Hospital discharges and 30-day case fatality for drug poisoning: a Danish population-based study from 1979 to 2002 with special emphasis on paracetamol

Objective. To examine the number of hospital discharges and 30-day case fatalities due to drug poisoning based on data from a Danish County Hospital Discharge Registry from 1979 to 2002. Methods. All patients with a hospital discharge diagnosis of drug poisoning were identified and separated into groups taking: (1) opioid analgesics; (2) non-opioid analgesics; (3) anxiolytics; (4) antidepressants; (5) antipsychotics; or (6) non-specified. Paracetamol and salicylate were analysed separately. From 1994 to 2001, the total amount of drugs sold in the county was identified from a national drug database. Results. A total of 13,432 patients with a median age 41.5 years at discharge of whom 59% were females accounted for 20,249 discharges for drug poisoning. The overall number of discharges remained essentially stable around 170 discharges per 100,000 inhabitants per year. From the mid-1990s, paracetamol became the most frequently used drug in poisoning with the largest increase in female teenagers. Thirty-day case fatality in poisoning with opioids was 3.6% compared with around 1% in other drug categories. For most drug categories, a sale of around 80,000 defined daily doses was associated with one hospital discharge due to drug poisoning. Conclusion. The overall number of hospital discharges remained stable and seems primarily related to amount of drugs available. With almost 10 years delay, the easier access to paracetamol was followed by an increase in hospitalisation due to poisoning with paracetamol. However, although the majority of hospitalisations were found in the younger age group, the highest mortality was seen among the elderly.