Needles and the damage done: reasons for admission and financial costs associated with injecting drug use in a Central London Teaching Hospital.

Objectives: To establish the clinical reasons for inpatient admissions among injecting drug users. To determine the frequency of behavioural issues during their care and to estimate the financial implications of injecting drug use to the health service.

Methods: Retrospective cohort study at University College London Hospital. Clinical, laboratory and financial data were extracted from case notes and electronic records. The cost of each admission was compared to the income received for the period of care.

Results: 124 injecting drug users required 191 admissions between 2005 and 2009. Skin and soft tissue infections (58%) and pneumonia (18%) were the commonest reasons for admission. Bacteraemia at admission was often not accompanied by an inflammatory response. Exposure to HIV (4%), hepatitis B (49%) and C (84%) was common. Drug misuse (16%) during admission was frequent. The cost to the NHS of treating soft tissue infections in drug users was approximately £77 million per annum. After a median follow-up of 40 months, 10 patients (8%) had died. All deaths were attributable to drug use.

Conclusions: Bacterial and viral infections are largely responsible for the significant mortality and morbidity of injecting drug users presenting to secondary care. The financial burden to the NHS is substantial.