Prevalence, incidence, and risk factors of lacunar infarcts in a community sample

Lacunar infarcts are small cavitated lesions no larger than 2 cm in diameter. Although often asymptomatic, they have been suggested as an important pathologic substrate of vascular dementia. The prevalence and risk factor profile of lacunar infarction has been variously reported, but the incidence data are scarce for large community-based data.

Participants (n = 477) were recruited randomly from the electoral roll of community residents aged 60-64 years as part of the PATH Through Life Study. Demographic information and risk factor data were collected and MRI brain scans performed in two waves, 4 years apart. The number and locations of lacunar infarcts as well as other volumetric data were assessed on T1-weighted and T2-weighted fluid-attenuated inversion recovery images.

In wave 1, 37 (7.8%) participants had at least one lacunar infarct. New lacunar infarcts were detected in 6 (6/375, 1.6%) participants at wave 2. Lacunes present at wave 1 increased significantly in mean volume from 53.90 to 69.86 mm(3) over 4 years. Hypertension (odds ratio [OR] = 1.6; 95% confidence interval [CI] = 1.01-2.60), anterior ventricle-brain ratio (%) (OR = 1.02; CI = 1.003-1.036), and volume of white matter hyperintensities (OR = 4.9; CI = 1.53-15.80) were independently associated with the prevalence of lacunar infarction.

Lacunes were common incidental findings in the brains of individuals in their 60s, and their prevalence as well as size increased with age. Hypertension was the major treatable risk factor, and lacunar infarction was usually associated with severe white matter hyperintensities on T2-weighted imaging.