Potentially modifiable correlates of functional status in patients with chronic heart failure.

Background: Chronic heart failure (CHF) patients suffer from multiple and agonizing symptoms like shortness of breath and reduced functional status, the latter of which is usually assessed using New York Heart Association (NYHA) functional class.
Purpose: In order to identify potentially modifiable factors of reduced functional status in patients with CHF, we investigated somatic and psychosocial correlates of NYHA functional class. We subsequently compared the results to correlates of left ventricular ejection fraction (LVEF) as an objective parameter of disease severity.
Methods: The cross-sectional study (n = 314) was part of the German Heart Failure Network. Data were analysed using a logistic regression modelling process.
Results: In the final regression model, NYHA functional class was only significantly associated with depression (odds ratio (OR) = 1.18; 95% confidence interval (CI) = 1.09-1.27) and multimorbidity (OR = 1.17; 95% CI = 1.04-1.32). LVEF was associated with amino-terminal pro-brain natriuretic peptide (NT-proBNP) (OR = 0.60; 95% CI = 0.44-0.82), aetiology of CHF (OR = 2.08; 95% CI = 1.11-3.90), and smoking (OR = 2.21; 95% CI = 1.25-3.91).
Conclusions: Whereas LVEF was not related to depression, our data revealed a close association between functional status (as assessed by NYHA functional class) and depression in patients with CHF, even after adjusting for cardiac and socio-demographic variables. Different forms of underlying causal mechanisms could be suspected; it appears promising to further investigate this specific interaction. In any event, pending further investigation, our results underscore the need to examine CHF patients with respect to both somatic symptom burden and potential depressive disorders.