Ambulatory blood pressure in patients with Parkinson's disease without and with orthostatic hypotension.

Non-invasive ambulatory recordings of blood pressure and heart rate were performed using a Spacelabs device during day and night periods in patients with Parkinson's disease with (n = 19) or without orthostatic hypotension (n = 19). In patients with orthostatic hypotension, the average systolic and diastolic blood pressure during the night (137 +/- 5/80 +/- 3 mmHg) was higher (p less than 0.05) than during the day period (121 +/- 3/76 +/- 2 mmHg). In patients without orthostatic hypotension, a decrease in blood pressure was recorded during the nocturnal period. In patients with orthostatic hypotension, the blood pressure variability was higher (p less than 0.05) during the day (systolic: 14.6 +/- 1.3%; diastolic: 16.5 +/- 1.0%) than during the night (systolic: 9.1 +/- 0.8%; diastolic: 10.8 +/- 1.1%). The blood pressure load (percentage of values above 140/90 mmHg) during the night was significantly higher than during the day for both systolic (41.2 +/- 8.1 vs. 19.6 +/- 4.7%) and diastolic blood pressure (24.9 +/- 6.9 vs. 16.3 +/- 4.9%). There was a decrease in heart rate in both groups during the night. A fall of 25 mmHg or more in systolic blood pressure after meals occurred in ten patients with orthostatic hypotension and in one patient without orthostatic hypotension. These results indicate that orthostatic hypotension in Parkinson's disease is associated with specific modifications of ambulatory blood pressure including loss of circadian rhythm of blood pressure, increased diurnal blood pressure variability and post-prandial hypotension.