[Evolution of the need and coverage of opioid substitution treatments and needle exchange programmes in Spanish prisons, 1992-2009].

INTRODUCTION Spain is one of the few countries to have widely implemented opioid substitution treatments (OST) and needle exchange programmes (NEP) for drug users in prison. We analyze the evolution of the need, coverage and the timeliness of these interventions in Spain between 1992 and 2009. METHODS Data on the provision of interventions is taken from official publications. The need was calculated by applying multiplicative methods to secondary data from several sources. Coverage was estimated as the quotient between provision and need. Temporal opportunity was estimated by observing the gap between the acme of the incidence of consumption, of HIV infection or need and the curve of provision. RESULTS OST's began to be implemented in 1992. In 2002 they reached their maximum coverage (63.8%) and subsequently stabilized. NEP's started in 1997. Their maximum coverage reached 20.7% in 2006, but halved in a period of two years. The delay between the epidemic acme and the need and maximum intervention coverage was of 8-25 years. CONCLUSIONS OST and NEP introduction in Spanish prisons was a great advance, but the delay in their implementation and the low level of NEP coverage could have limited their potential impact on the improvement of the health of incarcerated drug users. The decline of NEP coverage in recent years is a cause of major concern for the evolution of HIV and Hepatitis C epidemics.