Heart failure and dementia: a comparative analysis with different types of cancer

Aims The prognosis and quality of life of patients with heart failure (HF) is determined by comorbidities, with dementia/cognitive decline believed to have a significant impact in this regard. This study compares the incidence of dementia in patients with HF with that in patients with common cancers in a large collective of outpatients. Methods and results This retrospective cohort study assessed the incidence of dementia/cognitive decline [International Classification of Diseases, 10th revision (ICD-10): I50] in a cohort of patients ≥65 years diagnosed with HF (ICD-10: I50), breast cancer (ICD-10: C50), prostate cancer (ICD-10: C61), or digestive organ cancer (ICD-10: C15-C26) in 1274 German general practices between January 2000 and December 2018. Multivariable Cox regression models were used to study the association between HF and dementia compared to each of three cancer cohorts. We included 72 259 patients with HF, 10 310 patients with breast cancer, 12 477 patients with prostate cancer, and 12 136 patients with digestive organ cancer. A total of 27.8% of patients with HF were diagnosed with dementia during the 10-year observation period compared to 16.2% of patients with breast cancer, 18.6% of patients with digestive organ cancer, and 16.1% of patients with prostate cancer. Patients with HF were significantly more likely to develop dementia within 10 years after diagnosis than patients with breast cancer [hazard ratio (HR): 1.36 (95% confidence interval 1.28–1.45, P < 0.001], prostate cancer [HR 1.38 (1.130–1.47), P < 0.001], or gastrointestinal tumours [HR 1.31 (1.24–1.39), P < 0.001]. Conclusions Our study demonstrates the significance of dementia in patients with HF, in whom the condition is much more prevalent than in patients with cancer.