How much are upper or lower extremity disabilities associated with general health status in the elderly?

BACKGROUND: Musculoskeletal complaints influence general health status, but the relative contribution of concurrent upper and lower extremity disabilities on patient perceptions of general health is unclear. QUESTIONS/PURPOSES: We evaluated whether two regional instruments (DASH and WOMAC) reflect a patient's perception of general health measured using the SF-36 and determined whether general health components are explained by upper and lower extremity disabilities.
METHODS: We recruited 272 randomly chosen participants 65 years or older without a history of surgery for musculoskeletal disease or trauma who participated in the Korean Longitudinal Study on Health and Aging. Upper extremity disability was determined with the DASH score and lower extremity disability with the WOMAC; as a measure of general health, we obtained SF-36 scores. Multivariate regression modeling was used to assess the relative contributions made by upper and lower extremity disabilities to general health.
RESULTS: The DASH and WOMAC each was correlated with the physical component summary (PCS) scale and with the mental component summary (MCS) scale to differing extents. Multivariate regression analyses revealed that WOMAC alone, DASH alone, and WOMAC and DASH accounted for 24%, 19%, and 26% of the variance in the PCS scale. However, only the DASH was associated with the MCS scale but accounted for only 2% of the variance.
CONCLUSIONS: We found that in a community-based elderly population, perceived general physical health is associated with upper and lower extremity disabilities, whereas perceived general mental health is associated with only upper extremity disabilities, but to a small extent. LEVEL OF EVIDENCE: Level II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.