Association between physical and mental health-related quality of life and adverse outcomes; A retrospective cohort study of 5,272 Scottish adults

Abstract

Background: Health-related quality of life (HRQoL) is associated with adverse outcomes in disease-specific populations This study examines whether it is also independent predictor of incident cancer, coronary heart disease (CHD) an mortality in the general population Methods: The records of adult participants in the Scottish Health Survey 2003 were linked with hospital admissions cancer registrations and death certificates. Cox proportional hazard models were used to explore the association between quintiles of physical and mental component summary score (PCS and MCS respectively) of the SF-12 an adverse outcomes. Higher quintiles of both PCS and MCS indicate better health status Results: Among the 5,272 study participants, the mean PCS score was 49 (standard deviation (SD) 10.3). Participant were followed-up for a mean of 7.6 years. On survival analysis the lowest quintile of PCS was a strong predictor o all-cause death (hazard ratio (HR) 2.81, 95% CI 1.76, 4.49), incident cancer (HR 1.63, 95% CI 1.10, 2.42), and CHD event (HR 1.99, 95% CI 1.00, 3.96), compared to the highest quintile. This association was independent of adiposity and othe confounders. The mean MCS score 52 (SD 8.8). MCS quintile was not associated with incident cancer and CHD, and th association between MCS and all-cause death (HR 1.33, 95% CI 1.01, 1.75) became non-significant after adjustment fo adiposity Conclusion: Physical HRQoL is a significant predictor of a range of adverse outcomes, even after adjustment fo adiposity and other confounders. This study highlights the importance of perceived health in the general population.