Association between Bone Metabolism and Vestibular Problems in the Modified Romberg Test: Data from the 2009–2010 Korean National Health and Nutrition Examination Survey

Osteoporosis contributes to the occurrence of falling and vestibular problems, particularly in elderly patients. This study aimed to investigate the association between bone metabolism with vestibular problems and falling. A total of 4054 participants of the Korean National Health and Nutrition Examination Survey (KNHANES) from 2009 to 2010 aged ≥50 years old were surveyed on their history of falling, vestibular problems evaluated by the modified Romberg test, variables involving bone metabolism, and serum levels of vitamin D and alkaline phosphatase. They also underwent dual energy X-ray absorptiometry. The crude (simple) and adjusted odd ratios (ORs) of variables involving bone metabolism for vestibular problems in the modified Romberg test and falling were analyzed using a logistic regression model. A subgroup analysis was performed according to sex and the presence of menopause in females. Vestibular problems in the modified Romberg test group but not the falling group were associated with decreased serum vitamin D levels (p < 0.001; odds ratio (OR) = 0.951; 95% confidence interval (CI), 0.926–0.976). In subgroup analysis according to sex, the post-menopause group showed a higher rate of vestibular problems in the modified Romberg test compared to the pre-menopause group (4.5% vs. 0.7%, p = 0.019). In the post-menopause group, osteoporosis was positively associated with vestibular problems in the modified Romberg test (p = 0.001, OR = 10.971, 95% CI = 2.650–45.414). On the other hand, a history of hormone replacement therapy was negatively related with vestibular problems in this subgroup (p = 0.035; OR = 0.473; 95% CI = 0.239–0.948). A decrease in serum vitamin D levels may impact the vestibular system through neural signaling or by osteoporotic changes of the otic capsule, as well as otolith particles. Decreased estrogen levels in postmenopausal women may make them more prone to osteoporotic changes, which were associated with vestibular problems in the modified Romberg test. Because this is a cross-sectional study, the causal relationship of bone metabolism with vestibular function needs to be investigated.