[Postprandial hypotension in Parkinson's disease--the incidence and risk factor]

To clarify the incidence and risk factor of postprandial hypotension (PPH) in Parkinson's disease, a 75g oral glucose tolerance test (OGTT) was carried out in 23 patients (Hoehn-Yahr score II in 2, III in 18 and IV in 3) without postprandial symptoms. We defined the patients whose systolic blood pressure fell more than 20 mmHg during the 75g OGTT as group I and less than 20 mmHg as group II. In 14 patients with Parkinson's disease (61%), the systolic blood pressure fell more than 20 mmHg without symptoms. There were no significant differences in in age, disease duration, clinical stage or antiparkinsonian drug between groups I and II. However, the baseline systolic and diastolic blood pressures were significantly higher in group I than in group II. In group I patients, the maximum decrease in systolic blood pressure was seen after more than 60 minutes and serum insulin response was higher than in group II patients from 60 to 120 min. Systolic blood pressure declined accompanied by the rise of insulin. These results suggest that PPH occurs at high incidence in patients with moderately severe Parkinson's disease, and that high baseline blood pressure and abnormally high insulin response to glucose load may play a role, while medications for Parkinson's disease may not.