Effect of medication withdrawal on pain in Parkinson's disease patients - an observational study based on a sample of patients without antiparkinsonian medications

ABSTRACT

SUMMARY OBJECTIVES: To assess the effect of withdrawal of the antiparkinsonian drug regimen administration on patients with PD and its relation to pain. METHODS: The sample included 22 men and 12 women who were candidates for neurosurgery to control motor signs and symptoms treated with L-dopa as a drug, alone or in combination with others (Cholinergic Antagonists; Dopamine Agents). All of them were examined at two different moments, with and without medication, and analyzed for painful symptoms. The Hoehn and Yahr scale was used for functional staging of the disease. Pain intensity was assessed by using the numerical verbal scale. RESULTS: The mean pain intensity among those on medication {2.17±0.39 (SE)} was significantly lower than in the abstinence group {4.2±0.59 (SE), p=0.006, Wilcoxon}, which corresponded to the increase in the total functional staging score from 93 to 111, respectively. CONCLUSION: The interruption of the administration of specific medications in patients with Parkinson's disease caused, or increased the intensity of, painful discomfort correlated with the intensity of functional impairment. This effect was also observed in women, but it was statistically relevant only for men. The results suggest that pain may be a "red flag" that points to the need for a therapeutic drug review when its presence or worsening is detected.