The prevalence and impact of comorbidities on outcomes in heart failure - a 15-Year Hungarian Nationwide Epidemiological Study (HF-EPI-HUN)

Background Comprehensive epidemiological data on the prevalence of heart failure in the general population remain scarce and often inconsistent. It is well established that comorbidities are highly prevalent in heart failure and exert a significant influence on clinical outcomes. This uniqe study aims to assess changes in the epidemiology of heart failure over the past decade in the entire population of Hungary, comprising 9.7 million people. Methods This retrospective, observational real-world evidence study examines the epidemiology and outcomes of heart failure patients in the Hungarian population using aggregated data from the National Health Insurance Fund (NHIF) database. The study period extends from January 1, 2009, to December 31, 2023. Patients with ICD codes I11, I13, I23, I42, I43, I50, or J81, recorded in either inpatient or outpatient care as a primary or secondary diagnosis, are included in the analysis. A two-year screening period from January 1, 2009, to December 31, 2010, was implemented, during which patients diagnosed with heart failure were excluded from the analyses. Key statistical metrics were analyzed, along with the comorbid status of patients diagnosed with heart failure. The comorbidities were defined based on a set of ICD codes, including diabetes (DM), hypertension (HT), ischemic heart disease (IHD), chronic kidney disease (CKD), stroke, obesity, chronic obstructive pulmonary disease (COPD), atrial fibrillation (AF), pulmonary arterial hypertension (PAH), peripheral artery disease (PAD), dementia, and depression. Results A total of 671,368 patients were enrolled in the study. The findings indicate that 63% of patients had three or more comorbid conditions. The ten most prevalent comorbidity combinations exhibited frequencies ranging from 60,613 for the most common combination to 13,855 for the tenth-ranked combination. The three most frequently observed comorbidity patterns were: 1. HT and IHD, 2. HT alone, 3. HT, IHD, and AF. The most prevalent unique comorbidity (age and sex standardised HF patient population) was HT (81%). Other significant comorbidities included IHD (66%), AF (41%), and DM (35%). CKD (22%) and COPD (20%) were also notably frequent. Age and gender had a significant impact on the prevalence of comorbidities. AF, CKD and, consequently, dementia were observed at higher rates in the elderly population, whereas DM, COPD, and obesity also significantly affected middle-aged patients. A female predominance was observed in CKD, obesity, PAH and dementia, whereas men were more prevalent in the IHD, AF, COPD, PAD and DM groups, while the distribution was balanced in HT. Conclusions Patients with heart failure often have one or more comorbidities, which significantly influence both prognosis and treatment. Understanding comorbidities, their combinations, and temporal trends at the population level provides crucial information for developing tailored treatment strategies for patients with heart failure.