Background
Frailty and depression are highly prevalent in haemodialysis recipients, exhibit a reciprocal relationship, and are associated with increased mortality, hospitalisation, and lower quality of life. Despite this, there has been little exploration of the relationship between depression and frailty upon patient outcomes. We aimed to explore the relationship between depression and frailty and their associations with mortality, hospitalisation, and quality of life (QOL).
Methods
We performed a prospective cohort study of prevalent haemodialysis recipients linked to national datasets for outcomes including mortality and hospitalisation. Depression was assessed using PHQ-9, frailty using Clinical Frailty Scale (CFS), and quality of life using EuroQol EQ-5D Summary Index.
Results
485 prevalent haemodialysis recipients were recruited, with 111 deaths and 1241 hospitalisations during follow-up. CFS was independently associated with mortality (HR 1.31; 95% C.I. 1.08, 1.59; P = 0.006), hospitalisation (IRR 1.13; 95% C.I. 1.03, 1.25; P = 0.010), and lower QOL (Coef. -0.401; 95% C.I. -0.511, -0.292; P<0.001). PHQ-9 score was independently associated with lower QOL (Coef. -0.042; 95% C.I. -0.063, -0.021; P<0.001), but not mortality (HR 1.00; 95% C.I. 0.96, 1.04; P = 0.901), or hospitalisation (IRR 0.99; 95% C.I. 0.97, 1.01; P = 0.351). In an adjusted model including CFS, moderate depression was associated with reduced hospitalisation (IRR 0.72; 95% C.I. 0.56, 0.93; P = 0.013).
Conclusions
With addition of frailty, depression was associated with lower hospital admissions, but poorer quality of life. The relationship between frailty and depression, and their influence on outcomes is complex, requiring further study.