Successful strategy to improve the specificity of electronic statin-drug interaction alerts.
OBJECTIVE
A considerable weakness of current clinical decision support systems managing drug-drug interactions (DDI) is the high incidence of inappropriate alerts. Because DDI-induced, dose-dependent adverse events can be prevented by dosage adjustment, corresponding DDI alerts should only be issued if dosages exceed safe limits. We have designed a logical framework for a DDI alert-system that considers prescribed dosage and retrospectively evaluates the impact on the frequency of statin-drug interaction alerts.


METHODS
Upper statin dose limits were extracted from the drug label (SPC) (20 statin-drug combinations) or clinical trials specifying the extent of the pharmacokinetic interaction (43 statin-drug combinations). We retrospectively assessed electronic DDI alerts and compared the number of standard alerts to alerts that took dosage into account.


RESULTS
From among 2457 electronic prescriptions, we identified 73 high-risk statin-drug pairs. Of these, SPC dosage information classified 19 warnings as inappropriate. Data from pharmacokinetic trials took quantitative dosage information more often into consideration and classified 40 warnings as inappropriate. This is a significant reduction in the number of alerts by 55% compared to SPC-based information (26%; p < 0.001).


CONCLUSIONS
This retrospective study of pharmacokinetic statin interactions demonstrates that more than half of the DDI alerts that presented in a clinical decision support system were inappropriate if DDI-specific upper dose limits are not considered.
Seidling
Hanna Marita
HM
Department of Internal Medicine VI, Clinical Pharmacology and Pharmacoepidemiology, University of Heidelberg, Heidelberg, Germany.
Storch
Caroline Henrike
CH
Bertsche
Thilo
T
Senger
Christian
C
Kaltschmidt
Jens
J
Walter-Sack
Ingeborg
I
Haefeli
Walter Emil
WE
D020000:Decision Support Systems, Clinical; D004347:Drug Interactions; D004359:Drug Therapy, Combination / Q000009:adverse effects; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000008:administration & dosage* / Q000009:adverse effects / Q000493:pharmacokinetics; D050316:Medical Order Entry Systems; D008508:Medication Errors / Q000517:prevention & control; D012189:Retrospective Studies
D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors