Body mass index and white matter lesions in elderly women. An 18-year longitudinal study

Background: We investigated the longitudinal relationship between body mass index (BMI), a major vascular risk factor, and white matter lesions (WMLs) in older women. Methods: Twenty-seven Swedish women were followed from age 70 to 88. Measurements of BMI, and systolic and diastolic blood pressures were conducted at 70, 75, 79, 85, and 88 years. WMLs were measured using computerized tomography at age 85 and 88 (85/88). Results: Women with any WMLs at age 85/88 had higher BMI at age 70 (p = 0.003) and 75 (p = 0.006), compared to women without WMLs. Increasing severity of WMLs was related to BMI at age 70 (p < 0.001), 75 (p < 0.001), 79 (p = 0.017), and 85 (p = 0.025). After consideration of other vascular factors, BMI at age 70, 75, and 79 was most significantly related to WML at 85/88. Every 1.0 kg/m² increase in BMI at age 70 increased risk of WMLs twofold. Conclusions: Overweight and obesity may be important contributors to the presence of WMLs in the elderly.