Do stressful life events cause type 1 diabetes?

BACKGROUND The link between psychological stresses and deteriorating diabetes control is well known. However, people who develop type 1 diabetes sometimes ascribe the onset of diabetes to a recent stressful event. AIMS To perform a systematic review of the literature to assess whether stressful life events can cause type 1 diabetes. METHOD Electronic and manual literature search using appropriate key words. RESULTS Older literature provides anecdotal links between stressful life events and diabetes. The difficulty in interpreting these papers is the small numbers under study and the lack of distinction between type 1 and type 2 diabetes. More recent studies, in particular from Scandinavia, demonstrate that there is no link between either the number or the severity of life events in the year up to the diagnosis and the onset of the condition. CONCLUSION Given the progress in understanding the molecular biology of diabetes, the concept that stress causes type 1 diabetes is no longer plausible. There is no evidence from large well-controlled trials that type 1 diabetes is caused by stressful life events.