Quantitative tremor analysis can distinguish Parkinson disease (PD) from dopamine receptor blocking agent-induced parkinsonism, according to a recent study. Dual axis accelerometry was used to quantify tremor in 158 patients with parkinsonism; 62 had PD and 96 were clinically diagnosed with dopamine receptor blocking agent-induced parkinsonism. Tremor was measured while subjects rested arms (resting tremor), outstretched arms in front (postural tremor), and reached a target (kinetic tremor). Researchers found:
- Patients with dopamine receptor blocker induced parkinsonism had lower resting and postural tremor amplitude.
- There was a substantial increase of kinetic tremor amplitude in both disorders.
- Postural and resting tremor in subjects with dopamine receptor blocking agent-induced parkinsonism was prominent in the abduction–adduction plane.
- In contrast, the PD tremor had equal amplitude in all 3 planes of motion.
- Tremor frequency was comparable in both groups.
Shaikh AG. Tremor analysis separates Parkinson’s disease and dopamine receptor blockers induced parkinsonism. [Published online ahead of print February 22, 2017]. Neurol Sci. doi:10.1007/s10072-017-2852-6.