Brain perfusion abnormalities associated to drug abuse in recent abstinent patients using SPECT 99m Tc-ethylen-cysteinate-dimer (ECD)

ABSTRACT

Several substances may produce brain perfusion abnormalities in drug-dependent patients. Their mechanism is unclear and several causes might be involved, especially vasospasm in cocaine consumption. Goal: To characterize residual brain perfusion abnormalities in substance-dependent population. We analyzed brain perfusion in 100 dependant patients (DSM-IV criteria) following a month of strict in-hospital abstinence (age:35 +/- 2y.o.; 86 percent men); 55 percent corresponded to poly-drug dependents, mainly to cocaine, alcohol and cannabis; 44 percent mono-drug users, mostly to alcohol. Results: Single Photon Emission Computed Tomography (SPECT) with 99mTc-ethylen-cysteinate-dimer (ECD) was abnormal in 54 percent of the cases, with bilateral cortical hypo-perfusion in 89 percent, focal in 54 percent and diffuse in 46 percent of them, with moderate or severe intensity in 61 percent. The abnormal perfusion group’s age was 38 +/- 12 versus 31 +/- 10 years in the normal SPECT group (P=0.005) with a consumption period of 16 +/- 11 versus 11 +/- 8 years, respectively (P=0.043). Only 29 percent of women had abnormal perfusion versus 58 percent of men (P=0.047). Abnormal brain perfusion in 64 percent of mono and 45 percent in poly-drug dependents (P=0.07). Psychometric tests performed in 25 patients demonstrated association between perfusion defects and cognitive abnormalities. Relative risk for abnormal psychometric test was 2.5 [95 percent;CI=1.1-5.6] for abnormal SPECT. Conclusion: Dependent population after a month of abstinence persists with cortical brain perfusion abnormalities, associated to age, sex and type of drug consumption.