Abstract
The objectives of this study were to describe the global geographic variation of microvascular and macrovascular complications in childhood onset type 1 diabetes (T1D) and to relate any such variation to diabetes care activities such as self blood glucose monitoring and intensive insulin therapy.
The DiaComp study is a multinational (17 countries) cross-sectional study of complications in T1D (n=2, 657). All participants were diagnosed at < 15 years of age and had a diabetes duration of 5-24 years when surveyed. Complications were assessed by self-report of physician diagnosis.
Twenty-two centres in 17 countries achieved at least a 67% response rate and are included in the analyses. Central European centres exhibited high rates of retinopathy (Lithuania=31. 6%, Romania=24. 2%), laser treatment (Lithuania=25. 4%) and neuropathy (Lithuania=29. 9%, Romania=12. 4%) in those with short duration of diabetes (5–15 years), as did Cuba for neuropathy (15. 4%). For retinopathy the geographic variation in the short-duration group was also pronounced, ranging from 1. 6% in Italy to 41. 6% in Lithuania, and from 0% in Brazil, Italy and Australia, to 29. 9% in Lithuania for laser treatment. Variation was less dramatic for the prevalence of complications in the long-duration group (15–25 years). Hypertension and duration were strong consistent predictors of all complications, while women had higher prevalence for half the complications (retinopathy, laser treatment and renal disease). Intensive insulin therapy and self-monitoring of blood glucose showed little association with prevalence of complications.
In conclusion, this first population-based account of the geographic variation of T1D complications has demonstrated substantial variation. However, the healthcare practice variables that were measured contributed little toward explaining this variation.