A neuropsychological study of polydrug users
I. Grant, L. Mohns, M. Miller and R. M. Reitan
The long-term neuropsychological effects of persistent nonmedical drug use
are still unknown. In this study, 22 young men, all extensive "polydrug"
users, were examined while free from drugs for an average of 60 days by
means of the Halstead-Reitan Neuropsychological Test Battery. Their
performance was compared to that of age-education-sex-matched
neurologically intact medical patients and a similarly matched group of
neurologically impaired patients. Blind independent ratings of test
protocols by two experienced clinicians judged 41% to 64% of the drug
users, 11% to 26% of the medical patients, and 84% to 89% of the neurologic
patients to be impaired. Interpretation of these results suggests that in
some individuals, heavy "polydrug" use may be associated with
neuropsychological dysfunction, which persists at least an average of two
months beyond cessation of drug use.
