Characteristics and outcomes of patients with acute decompensated heart failure developing after hospital admission.

There are limited data on acute decompensated heart failure (ADHF) that develops after hospital admission. This study sought to compare patient characteristics, co-morbidities, mortality, and length of stay by timing of ADHF onset. The surveillance component of the Atherosclerosis Risk in Communities study (2005 to 2011) sampled, abstracted, and adjudicated hospitalizations with select International Classification of Disease, Ninth Revision, Clinical Modification discharge codes from 4 United States communities among those aged ≥55 years. We included 5,602 validated ADHF hospitalizations further classified as preadmission or postadmission onset. Vital status was assessed up to 1 year since admission. We estimated multivariate-adjusted associations of in-hospital mortality and 28- and 365-day case fatalities with timing of ADHF onset (postadmission vs preadmission). All analyses were weighted to account for the stratified sampling design. Of 25,862 weighted ADHF hospitalizations, 7% had postadmission onset of ADHF. Patients with postadmission ADHF were more likely to be older, white, and women. The most common primary discharge diagnosis codes for those with postadmission ADHF included diseases of the circulatory or digestive systems or infectious diseases. Short-term mortality among postadmission ADHF was almost 3 times that of preadmission ADHF (in-hospital mortality: odds ratio 2.7, 95% confidence interval 1.9 to 3.9; 28-day case fatality: odds ratio 2.6, 95% confidence interval 1.8 to 3.7). The average hospital stay was almost twice as long among postadmission as preadmission ADHF (9.6 vs 5.0 days). In conclusion, postadmission onset of ADHF is characterized by differences in co-morbidities and worse short-term prognosis, and opportunities for reducing postadmission ADHF occurrence and associated risks need to be studied.