Trends in spontaneous adverse drug reaction reports to the French pharmacovigilance system (1986-2001).
Résumé
BACKGROUND: The French pharmacovigilance system is based on a network of 31 regional centres located in teaching hospitals and coordinated by the French Medicines Agency ("Agence Française de Sécurité Sanitaire des Produits de Santé" [Afssaps]). Since 1984, they have shared a common database of adverse drug reactions (ADRs) that are spontaneously reported by healthcare professionals. The objective of this study is to describe the characteristics of the reports and the reporting trends in the French pharmacovigilance spontaneous reporting database from 1986 to 2001. METHODS: All the reports from January 1986 to December 2001 were included. Drugs and ADRs were translated to anatomical therapeutic chemical (ATC) codes and MedDRA classifications, respectively. RESULTS: The total number of reports was 197 580 over the 16-year period, with linearly increase over time. The median (interquartile range [IQR]) age of the patients was 53 (34-70) and the male/female ratio was 0.82. The median (IQR) time between the date of occurrence of the ADR and the date of report was 73 days (34-166). The reporter was a specialist in 74% of the reports and a general practitioner in 17%. The annual rate of reporting according to medical demography strongly increased for the specialists, especially since 1994. At least one ADR was considered as serious in 44.8% of the reports. The ADRs were most frequently related to nervous system drugs (23%), followed by cardiovascular drugs (19%) and systemic anti-infectives (17%). The latter class had the fastest progression mostly due to antiretroviral therapy since 1996. According to the Medical Dictionary for Regulatory Activities (MedDRA) coding, the system organ most often reported was skin and subcutaneous tissue disorders (29%), followed by nervous system disorders (19%), gastrointestinal disorders (12%), blood and lymphatic system disorders (12%), vascular disorders (12%) and general disorders and administration site conditions (12%). DISCUSSION: All spontaneous reporting systems are affected by under-reporting. One of their goals is to generate early signals, which might be more affected by reporting bias than by under-reporting. Some improvements should be made in the design of the French database, but data collected since 1986 constitute an essential tool for the routine work of the 31 pharmacovigilance centres. CONCLUSION: This first description of the data of the French pharmacovigilance database involving all drugs and ADRs shows an increasing tendency to reporting over time, especially in specialists and for systemic anti-infective drugs. The database that uses hierarchical international classifications for drugs and adverse reactions may be used for further studies and could be the basis for an automatic signal generation system.