Blood pressure adaptation and hormonal regulation after orthostasis in patients with Parkinson's disease

Objective: To determine whether abnormal orthostatic regulation commonly occurs in patients with Parkinson's disease (PD) and is caused by an abnormal catecholamine release (especially of noradrenaline). Patients and methods: Blood pressure and catecholamine concentration were measured after 10-min recumbency and 1, 3, 5, 7 and 9 min after standing up in 46 patients with PD (15 women, 31 men: mean age 64.3 +/- 11.7 years). Results were compared with those in a group of 27 healthy controls (eight women, 19 men; mean age 60.7 +/- 10.8 years). Results: Among PD patients there were marked hypotonic circulatory reactions, associated with decreased catecholamine concentration and heart rate adaptation; an abnormal orthostatic regulation occurred in 30 patients. In 22 patients noradrenaline concentration changed by less than 200 pg/ml in the 9(th) min after standing up, while a decreased hormonal release was noted in only four of the controls, all of whom had normal orthostatic regulation. In PD patients the lowest adrenaline rise was always associated with an extremely high fall in blood pressure. Changes in mean blood pressure correlated positively with the rise in noradrenaline. There was no demonstrable correlation between medication for PD, age of patient and the duration or severity of the disease. Conclusion: Abnormal orthostatic regulation occurs more frequently in PD than in healthy persons and is associated with changes in noradrenaline release. This suggests multisystem degeneration as a cause of PD.