Antidepressant prescribing patterns and adverse events following introduction of a National Prescribing Indicator to monitor dosulepin usage in Wales.

AIMS: Limiting use of the antidepressant dosulepin has been encouraged due to associated risks of toxicity. In April 2011, the All Wales Medicines Strategy Group introduced a National Prescribing Indicator (NPI) to monitor dosulepin usage. The aim of this study was to investigate antidepressant prescribing patterns, and selected adverse events in patients prescribed dosulepin following introduction of the NPI. METHODS: An e-cohort study was conducted. Adult patients receiving regular dosulepin prescriptions between October 2010 and March 2011 were included. Characteristics of patients who were continued on dosulepin, were switched to an alternative antidepressant or whose dosulepin was discontinued following introduction of the NPI were compared. RESULTS: In total, 4121 patients were included. Of these, 1947 (47%) continued dosulepin, 1487 (36%) were switched and 692 (17%) discontinued. Of the 692 who discontinued, 92% did not receive a prescription for another antidepressant during the follow-up period. Patients whose dosulepin was discontinued were older and were less commonly coprescribed benzodiazepines. During follow-up, recorded incidence of selected adverse events was low across all groups and no significant difference was observed. CONCLUSION: Over half of patients had discontinued dosulepin at the end of the period when the NPI was in place. Further interventions may have been required to have a greater impact on prescribing. This study provides some reassurance that dosulepin discontinuation can be a successful strategy, and that the risk of the adverse events investigated was unlikely to have been greater in those who had dosulepin discontinued than in those in whom dosulepin had been continued.

Estimated Versus Observed Expenditure Associated with Medicines Recommended by the All Wales Medicines Strategy Group.

OBJECTIVES: The All Wales Medicines Strategy Group (AWMSG) appraises the clinical and cost effectiveness of new medicines being considered for National Health Service (NHS) prescribing in Wales (UK). The aim of this study was to compare the estimated expenditure on selected medicines submitted by pharmaceutical companies for appraisal with the observed expenditure on these medicines following recommendation. METHODS: Medicines appraised and recommended for use in NHS Wales by AWMSG between May 2005 and December 2013 were identified for inclusion in the study. Estimates of expenditure were obtained from company submissions to AWMSG. Primary and secondary care dispensing databases were used to obtain observed expenditure. The Wilcoxon matched-pairs signed rank test was used to compare the observed and estimated expenditure in each of the 3 years after introduction of the medicine. RESULTS: Forty-nine medicines appraised and recommended by AWMSG during the period of interest were included in the study. Median estimated and observed expenditure in each of the 3 years post-recommendation were as follows: year 1 £86,400 and £47,300; year 2 £175,500 and £73,200; year 3 £212,100 and £78,900 (p = 0.03, p = 0.006 and p = 0.001, respectively). The expenditure on 42 of the 49 medicines (82%) was overestimated in at least one of the 3 years post-introduction, with 32 (65%) overestimated in all 3 years. CONCLUSION: In their applications for health technology appraisal, pharmaceutical companies tended to overestimate the expenditure of the majority of medicines recommended by AWMSG. These findings have implications for the assessment of predicted expenditure as part of the process of medicines appraisal in Wales.