Introduction: After the onset of the HIV epidemic, the hope arose that the "harm reduction" approach of the Amsterdam "low-threshold" methadone programs would have a function in controlling the spread of HIV among injecting drug users (IDUs).
Methods: To find evidence for this assumption, 386 IDUs participating in an HIV study between 1985 and 1989 were studied. Long-term regular participants in low-threshold methadone programs were compared with short-term and/or irregular participants.
Results: Controlling for possible confounders, long-term regular participants had a slightly increased but not statistically significant risk of being HIV infected. With regard to current drug use, they injected daily and shared needles as often as did short-term and/or irregular participants.
Conclusions: The results suggest that the Amsterdam low-threshold methadone programs fail to diminish HIV risk behavior. If these programs want to have a positive effect on the spread of HIV, expansion of existing HIV prevention efforts, an increase in the daily methadone dose level, and measures to enforce regular attendance may be required.