Association of Charlson Comorbidity Index with Clinical Characteristics and Outcomes in Heart Failure

BACKGROUND: The Charlson comorbidity index (CCI) is a validated weighted measure of comorbidity burden, but has an unclear role in heart failure (HF). OBJECTIVES: To characterize age-adjusted CCI (ACCI) in HF, its association with the use of guideline-directed medical therapy (GDMT) and with outcomes. METHODS: In the Swedish HF registry, patients were divided into 3 groups based on ACCI scores (low 1-3, intermediate 4-6, and high ≥7). We studied its association with clinical characteristics and GDMT use. Multivariable multinominal and Cox regressions were used to analyze ACCI and its association with ejection fraction (EF) category (reduced [HFrEF], mildly reduced [HFmrEF], preserved [HFpEF]), and with outcomes up to 3 years. RESULTS: Among 117,419 patients (age 75 [66-82], 36% women, 53% HFrEF, 24% HFmrEF, 23% HFpEF, median ACCI was 5, 6 and 6 respectively. ACCI ≥7 was present in 31% with HFrEF, 35% with HFmrEF and 42% with HFpEF. A higher ACCI score was associated with higher EF category, NYHA class, serum NT-proBNP, diuretic use, and lower quality of life and GDMT use (p<0.05 for all). The risk of composite CV mortality/first HF hospitalization was higher with intermediate (adjusted HR 1.34, 95% CI 1.29-1.39) and high vs low ACCI (1.76, 1.69-1.83). High ACCI category (vs low) was significantly associated with non-CV (adjusted HR 6.36, 95% CI 5.75-7.04), but also, CV mortality (4.35, 3.99-4.74), and total hospitalizations (adjusted IRR 2.16, 2.11-2.22) but also HF hospitalizations 1.23 (1.17-1.28). CONCLUSION: The ACCI discriminates well in HF, with higher ACCI being associated with greater severity of HF, lesser GDMT use and worse quality of life. Higher ACCI was more strongly associated with death than hospitalization. Higher ACCI was more strongly associated with non-CV outcomes but also with CV and HF outcomes.