The impact of comorbidities on health-related quality of life of people with osteoarthritis over 10 years

Abstract

To investigate the impact of total number and patterns of comorbidities on health-related quality of life (HRQoL) and identify the most prevalent and influential comorbidity patterns in people with osteoarthritis (OA) over ten years. Participants from the Tasmanian Older Adult Cohort aged 50-80 years, with self-reported OA and data on comorbidities and HRQoL were included. Participants were interviewed at baseline (n = 398), 2.5-years (n = 304), 5-years (n = 269) and 10-years (n = 191). Data on the self-reported presence of 10 chronic comorbidities were collected at baseline. HRQoL was assessed using the Assessment of Quality of Life-4-Dimensions. The long-term impacts of the number and of the nine most prevalent combinations of cardiovascular (CVD), non-OA musculoskeletal (Ms), metabolic, and respiratory comorbidities on HRQoL over ten years were analysed using linear mixed regressions. Compared with comorbidity-free OA participants, the health state utility (HSU) of those with 2 or ≥ 3 comorbidities was respectively -0.07 and -0.13 units lower over ten years, largely driven by reduced scores for independent living, social relationships and psychological wellness. Comorbidity patterns including 'CVD+Ms' were most influential, and associated with up to 0.13 units lower HSU, mostly through negative impacts on independent living (up to -0.12), psychological wellness (up to -0.08) and social relationship (up to -0.06). Having more comorbidities negatively impacted OA patients' long-term HRQoL. OA patients with CVD and non-OA musculoskeletal conditions had the largest HSU impairment, therefore optimal management and prevention of these conditions may yield improvements in OA patients' HRQoL.