Medical history and the risk of alzheimer’s disease: A collaborativere-analysis of case-control studies

In a re-analysis of eight case-control studies on Alzheimer’s disease we explored several medical conditions that had previously been suggested as possible risk factors for Alzheimer’s disease. History of hypothyroidism was increasedin cases as compared to controls (relative risk 2.3; 95% confidence interval 1.0-5.4). Severe headaches and migrainewere inversely related to Alzheimer’s disease (relative risk 0.7; 95% confidence interval 0.5-1.0). More cases than controls reported epilepsy before onset of Alzheimer’s disease (relative risk 1.6; 95% confidence interval 0.7-3.5), especially for epilepsy with an onset within 10 years of onset of dementia. Neurotropic viruses, allergic conditions, generalanaesthesia and blood transfusions were not associated with Alzheimer’s disease.