23 Oct Stroke in Type I Diabetes with Nephropathy, Retinopathy
MedicalResearch.com Interview with:
Stefanie Hägg, MB
Folkhälsan Institute of Genetics, Folkhälsan Research Center,
Division of Nephrology, Department of Medicine, Helsinki University
Central Hospital, Helsinki, Finland
MedicalResearch.com: What are the main findings of the study?
Answer: We studied the incidence of stroke in a large cohort of patients with type 1 diabetes in Finland. During 36,680 person-years of follow-up, we found that the incidence of total stroke, and the subtypes cerebral infarction and cerebral hemorrhage was 406, 286, and 120 per 100,000 person-years, respectively, which is higher than in the Finnish general population, for whom the incidence of stroke varies between 135 and 236 per 100,000 person years. Furthermore, we studied the impact of two diabetic microvascular complications, diabetic nephropathy and severe diabetic retinopathy, on the risk of stroke, as well as for the subtypes of stroke. The incidence of stroke, cerebral infarction, and cerebral hemorrhage increased with both the presence of severe diabetic retinopathy and with advancing diabetic nephropathy. Furthermore, we found that both diabetic nephropathy and severe diabetic retinopathy increased the risk for all subtypes of stroke, independently of traditional risk factors. A novel finding was that already incipient diabetic nephropathy (microalbuminuria) increased the risk of stroke, cerebral infarction, and cerebral hemorrhage more than 3-fold, compared with patients free of renal disease. The highest risk of stroke was seen in patients with end-stage renal disease.
MedicalResearch.com: Were any of the findings unexpected?
Answer: One of our hypotheses were that the microvascular diabetic complications, diabetic nephropathy and severe diabetic retinopathy, would be associated with especially lacunar infarctions, which are thought to be of microvascular origin.. To our surprise, we could not observe an overrepresentation of lacunar infarctions among patients with diabetic nephropathy and severe diabetic retinopathy. This could possibly be explained by the fact that asymptomatic microvascular lesions are common also in patients with nonlacunar infarctions. Unfortunately, due to our methodology we were not able to address this issue in further detail.
MedicalResearch.com: What should clinicians and patients take away from your report?
Answer: A novel finding was that severe diabetic retinopathy, independently from diabetic nephropathy, increased the risk of stroke. Furthermore, already when early signs of diabetic nephropathy (microalbuminuria) were present, the risk of suffering a stroke was increased. Therefore, early detection and treatment of both diabetic retinopathy and diabetic nephropathy is of great importance to possibly decrease the incidence of stroke in patients with type 1 diabetes.
MedicalResearch.com: What recommendations do you have for future research as a result of this study?
Answer: Although stroke is a devastating complication of diabetes, studies on stroke in type 1 diabetes are very limited. In this study we demonstrated that the two diabetic microvascular complications diabetic retinopathy and diabetic nephropathy increased the risk of stroke. Other independent risk factors are, however, largely unexplored. Therefore, in future research, we aim to study these risk factors in further detail.