Problem drug use, drug misuse and deliberate self-harm: trends and patient characteristics, with a focus on young people, Oxford, 1993-2006.

BACKGROUND: Drug misuse is related to self-harm and suicide. However, relatively little is known about deliberate self-harm (DSH) in patients with drug problems and whether drug misuse by DSH patients is increasing.
METHODS: We used data collected by the Oxford Monitoring System for Attempted Suicide to study the characteristics of DSH patients with drug problems who presented to the general hospital in Oxford between 1993 and 2006, and who underwent psychosocial assessment at their first presentation in the study period. We also studied trends in problem drug use and drugs misused over this period.
RESULTS: During the 14-year study period, 11,426 patients presented of whom 9,248 underwent psychosocial assessment and it was known whether or not they had a drug problem. Problem drug use was present in 805/9,248 (8.7%) patients. Problem drug use was more common in males (13.6%) than in females (5.3%). Problem drug users were younger, more likely to be socially disadvantaged, to have a personality disorder and comorbid alcohol problems and to have a further episode of DSH within a year. Problem drug use in young females was associated with higher suicidal intent scale (SIS) scores. During the study period, problem drug use and drug misuse increased in females, but not in males. Cannabis and cocaine misuse increased with time.
CONCLUSIONS: Provision of help for DSH patients with problem drug use is particularly challenging due to their complex social and clinical characteristics and increased risk of further self-harm, suicide and accidental death. It may require extensive liaison between different services. The increasing misuse of drugs by female DSH patients and the higher SIS scores of young females are of concern.