The prevalence of symptomatic orthostatic hypotension in patients with Parkinson's disease and atypical parkinsonism.

Non-motor symptoms in Parkinson disease (PD) have been increasingly recognized as a major cause of declining health-related quality of life. We aimed to determine the prevalence of symptomatic orthostatic hypotension (OH) in patients with PD and atypical parkinsonism, and to evaluate the risk factors for OH in this population. We reviewed the records of 1318 patients diagnosed with PD or atypical parkinsonism at the Parkinson's Disease Center and Movement Disorders Clinic, Baylor College of Medicine. The frequency of symptomatic OH was 81% (21/26) in patients with multiple system atrophy (MSA), 18% (198/1125) of PD patients, and 19% (31/167) of patients with non-MSA atypical parkinsonism. Among PD patients, those with symptoms of OH were significantly older (p = 0.001), had more advanced Hoehn & Yahr stage (p = 0.007), a longer duration of PD symptoms (p = 0.031), and a greater range between their highest and lowest sitting systolic and diastolic BPs (p = 0.0001) over time. In the atypical parkinsonism group, excluding MSA, patients with symptoms of OH were taking more anti-hypertensive medications than those without symptoms of OH (p = 0.043). On the other hand, MSA patients with symptoms of OH were less likely to be taking anti-hypertensive medications than those without symptoms (p = 0.035). In conclusion, symptomatic OH is a common cause of disability in patients with PD, atypical parkinsonian disorders, and especially in patients with MSA.