Motor Dysfunction as a Prodrome of Parkinson's Disease

Recognition of motor signs in the prodromal stage could help identify those at risk of developing Parkinson's disease (PD).

This study identified motor symptoms and signs in individuals suspected of having PD but who did not have a progressive reduction in the speed and amplitude of finger tapping or other physical signs indicative of bradykinesia.

146 patients, who had symptoms or signs suggestive of PD, were serially evaluated by a movement disorder specialist, using the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part III and video recordings. If the patients 'converted' to PD during follow-up, they were categorized as cases and compared with those who did not meet PD criteria during follow-up (non-cases).

The 82 cases were more likely to have action dystonia or postural/action/rest tremor of a limb (OR 2.8; 95% CI 1.1-7.1; p = 0.02), a reduced blink rate at rest (OR 2.3; 95% CI 1.2-4.6; p = 0.01), anxiety (OR 8.9; 95% CI 2.6-31.1; p < 0.001), depression (OR 7.0; 95% CI 2.9-17.2; p < 0.001), or a frozen shoulder (OR 3.1; 95% CI 1.6-6.2) than the 64 'non-cases'.A reduction of the fast blink rate was common in patients who met the criteria for PD (p < 0.001).

This study emphasizes that motor dysfunction is a component of the clinical prodrome seen in some patients with PD.