Presentations and outcomes of patients with acute decompensated heart failure admitted in the winter season

Abstract

Background: Seasonal variations in cardiovascular disease is well recognized. However, little is known about the presentations and outcomes of Japanese heart failure (HF) patients in the winter season.

Methods and results: We used a single hospital-based cohort from the Shinken Database 2004-2012, comprising all new patients (n=19,994) who visited the Cardiovascular Institute Hospital. A total of 375 patients who were admitted owing to acute decompensated HF were included in the analysis. Of these patients, 136 (36%) were admitted in winter. Winter was defined as the period between December and February. The HF patients admitted in winter were older, and had a higher prevalence of hypertension and diabetes mellitus than the patients admitted in other seasons. Patients with conditions categorized as clinical scenario 1 tended to be admitted more commonly in winter. HF with preserved left ventricular ejection fraction (LVEF) was more common in HF patients admitted in winter than in those admitted in other seasons. Beta-blocker use at hospital discharge was more common in the patients admitted in other seasons. Kaplan-Meier curves and log-rank test results indicated that the incidences of all-cause death, cardiovascular death, and HF admission were comparable between the patients admitted in winter and those admitted in other seasons.

Conclusions: HF admission was frequently observed in the winter season and HF patients admitted in the winter season were older, and had higher prevalence of hypertension and diabetes mellitus, and preserved LVEF suggesting that we might need to pay more attention for elderly patients with hypertension, diabetes mellitus, and HF with preserved LVEF to decrease HF admissions in the winter season.

Keywords: Heart failure; Japanese; Winter.