Hypocholesterolaemia and mortality in patients with coronary artery disease

Background: The association between hypocholesterolaemia and outcome of patients with coronary artery disease (CAD) remains controversial. We undertook this study to investigate whether there is an association between spontaneous or under statin therapy occurring hypocholesterolaemia and mortality in patients with CAD. Materials and Methods: This study included 14 952 patients with CAD undergoing percutaneous coronary intervention (PCI). Hypocholesterolaemia was defined as a total cholesterol (TC) <157 mg/dL (the upper limit of 1st quintile of TC). The study outcome was all-cause mortality at 30 days and 3 years after PCI. Results: Patients are categorized in four groups according to TC and statin therapy on admission: statin-naïve patients with hypocholesterolaemia (n = 1102), statin-naïve patients without hypocholesterolaemia (n = 7490), statin-treated patients with hypocholesterolaemia (n = 1824) and statin-treated patients without hypocholesterolaemia (n = 4536). In these groups, 30-day all-cause deaths occurred in 3.7%, 1.4%, 1.2% and 0.6% of the patients, respectively; 3-year deaths occurred in 18.0%, 8.4%, 10.9% and 7.2%, of the patients, respectively. After adjustment, hypocholesterolaemia remained independently associated with 30-day (adjusted hazard ratio [HR] = 1.50, 95% confidence interval [CI] 1.07 to 2.09; P < 0001) and 3-year (HR = 1.29 [1.12-1.47]; P <.001) mortality. Statin therapy on admission was independently associated with 30-day (HR = 0.61 [0.43-0.86]; P =.012) and 3-year (HR = 0.82 [0.72-0.94]; P =.017) mortality with no statin-by-cholesterol interaction with respect to 30-day (adjusted Pint = 0.669) or 3-year (adjusted Pint = 0.767) all-cause mortality suggesting that statins reduce the risk of mortality irrespective of cholesterol level. Conclusions: In patients with CAD, hypocholesterolaemia on admission was independently associated with increased risk of all-cause mortality at 30 days and 3 years after PCI.