Association of cognitive impairment and peripheral artery disease (PAD): A systematic review

This systematic review aimed to describe the association between peripheral artery disease (PAD) and cognitive impairment or dementia. We included studies reporting on the association between PAD (defined by ankle-brachial index ⩽ 0.9) and cognitive function in adult populations. MEDLINE, Embase, CINAHL, PsycINFO, and CENTRAL were systematically searched from inception to January 2025. Study quality was assessed using the Risk of Bias In Nonrandomized Studies of Exposure effects (ROBINS-E) tool. A narrative synthesis was undertaken structured by cognitive outcome and study design. Thirty-eight studies were included in the review (58,586 participants). The results provide evidence that PAD is associated with cognitive impairment. Seventeen (81%) cross-sectional studies and four (67%) longitudinal studies reported associations of PAD with poorer cognitive performance or increased risk of cognitive impairment. Impaired memory and processing speed were most frequently associated with PAD. PAD was also associated with increased dementia risk in cross-sectional (odds ratios = 1.50-2.41) and longitudinal studies (hazard ratios = 1.03-2.40), although proportionally fewer longitudinal studies reported significant association of PAD with dementia. Results suggest increased prevalence of cognitive impairment, independent of cardiovascular risk factors and cerebrovascular disease. Awareness of the prevalence of cognitive impairment and its potential impact on treatment adherence and engagement in a healthy lifestyle is important for clinicians treating patients with PAD. Screening for cognitive impairment in those with PAD may aid early diagnosis and management of cognitive impairment in this high-risk population. Further research is required to determine whether screening for and optimal management of PAD has cognitive benefits. (PROSPERO Registration No.: CRD42023399608).