THE INFLUENCE OF DRUG-USE PATTERNS ON THE RATE OF CD4-1-INFECTED INJECTING DRUG-USERS( LYMPHOCYTE DECLINE AMONG HIV)

Objectives: To assess the relationship between various injecting drug use patterns and the rate of CD4+ lymphocyte decline in HIV-l-infected injecting drug users in Baltimore, Maryland, USA. Methods: A cohort o f 605 HIV-1-infected injecting drug users was recruited between 1988 a nd early 1989 in East Baltimore using extensive community outreach tec hniques. The participants were interviewed semi-annually to collect in formation on drug use practices. The outcome measure of interest was t he rate of CD4+ lymphocyte decline between pairs of CD4+ lymphocyte co unts. A mixed model was used to evaluate the relationship between the change in CD4+ lymphocyte count per month and previous CD4+ lymphocyte count and various drug use variables. Results: The 605 HIV-infected i njecting drug users had a median initial CD4+ lymphocyte count of 513 cells x 10(6)/l. Using 3209 paired observations, the mean change in CD 4+ lymphocyte count was -3.2 cells x 10(6)/l per month. The rate of de cline was higher in those with a higher level of CD4+ lymphocytes (P < 0.01) and length of drug use (P < 0.01), but did not vary by injectio n frequency or injection intensity of specific drug types. Although an imal studies have suggested that the pattern of drug administration (c ontinuous versus intermittent) and episodes of withdrawal or overdose might impact the rate of CD4+ lymphocyte decline, this was not observe d in the present study. Conclusion: Patterns of injecting drug use, ba sed on self-report, were not associated with the rate of decline in CD 4+ lymphocytes.