Drugs inducing QTcP
To categorise potential drugs induced QTcP, we adopted the most updated
CredibleMeds© (May 18, 2020), and then we subdivided
these medications into the following categories (18): 1) known risky
category which includes all medications with proven evidences of causing
QTcP, and are associated with a potential causing of TdP, 2) possible
risky group which encompasses all drugs with significant evidences of
causing QTcP, but with insignificant evidences that these medications
have a risk of causing TdP, and 3) conditional risk group which includes
all medicines with sufficient evidences that confirm possible causing
QTcP, and TdP, but only under certain circumstances (e.g. inappropriate
dosage, or being in a drug–drug interaction). Minor polypharmacy
prescriptions were assumed to contain 2-4 prescribed drugs, and major
polypharmacy prescriptions were defined to have ≥ 5 prescribed drugs
(30).