Timed motor tests can detect subtle motor dysfunction in early Parkinson's disease

Area of Science:

• Neurology
• Movement Disorders
• Diagnostic Tools

Background:

• Early diagnosis of Parkinson's disease (PD) is crucial for initiating timely neuroprotective therapies.
• Subtle motor dysfunction may be present even in the earliest stages of PD.
• Identifying reliable diagnostic tools for early PD is a significant clinical need.

Purpose of the Study:

• To evaluate a timed motor test (TMT) battery for detecting subtle motor dysfunction in early, dopa-naive PD patients.
• To assess the TMT battery's ability to identify motor deficits in the clinically unaffected limb of hemiparkinsonian patients.
• To determine the diagnostic accuracy of individual TMTs, particularly the pegboard dexterity test.

Main Methods:

• Assessed 107 early PD patients (symptom duration ≤2 years, dopa-naive) and 100 controls using eight TMTs.
• TMTs included walking, writing, pegboard performance, finger tapping, and diadochokinesis.
• Receiver Operating Characteristic (ROC) curves were used to evaluate diagnostic discrimination.

Main Results:

• The pegboard dexterity test demonstrated the highest diagnostic accuracy (AUC 0.97) for distinguishing PD patients from controls.
• This test showed reasonable accuracy (AUC 0.73) in identifying motor dysfunction in the clinically unaffected limb of hemiparkinsonian patients.
• The pegboard test achieved 95% sensitivity and 89% specificity in differentiating early PD patients.

Conclusions:

• The pegboard dexterity test is a sensitive, inexpensive, and effective instrument for detecting motor dysfunction in early PD.
• This TMT may serve as a valuable diagnostic tool in clinical practice for early symptomatic PD assessment.
• The pegboard test could be incorporated into screening batteries for populations at risk of PD.