On-site Evaluation of Substances Consumption on Opiate Maintenance

In a retrospective cohort study of methadone users performed through data obtained from a primary care prescription registry in Tayside, Scotland, McCowan et al examined the interaction of patient related factors and prescribing factors at the individual level and assess their independent impact on the risk of both all-cause mortality and drug dependent cause specific mortality (McCowan, Kidd et al. 2009). Overall, 181 (8%) people died among 2378 subjects with a median follow-up of 4.38 years. Overuse of methadone, history of psychiatric admission, and increasing comorbidity were all associated with an increase in all-cause mortality. Longer duration of use (adjusted hazard ratio 0.95, 0.94 to 0.96), history of having urine tested (0.33, 0.22 to 0.49), and increasing time since last filled prescription were protective in relation to all-cause mortality. These factors are likely to be markers of people who are stabilised on maintenance treatment and engaged in monitoring procedures or who have successfully completed a methadone treatment reduction programme. This community based study gives a clear indication of the prescribing, monitoring, and management of patients in OMT and the subsequent impact on all cause and drug dependent mortality. This study provides evidence that recommendations on best practice (including specifically performing UDS) improve patients' outcomes.

Using data from the French "Methaville" trial, Roux et al (Roux, Michel et al. 2012; Roux, Lions et al. 2013) investigated the effect of pre-treatment and in-treatment factors on long-term non-adherence to this OMT. Four pre-treatment predictors of non-adherence were identified: being female, not having stable housing, alcohol consumption and cocaine use. These findings highlight the need to appropriately assess psychoactive drug use when starting OMT, and urine drug testing should be consider as a way to reach this aim.

On the basis of the literature, one would suppose that carrying out UDS would provide an improvement in the management of patients with abuse or addiction and would be helpful, particularly in community office-based settings, as office-based management of opioid dependence grows up (Walley, Alperen et al. 2008). Despite the lack of significant evidence of efficacy, UDS are recommended to assess the use of psychoactive substances when abuse or addiction is suspected.

Inclusion criteria

• For GPs:Professional criteria: to practice as a GP, to be in activity, to practice in general ambulatory practice (in a medical office), to regularly manage patients treated with buprenorphine, to be registered in sector 1, consent for participating to the study
• For patients:

Aged 18 years-old or more, to consult for starting buprenorphine or OMT:

• any patient previously treated by buprenorphine or buprenorphine-naloxone but with his/her treatment interrupted for at least 2 months will be considered as a candidate for a new treatment with buprenorphine or buprenorphine-naloxone
• any patient previously exposed to opiate maintenance drug obtained illegally "in the street" will not be as treated affiliated to a health insurance scheme, not opposed to participate

Exclusion criteria

• For patients: to consult for continuing buprenorphine or for another complain related, to opiate substitution treatment, to be known and yet managed by the GP for an opiate substitutive treatment, to have started buprenorphine in a specialized centre or in a hospital, to be treated with methadone, to be treated with methadone and asking a switch toward buprenorphine