Injecting psychostimulant drugs is associated with acquiring HIV infection amongst injecting drug users in St Petersburg, Russia, according to an article published in the April 4th edition of AIDS. The investigators found a very high level of HIV prevalence amongst individuals screened for entry into their study, and an HIV incidence rate of 5%. In addition, they established that the overwhelming majority of injecting drug users were sharing injecting equipment and that many female drug users were selling sex.
Social and economic factors associated with the collapse of the Soviet Union fuelled an explosion of injecting drug use in Russia during the 1990s. This, in turn, led to an expansion of the HIV epidemic, and it is estimated that HIV prevalence amongst injecting drug users in St Petersburg increased from 4% in 1999 to 30% in 2002.
Earlier studies have shown that both heroin and psychostimulant drugs such as amphetamines are being injected and that 75% of all individuals infected with HIV in Russia are injecting drug users.
Investigators wished to determine the incidence of new HIV infections amongst injecting drug users in St Petersburg and to describe the demographic and behavioural characteristics associated with new HIV infections.
Therefore, between March and December 2002 a total of 900 injecting drug users were enrolled to their study. Individuals were tested for HIV infection and 270 (30%) were excluded from further analysis because it was found that they were already infected with the virus.
A total of 520 individuals were eventually enrolled to the longitudinal study. Most (70%) were male, 80% had had a secondary education or higher, 62% were unemployed or under-employed and 68% lived with their parents or other relative. The median age was 24 years.
In the month prior to recruitment, 96% had injected heroin and 37% had injected both heroin and psychostimulants. Only 9% had injected psychostimulants alone.
Most of the individuals reported sharing injecting equipment, with 79% sharing needles.
Selling sex was reported by 50 women (33%) and 18 men (5%). The median number of sexual partners in the previous six months reported by women who sold sex was five. Overall, the investigators noted that individuals who reported injecting psychostimulants had more sexual partners (median three), than those who did not (median two).
Of the 520 people who entered the study, 417 were still being followed at month twelve or had been diagnosed with HIV. This gave a retention rate of 80%. Of the individuals who were lost, 11% died, 30% were imprisoned, 3% were hospitalised and 3% stopped using drugs.
During the twelve months of the study 20 individuals tested HIV-positive, giving an HIV incidence rate of 4.5 per 100 person years. Amongst people who injected psychostimulant drugs three or more times a week, the incidence was 20 per 100 years compared to only 3 per 100 person years amongst individuals who only injected heroin.
Reporting larger numbers (three or more) or sexual partners and selling sex were both associated with higher HIV incidence – the incidence for the 50 women selling sex was 10 per 100 person years compared to 1 per 100 person years amongst women who did not sell sex.
In multivariate analysis, injecting psychostimulant drugs three or more times a week was the only factor which was found to be significantly associated with incident HIV infection (p = 0.0007).
“In conclusion, psychostimulant use…was the primary HIV acquisition correlate” write the investigators.
Kozlov AP et al. HIV incidence and factors associated with HIV acquisition among injection drug users in St Petersburg, Russia. AIDS 20: 901 – 906, 2006.