Comorbidities are a major concern in heart failure, leading to adverse outcomes, increased health care utilization, and excess mortality. Nevertheless, the epidemiology of comorbid conditions and differences in their occurrence by type of heart failure and sex are not well documented.

The prevalence of 16 chronic conditions defined by the US Department of Health and Human Services was obtained among 1382 patients from Olmsted County, Minn. diagnosed with first-ever heart failure between 2000 and 2010. Heat maps displayed the pairwise prevalences of the comorbidities and the observed-to-expected ratios for occurrence of morbidity pairs by type of heart failure (preserved or reduced ejection fraction) and sex.

Most heart failure patients had 2 or more additional chronic conditions (86%); the most prevalent were hypertension, hyperlipidemia, and arrhythmias. The co-occurrence of other cardiovascular diseases was common, with higher prevalences of co-occurring cardiovascular diseases in men compared with women. Patients with preserved ejection fraction had one additional condition compared with those with reduced ejection fraction (mean 4.5 vs 3.7). The patterns of co-occurring conditions were similar between preserved and reduced ejection fraction; however, differences in the ratios of observed-to-expected co-occurrence were apparent by type of heart failure and sex. In addition, some psychological and neurological conditions co-occurred more frequently than expected.

Multimorbidity is common in heart failure, and differences in co-occurrence of conditions exist by type of heart failure and sex, highlighting the need for a better understanding of the clinical consequences of multiple chronic conditions in heart failure patients.