Effects of expiring reimbursability of pentaerythrityl tetranitrate (PETN, pentalong®) on anti-anginal therapy: an observational study.

PURPOSE: Pentaerythrityl tetranitrate (PETN) was the most commonly prescribed long-acting nitrate in Germany. We aimed to assess whether the discontinuation of PETN reimbursability in 2011 resulted in alternative prescriptions of anti-anginal medications or in a discontinuation of anti-anginal therapy. METHODS: This is an observational study using health claims data from one German federal state analysing all patients discontinuing a PETN treatment. Patients starting a new alternative anti-anginal treatment (long-acting nitrates, molsidome, ivabradine and ranolazine) were compared with patients without a new anti-anginal treatment with respect to use of short-acting nitrates, beta blockers (BBs) and calcium channel blockers (CCBs). RESULTS: Out of 12,909 patients, 12,763 (99%) discontinued PETN until 12/2012. Of these, 52% started an alternative anti-anginal treatment, 43% did not receive any alternative treatment and 5% were excluded from analysis. Before termination of PETN reimbursability, 65% of patients received BBs, 29% CCBs and 10% short-acting nitrates. In patients started on alternative anti-anginal treatment, prescription rates for short-acting nitrates, BBs and CCBs remained constant after discontinuing PETN. In patients without any alternative anti-anginal treatment, prescription rates for BBs and CCBs did not change meaningfully (<3%), and prescription rates for short-acting nitrates decreased from 9% to 6%. CONCLUSIONS: Half of the patients discontinued PETN without alternative. This did not lead to increased prescription rates of standard IHD medications or total medication number indicating that there might still be a high percentage of ischaemic heart disease patients treated unnecessarily with long-acting nitrates. The undertreatment with prognostically relevant first-line medications indicates a need for better guideline implementation activities.