Therapy discontinuation or substitution in patients with cardiovascular disease, switching among different products of the same off-patent active substance: a ‘real-world’ retrospective cohort study

Abstract

ObjectiveThe present study investigated the effects of switching to different products of the same off-patent active substance (brand name or generic) on therapy discontinuation or substitution with another molecule of the same class, in patients with cardiovascular disease treated with statins and antihypertensives in a ‘real-world’ setting.DesignA retrospective cohort study in a ‘real-world’ setting.SettingAnalysis of data performed by integrating administrative databases that included approximately two million individuals who are assisted by the National Health System from three Local Health Units located in three different regions of Italy.ParticipantsAll patients aged ≥18 years with at least one prescription of simvastatin, ramipril or amlodipine in the period 1 January to 31 December 2010 were included and followed up for 2 years.Main outcome measuresPrescription refills occurring during follow-up were evaluated. Frequency of discontinuation of therapy or substitution with another molecule of the same class (eg, from simvastatin to a different statin) during follow-up was identified.ResultsDuring follow-up, therapy discontinuation or substitution was found to be more frequent in patients switching to a different product of the same active substance compared with non-switching patients (11.5% vs 10.8% and 22.2% vs 20.8% (p=0.002), respectively, in the simvastatin group; 4.0% vs 3.5% and 24.6% vs 22.7% (p<0.001), respectively, in the amlodipine group). In the ramipril group, 8% of patients undertook a therapy substitution to another molecule; no trend towards a lower percentage of substitution was observed in the non-switching group, while 18% of patients discontinued treatment, with a significant difference in favour of patients not switching. These findings were partially confirmed by multivariate analysis.ConclusionsSwitches among products of the same active substance are quite common in patients with cardiovascular disease. Our study suggests that switching may expose patients to a higher risk of therapy discontinuation or substitution.

Real-world Evidence for Adherence and Persistence with Atorvastatin Therapy

“…The literature on outcomes in patients who initiated or switched between branded atorvastatin and its generic version was also sparse; instead, we frequently found studies focusing on therapeutic substitution (switching between different types of statin) [85][86][87][88][89][90][91][92][93][94]. Studies that saw improved adherence with switching therapies highlighted associations with increasing age, prior CVD and polypharmacy, with the authors suggesting that patients who are switched may receive more attention at the pharmacy [95].…”

All-cause mortality, cardiovascular events, and health care costs after 12 months of dual platelet aggregation inhibition after acute myocardial infarction in real-world patients: findings from the Platelet-aggregation Inhibition: Persistence with treatment and cardiovascular Events in Real world (PIPER) study

“…This administrative database is complete and includes validated data, and it has been used in previous real-world studies. 20 , 21 …”