Is postural dysfunction related to sarcopenia? A population-based study

Postural dysfunction is one of the most common community health symptoms and frequent chief complaints in hospitals. Sarcopenia is a syndrome characterized by degenerative loss of skeletal muscle mass, muscle quality, and muscle strength, and is the main contributor to musculoskeletal impairment in the elderly. Previous studies reported that loss of muscle mass is associated with a loss of diverse functional abilities. Meanwhile, there have been limited studies concerning postural dysfunction among older adults with sarcopenia. Although sarcopenia is primarily a disease of the elderly, its development may be associated with conditions that are not exclusively seen in older persons. Also, recent studies recognize that sarcopenia may begin to develop earlier in life. The objective of this paper was to investigate the association between the prevalence of sarcopenia and postural dysfunction in a wide age range of adults using data from a nationally representative cohort study in Korea. Korean National Health & Nutrition Exhibition Survey V (KNHANES V, 2010-2012) data from the fifth cross-sectional survey of the South Korean population performed by the Korean Ministry of Health and Welfare were used. Appendicular skeletal muscle mass (ASM)/height (ht)2 was used to define sarcopenia, and the Modified Romberg test using a foam pad ("foam balance test") was performed to evaluate postural dysfunction. ASM/ht2 was lower in women and significantly decreased with age in men. Subjects with sarcopenia were significantly more likely to fail the foam balance test, regardless of sex and age. Regression analysis showed a significant relationship between sarcopenia and postural dysfunction (OR: 2.544, 95% CI: 1.683-3.846, p<0.001). Multivariate regression analysis revealed that sarcopenia (OR: 1.747, 95% CI: 1.120-2.720, p = 0.014) and age (OR: 1.131, 95% CI: 1.105-1.158, p<0.001) are independent risk factors for postural instability. In middle age subjects, the adjusted OR for sarcopenia was 3.344 (95% CI: 1.350-8.285) (p = 0.009). The prevalence of postural dysfunction is higher in sarcopenia patients, independent of sex and age.