HIV-seronegative Drug Users Research Articles

The effect of HIV infection on overdose mortality

To quantify the association of HIV infection with overdose mortality and explore the potential mechanisms. A prospective cohort study. A total of 1927 actively injecting drug users who were HIV seronegative at baseline, of whom 308 later HIV seroconverted, were followed semi-annually for death from 1988 to 2001. Survival analyses using marginal structural and standard Cox models were used to evaluate the effect of HIV infection on the risk of overdose mortality. Overdose death rates were higher in HIV-seropositive than HIV-seronegative drug users: 13.9 and 5.6 per 1000 person-years, respectively (P < 0.01). The hazard ratio (HR) was 2.54 [95% confidence interval (CI) 1.47, 4.38] for the marginal structural model and 2.06 (95% CI 1.25, 3.38) for the standard Cox model, both adjusted for demographics, drug injection characteristics, alcohol abuse, substance abuse treatment, and sexual orientation. Adjusting for possible time-varying mediators (i.e. drug use, medical conditions and healthcare access) in extended marginal structural models reduced the effect of HIV on overdose mortality by 30% (HR 1.82, 95% CI 1.01, 3.30). Abnormal liver function was associated with a higher risk of overdose mortality (HR 2.00, 95% CI 1.05, 3.84); adjustment for this further reduced the effect of HIV on overdose mortality. HIV infection was associated with a higher risk of overdose mortality. Drug use behavior, systematic disease and liver damage associated with HIV infection appeared to account for a substantial portion of this association. The data suggest a group to target with interventions to reduce overdose mortality rates.

Influence of depressed mood on neuropsychologic performance in HIV-seropositive drug users.

Some studies point out that depression affects the performance of HIV patients in neuropsychological tasks, but at present this effect is not clear. The purpose of the present paper was to study whether the presence of symptoms of depression affects the neuropsychologic performance of seropositive drug users in tasks of attention/concentration, learning and memory, language, construction and visuospatial function, speed of motor performance, cognitive flexibility, manual skill and concept formation and reasoning. In order to carry out this research a sample consisting of 127 male volunteer subjects was used. These subjects were distributed in four groups: one group consisted of HIV-seropositive drug users with symptoms of depression (n = 33); the second group consisted of HIV-seropositive drug users without symptoms of depression (n = 47); the third group was formed by HIV-seronegative drug users with symptoms of depression (n = 15) and the fourth group was formed by HIV-seronegative drug users without symptoms of depression (n = 32). The results reveal the effect of symptoms of depression (evaluated by the Beck Depression Inventory) on the neuropsychologic performance of seropositive drug users. This effect, however, was not observed in the seronegative group. These findings lead us to suggest that symptoms of depression constitute a risk factor for presenting neuropsychologic disturbances in seropositive subjects, which could well be acting as a factor that foments the neuropsychological effects of HIV.

Comparison of self-reported injection frequencies for past 30 days and 6 months among intravenous drug users

In this study we compared two parallel self-reported measures that now are being used to assess the recent frequency of intravenous drug use. The study sample consisted of 926 HIV seronegative drug users recruited for participation in HIV research. During a standard interview with each drug user, we first asked about injections in the past 30 days, and then about injections in the past .6 months. The correlation between reports on the past 6 months and the past 30 days was appreciable when all injections were considered (Spearman correlation coefficient ϱ = 0.78). It increased when the sample was restricted to subjects who reported injections in the past month (ϱ = 0.88). This restriction resulted in a 15% reduction of the sample size, since 137 participants reported drug use in the previous 6 months but not in the previous 30 days. Concordance tended to be slightly higher for reported frequencies of heroin injections than for cocaine injections, and for men as compared to women. The observed levels of concordance indicate that in many instances both approaches can yield comparable results. Nevertheless the choice of 30 days recall vs 6 months recall must rest upon the specific research questions of each investigation.

The Edinburgh cohort of HIV-positive drug users

A two-tone auditory event-related potential (AEP) task was used to examine brain function in 206 HIV-positive individuals (infected by intravenous drug use) approximately 6-7 years after initial infection. Multiple regression analysis of AEP latency and amplitude components showed only small effects of past medical and psychiatric history, current symptoms and drug use on electrophysiological responses. HIV-positive patients had longer latency and reduced amplitude of the P300 (P3) component of the AEP compared with a normal control group, but were electrophysiologically similar to a matched control group of HIV-seronegative drug users. However, a lower P3 amplitude was seen in patients in Centers for Disease Control stage IV. One-year follow-up of 103 patients (50%) found significant lengthening of P3 latency in patients with stage IV disease but not in those with stage II or stage III disease. The results suggest that brain involvement in HIV infection can be detected electrophysiologically after the clinical diagnosis of stage IV disease.