Comparison of adverse drug reactions detected by pharmacy and medical records departments

A systematic review to evaluate the accuracy of electronic adverse drug event detection

OBJECTIVE

Adverse drug events (ADEs), defined as adverse patient outcomes caused by medications, are common and difficult to detect. Electronic detection of ADEs is a promising method to identify ADEs. We performed this systematic review to characterize established electronic detection systems and their accuracy.

METHODS

We identified studies evaluating electronic ADE detection from the MEDLINE and EMBASE databases. We included studies if they contained original data and involved detection of electronic triggers using information systems. We abstracted data regarding rule characteristics including type, accuracy, and rationale.

RESULTS

Forty-eight studies met our inclusion criteria. Twenty-four (50%) studies reported rule accuracy but only 9 (18.8%) utilized a proper gold standard (chart review in all patients). Rule accuracy was variable and often poor (range of sensitivity: 40%-94%; specificity: 1.4%-89.8%; positive predictive value: 0.9%-64%). 5 (10.4%) studies derived or used detection rules that were defined by clinical need or the underlying ADE prevalence. Detection rules in 8 (16.7%) studies detected specific types of ADEs.

CONCLUSION

Several factors led to inaccurate ADE detection algorithms, including immature underlying information systems, non-standard event definitions, and variable methods for detection rule validation. Few ADE detection algorithms considered clinical priorities. To enhance the utility of electronic detection systems, there is a need to systematically address these factors.

Characteristics and quality of adverse drug reaction reports by pharmacists in Norway

PURPOSE

To evaluate the characteristics and quality of adverse drug reaction (ADR) reports submitted by pharmacists, and thereby assess the possible contribution of pharmacists to the spontaneous reporting system for ADRs in Norway.

METHODS

An open, prospective study was conducted where dispensing pharmacists from 39 pharmacies were encouraged to report ADRs over a 3-month period. The submitted ADR reports were compared to reports by physicians from the same time period. All reports were evaluated for selected characteristics, that is distribution of Anatomical Therapeutic Chemical (ATC) classification codes of suspected drugs, distribution of ADRs according to system-organ classes and the quality of the reports.

RESULTS

A total of 118 reports covering 274 ADRs received from the pharmacists were compared to 109 ADR reports with 304 ADRs submitted by physicians. Pharmacists more often reported ADRs related to cardiovascular drugs, alimentary tract and metabolism drugs and respiratory drugs, whereas physicians more frequently reported ADRs related to musculoskeletal drugs and antineoplastic and immunomodulating agents. ADRs reported by pharmacists more frequently described gastrointestinal reactions while physicians reported more ADRs in relation to the cardiovascular and blood system. Whereas 68% of the physicians' reports were classified as serious, only 5% of the pharmacists' reports were serious. More than 50% of the reports submitted by pharmacists concerned ADRs following a generic substitution, in contrast to only 2% of the physicians' reports. The pharmacists' reports were found to be of a lower documentation grade. However, there was no substantial difference in a subjective assessment of the quality of information in the reports submitted by the two categories of health professionals.

CONCLUSIONS

Pharmacists submit valuable ADR reports which provide information complimentary to physicians' reports. This emphasises that pharmacist ADR reporting might constitute an important addition to the spontaneous reporting system.

Anti-infectives-induced adverse drug reactions in hospitalized patients

OBJECTIVES

To assess the rate and seriousness of adverse drug reactions (ADRs) attributable to anti-infective agents in hospitalized patients; to estimate the likelihood of experiencing anti-infectives-induced ADRs at different length of drug usage in the hospital; to compare different classes of anti-infectives in inducing ADRs; to determine the impact of age and sex on anti-infectives-induced ADRs.

DESIGN

Prospective cohort study.

PARTICIPANTS

Patients admitted to the infectious diseases department at a university teaching hospital, on Sunday to Wednesday, over a 9 months period, who received at least one anti-infective agent were eligible to enter the study.

MAIN OUTCOME MEASURES

Any suspected noxious and untoward medical events, including laboratory tests abnormalities following anti-infective therapy.

METHODS

All patients admitted have received at least one anti-infective drug. Anti-infective agents induced ADRs were detected by interviewing patients and daily chart review. The seriousness, causality, and type of reactions were classified based on World Health Organization (WHO) definitions. Chi-square analysis was performed to assess the influence of sex and age on occurring ADRs. Both Kaplan-Meier and life table method were used to estimate the time to occur the ADR in anti-infective users. To compare the estimated risk of ADRs induced by different classes of anti-infectives, odds ratios were estimated. In all classes of anti-infectives, the odds ratio of each class was estimated with regard to anti-tuberculosis agents, which had the highest prevalence of ADRs.

RESULTS

During the study period, 460 patients were entered the study. During the same period, 38 ADRs were recognized of which 20 (42%) were serious. The most recognized ADRs were suspected to be induced by anti-tuberculosis agents (29.8%). However in comparing with anti-tuberculosis agents, anti-fungal agents were associated with the highest ADR rate (odds ratio [OR], 4.21; 95% confidence interval [CI], 1.41-1.256) whereas cephalosporines were associated with the lowest rate, (OR, 0.1; 95%CI, 0.04-0.26). The survival analysis shows that the likelihood of experiencing an ADR was increased at first 14 days of drug therapy. Also Chi-square analysis shows that greater risk of anti-infectives-induced ADRs was observed in women.

CONCLUSION

The rate of ADRs induced by anti-infective agents in this study was 8.2%. This is higher than a standard (5%) which has been reported in other studies. This study also shows that some of the classes of anti-infective agents like anti-fungals need more attention.

Drug-related problems in hospitalised patients

Drug-related problems include medication errors (involving an error in the process of prescribing, dispensing, or administering a drug, whether there are adverse consequences or not) and adverse drug reactions (any response to a drug which is noxious and unintended, and which occurs at doses normally used in humans for prophylaxis, diagnosis or therapy of disease, or for the modification of physiological function). Furthermore, adverse drug events can be defined as an injury--whether or not causally-related to the use of a drug. Drug-related problems are relatively common in hospitalised patients and can result in patient morbidity and mortality, and increased costs. In order to get an overview of studies on drug-related problems in hospitalised patients, with specific attention to the incidence of drug-related problems and their costs, to the possibilities of prevention and to the effect of these interventions, we performed a literature search. Incidences of medication errors reported in studies vary widely. The range of reported incidences of adverse drug reactions is even wider. These wide ranges can be largely explained by the different study methods and definitions used. Problems related to drug therapy may be averted by preventive interventions. Several possibilities for prevention exist, especially for the prevention of medication errors. Prescribing, transcription and interpretation errors can be reduced by using computerised physician order entry. Together with the use of automated dispensing systems and bar-code technology, this will aid in the reduction of both dispensing and administration errors. Education of nursing staff involved in the process of drug distribution is another important measure for preventing medication errors. Finally, the introduction of systems for the early detection of adverse drug reactions may help to reduce problems related to drug therapy. Identifying risk factors that contribute to the development of adverse drug reactions, may aid in the prevention of these reactions.