[Estimating prevalent microvascular complications of diabetes mellitus in Germany. Analysis of statutory health insurance data in 2012 and 2013].

Background: Data sources for the systematic and ongoing analysis of prevalence of microvascular complications of diabetes mellitus are limited in Germany. For the first time, we estimated the complications prevalence based on claims data of all statutory health insurance (SHI) providers according to the Data Transparency Act.

Methods: Health claims data of the reporting years 2012 and 2013 were analyzed. The reference population was identified as insured persons with a diabetes diagnosis according to the international classification of disease. Diabetes was defined as documentation of at least two confirmed diabetes diagnoses in an outpatient setting or one diagnosis in an inpatient setting (ICD codes E10-E14). Complications were defined based on the following ICD codes: nephropathy (N08.3), retinopathy (H36.0), polyneuropathy (G63.2), diabetic foot syndrome (DFS; E10-14.74, E10-14.75), chronic kidney disease (N18.-), and treatment with dialysis (Z49.1, Z49.2, Z99.2). Results were compared to prevalence estimates based on routine data and registries in Germany and abroad.

Results: In 2013, diabetes was documented for 6.6 million persons with SHI (2012: 6.5 million). In 2013, chronic kidney disease (15.0%) was the most frequent complication, followed by diabetic polyneuropathy (13.5%), nephropathy (7.6%), retinopathy (7.0%), DFS (6.1%), and treatment with dialysis (0.56%). While results for diabetic retinopathy, nephropathy, and polyneuropathy are lower than prevalence estimates from other type 2 diabetes studies, they are comparable for chronic kidney disease, treatment with dialysis, and DFS.

Conclusion: Continuous analysis of health claims data is highly valuable for the diabetes surveillance. However, detailed analyses are required for verification and harmonization of case definitions and documentation practice.