Loneliness predicts physical and mental health-related quality of life over 9 months among patients with coronary heart disease.

This study investigated whether loneliness would predict physical and mental health-related quality of life (HRQoL) over 9 months and examined whether medical adherence would mediate their associations in patients with coronary heart disease (CHD). The overall design is a three-wave longitudinal study. A sample of 255 outpatients with CHD was recruited from a community-based cardiac rehabilitation programme. Participants, with a mean age of 63 years, completed measures assessing loneliness, depression and physical and mental HRQoL at baseline. Medical adherence was assessed at 3 months, and physical and mental HRQoL were reassessed at 9 months. A total of 88% of participants reported moderate or high loneliness. Baseline loneliness predicted physical and mental HRQoL at 9 months after adjusting for baseline physical and mental HRQoL, respectively. The effects remained significant when depression was also adjusted. Medical adherence at 3 months partially mediated the associations of baseline loneliness with 9-month physical and mental HRQoL. Findings underline the necessity of assessing loneliness for CHD patients to promote long-term medical adherence and further improve physical and mental HRQoL.