Inhaling heroin, common among Amsterdam heroin users, is thought to account for low OD mortality rates both during and after treatment. Accumulation of methadone, inadequate assessment of tolerance of known clients re-entering treatment and concurrent periods of stress or extreme heroin use when entering treatment are mentioned as possible explanations of the increased risk within the first 2 weeks. An Australian study reported a much higher increase. The modest increase in Amsterdam is explained by low background risk of overdose mortality, low starting dosage and the low threshold to treatment.

Steadily increasing the methadone dosage in a harm reduction setting may be useful in supporting injecting drug users in the process of cessation of injecting and reducing the spread of HIV-infection.

No abstract

Three hundred and eighty six injecting drug users entered into an HIV study through methadone programs over a 40 month period. Differences in oral, intranasal and parenteral use of heroin and cocaine were assessed between four consecutive 10 month intake groups. Heroin smoking and cocaine freebasing were increased in the later intake groups, while there were no significant changes in injecting variables. No relationship between sexual risk behaviour and cocaine freebasing was found. HIV seropositivity was less among cocaine freebasers at 19% compared to 32% among non freebasers. The increase in heroin smoking and cocaine freebasing may have a favourable preventive effect on the spread of HIV among this high risk group.

The relative risk of ACA for psychotic disorders was similar to that for the incidence of psychotic disorders in most ethnic groups from other studies, suggesting that the increased risk of ACA in non-western migrants can mainly be explained by the increased incidence of psychotic disorders in these groups. However, the relative risk of ACA for psychotic disorders among Moroccan migrants was lower than expected on the basis of incidence studies, which suggests that additional factors are relevant, such as illness-related expression and access to and quality of care.