Prevalence of gestational diabetes mellitus among Swampy Cree women in Moose Factory, James Bay.

BACKGROUND Although high rates of gestational diabetes mellitus have been documented in native populations, few studies have examined rates of the disease among native Indians in Canada. The authors conducted a study to estimate the prevalence of gestational diabetes among Swampy Cree women, to identify factors predictive of the occurrence of gestational diabetes, and to identify delivery and infant outcomes related to the presence of the disease. METHODS Information on Swampy Cree women who gave birth at Weeneebayko Hospital, Moose Factory, James Bay, Ont., between 1987 and 1995 was obtained from medical charts. Patients with and without gestational diabetes were compared. Logistic regression analysis was used to identify independent predictors of gestational diabetes. Delivery and infant outcomes that occurred secondary to gestational diabetes were also identified by means of logistic regression. RESULTS A total of 1401 deliveries occurred at Weeneebayko Hospital over the study period, of which 1298 were included in the study. Gestational diabetes was diagnosed in 110 (8.5% [95% confidence interval (CI) 6.9%-9.9%]) of the 1298 pregnancies. Factors predictive of gestational diabetes were age 35 years or more (relative risk [RR] 4.1, 95% CI 1.5-11.7), a history of gestational diabetes in a previous pregnancy (RR 6.4, 95% CI 3.5-11.7), diastolic blood pressure of 80 mm Hg or higher at the first prenatal visit (RR 1.7, 95% CI 1.1-2.8), weight greater than 80 kg at the first prenatal visit (RR 4.9, 95% CI 1.8-12.9) and having a first-degree relative with diabetes (RR 3.0, 95% CI 1.4-6.1). The only delivery outcome independently associated with the presence of gestational diabetes was an increased likelihood of needing assisted delivery (forceps or vacuum extraction) (RR 2.8, 95% CI 1.1-7.0). Shoulder dystocia was indirectly associated with gestational diabetes owing to increased infant birth weight. Infant outcomes associated with the presence of gestational diabetes were birth weight greater than 4500 g (RR 2.4, 95% CI 1.4-3.8), hyperbilirubinemia (RR 2.9, 95% CI 1.4-6.1), hypoglycemia (RR 7.3, 95% CI 3.7-14.4) and hypocalcemia (RR 8.9, 95% CI 2.3-33.7). INTERPRETATION Gestational diabetes occurred in a significant minority of Swampy Cree women and was associated with a number of adverse outcomes.