Parkinson’s patients with non-motor symptoms during “wearing-off” periods — when symptoms return as their medication wears off — have a significantly worse quality of life compared to patients who only experience the return of motor symptoms, a new study shows.
The study, “Motor and non-motor wearing-off and its impact in the quality of life of patients with Parkinson’s disease,” was published in the journal Arquivos de Neuro-Psiquiatria.
Motor fluctuations refer to the alterations between periods of being “on,” during which a Parkinson’s patient experiences a positive response to medication (generally levodopa), and being “off,” during which the medication wears off and symptoms return.
“Off” periods are more common as the disease progresses and people take medication for a longer period of time.
Motor fluctuations in patients with Parkinson’s disease have been studied extensively. But little is known about non-motor symptoms during “on” and “off” periods.
Motor wearing-off includes the re-emergence of motor symptoms such as tremor, rigidity, and bradykinesia (slowness of movement). Non-motor symptoms include anxiety, fatigue, and depression.
Non-motor symptoms have a significant impact on a patient’s quality of life, as the burden can often be more disabling compared to motor symptoms.
Researchers have developed tools to assess wearing-off in Parkinson’s patients. In particular, the wearing-off questionnaire (WOQ-19) has been used in studies as a screening tool to identify which patients experience the wearing-off phenomena.
The team conducted a cross-sectional study to assess the impact of motor and non-motor wearing-off on daily activities and quality of life in Parkinson’s patients. All patients were evaluated using the movement disorders society unified Parkinson’s disease rating scale (MDS-UPDRS, to follow disease progression), the WOQ-19, and the Parkinson’s disease questionnaire-8 (PDQ-8) to assess quality of life.
Among the 271 patients included, 73.4% had wearing-off. Researchers then classified those patients according to the type: 63.8% had mixed wearing-off (motor and non-motor), 32.7% motor, and 3.5% non-motor.
As expected, the MDS-UPDRS part I total score — which assesses non-motor aspects of daily living — was higher (worse) in the non-motor wearing-off group. Interestingly, there were no differences in MDS-UPDRS part I score between patients in the mixed wearing-off group and those who did not experience wearing off.
“This finding suggests that patients with motor wearing-off may have a lower overall burden of non-motor symptoms, while patients with mixed or no wearing-off have similar burdens,” researchers said. “Conversely, patients with non-motor fluctuations also have a higher burden of non-motor symptoms.”
Parkinson’s patients in the non-motor wearing-off group also had the worst score in the PDQ-8, followed by patients in the mixed wearing-off group. On the other hand, patients with no wearing-off and those with only motor wearing-off had a better quality of life.
“[T]he present study shows that both motor and non-motor fluctuations have an impact on activities of daily living and quality of life. However, the presence of non-motor fluctuations did significantly worsen the quality of life,” the authors wrote.
“The identification and assessment of non-motor fluctuations in the day-to-day clinical practice could result in the improvement of the quality of life of patients with [Parkinson’s disease],” the team concluded.