Study data suggest that even in early disease, motor complications are common and accompanied by a greater burden of nonmotor symptoms than previously known.
Diego Santos-Garcia, MD
Data published in the European Journal of Neurology suggest that patients with Parkinson disease not only suffer from frequent motor complications, but these complications are associated with a greater nonmotor symptom burden during the first 5 years of the disease course than previously known.
Conducted by Diego Santos‐Garcia, MD, neurology specialist, University Hospital Complex of A Coruna, and colleagues, the study findings showed that higher Non-Motor Symptoms Scale (NMSS) scores were significantly related to Unified Parkinson’s Disease Rating Scale (UPDRS‐IV) scores when adjusted for a number of variables (β =0.27; 95% CI, 2.81—5.61; P <.0001). Additionally, when running a logistic regression model on dichotomous NMSS total score (mild or moderate, ≤40 vs. severe or very severe, >40), there were similar results, with an odds ratio (OR) of 1.31 (95% CI, 1.17—1.47; P <.0001).
“The present study suggests a relationship between motor complications and nonmotor symptoms in early Parkinson disease patients. Motor complications are frequent and are related to nonmotor symptom burden even in the first years after diagnosis,” Santos-Garcia and colleagues wrote. “They should be identified because are related to a worse quality of life and autonomy for activities of daily living for Parkinson patients.”
Overall, the study population consisted of 690 patients with Parkinson disease who were a mean of 62.6 (±8.9) years old. Of that group, 33.9% (n = 234) presented motor fluctuations and 18.1% (n = 125) presented dyskinesia. Those with motor fluctuations had higher overall NMSS scores (59.2 [±43.1]) compared to those without (38.3 [±33.1]; P <.0001), and similar differences were seen for those with dyskinesia (63.5 [±40.7]) compared to those without (41.4 [±36.3]; P <.0001).
In total, 5 patients presented no nonmotor symptoms (NMSS score, 0; 0.7%), 188 with mild burden (27.2%), 204 with moderate burden (29.6%), 159 with severe burden (23%), and 134 with very severe burden (19.4%).
Additionally, Santos-Garcia et al. observed that upward of 50% and 30% of patients with very severe nonmotor symptom burden presented with fluctuations and dyskinesia, respectively. In comparison to those with mild burden, those values were 20% and 10%, respectively. NMSS total score was higher in patients with more time spent in OFF state and more time with dyskinesia. Those who experienced early morning dystonia, as well as those with predictable, unpredictable, or sudden OFF episodes, also had higher scores.
In a subgroup of early Parkinson disease patients (n = 396; mean disease duration 2.7 [±1.5] years), motor fluctuations were frequent, occurring in 18.1% (n = 75) of patients, though dyskinesia was present in only 5.8% (n = 23). Overall, similar results were obtained. NMSS total score was significantly higher in those with motor fluctuations (59.3 [±44.6]) compared to those without (38.3 [±33.4]; P <.0001), and those with dyskinesia (65 [±35.8]) compared to those without (40.9 [±36.3]; P = .002).
“Previous studies have explored the frequency of nonmotor symptoms and motor complications in Parkinson disease and our results are aligned with them,” Santos-Garcia et al. detailed. “Although previous reports demonstrated that approximately 40% of Parkinson patients who were treated with levodopa for 4-6 years experienced motor complications, studies, examining more specifically wearing-off, have observed that this is a potentially early phenomenon, affecting already 42% of the patients with <2.5 years of disease when a screening tool was used (WOQ-19) and 21% according to neurologist assessment.”
This study detected a wearing-off prevalence of about 15% in the subgroup of early disease patients, the authors noted, adding that although nonmotor symptoms and their burden are greater in long-term patients, those who are drug-naïve experience them commonly, too.
“Over 45% of patients may have severe to very severe nonmotor symptom burden. In the present study, more than 35% of patients from early subgroup presented severe to very severe nonmotor symptom burden,” they wrote.
Santos-Garcia and colleagues did acknowledge a few limitations to the work, most notably that the sample was perhaps not fully representative of the overall population due to their exclusion of patients due to age, co-existing dementia and severe comorbidities, and no second-line therapies, among others. Although, they noted that this is the first work to explore, in detail, the relationship between nonmotor symptoms and motor complications in early disease patients.
Santos-Garcia D, de Deus Fonticoba T, Castro ES, et al. Non‐motor symptoms burden is strongly correlated to motor complications in Parkinson´s disease patients. Eur J Neurol. Published online March 17, 2020. Accessed March 27, 2020. doi: 10.1111/ene.14221