Quality of life impacts on 16-year survival of an older ethnically diverse cohort.

OBJECTIVE: The objective of this study is to examine the prediction of mortality, over 16 years, by the domains and domain elements underlying generic measures of quality of life (QoL).
METHODS: The method used was an analysis of mortality in an older (65 + years) representative sample (N = 2130) of a multicultural community in North Manhattan. Five conventional QoL domains were measured by in-home, rater-administered, and computer-assisted questionnaire: depressed mood, pain, self-perceived health, and function and social relationships.
RESULTS: Some domain scales that qualitatively express distress, such as depressed mood and widespread pain, significantly predicted lower mortality (were protective) and felt isolation trended in that direction, whereas domains indicating quantitative limitations such as impairment of functioning in daily tasks, stair climbing, as well as social disengagements and lack of support network significantly predicted higher mortality. Domain elements also mattered; contrary to their domain predictions, increased mortality was predicted by the domain elements of somatic symptoms of depression. Self-perceived poor health reflected the predictive (higher mortality) direction of the limitations cluster.
CONCLUSIONS: The internal complexity of QoL is underscored by differential impacts of domains and elements on mortality. Clinical implications include setting distress domains as important clinical goals, whereas strengthening limiting domains could result in lengthening life and secondarily relieving distress. The relative weighting of these goals could be derived from patient preferences and clinical efficacy. Fundamental implications lie in the interaction between the person's qualitative evaluations of choices and the quantitative building of desired choices for a better QoL.