Change in the regulatory framework for zolpidem: what is the impact on the landscape of the prescription of sedative medications? The French national ZORRO study.

Istvan, Marion; Caillet, Pascal; Rousselet, Morgane; Guerlais, Marylène; Laforgue, Edouard-Jules; Gérardin, Marie; Jolliet, Pascale; Feuillet, Fanny; Victorri-Vigneau, Caroline

AIM In recent years, zolpidem has been the subject of numerous reports of misuse, abuse and dependence. In view of these risks, the French drug agency (ANSM) decreed in April, 2017 the implementation of secure prescription pads. The objective of this study was to evaluate the impact of this regulatory measure on the prescription of zolpidem and other sedative medications (zopiclone, benzodiazepines and antihistamines) in long-term users of zolpidem and factors associated. METHODS We performed an historical cohort study using data from the Generalist Sample of Beneficiaries (EGB). All patients aged over 18 years old who were long-term users (at least 3 months) before the measure were enacted. We analysed the reimbursement trajectories of zolpidem, zopiclone, benzodiazepines and antihistamines (hydroxyzine and alimemazine) up to two years after the measure using a state sequence analysis. RESULTS Overall, 2,502 patients were analysed. A four-cluster typology was identified: continuation of zolpidem (n=1,044, 42%), discontinuation of sedative medications (n=766, 31%), change to zopiclone (n=537, 21%) and change to hypnotic benzodiazepines (n=155, 6%). The most frequently prescribed hypnotic benzodiazepine was lormetazepam. We identified age, sex, treatment for psychiatric or addictive disorder and volume of zolpidem use before the measure as factors associated to different reimbursement trajectories after the regulatory change. CONCLUSION The regulatory change for zolpidem prescriptions reduced exposure to zolpidem among long-term users and had also a broad impact on prescriptions of other sedative medications. Switching to other medications that also present a potential risk of abuse or dependence should be carefully monitored.