White matter lesions as a risk factor for stroke and dementia. A population-based study in 85-year-olds

Aim. This study was performed to determine whether white matter lesions on cranial computed tomography (cCT) are associated with increased prevalence and incidence of stroke, dementia, and mortality. Methods. A representative sample of 239 85-year-olds living in Gothenburg, Sweden, was examined in a population-based study. Stroke was defined by information from patient reports, key informants, and an inpatient register system. Dementia was diagnosed according to DSM-III-R. White matter lesions (WML) and infarcts were determined by cCT. Follow-up examinations were performed 3 years later. Results. White matter lesions doubled the odds of previous stroke (OR 1.8, 95% CI 1.03-3.3). Individuals with WML and stroke showed higher prevalence of dementia (OR 16.5, 95% CI 6.5-41.8) and mortality (OR 12.4, 95% CI 5.1-30.0) than those without WMIL and stroke. Conclusion. White matter lesions are common in the elderly, and these changes have clinical consequences increasing the risk of stroke. Whether preventive mechanisms could lead to risk reduction should be clarified in further studies.