Evaluation of Systolic and Diastolic Hypotension in Dementia with Lewy Bodies and Alzheimer’s Disease

Abstract

Background: Orthostatic hypotension (OH) can be seen in as many as 30% to 50% of the elderly population as well as in dementia. OH is part of the autonomic dysfunction in dementia with Lewy bodies (DLB) and prevalent in the majority of these patients. It is also suggested to be a negative prognostic factor for survival in DLB. A detailed interpretation of the 10-minute orthostatic blood pressure measurement has shown prolonged orthostasis in DLB compared with other dementias. The type of OH (systolic and diastolic) has not been separately investigated in different dementias. Objectives: The aims of this study were to analyze the type of orthostatic hypotension, systolic and/or diastolic, in different dementia groups compared with normal controls. Patients and Methods: One-hundred fifty-six individuals, 52 with DLB, 50 with Alzheimer’s disease (AD), 54 AD with vascular components (ADvasc), and 62 normal controls, were included. As part of each patient’s routine clinical dementia investigation, systolic and diastolic blood pressure measurements were examined in the supine position, immediately after standing up, and after 1, 3, 5, and 10 minutes of standing. OH was defined as a blood pressure drop of 20 mmHg systolic or 10 mmHg diastolic, and the type of OH—­systolic, diastolic or both—was defined. Results: Orthostatic hypotension was severely underdiagnosed before the dementia investigation with only 2% to 4% in the dementia groups, while we found that 69% of DLB, 50% of ADvasc, 38% of AD, and 13% of normal controls had OH. A combination of systolic and diastolic OH was the most common type of OH both in the DLB (67%) and ADvasc (48%) groups, while systolic OH was the most common type in AD (63 %) as well as in normal controls (63%). Mini Mental State Examination scores differed significantly (P , 0.001) between the group with no OH (25.2 ± 4.8) and the group with combined systolic and diastolic OH (22.0 ± 4.8). Conclusion: Patients with DLB showed a greater proportion of combined systolic and diastolic hypotension. This might suggest a more complex OH than in patients with AD or elderly controls, possibly exacerbating the clinical picture in DLB. Further investigations of the relevance of these findings and the relation to clinical symptoms are needed.