Multimorbidity (the co-existence of two or more long-term conditions (LTCs)) is highly prevalent in people with rheumatoid arthritis (RA). This work systematically reviewed the literature to determine the effect of multimorbidity on all-cause mortality, functional status and quality of life in RA.
Six electronic databases were searched: CINAHL, Cochrane Library, Embase, Medline, PsycINFO and Scopus. Full-text longitudinal observational studies in English were selected. Quality appraisal of studies was undertaken using the Cochrane-developed QUIPS tool and a narrative synthesis of findings conducted.
5,343 papers were identified by the search strategy, with 19 studies meeting the inclusion criteria. Nine studies had mortality as an outcome, nine reported functional status and/or quality of life and one study reported both mortality and functional status. The number of participants ranged from 183-18,485, with studies conducted between 1985-2018. Mean age of participants ranged from 53.5-66.6 years; with 60.0-84.2% female. Nine studies reported a significant association between multimorbidity and higher risk of mortality in people with RA. Ten studies reported significant associations between multimorbidity and reduced functional status in RA. Three studies also reported a further association with reduced quality of life. Only one study investigated the influence of mental health comorbidities on outcomes.
Our review findings indicate that multimorbidity is a significant predictor for higher mortality and poorer functional status/quality of life in people with RA and should be considered in clinical management plans.