Improving insights into medication effect in Parkinson’s disease: lessons from 79 Studies

Wearable studies remain methodologically heterogeneous

The review includes 79 studies and shows marked heterogeneity in wearable devices, body placement, and timing protocols, which limits direct comparison across studies and interpretation of medication effects in Parkinson’s disease.

Current evidence emphasizes limited ecological validity

Most studies assess medication effects in controlled settings and compare single on/off states, usually around one hour after intake; this approach captures short-term effects and provides limited insight into everyday symptom fluctuation.

Real-world gait monitoring detects delayed medication effects

In 41 participants monitored over seven days, real-world step velocity and step length increase significantly 60–120 minutes after medication intake, whereas step time and walking quantity measures do not change significantly.

In the continuing education activity “Improving insights into medication effect in Parkinson’s disease: lessons from 79 Studies,” presented by Emma Packer and organized by Klinik Barmelweid, the speaker examines how wearable technologies can improve assessment of medication effects in Parkinson’s disease. Emma Packer reports that current clinical medication adjustments often rely on brief, infrequent consultations and patient-reported outcomes, which provide only limited insight into symptom fluctuations and treatment response in daily life. She presents a systematic review including 79 studies, identified from 7,388 records, and shows substantial heterogeneity in monitored motor variables, wearable devices, sensor placement, and protocols used to assess medication effects. The review finds that gait is the most frequently studied outcome, that 50 different wearable technologies are used, and that most studies are conducted in controlled laboratory or clinical settings with predominantly short-term comparisons between on and off medication states. Reported medication effects generally include increases in walking speed, step length, and dyskinesia, decreases in tremor amplitude, freezing of gait, and sway frequency, and inconsistent findings for variables such as cadence. Based on these gaps, Emma Packer describes a proof-of-concept real-world monitoring study in 41 participants with Parkinson’s disease using a smartwatch, lower-back sensor, and smartphone over 7 consecutive days to relate medication intake to gait changes. In this study, step velocity and step length increase significantly 60 to 120 minutes after medication intake, whereas step time, total walking time, total step count, and walking bout duration do not change significantly, suggesting that selected gait parameters may serve as sensitive real-world markers of medication effect.