Orthostatic hypotension in Parkinson's disease: association with cognitive decline?

BACKGROUND: Orthostatic hypotension is common in Lewy body disorders and may be related to disease progression and the spread of Lewy body pathology. We therefore hypothesize that PD patients with orthostatic hypotension (OH) have a different cognitive profile compared to PD patients without OH. METHODS: This cross-sectional study included 175 PD patients. Blood pressure (BP) was measured with a validated digital blood pressure monitor and patients with a systolic BP drop of > or =20 mmHg or a systolic pressure of <90 mm Hg after standing were considered to have OH. Cognition was assessed using MMSE extended by a selection of computerized cognitive tests focusing on reaction time, sustained attention, working memory and episodic verbal and visual memory. RESULTS: Eighty-seven (49.7%) of the PD patients had OH. These patients were significantly more impaired in sustained attention and visual episodic memory compared to PD patients without OH. CONCLUSION: We conclude that there are differences in the neuropsychological performance of patients with PD and OH, supporting the hypothesis that OH might be a marker for disease progression and cognitive decline in PD.