Background: To evaluate the severity of choreoathetoid movements in cocaine dependent (CD) subjects and age-matched normal control subjects.
Methods: Choreoathetoid movements were evaluated using the Abnormal Involuntary Movement Scale (AIMS) in samples of 71 CD, 56 normal control, and 9 amphetamine-dependent male subjects.
Results: The CD subjects had a significantly increased nonfacial (limbs plus body) AIMS subscore. When the nonfacial AIMS scores of the two groups were compared in relation to age, a significant age by diagnosis interaction was observed, indicating that the differences between groups were most marked in the younger age groups. The facial AIMS scores were also increased but only in the youngest CD cohort (under 32 years of age). The comparison group of 9 younger amphetamine-dependent subjects also showed increased AIMS scores.
Conclusions: Increases in choreoathetoid movements in younger cocaine and amphetamine-dependent subjects may be related to their psychostimulant use. The absence of differences in choreoathetoid movements between the older CD subjects and normal control subjects may represent an age-related self-selection effect.