Opioid prescription for terminally ill outpatients in a district of northern Italy: a retrospective survey

Abstract

A retrospective survey of the opioid prescriptions issued for cancer outpatients (2125) of the Treviso district (Veneto Region, northern Italy) during the time period 1993-2000 was carried out with the specific aims to establish the rate of opioid prescription and verify whether terminally ill outpatients (1697) who had died by the end of December 2000 received adequate opioid prescription, as compared with the Defined Daily Doses (DDDs) of opioids suggested by the World Health Organization (WHO) for a standard population. For both women and men, the maximum rate of opioid prescription was at the age of beyond 90 years. Men were more prescribed than women between 60 and 79 years of age, whereas women were more prescribed than men beyond 90 years. Opioid prescriptions concerned only morphine, buprenorphine, and pentazocine. The Anatomical Therapeutic Chemical (ATC)/DDDs analysis of opioid prescriptions indicated that total opioid use increased about 1.7-fold between 1993 and 1996, mainly because of an increase (55.4%) in morphine prescriptions. Afterwards, total opioid use remained stable, with an estimated mean annual value of 108.2+/-6.4 DDDs/million inhabitants/day. Considering terminally ill outpatients who had died by the end of December 2000, oral morphine turned out to be the most commonly prescribed opioid (64% of patients) and, among the three opioids, pentazocine was more prescribed to older patients. From the comparison between the number of "expected opioid DDDs" (i.e. days for which patients should have been prescribed opioids at the WHO recommended DDDs) and the number of prescribed opioid DDDs (i.e. days for which patients had been offered adequate opioid treatment) for individual patients, it could be estimated that only 38.1% of opioid prescriptions were adequate and a mean of 55.8 DDDs of opioids per patient were not prescribed. The opioid prescription inadequacy increased with the length of time from first prescription to patient death. In addition, a questionnaire investigation, conducted in 2001 among general practitioners of the Treviso district to evaluate their attitudes toward opioid prescribing, evidenced insufficient knowledge of general practitioners in theory and use of opioid analgesics in cancer pain management. A total of 104 (32.5%) general practitioners responded and most of them feared opioid side effects, such as respiratory depression (49.6%), constipation (41.7%), and addiction (8.7%). Furthermore, many of the respondents considered opioids capable of reducing the patient length of life (22.2%) and inappropriate to treat pediatric patients (50.6%). About 44% of the respondents experienced external pressure by relatives of patients against opioid prescription and a majority of them (58.2%) considered the recently revised Italian legislation on opioid prescription ineffective for improving their prescribing pattern. In conclusion, present data show that the vast majority of terminally ill cancer outpatients in the Treviso district received inadequate opioid prescriptions in relation to either drug daily dosage or therapy duration. Misconceptions of general practitioners of the district about opioids could contribute to the inappropriate use of these analgesics in cancer pain management. As far as we know, the ATC/DDD methodology for the opioid prescription analysis used in this survey has not been applied before.