[Trend in buprenorphine and methadone shopping behavior in France from 2004 to 2014]. / Diminution de la prévalence du docteur shopping de la buprénorphine entre 2004 et 2014 en France.

INTRODUCTION: The opioid maintenance treatments (OMT) are widely misused and diverted in many countries. Doctor shopping represented the main way to obtain high quantities of opioids in abuse/diversion. The aim of this study was to assess the trends in the prevalence of doctor shopping for high dosage buprenorphine (HDB) and methadone (MTD) from 2004 to 2014 by using the French Health Insurance claims. METHODS: This was a cross-sectional study of patients treated by OMT (High Dosage Buprenorphine or Methadone) between 2004 and 2014 from a representative sample of the French Health Insurance claims. Doctor shopping was defined as at least 1 day of overlapping prescriptions, written by at least 2 different prescribers and filled in at least 3 different pharmacies. RESULTS: HDB patients were more likely men (77.9 % in 2014) with a mean age ranged from 33.4±7.6 years in 2004 to 39.5±9.3 years in 2014, P<0.001. MTD patients were also more likely men (73.9 % in 2014) with a mean age ranged from 33.5±6.9 years in 2004 to 37.1±8.5 years in 2014, P<0.001. In 2014, 35 % of HDB patients and 36 % of MTD patients presented a long-term disease which was most frequently a mental health disorders. The prevalence of doctor shopping for HDB decreased from 2004 to 2014 (12.6 % versus 3.9 %, P<0.001). The prevalence of doctor shopping for MTD was very low during the period study (0.2 % to 0.5 %). Overall, the prevalence of doctor shopping was higher for HDB than for MTD whatever the year (P<0.001) of the study. CONCLUSION: Doctor shopping for HDB decreased significantly during the last decade while doctor shopping for MTD remained nearly inexistent even if it could be underestimated because of dispensations in specialized centers and in hospitals not comprised in the insurance claims. The low rates of doctor shopping reported in these last years could result from the guidelines for good practices in OMT use made in 2004 and the adjustments of ANSM (French National Agency for Medicines and Health Products Safety) for HDB best use made in 2011.

Satellite glial cell proliferation in the trigeminal ganglia after chronic constriction injury of the infraorbital nerve.

We have examined satellite glial cell (SGC) proliferation in trigeminal ganglia following chronic constriction injury of the infraorbital nerve. Using BrdU labeling combined with immunohistochemistry for SGC specific proteins we positively confirmed proliferating cells to be SGCs. Proliferation peaks at approximately 4 days after injury and dividing SGCs are preferentially located around neurons that are immunopositive for ATF-3, a marker of nerve injury. After nerve injury there is an increase GFAP expression in SGCs associated with both ATF-3 immunopositive and immunonegative neurons throughout the ganglia. SGCs also express the non-glial proteins, CD45 and CD163, which label resident macrophages and circulating leukocytes, respectively. In addition to SGCs, we found some Schwann cells, endothelial cells, resident macrophages, and circulating leukocytes were BrdU immunopositive.

Chronic constriction injury of the infraorbital nerve in the rat using modified syringe needle.

Here we report a method for performing a chronic constriction injury (CCI) of the infraorbital nerve (ION) in the rat as a component of a chronic pain model. The surgical approach to the ION is described together with the use of a modified dental syringe needle that simplifies placing two chromic gut ligatures around the ION. This method makes the surgical procedure easier, the nerve injury more consistent across animals and reduces secondary damage to the ION and surrounding tissue. Pain behavior testing together with immunostaining for markers of nerve injury in the spinal trigeminal nucleus show the suitability of this procedure as a model of orofacial pain.