Clustering of microvascular complications in Type 1 diabetes mellitus

To describe to what extent microvascular complications exhibit clustering in persons with Type 1 diabetes, and to assess whether the presence of one complication modified the strength of the association between the other two.

We conducted a cross-sectional analysis of the electronic medical records of 2276 persons with Type 1 diabetes treated in a specialized care hospital in Denmark in 2013. We used log-linear analysis to describe associations between diabetic kidney disease, neuropathy and retinopathy and logistic regression models to quantify the magnitude of associations adjusting for potential confounders.

The median duration of diabetes was 24 years and median HbA1c was 63 mmol/mol (7.9%). We found strong indication of clustering and found no evidence that presence of one complication modified the association between the other two. In models adjusted for diabetes duration and HbA_1c, persons with neuropathy had an OR of 2.15 (95% CI: 1.73-2.66) for concurrent diabetic kidney disease. Those with retinopathy had an OR of 2.49 (1.92-3.24) for diabetic kidney disease and of 2.66 (1.94-3.64) for neuropathy.

Microvascular complications in persons with Type 1 diabetes exhibit strong clustering. However, the association between any pair of complications is not modified by the presence of the third.