Gestational diabetes in South African women with HIV and HIV-seronegative women: results from the ORCHID cohort.

CONTEXT: Little data exist on early and late gestational diabetes (GDM) in sub-Saharan Africa.

OBJECTIVE

We assessed the prevalence of GDM in South Africa, including early and late GDM, and investigated insulin sensitivity, 1st phase insulin secretion, and beta cell function to understand the underlying pathophysiology of glucose metabolism in early and late pregnancy.

METHODS

We enrolled women with HIV (WWH) and HIV-seronegative women at ≤18 weeks' gestation. A 75 g oral glucose tolerance test was administered at enrollment (early) and 32-36 weeks' gestation (late) to diagnose GDM using WHO criteria. Matsuda, Stumvoll, oral disposition index, and glucose sensitivity from Mari models were calculated. Logistic regression models were used to assess the association of HIV with GDM.

RESULTS

Among 1573 (n = 668 WWH) participants, median age was 28 years, gestation 13 weeks. Overall, 7.9% had GDM (6.7% WWH, 9.1% HIV-seronegative); of these, 65% had early GDM. Women with early GDM had the lowest Matsuda, Stumvoll, oral disposition index, and glucose sensitivity at enrollment compared to those with late GDM and those without GDM. In adjusted analyses, WWH had lower odds of GDM than HIV-seronegative women (adjusted odds ratio: 0.57, 95% Confidence Interval: 0.38-0.85).

CONCLUSION

GDM prevalence in South Africa is similar to North America/Europe. Early GDM was diagnosed in a large majority of women who also exhibited features of poorer insulin sensitivity and beta cell function than those diagnosed late in pregnancy or without GDM. WWH had lower GDM risk than HIV-seronegative women. Future studies to understand the implications of early GDM in African populations are warranted.