Abstract
Background: The features of sleep-associated acute heart failure (AHF) patients admitted at midnight or early morning (M/E) are unclear. Methods and Results: Of 1,268 AHF patients screened, 932 were analyzed, and divided into 2 groups by admission time (M/E group, 23:00-06:59, n=399; daytime group, 07:00-22:59, n=533). Those in the M/E group were further divided by the presence of a prodrome: with (n=176; prodrome group) or without (n=223; sudden onset group). The median time from symptom onset to hospitalization was significantly shorter in the M/E group (98 min; range, 65-170 min) than in the daytime group (123 min; range, 68-246 min). The 365-day HF event rate in the M/E group was significantly lower than that of the daytime group. On multivariate logistic regression modeling the M/E group was independently associated with a better outcome than the daytime group (OR, 0.673; 95% CI: 0.500-0.905). In the M/E group, the 365-day HF event rate was significantly lower in the prodrome group than in the sudden onset group. On multivariate logistic regression modeling, inclusion in the prodrome group was independently associated with a better outcome (OR, 0.544; 95% CI: 0.338-0.877). Conclusions: AHF patients admitted during sleeping hours were not sicker than those admitted during the daytime. The absence of a prodrome, however, might be associated with future repeated HF events.