Incidence, Clinical Correlates, and Prognostic Impact of Dementia in Heart Failure: A Population-Based Cohort Study

Background: Heart failure (HF) may increase the risk of dementia via shared risk factors. Objectives: The authors investigated the incidence, types, clinical correlates, and prognostic impact of dementia in a population-based cohort of patients with index HF. Methods: The previously territory-wide database was interrogated to identify eligible patients with HF (N = 202,121) from 1995 to 2018. Clinical correlates of incident dementia and their associations with all-cause mortality were assessed using multivariable Cox/competing risk regression models where appropriate. Results: Among a total cohort aged ≥18 years with HF (mean age 75.3 ± 13.0 years, 51.3% women, median follow-up 4.1 [IQR: 1.2-10.2] years), new-onset dementia occurred in 22,145 (11.0%), with age-standardized incidence rate of 1,297 (95% CI: 1,276-1,318) per 10,000 in women and 744 (723-765) per 10,000 in men. Types of dementia were Alzheimer's disease (26.8%), vascular dementia (18.1%), and unspecified dementia (55.1%). Independent predictors of dementia included: older age (≥75 years, subdistribution hazard ratio [SHR]: 2.22), female sex (SHR: 1.31), Parkinson's disease (SHR: 1.28), peripheral vascular disease (SHR: 1.46), stroke (SHR: 1.24), anemia (SHR: 1.11), and hypertension (SHR: 1.21). The population attributable risk was highest for age ≥75 years (17.4%) and female sex (10.2%). New-onset dementia was independently associated with increased risk of all-cause mortality (adjusted SHR: 4.51; P < 0.001). Conclusions: New-onset dementia affected more than 1 in 10 patients with index HF over the follow-up, and portended a worse prognosis in these patients. Older women were at highest risk and should be targeted for screening and preventive strategies.