Change in health-related quality of life as a predictor of mortality in the older adults

Abstract

Purpose: We examined whether changes in health-related quality of life (HRQL) predict subsequent mortality among the Spanish elderly.

Methods: Prospective cohort study of 2,373 persons, representative of the Spanish population aged 60 and older. HRQL was measured in 2001 and 2003 using the SF-36 health questionnaire. Cox regression models were used to examine the association of changes in the physical and mental component summary (PCS and MCS) scores of HRQL from 2001 to 2003 with all-cause mortality through 2007.

Results: Two hundred twelve deaths were ascertained from 2003 to 2007. The hazard ratios for mortality across categories of PCS change were as follows: 2.12 (95% confidence interval [CI] 1.39-3.24) for a > 10-point decline; 1.51 (1.01-2.28) for a 6- to 10-point decline; 1 for the reference category, a change of -5 to +5 points; 0.83 (0.51-1.34) for a 6- to 9-point improvement and 0.68 (0.42-1.09) for a > 10-point improvement; P for linear trend <0.001. The associations between changes in the MCS and mortality showed the same direction, but were of a lower magnitude and attained statistical significance (P < 0.05) only for a > 10-point decline in MCS.

Conclusions: Changes in HRQL predict mortality in the older adults. A decline in HRQL should alert to a worse vital prognosis and stimulate the search for the possible determinants of such decline.