It is accepted that orthostatic hypotension is a clinical marker for the diagnosis of multiple system atrophy, but conflicting data indicate that it may also be present in Parkinson disease (PD).
To evaluate the prevalence of autonomic cardiovascular impairment and orthostatic hypotension in a large group of patients with de novo PD, followed up for at least 7 years, to clinically confirm the diagnosis of the disease.
During a 2-year recruiting period, 60 untreated patients diagnosed as having idiopathic PD underwent autonomic cardiovascular function evaluation using the Ewing test. Patients subsequently received dopaminergic therapy and their condition was followed up for at least 7 years.
Nine (15%) of 60 patients were excluded from the study because during the follow-up period a parkinsonian syndrome was diagnosed (5 had multiple system atrophy and 4 had progressive supranuclear palsy). Data from 51 patients with PD underwent final statistical analysis and the results were compared with those of 51 age-matched healthy control subjects who had taken the same battery of autonomic tests. A statistically significant difference was found in postural hypotension (P = .02) and deep breathing test results (P = .03) between patients and controls. Seven (14%) of 51 patients with PD and 3 (60%) of 5 patients with multiple system atrophy had a decrease of more than 20 mm Hg in systolic blood pressure on standing.
Data from this study indicate a high prevalence of sympathetic and parasympathetic failure in patients with de novo PD, and when using a decrease of at least 20 mm Hg in systolic blood pressure, manometric orthostatic hypotension was found in 7 (14%) of the 51 patients with de novo PD.