Standing worsens cognitive functions in patients with neurogenic orthostatic hypotension.

In previous studies, addressing the association between orthostatic hypotension and cognitive decline, patients underwent neuropsychological evaluation in sitting position, and blood pressure values and cognition were not measured concurrently. Furthermore, no studies assessed the acute effects of orthostatic hypotension on cognitive performances. The aim of our study was to evaluate the effect of a documented fall in systolic blood pressure (SBP) of at least 20 mmHg on a battery of cognitive tests in patients with neurogenic orthostatic hypotension. Ten consecutive patients with neurogenic orthostatic hypotension, normal brain imaging, and a normal Mini Mental State Examination in supine position were enrolled in the study. Patients underwent a detailed neuropsychological assessment (Brief Mental Deterioration battery and computerized tests) over two test sessions: the first while tilted to an angle able to cause a fall of at least 20 mmHg in SBP; the second while supine, after 30 min of rest. Parallel forms of the tests were presented on each testing session. Patients scored significantly worse in the visual search test, analogies test, immediate visual memory, and the measure of global cognitive functioning of Brief Mental Deterioration battery during the orthostatic challenge compared to the supine position. Orthostatic hypotension was associated with a significant worsening of cognitive performances, affecting both global cognitive functioning and specific tasks, mainly exploring executive functions. The assessment of cognitive function in patients with neurogenic orthostatic hypotension should be performed considering the body's position of the subject.