Breathing and locomotion in patients with Parkinson's disease

The phase relationship between respiration and locomotion was examined in t en patients with Parkinson's disease (PD, mean age 65, range 51-79 years) a nd in six healthy subjects (mean age 63, range 58-68 years). Locomotion was measured by means of pressure sensors attached below the subjects' feet. R espiration was measured using respiratory inductive plethysmography. The da ta were recorded with a battery-driven portable device. We determined the c oordination degree as the portion of steps which occurred within 12/50 bins of the respiratory cycle. The mean degree of coordination of PD patients w as 45.0%+/- 11.9%, for the healthy subjects 85.1%+/- 10.8% (P <0.001). Thre e healthy subjects showed a 2:1 ratio between step and breathing rate, thre e a 3:2 ratio. Two PD patients showed a coordination of 4: 1 and 3: 1, resp ectively, with a larger scatter than in controls. In the other eight patien ts steps were almost equally distributed over the entire respiratory cycle. We conclude that in patients with PD the coordination between locomotion a nd breathing is reduced.