The CredibleMeds^® list: Usage of QT interval prolonging drugs in Germany and discordances with prescribing information

Abstract

The proportion of defined daily doses of CredibleMeds ® drugs among the top 3000 prescribed medicines increased 4.6fold from 2013 (4.6%) to 2019 (20.9%) in Germany, largely due to newly listed drugs in CredibleMeds ® . Major discrepancies between German SmPCs/US Prescribing Information and CredibleMeds ® exist and pose a risk for medication safety.

Development in Prescriptions of Contraindicated and Potentially Harmful QT Interval–Prolonging Drugs in a Large Geriatric Inpatient Cohort From 2011 to 2021

“…Here we have observed, contrary to the decrease for SmPC-QT-drugs and more in line with earlier studies on QT drug-prescribing trends, 41 an increasing prevalence of CredibleMeds-QT-drugs from 2011 to 2021 (2011: 0.4; 2021: 1.8 per patient, Figure 3). The most probable root causes for this positive trend were the continuously growing number of drugs on the CredibleMeds® list, 7 and on the other hand the increasing polypharmacy in general, which we also observed in our geriatric cohort as stated earlier. 32,42 Other contributing factors are likely the increasing age (from 81.0 to 82.3 years) and increasing multimorbidity (from 11.8 to 13.7 diagnoses) in our cohort between 2011 and 2021.…”

“…It could be seen analogously in another study in the German outpatient market, when comparing a defined set of drugs over time, that while "non-QT drugs" were less frequently prescribed, QT drugs remained quite stable. 7 Due to the fact that QT drugs are particularly common among antiarrhythmics, antidepressants, and anti-dementia drugs, 7 it may be difficult to replace them with an equivalent "non-QT drug" alternative.…”

“…There are remaining discrepancies when comparing information about diLQTS in German SmPCs with the international recommended database CredibleMeds®, which we also observed in previous studies on QT warnings in Prescribing Information and SmPCs. 7,14 For example the frequently prescribed drugs donepezil, pantoprazole, or torasemide had no information about QT interactions in the German SmPCs, but were present on the CredibleMeds® list (Figure S2). 6 Despite the remaining discrepancies between the information in German SmPCs and the CredibleMeds® database, the most common co-prescribed substances in particular were quite similar, also in comparison with our 2016 published study.…”

“…6,7 In an analysis of outpatient prescriptions in Germany, we showed that the frequency of drug prescriptions related to CredibleMeds® drugs increased between 2013 and 2019 from 4.6% to 20.9%, which was largely due to an increasing number of drugs listed in CredibleMeds®. 7 One German study estimated the incidence for TdP at 3.3 per million per year among all age groups and 6.9 per million per year in the age group above 65 years. 8 Due to more frequent multimorbidity and polypharmacy, older persons above 65 years represent a particularly vulnerable group that should be more in the focus of drug research.…”

“…A globally recognized collection of QT interval–prolonging drugs (QT drugs) is the database CredibleMeds ® . At the end of 2021 it listed 258 drugs in the categories of known, possible, and conditional TdP risk 6,7 . In an analysis of outpatient prescriptions in Germany, we showed that the frequency of drug prescriptions related to CredibleMeds ® drugs increased between 2013 and 2019 from 4.6% to 20.9%, which was largely due to an increasing number of drugs listed in CredibleMeds ® 7 …”