th e findings reinforce the need to evaluate women with menstrual irregul arity for hyperglycemia.