Sex-specific differences in microvascular complication risk factors in type 1 diabetes mellitus (T1DM) remain incompletely characterized despite long-term evidence linking glycemic and cardiovascular risk factors to disease progression. A longitudinal cohort study published in Diabetes Care evaluated sex-specific associations between clinical risk factors and 30-year incidence of retinopathy and kidney outcomes in adults with T1DM.

The Pittsburgh Epidemiology of Diabetes Complications cohort included 325 women and 333 men with a mean baseline age of 27 years and mean diabetes duration of 19 years. Participants were followed from 1986-1988 through 2016-2018 for incident proliferative diabetic retinopathy (PDR), severely increased albuminuria (SIA), and chronic kidney disease stage G3 (CKD G3). Associations between longitudinal clinical risk factors and complication incidence were assessed using sex-stratified multivariable joint models in participants free of complications at baseline.

Findings

• PDR incidence was similar between women and men (57% vs 59%; P = 0.54).
• SIA incidence was lower in women than men (18% vs 25%; P = 0.10), while CKD G3 incidence was numerically higher in women (28% vs 21%; P = 0.11).
• Glycated hemoglobin (HbA1c) and blood pressure (BP) were independent risk factors for PDR in both sexes.
• For SIA, HbA1c was associated in both sexes, while triglycerides and body mass index were additional factors in women and smoking was a significant factor in men.
• For CKD G3, HbA1c remained a risk factor in both sexes, while smoking was additionally associated in men.

The analysis showed that HbA1c and BP remained important retinopathy risk factors across sexes, while kidney risk profiles differed between women and men with T1DM. These findings support further evaluation of sex-specific approaches for kidney risk reduction in T1DM.