A study presented Wednesday at CHEST 2009 in San Diego, the 75th annual scientific assembly of the American College of Chest Physicians (ACCP), found that statins have beneficial effects on patients with systolic heart failure (HF), but those with diastolic HF experienced the opposite effect, including increased dyspnea, fatigue and decreased exercise tolerance.
“It is possible that statins would help patients with systolic heart failure more than patients with diastolic heart failure due to the cholesterol-lowering and anti-inflammatory effects of statins,” said Lawrence P. Cahalin, PhD, of Northeastern University in Boston.
Researchers from Northeastern University and Massachusetts General Hospital, also in Boston, retrospectively reviewed the charts of 136 patients with heart failure to examine the effect of statins on pulmonary function and exercise tolerance in patients with diastolic HF versus systolic HF.
Cahalin and colleagues compared a non-statin group of 75 patients (82 percent of whom had diastolic HF) with a statin group of 61 patients (72 percent of whom had diastolic HF). Atorvastatin (Lipitor; Bristol Myers-Squibb) was prescribed in 75 percent of the patients on statins.
The researchers found that overall pulmonary function and exercise tolerance of patients in the statin group were significantly lower than patients in the non-statin group. Further subgroup analyses revealed that pulmonary function measures in the diastolic HF statin group were 12 percent lower than pulmonary function measures in the diastolic HF non-statin group.
Furthermore, they found that the amount of exercise performed by patients with diastolic HF who were on a statin was almost 50 percent less than patients with diastolic HF not on a statin.
"Some patients with diastolic heart failure may be more prone to the adverse effect of statins on muscle. It may be that patients with particular preexisting factors will experience unfavorable results from statin therapy, including exercise intolerance, dyspnea, and fatigue," said Cahalin.
Although the pulmonary function and exercise tolerance measures in the systolic HF statin group were not significantly greater than in the systolic HF non-statin group, the pulmonary function measures were 11 to 14 percent higher, and the peak exercise tolerance measures were 2 to 7 percent higher than the pulmonary function and exercise tolerance measures of the systolic HF non-statin group, suggesting that statins did benefit patients with systolic HF.
"Not all statins are alike and not all patients are alike. Some statins are stronger than others and are likely to act differently, given particular patient characteristics, and produce different degrees of wanted and unwanted effects," said Cahalin. "In our continuing study, we hope to identify patient characteristics that are associated with favorable and less than favorable results from statin therapy."
Although the new data suggest that statins may actually worsen symptoms in patients with diastolic HF, researchers feel that the benefits of using statins in patients with systolic HF and diastolic HF outweigh the risks.
"Due to beneficial effects on lipids and other cardiovascular factors, statins are becoming a standard treatment for many patients with or without systolic or diastolic heart failure. It is likely that the use of statins for these conditions will continue to increase," said Cahalin. "However, if patients taking a statin are short of breath, fatigued, and unable to exercise or perform functional tasks, then exams of muscle strength and endurance, as well as pulmonary function and exercise tolerance, are warranted."