Measuring subjective wellbeing in patients with heart disease: relationship and comparison between health-related quality of life instruments.

PURPOSES

This study aimed to validate the use of subjective wellbeing (SWB) in patients with heart disease, to explore the complementary vs substitute relationship between SWB and health status utility (HSU), and to reveal which life domains matter for patients with heart disease compared to healthy persons.

METHODS

Data were obtained from a large multi-national, multi-instrument comparison survey. Subjective wellbeing instruments (ONS4, PWI, SWLS), health status utility instruments (15D, AQoL-8D, EQ-5D-5L, HUI3 and SF-6D) and a disease-specific quality of life instrument (MacNew) were administered among patients with heart disease (N = 943). Validity and sensitivity of SWBs were studied. Exploratory factor analysis (EFA) was performed to examine the difference in descriptive systems between the SWB, HSU and MacNew. The importance of life domain satisfaction in explaining overall life satisfaction was investigated using regression analysis.

RESULTS

The known-group analysis showed that both SWB and HSU scores differed according to changes in the severity of heart disease. EFA showed that SWB and HSU were generally complementary instruments. The life domains that were significantly important to patients with heart disease were standard of living, followed by achieving in life, personal relationships, personal health, and future security. Compared to the healthy public, personal health and future security were significantly more important life domains.

CONCLUSIONS

Assessing SWB provides complementary information on understanding heart patients' subjective outcome over the use of quality of life instruments alone. Given the adverse psychological impact of heart disease, addressing the important domain revealed by SWB assessment in management planning should be considered.