Lifetime antipsychotic-drug exposure, dyskinesia and related movement disorders in the developmentally disabled

The relationship between dyskinesia and related movement disorders was examined as a function of cumulative exposure to antipsychotic drugs (APD). Lifetime drug-exposure histories were obtained for 162 developmentally disabled (DD) persons; drug-exposed groups were compared to nondrug-exposed groups. There were no statistically significant relationships between dyskinesia and the amount of lifetime APD exposure, nor between dyskinesia and the number of long-term APDs, mean exposure, peak exposure, recency of exposure, duration of exposure, changes in medication levels, number of drug interruptions, age, gender, cerebral palsy, epilepsy, or IQ. Of the other movement disorders, a positive relationship was noted only between akathisia and long-term APD exposure; the increased prevalence of akathisia persisted beyond four years after APD withdrawal.