What Factors Influence Motor Complications in Parkinson Disease?: A 10-Year Prospective Study

The causes and mechanism behind motor complications in Parkinson disease (PD) are still a subject of debate. Several factors including age at onset, evolution in years, and initial medication can influence the onset and severity of motor complications in PD. We studied patients with recent diagnosis of PD who were followed up prospectively for 10 years. Analysis included the progression of these patients, as measured by the Unified Parkinson Disease Rating Scale scores and the presence of motor complications (motors fluctuations, dyskinesias, and gait freezing) over time. The patient group was studied as a whole and by subgroups classified according to age at onset, initial treatment, and sex. By the end of the first decade, most patients exhibited dyskinesias (91%), motor fluctuations (62%), and freezing of gait (68%). An association was found between several patients' characteristics and presence of motor complications by 5 years, though not after 10 years of follow up. The apparition of motor fluctuations was mainly related to initial treatment (odds ratio [OR], 3.87). The development of dyskinesias was linked to initial treatment (OR, 8.31), age at onset (OR, 0.90), and sex (OR, 12.87).