Distinct associations between bone mineral density and severity of white matter hyperintensities of presumed vascular origin in older men and women. The three villages study

Summary : In a rural cohort of older adults, osteoporosis was associated with moderate-to-severe white matter hyperintensities of presumed vascular origin in men but not women. This association was influenced by age and diet. Study results underscore potential sex-specific cerebrovascular implications of low bone mineral density. Objectives: This study aimed to assess the association between bone mineral density (BMD) and white matter hyperintensities (WMH) of presumed vascular origin in men and women aged ≥ 60 years living in rural settings. Methods: Following a population-based cross-sectional design, participants received dual-energy x-ray absorptiometry to estimate bone health, and a brain MRI to grade WMH severity. Logistic regression models, adjusted for relevant confounders, were fitted to assess the association between categories of BMD (normal, osteopenia and osteoporosis), as well as the continuous BMD value, and the presence of moderate-to-severe WMH. Results: The study included 399 participants (mean age 68.8 ± 6.8 years; 42% men). A total of 94 (24%) individuals had normal BMD T-scores, 149 (37%) had osteopenia, and 156 (39%) had osteoporosis. Moderate-to-severe WMH were detected in 88 (22%) cases. Logistic regression models, adjusted for the above-mentioned covariates, showed no significant association between categories of BMD and WMH severity in the total population. When men and women were modeled separately, the association between osteoporosis and moderate-to-severe WMH became significant for men (OR: 7.15; 95% C.I.: 1.13 – 45.3), but not for women. Parsimonious models showed that covariates driving this association significant were the combination of age and diet (OR: 6.41; 95% C.I.: 1.04 – 39.7). Similar findings were noted when BMD was treated as a continuous variable. Conclusion: Osteoporosis is associated with a higher prevalence of moderate-to-severe WMH in older men living in a population of frequent fish consumers. Increasing age and an unhealthy diet contributed significantly to this association.