Association of Dyslipidemia and Concomitant Risk Factors with In-Hospital Mortality in Acute Coronary Syndrome in Switzerland

Abstract

Background: Although dyslipidemia is one of the main risk factors for cardiovascular diseases, very few randomized trials have provided data on the association of dyslipidemia and in-hospital mortality in patients with acute coronary syndrome (ACS). Objective: The study assessed the association of dyslipidemia and concomitant risk factors, and early lipid-lowering therapy (LLD) on in-hospital mortality in patients admitted for ACS. Methods: Using AMIS Plus registry data, 13,482 patients admitted between January 1997 and October 2003 were analyzed, and logistic regression was used for predicting in-hospital mortality. Results: Baseline characteristics of patients with dyslipidemia (n = 6,079) significantly differed from those without, and in-hospital mortality was lower (5.5 vs. 9.4%; p < 0.001). Subgroup analyses of 9,383 patients with one or more of four preexisting main risk factors (hypertension, diabetes, coronary heart disease, CHD, or dyslipidemia) showed that whenever dyslipidemia was combined with another risk factor, the mortality rate clearly decreased. Patients with dyslipidemia were, in all subgroups, significantly younger (p < 0.001) and predominantly male, and they had more frequently primary percutaneous coronary intervention (PCI). However, this was only significant in patients with hypertension or hypertension and CHD. Independent in-hospital mortality predictors were age (odds ratio, OR: 1.08 per year, 95% confidence interval, CI, 1.07–1.09), diabetes (OR: 1.96, 95% CI: 1.56–2.46, p < 0.0001) and primary PCI (OR: 0.62, 95% CI: 0.44–0.86, p < 0.0001). In patients who received LLD, mortality was significantly lower regardless of the total cholesterol level measured within 24 h after symptom onset. Conclusion: Patients with dyslipidemia admitted for ACS had significantly lower in-hospital mortality than patients without dyslipidemia, mainly but not only due to the younger age of these patients. Early administration of LLD was associated with lower in-hospital mortality.