IMPROVED REGIONAL CEREBRAL BLOOD-FLOW IN CHRONIC COCAINE POLYDRUG USERS TREATED WITH BUPRENORPHINE

Chronic cocaine and polydrug abuse have been associated with regional abnormalities in cerebral perfusion. The authors have previously demon strated that these abnormalities are partially reversible after drug a ddiction treatment with buprenorphine. This study was designed to sepa rate the effect on cerebral perfusion of abstinence from drug use from that of buprenorphine directly. Methods: Fifteen cocaine- and heroin- dependent men were studied with Tc-99m-hexamethylpropyleneamine oxime (HMPAO) brain SPECT. The men, all part of an inpatient drug abuse trea tment research program, were randomly assigned after detoxification to receive placebo or either 6 or 12 mg daily buprenorphine treatment. S PECT studies were performed at baseline, after maximum dosage was reac hed and after tapering off the study drug. Studies were compared visua lly with regard to the number and location of perfusion defects by rev iewers blinded to treatment assignment. Results: Subjects receiving bu prenorphine had a significant reduction in the number of defects per s tudy between baseline and maximum buprenorphine dose as compared with those receiving placebo (decrease of 4 +/- 5.4 versus increase of 4.8 +/- 4.7, p = 0.006). These differences were dose-related. Improvement with buprenorphine was temporary, with return to baseline after taperi ng off. Conclusion: Buprenorphine treatment, and not abstinence from d rug use atone, leads to improvement in regional cerebral perfusion abn ormalities in chronic cocaine- and heroin-dependent men.