Predictors of Health Related Quality of Life in Adults 50 Years and Older

Background: Perceived health related quality of life (HRQoL) and measures of physical function are consistently measured to evaluate the effectiveness of interventions. In older adults there are numerous measures of physical function. Purpose: To determine which measures of physical function are most closely associated with HRQoL in adults 50 years of age and older. Methods: 64 participants (54-93 years of age) completed assessments of HRQoL (Short Form Health Survey, Version 2 (SF-12v2 ) and World Health Organization Quality of Life-BREF (WHOQOL BREF)) and questionnaires related to self-esteem and physical activity. Participants were also assessed for six minute walk distance (6MWD), muscle strength, balance, gait, and lower extremity function (Short Performance Physical Battery; SPPB). Correlation analysis was performed between and within all dependent and independent measures. Forward Stepwise-Linear regression was performed to determine which independent measures predicted dependent measures. Results: The physical component score (PCS) and the mental component score (MCS) of the SF-12v2 were independent of each other unlike the domains of the WHOQOL BREF. The independent measures were best able to predict WHOQOL Physical Health (r2 =0.60), WHOQOL Psychological Health (r2 =0.58), and PCS (r2 =0.43). SPPB score best predicted PCS and WHOQOL Physical Health. The vestibular component of balance best predicted WHOQOL Psychological Health and Social Relationships. Self- esteem helped predict MCS, WHOQOL Psychological Health, and WHOQOL Social Relationships. 6MWD, muscle strength, and specific measurements of gait did not enter into any of the predictive equations for HRQoL. Conclusion: SPPB, vestibular component of balance, and self-esteem may be important tools in assessing HRQoL in older adults.