Association of Orthostatic Hypotension With Cerebral Atrophy in Patients With Lewy Body Disorders.

Objective: To evaluate whether orthostatic hypotension (OH) or supine hypertension (SH) is associated with brain atrophy and white matter hyperintensities (WMH), we analyzed clinical and radiological data from a large multicenter consortium of patients with Parkinson’s disease (PD) and dementia with Lewy bodies (DLB). Methods: Supine and orthostatic blood pressure and structural magnetic resonance imaging data were extracted from PD and DLB patients evaluated at eight tertiary-referral centers in the USA, Canada, Italy, and Japan. OH was defined as a systolic/diastolic BP fall ≥20/10 mm/Hg within 3 minutes of standing from the supine position (severe, ≥30/15 mm/Hg) and SH as a BP ≥140/90 mmHg with normal sitting blood pressure. Diagnosis-, age-, sex-, and disease duration-adjusted differences in global and regional cerebral atrophy, as well as WMH were appraised using validated semi-quantitative rating scales. Results: A total of 384 patients (310 with PD, 74 with DLB) met eligibility criteria, of whom 44.3% (n= 170) had OH, including 24.7% (n= 42) with severe OH, and 41.7% (n= 71) with SH. OH was associated with global brain atrophy (p=0.004) and regional atrophy involving the anterior-temporal (p= 0.001) and medio-temporal (p=0.001) regions, greater in severe vs. non-severe OH (p=0.001). The WMH burden was similar in those with and without OH (p=0.49). SH was not associated with brain atrophy (p=0.59) or WMH (p=0.72). Conclusions: OH, but not SH, was associated with cerebral atrophy in Lewy body disorders, with prominent temporal region involvement. Neither OH nor SH were associated with WMH.