Adherence to guidelines is a predictor of outcome in chronic heart failure: the MAHLER survey

The impact on outcome of the implementation of European guidelines for the treatment of chronic heart failure (CHF) has not been evaluated. We investigated the consequences of adherence to care by cardiologists on the rate of CHF and cardiovascular (CV) hospitalizations and time to CV hospitalization.

We constructed class adherence indicators for angiotensin-converting enzyme (ACE)-inhibitors, beta-blockers, spironolactone, diuretics, and cardiac glycosides and GAIs (GAI3 adherence to first three classes of heart failure medication, GAI5 adherence to five classes). In the study, 1410 evaluable patients (mean age 69, 69% males, New York Heart Association (NYHA) II: 64%, III: 34%, IV: 2%) were enrolled and followed up for 6 months by 150 randomly selected cardiologists/cardiology departments from six European countries (France, Germany, Italy, The Netherlands, Spain, and UK). Overall, adherence to treatment guidelines was 60 (GAI3) and 63% (GAI5) and was better for ACE-I (88%) or diuretics (82%) than for cardiac glycosides (52%), beta-blockers (58%), and spironolactone (36%). In the three tertiles of the population defined by a decreasing mean adherence score value, CHF and CV hospitalization rates were, respectively, 6.7, 9.7, and 14.7% and 11.2, 15.9, and 20.6% (P<0.002 and P<0.001, respectively). Global adherence indicator GAI3 was an independent predictor of time to CV hospitalization in a multi-variable model together with NYHA Class, history of CHF hospitalization, ischaemic aetiology, diabetes mellitus, and hypertension.

We demonstrate that adherence of physicians to treatment guidelines is a strong predictor of fewer CV hospitalizations in actual practice. There is a need to develop further quality improvement programmes in this condition.