Biostatistician Research on Healthcare Performance (RESHAPE), INSERM U1290, Université Claude Bernard Lyon 1, Lyon, France LYON, France
Background: Isotretinoin exposure is associated with teratogenic effect, psychiatric and metabolic disorders. French prescription and dispensation guidelines related to this acne treatment recommended to use it as a second-line treatment, to renew the prescription for each dispensation and to perform laboratory monitoring of lipid and hepatic enzymes before and during treatment. In June 2015, a decision of regulatory authorities restricted treatment initiation to dermatology specialist.
Objectives: To evaluate the compliance of oral isotretinoin use to national guidelines between 2014 and 2021 in France, using the reimbursement database of all French residents' health-related care.
Methods: A retrospective cohort study was conducted using data from the National Health Data System and included all new users of oral isotretinoin between 2014 and 2021. Initiation corresponded to the first dispensation of isotretinoin with no prior dispensation for at least 12 months. Four outcomes were assessed: the initial prescription by a dermatology specialist, the second-line prescription after systemic antibiotic and/or topical therapy, the renewal of prescription for each dispensation, and carrying out lipid and hepatic enzymes laboratory monitoring. The effect of the decision of June 2015 on the direct (step) and prolonged (trend) changes in the proportion of treatment initiated by a dermatology specialist was assessed using a monthly interrupted time series analysis (ARIMA model). We expressed the results of this model as a change in proportion (%), 95% confidence intervals (95%CI), and p-value (p).
Results: We included 552,221 patients (mean age: 24 years; sex ratio: 0.95). The percentage of treatment initiated by a specialist increased from 88% to 92% after June 2015. Time series analysis showed a significant immediate increase (2.93%, 95%CI 1.71% to 4.15%, p< 0.01) but no significant change in trend over time (0.08%, 95%CI -0.23% to 0.09%, p=0.39). Within 12 months before initiation, 63% of patients received at least one dispensation of systemic antibiotic therapy, 49% at least one dispensation of topical therapy and 42% at least one dispensation of each. In average, 86% of dispensations had a new prescription. Before treatment initiation, 80% of patients had lipid and hepatic enzymes monitoring and 41% during treatment.
Conclusions: Guidelines on initial prescriber and renewal of prescription were mostly respected while compliance to guidelines on second-line prescriptions and biological monitoring were inadequate.
