Temporal trends in prevalence and prognostic implications of comorbidities among patients with acute decompensated heart failure: The ARIC study community surveillance

Background: Patients with heart failure (HF) have multiple coexisting comorbidities. The temporal trends in the burden of comorbidities and associated risk of mortality among patients with HF with preserved ejection fraction (HFpEF) and HF with reduced ejection fraction (HFrEF) are not well established. Methods: HF-related hospitalizations were sampled by stratified design from 4 US areas in 2005 to 2014 by the community surveillance component of the ARIC study (Atherosclerosis Risk in Communities). Acute decompensated HF was classified by standardized physician review and a previously validated algorithm. An ejection fraction <50% was considered HFrEF. A total of 15 comorbidities were abstracted from the medical record. Mortality outcomes were ascertained for up to 1-year postadmission by linking hospital records with death files. Results: A total of 5460 hospitalizations (24 937 weighted hospitalizations) classified as acute decompensated HF had available ejection fraction data (53% female, 68% white, 53% HFrEF, 47% HFpEF). The average number of comorbidities was higher for patients with HFpEF versus HFrEF, both for women (5.53 versus 4.94; P<0.0001) and men (5.20 versus 4.82; P<0.0001). There was a significant temporal increase in the overall burden of comorbidities, both for patients with HFpEF (women: 5.17 in 2005-2009 to 5.87 in 2010-2013; men: 4.94 in 2005-2009 and 5.45 in 2010-2013) and HFrEF (women: 4.78 in 2005-2009 to 5.14 in 2010-2013; men: 4.62 in 2005-2009 and 5.06 in 2010-2013; P-trend<0.0001 for all). Higher comorbidity burden was significantly associated with higher adjusted risk of 1-year mortality, with a stronger association noted for HFpEF (hazard ratio [HR] per 1 higher comorbidity, 1.19 [95% CI, 1.14-1.25] versus HFrEF (HR, 1.10 [95% CI, 1.05-1.14]; P for interaction by HF type=0.02). The associated mortality risk per 1 higher comorbidity also increased significantly over time for patients with HFpEF and HFrEF, as well (P for interaction with time=0.002 and 0.02, respectively) Conclusions: The burden of comorbidities among hospitalized patients with acute decompensated HFpEF and HFrEF has increased over time, as has its associated mortality risk. Higher burden of comorbidities is associated with higher risk of mortality, with a stronger association noted among patients with HFpEF versus HFrEF.