Maya Asami Takagi, Adil Sarvar Mohammed, Uzma Yasmeen, Hunter Tianjiao Li, NG Patel, Mashood Farooqi, Simran Bhimani, Iramunisa Begum, Ihsan Nazar Mustafa Al-Sabbagh, Rupak Desai, Saad Ahmad Chaudhry, Sandesh Dev
Background Cognitive impairment (CI) is increasingly recognised as a common comorbidity among older adults with heart failure (HF) and is associated with reduced self-care, poor medication adherence, and worse clinical outcomes. Reported prevalence varies widely across studies due to differences in populations, cognitive assessment tools, and geographic regions. This systematic review and meta-analysis aimed to estimate the global prevalence of CI among older adults with HF and examine sources of variability across studies. Methods This systematic review and meta-analysis was conducted in accordance with PRISMA guidelines. PubMed and Scopus were searched from database inception to October 2024, with Google Scholar used as a supplementary source. Observational studies including adults aged ≥65 years with clinically diagnosed HF and validated cognitive assessments were included. Pooled prevalence estimates were calculated using a random-effects model with double arcsine (Freeman–Tukey) transformation. Heterogeneity was assessed using the I 2 statistic. Prespecified subgroup analyses were performed by age, geographic region, and study design. Sensitivity analyses were conducted using a leave-one-out approach. Results Twenty-five studies comprising 12,112 older adults with HF (mean age 80.0±4.9 years; 52.6% female) were included. Overall, 3,669 patients had CI, yielding a pooled prevalence of 43.5% (95%-confidence interval: 35.2%–51.9%) with substantial heterogeneity (I 2 =98.6%). CI prevalence was highest in the United States (50.9%), followed by Asia (46.5%) and Europe (35.0%). Patients aged ≥80 years demonstrated higher prevalence (48.6%) compared with those aged 70–79 years (38.9%). Prospective studies reported higher prevalence than retrospective designs. Sensitivity analyses confirmed the robustness of the findings. Conclusions Approximately 44% of older adults with HF have CI, representing a substantial global burden. These findings support routine cognitive screening in older HF populations to guide clinical decision-making and improve outcomes. Future studies should evaluate longitudinal cognitive trajectories and interventions aimed at improving both cognitive and cardiovascular outcomes.