Prognostic impact of symptoms in chronic heart failure - results from COMET

Abstract

Background:Chronic heart failure (CHF) causes distressing symptoms that are an appropriate target for therapy and may also indicate a worse prognosis. However, symptoms are often ambiguous and open for subjective interpretation. We evaluated how symptoms and signs in the COMET study impacted on prognosis for mortality and worsening heart failure. Methods: In COMET (Carvedilol Or Metoprolol European Trial) 3029 patients with CHF class II-IV were randomised to carvedilol or metoprolol and followed in average for 58 months. 16 baseline demographic variables were used in uni- and multivariate analysis. Symptoms of breathlessness, fatigue and well-being were each assessed at baseline in a 5-graded Lickert scale. Presence of pulmonary rales, oedema (none, ankle or above ankle) and third heart sound were also assessed. Results: In a univariate analysis higher scores for breathlessness, fatigue, well-being and oedema were all significantly related to poorer survival (all p<0.001) and the development of worsening heart failure. In a multivariate Cox regression analysis, including 16 baseline covariates, breathlessness remained significantly related to mortality (Risk Ratio 1.14 per unit: 95% CI 1.04 – 1.26; p=0.007). Oedema above the ankle was also associated with poor survival (p<0.01). Fatigue but not breathlessness remained a significant predictor for the development of worsening heart failure (RR 1.091 per unit; 95% CI 1.015–1.173; p=0.017). Conclusions: Common symptoms in CHF, fatigue and breathlessness, have important and independent prognostic long-term implications. Accordingly, evaluating symptoms is useful not only because they are a target for treatment but also because they are a guide to worse prognosis in patients with CHF.