Predictors of postprandial hypotension in elderly patients with de novo Parkinson's disease.

Postprandial hypotension is one of the most important autonomic disorders in Parkinson's disease. However, its predictors remain unclear. We investigated which variable(s) predict the presence of postprandial hypotension in elderly patients with Parkinson's disease. The subjects were 64 patients with de novo Parkinson's disease who were 70 years or older. Postprandial hypotension was evaluated on a 75-g oral glucose tolerance test. Olfactory function, constipation, cardiac sympathetic or parasympathetic denervation, orthostatic intolerance on head-up tilt table testing, and other baseline characteristics were evaluated. The results showed the presence of postprandial hypotension was associated with severe dysosmia, constipation, orthostatic hypotension (a decrease in systolic blood pressure ≥30 mmHg) and preprandial hypertension at rest. On multiple logistic regression analyses adjusted for age, sex, symptom duration, disease severity, and motor subtype, the odds ratio was 4.02 for severe dysosmia (p = 0.027), 9.99 for constipation (p = 0.006), 6.42 for orthostatic hypotension with alternative definition (p = 0.004) and 7.90 for preprandial hypertension at rest (p = 0.001). Each multiple logistic regression analysis revealed that female sex was also a risk factor for postprandial hypotension. The variables with the highest sensitivity and specificity for postprandial hypotension were constipation (89.6 %) and preprandial hypertension at rest or orthostatic hypotension with alternative definition (both 77.1 %), respectively. Our results suggest that these variables predict the presence of postprandial hypotension in elderly patients with Parkinson's disease, suggesting that postprandial hypotension shares etiologic factors with these potential predictors.