Impact of upright posture on cognitive function in orthostatic hypotension: A systematic review

Orthostatic hypotension is characterized by the reduced ability to compensate for a decrease in blood pressure upon standing and is prevalent among elderly populations as well as many pathophysiological conditions. Orthostatic hypotension is also associated with the development of mild cognitive impairment, cognitive decline, and dementia. While associations have been observed between the presence of orthostatic hypotension and impaired cognitive performance, few studies have assessed cognitive function in both supine and upright postures in individuals with orthostatic hypotension. We conducted a systematic review to examine the influence of upright posture on cognitive function in orthostatic hypotension. The review was registered with Prospero (CRD42025649093), and the following databases were searched from inception to 16 December 2024: Ovid Medline, Embase, Cochrane Central Register of Controlled Trials, APA PsychINFO, CINAHL, and Web of Science. Eight studies which met our inclusion criteria of cognitive function testing completed in both postures underwent data extraction. All pathophysiological conditions were considered, however, only studies that included subgroups with isolated or concurrent orthostatic hypotension, that also reported findings specific to that group, were included. Our findings suggest that cognitive function is worse in upright posture compared to supine posture in individuals with orthostatic hypotension across several cognitive domains (global function, attention and processing speed, executive function, language, memory and learning, visuospatial skills). Further research is required to elucidate relationships between posture and cognition and address several limitations such as the variety of head-up tilt angles, duration of supine and upright conditions, restricting ambulation between conditions, and use of appropriate statistical analysis.