Diabetic complications in women with type 2 diabetes and polycystic ovary syndrome.

Objective: To investigate whether increased prevalence of type 2 diabetes (T2DM) in women with polycystic ovary syndrome (PCOS) translates into increased risk of diabetic complications.

Design: A cohort study based on the nationwide Diabetes in Finland database. The main analysis included 1288 women with PCOS and T2DM and 177 555 women with T2DM without PCOS (controls). Moreover, a sub-analysis that compared each woman with PCOS and T2DM to 5 controls with matching diagnosis date of T2DM and the age at onset of T2DM was conducted.

Methods: The risk for diabetic complications (ie, a composite variable including retinopathy, neuropathy, nephropathy, cardiovascular, cerebrovascular or foot complications, and all-cause death) during the period 1996-2017 was analyzed using Cox regression with PCOS as the time-dependent variable and adjustment for education level, year of T2DM diagnosis, and age at T2DM diagnosis. The unadjusted cumulative incidence of diabetic complications was calculated among women with PCOS and matched controls.

Results: The median age at T2DM diagnosis was significantly lower in women with PCOS compared with controls (33 [25th; 75th percentiles: 25; 41] versus 62 [53; 71] years). The 20-year cumulative incidence of diabetic complication after T2DM diagnosis was 35% in women with PCOS and 48% in matched controls. Women with PCOS had a smaller adjusted hazard ratio (0.70, 95% CI, 0.60-0.82) for diabetic complication.

Conclusions: The findings of the present register study suggest that PCOS does not seem to increase the risk of diabetic complications. However, studies with longer follow-up and clinical data, such as body mass index, are needed to verify this.