Prevalence of non-motor fluctuations in Parkinson’s disease in an outpatient tertiary referral center

Abstract

Introduction: motor fluctuations in Parkinson’s disease (PD) have been extensively studied, but much less is known about the behavior of non-motor symptoms. Objective: the objective of the present study is to characterize the non-motor fluctuations in patients with Parkinson’s disease attending an outpatient tertiary referral center, and correlating them with the main clinical features. Methods: patients with a diagnosis of Parkinson’s disease were included. The presence of non-motor symptoms was determined with the MDS-UPDRS Part 1A, and the severity and frequency of these symptoms were assessed with the Non-Motor Symptom Scale (NMSS). The Non-Motor Fluctuations Questionnaire (NMFQ) of the Spanish Society of Neurology was applied by independent evaluators, blinded to the motor assessment, to determine the fluctuating pattern of these features. Independent evaluators applied the Parkinson’s Disease Questionnaire Short Form (PDQ-8) to assess patients’ quality of life. Results: a total of 50 patients were included. Mean MDS-UPDRS IA score was 3.58 ± 3.28, and mean NMSS score was 58.29 ± 54.73. The most severe non-motor symptom was pain, followed by anxiety and depression. Twenty-six patients (52%) had at least one non-motor symptom with a fluctuating pattern. The most common fluctuating symptom was hallucinations (66.7%), followed by pain and paresthesias (44.4% each). Although there was a tendency for non-motor symptoms to present more frequently during off periods, no statistically significant results were found. Conclusion: non-motor fluctuations are frequent. Our findings suggest non-motor fluctuations are independent of motor fluctuations and pharmacological treatment.