Evidence of slow-release morphine sulfate abuse and diversion: epidemiological approaches in a French administrative area.

Slow-release oral morphine sulfate (SM) is one of the most abused prescription opioids in France. However, the regional feature of the abuse of morphine is poorly documented. To investigate the abuse of SM in a French administrative region, a multisource approach was applied. The first approach was based on SM exposition at national and regional level using the OPPIDUM survey. In a second approach, we analyzed a drug reimbursement database to assess the magnitude of SM abuse in Languedoc-Roussillon (LR) region. A clustering method was applied to classify patients and to describe the profile of deviant patients. The third approach was based on a self-administered anonymous questionnaire, proposed to patients seen in addiction care centers in the LR region and consuming oral SM. The OPPIDUM study showed that in most regions, where the prevalence of heroin use is higher than the national average of 9.1%, SM consumers were fewer. With the clustering method, three subgroups were identified. One of them gathered 35 users (3.2%) with a deviant behavior characterized by significantly more dispensations, dispensing pharmacies, and prescribers. These subjects were mainly men, younger, and more consumers of benzodiazepines and opioid maintenance therapy than the others. The third study allowed specifying that SM was mainly injected (93.7%), bought in the street (80%), and used because of unavailability and the poor quality of heroin (33.9%). The three proposed approaches are complementary and help to clarify the abuse of oral SM, while assessing the motivations of this abuse.