Cortical surface areas link to fall-related fracture odds

In a bidirectional two-sample Mendelian randomization study of more than 51,000 Europeans, researchers tested whether cortical thickness or surface area across 34 brain regions genetically influences falls and simple-fall fractures. Genetically predicted surface area in two regions showed significant associations with simple-fall fractures after correction for multiple comparisons. A larger caudal anterior cingulate surface area was associated with lower fracture odds (OR 0.95, 95% CI 0.92–0.98), whereas a larger insula surface area was related to higher odds (OR 1.05, 95% CI 1.02–1.08). Associations with a broader falls or tendency-to-fall phenotype were not robust. Reverse analyses showed no evidence that falls or simple-fall fractures altered cortical traits, and exploratory analyses found that estimated bone mineral density did not support mediation.