Researchers from Imperial College London, the Health Protection Agency, Medical Research Council and GlaxoSmithKline have analysed the numbers of opiate and injecting drug users who had overdoses, to see if it was possible to model long term trends for the number of opiate or injecting drug users.
They also found the number of overdoses among opiate and injecting drug users has risen nearly 100 fold in thirty years from around 9 in 1968 to more than 900 by 2000.
Dr Matthew Hickman, from Imperial College London, based at Charing Cross Hospital, and one of the authors of the research, comments: "These results could help provide better data on the true number of drug users in the population and help provide the government with a far better surveillance tool than they currently have. Often the true level of drug use is hidden within populations, but this method could be used to provide a more accurate picture."
The researchers analysed data for England and Wales between 1968 and 2000, looking at 7375 deaths in people aged 15-44, which had been coded as drug misuse or accidental opiate overdose, and used a back calculation method to estimate long term trends.
The results suggested that there have been two epidemic periods with the numbers of new opiate and injecting drug users having increased three-fold between 1975 and 1979 and up to five to six-fold between 1987 and 1995. Models looking at recent data suggest the numbers of new opiate users may have recently declined.