To determine if orthostatic hypotension (OH) impacts cognition in Lewy body dementia (LBD).

Twenty-one older adults (> 60 years old) with LBD (10 with and 11 without OH) were recruited from the URMC Movement Disorders and Memory Care Clinics. Participants underwent orthostatic blood pressure testing and neuropsychological assessment [the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS)]. Dementia and disease severity were obtained using standardized rating instruments. OH was defined by drop in systolic/diastolic blood pressure ≥20/10 mmHg. Correlational analyses were conducted to determine factors associated with cognitive function.  Analysis of variance was conducted to determine group differences in cognitive performance after controlling for those factors. 

The groups did not differ in age or disease duration, but the OH group had a higher level of education than the non-OH group (16.1 vs. 13.4 years, p=0.043). The RBANS Total and Visuospatial Index scores were negatively associated with the UPDRS Part 3 (r = -.46, p=.039 and r = -.47, p=.037, respectively). The RBANS Language Index score was negatively associated with the UPDRS Anxiety score (r= -.48, p =.03).  The OH group performed significantly worse on the RBANS Visuospatial Index and Total scores, though the latter did not reach statistical significant (59 vs 69, p = .034; 57 vs 63, p= .059, respectively).  Follow-up analysis revealed that the OH group performed significantly worse on the Figure Copy and Figure Recall subtests (6.1 vs 10.4, p = .009; 2.9 vs 6.3, p =.036, respectively).

Our findings suggest that co-morbid OH may contribute to impairment in visuospatial construction and visuospatial memory. OH may represent a modifiable contributor to cognitive impairment in LBD.