Heart failure severity scoring system and medical- and health-related quality-of-life outcomes: the HEMO study.

ABSTRACT

BACKGROUND: Cardiac disease is the leading cause of death in US prevalent hemodialysis (HD) patients. There is a lack of data about the impact of the severity of heart failure (HF) on outcomes and health-related quality of life (HRQoL) in HD patients. We aimed to determine the prognostic importance of the Index of Disease Severity (IDS) of the Index of Coexistent Disease (ICED) scoring system as an HF severity measure. STUDY DESIGN: Subanalysis of the Hemodialysis (HEMO) Study, a randomized controlled trial. Relationships between HF severity and mortality and cardiac hospitalizations were determined using Cox proportional hazards models. The relationship between HF severity and HRQoL scores was modeled using linear regression and generalized estimating equations. SETTING & PARTICIPANTS: 1,846 long-term HD patients at 15 clinical centers including 72 dialysis units. PREDICTOR OR FACTOR HF severity classified using the IDS of the ICED scoring system. OUTCOMES: Mortality (all cause and cause specific), cardiac hospitalizations, and HRQoL. MEASUREMENTS All-cause, cardiac, and infectious deaths; cardiac hospitalizations; and HRQoL scores from the Kidney Disease Quality of Life-Long Form. RESULTS: HF was present in 40% of HD patients. Increasing severity of HF was associated with older age, greater likelihood of diabetes, and lower serum albumin level (all P < 0.001). Adjusted HRs for all-cause mortality were 1.31 (95% CI, 1.12-1.53), 1.48 (95% CI, 1.19-1.85), and 2.11 (95% CI, 1.43-3.11) for mild, moderate, and severe HF, respectively (P < 0.001). All-cause, cardiac, and infectious mortality and cardiac hospitalizations increased with increasing severity of HF. Increasing HF severity was associated with decreases in HRQoL, particularly in physical functioning and sleep quality. LIMITATIONS: This study is limited by the small sample size in the most severe HF group. CONCLUSIONS: Increasing severity of HF is associated with increased mortality and cardiac hospitalizations and worse HRQoL, especially in perceived physical limitations. These findings emphasize the utility of the IDS of the ICED score as a valid prognostic tool for medical and HRQoL outcomes in the HD population with HF.