Background/Aims: Parkinson’s disease (PD) is a chronic and progressive neurodegenerative disease, which affect 1% of the population. The disorders is characterized as a neurodegenerative disease, which affects the basal ganglia and is known by loss of dopamine-containing neurons in substantia nigra pars compacta. PD affects both motor and sensory, but the aim of this study was to investigate whether PD patients have an altered sensory and pain perception in response to non-painful and painful stimuli and further investigate whether the PD medication taken by the PD patients can have an effect on the responsiveness to the perception of touch and pain.
Methods: Twelve PD patients (9 male and 3 female) and twelve healthy controls (8 male and 4 female) were studied. Sensory perception was investigated in both forearms, lower back and both hands by four tests; brush test, pinprick test, cold pressure test (CPT) and pressure pain threshold (PPT) test. In all tests, the PD patients and healthy controls rated the pain intensity on VAS. Mini mental state examination (MMSE) was used to check the cognitive function in both PD patients and healthy controls and McGill Pain Questionnaire was used to locate the pain area in PD patients with pain. The PD medication was studied in relation to the effect on sensory disturbances.
Results: There were a significant difference in right (P=0.021) and left forearms (P=0.025) and lower back (P=0.002) between PD patients and healthy subjects in the brush test. PD patients had increased pain intensity in the pinprick test; mean was calculated of each pinprick stimulus (8mN, 16mN, 32mN, 64mN, 128mN, 256mN and 512mN) and there were a significant difference between each stimulus (P<0.001). There were no significant difference between PD patients and healthy controls in the right forearm and left forearm, but a significant difference in lower back (P<0.001) in the pinprick test. CPT showed at significant result in tolerance time (P=0.016). There were a significant difference between PD patients and healthy controls in PPT before (P=0.011) and after (P=0.050) the CPT, but there was no significant difference in non-dominant hand and lower back. There was no difference showed in sensory test in relation to PD medication.
Conclusion: We found that PD patients had altered perception of touch and pain. PD patients had increased pain intensity to non-painful and painful stimuli. The sensory disturbance was independent of PD medication.