Prevalence and Prognostic Significance of Malnutrition in Patients With Acute Coronary Syndrome

Abstract

Background: Malnutrition is associated with poor prognosis in a wide range of illnesses. However, its prognostic impact in patients with acute coronary syndrome (ACS) is not well known.

Objectives: This study sought to report the prevalence, clinical associations, and prognostic consequences of malnutrition in patients with ACS.

Methods: In this study, the Controlling Nutritional Status (CONUT) score, the Nutritional Risk Index (NRI), and the Prognostic Nutritional Index (PNI) was applied to 5,062 consecutive patients with ACS. The relationships between malnutrition risk and all-cause mortality and major cardiovascular events (MACEs) (cardiovascular mortality, reinfarction, or ischemic stroke) were examined.

Results: According to the CONUT score, NRI, and PNI, 11.2%, 39.5%, and 8.9% patients were moderately or severely malnourished, respectively; 71.8% were at least mildly malnourished by at least 1 score. Although worse scores were most strongly related to lower body mass index, between 8.4% and 36.7% of patients with a body mass index of ≥25 kg/m² were moderately or severely malnourished, depending on the nutritional index used. During a median follow-up of 3.6 years (interquartile range: 1.3 to 5.3 years), 830 (16.4%) patients died, and 1,048 (20.7%) had MACEs. Compared with good nutritional status, malnutrition was associated with significantly increased risk for all-cause death (adjusted hazard ratio for moderate and severe degrees of malnutrition, respectively: 2.02 [95% confidence interval (CI): 1.65 to 2.49] and 3.65 [95% CI: 2.41 to 5.51] for the CONUT score, 1.40 [95% CI: 1.17 to 1.68] and 2.87 [95% CI: 2.17 to 3.79] for the NRI, and 1.71 [95% CI: 1.37 to 2.15] and 1.95 [95% CI: 1.55 to 2.45] for the PNI score; p values <0.001 for all nutritional indexes). Similar results were found for the CONUT score and PNI regarding MACEs. All risk scores improve the predictive ability of the GRACE (Global Registry of Acute Coronary Events) risk score for both all-cause mortality and MACEs.

Conclusions: Malnutrition is common among patients with ACS and is strongly associated with increased mortality and cardiovascular events. Clinical trials are needed to prospectively evaluate the efficacy of nutritional interventions on outcomes in patients with ACS.

Keywords: acute coronary syndrome; major cardiovascular events; malnutrition; mortality.