Gastric emptying, postprandial blood pressure, glycaemia and splanchnic flow in Parkinson's disease

AIM: To determine gastric emptying, blood pressure, mesenteric artery blood flow, and blood glucose responses to oral glucose in Parkinson's disease. METHODS: Twenty-one subjects(13 M, 8 F; age 64.2 ± 1.6 years) with mild to moderate Parkinson's disease(Hoehn and Yahr score 1.4 ± 0.1, duration of known disease 6.3 ± 0.9 years) consumed a 75 g glucose drink, labelled with 20 MBq 99mTc-calcium phytate. Gastric emptying was quantified with scintigraphy, blood pressure and heart rate with an automated device, superior mesenteric artery blood flow by Doppler ultrasonography and blood glucose byglucometer for 180 min. Autonomic nerve function was evaluated with cardiovascular reflex tests and upper gastrointestinal symptoms by questionnaire. RESULTS: The mean gastric half-emptying time was 106 ± 9.1 min, gastric emptying was abnormally delayed in 3 subjects(14%). Systolic and diastolic blood pressure fell(P < 0.001) and mesenteric blood flow and blood glucose(P < 0.001 for both) increased, following the drink. Three subjects(14%) had definite autonomic neuropathy and 8(38%) had postprandial hypotension. There were no significant relationships between changes in blood pressure, heart rate or mesenteric artery blood flow with gastric emptying. Gastric emptying was related to the score for autonomic nerve function(R = 0.55, P < 0.01). There was an inverse relationship between the blood glucose at t = 30 min(R =-0.52, P < 0.05), while the blood glucose at t = 180 min was related directly(R = 0.49, P < 0.05), with gastric emptying. CONCLUSION: In mild to moderate Parkinson's disease, gastric emptying is related to autonomic dysfunction and a determinant of the glycaemic response to oral glucose.