CLINICAL PHARIVlACOLOGY & THEIULPEUT1CS P 9 6 American Society for Clinical Pharmacology and Therapeutics FEBRUARY2003

PDII-B-5 DIFFERENCES IN QTC INTERVAL BETWEEN MALE AND

FEMALE SUBJECTS PRESCRIBED THE CLASS Iii ANTIAR- RHYTHMIC DRUG AMIODARONE. S. H. Thomas, MD, H. E1 Eraky, PhD, University of Newcastle, Newcastle, United Kingdom (Great Britain).

There is evidence that women are at higher risk than men of torsade de pointes ventricular tachycardia when exposed to drugs that delay cardiac repolarisation. Quinidine-induced QT prolongation is also more marked in women. In this cross sectional study, sex differences in plasma drug concentrations and QT intervals were investigated in patients taking amiudarone.

Compared with males (n = 29), females (n = 12) were prescribed a similar weight-adjusted amiodarone dose and had similar plasma concentrations of amiodarone and desethylamiodarone. There were no significant differences in hepatic or renal function or in plasma electrolytes, calcium or magnesium. Bazett-corrected QTc interval was longer in females than males (mean ± S.D: 472 _+ 14 vs. 432 ± 24 ms, P < 0.0001) and the mean difference (41 ± 28, 95% CI 32, 49 ms) was larger than that observed in 160 unmedicated healthy volunteers (12 ± 27, 95% CI 8, 16 ms, P < 0.001). When an ECG was available for analysis prior to amiodarone therapy (18 males, 7 females), the change associated with amiodarone was larger in fe- males than in males (30 -+ 23 vs 3 ± 41 ms, P < 0.05).

These results suggest that women are more sensitive to the QT prolonging effect of amiodarone. This effect is not caused by differ- ences in plasma drug concentration.

PDII-B-7 USE OF ELECTRONIC MEDICAL RECORDS TO DETECT

ADVERSE DRUG EVENTS AND MEDICATION ERRORS IN OUTPATIENTS. C. J. Hope, PharmD~ A. C. Seger, RPh, J. M. Overhage, MD, PhD, T. K. Gandhi, MD, MPH, E. Y. Teal, MA, V. L. Mills, LPN, D. W. Bates, MD, MSc, M. D. Murray, PharmD, MPH, Regenstrief Institute/Purdue, Brigham & Women's Hospital, Regen- strief/IU, Regenstrief/Purdue, Indianapolis, IN.

Purpose: Adverse drug events (ADEs) ranging from mild to severe are common among outpatients. Our purpose was to determine the frequency of ADEs and medication errors (MEs) in a large ambulatory practice. With this knowledge future efforts can be con- centrated in those areas with the highest expected yield of events.

Methods: We searched visit notes, diagnoses, pharmacy records and laboratory results in four months of electronic records. Records that met one of 130 criteria defined by an expert panel were identified as "signals" and were subsequently adjudicated by an interdiscipli- nary team.

Results: Among 38,376 total office visits screened, we found 690 ADEs and 414 MEs. Signals had positive predictive values for ADEs and MEs of 12% and 7%, respectively. One third of the signals identified 73% of the ADEs as shown in Table 1. The top five MEs were drug monitoring (64%), drug and age (17%), drug interactions (5%), duplicate therapy (5%), and glucose monitoring (4%). Analysis of 21% of the signals identified 95% of the MEs.

Table 1: Top Five Signals Groups for ADEs

Signal Group % of ADEs % of Signals

Screening by Labs 27.5% 8.7% Abnormal Potassium 12.3% 11.0% Hepatotoxieity 11.6% 6.6% Renal Insufficiency 10.8% 3.0% Drug & Tests/Procedures 10.6% 3.8% Sum 72.8% 33.1%

Conclusion: Computer screening of electronic records is a valu- able tool for the detection of outpatient ADEs and MEs. A core group of signals detected a large proportion of ADEs and MEs.

PDII-B-6 PDII-C-1

ABSTRACT WITHDRAWN. ABSTRACT REASSIGNED TO PIII-59.