Patient-centered Pharmacist Care in the Hemodialysis Unit: a quasi-experimental interrupted time series study.

BACKGROUND: Nonadherence to medications by patients requiring hemodialysis (HD) leads to unfavorable clinical outcomes. Limited data exist to demonstrate the effect of incorporating patient-centered interventions using concepts of medication therapy management and motivational interview by pharmacists on pharmacoadherence in patients requiring HD. Therefore, we assessed the impact of patient-centered pharmacist care on pharmacoadherence and its outcomes in patients requiring HD. METHODS: Adult patients who had received outpatient HD for at least 3 months were enrolled. The study was conducted from October 2016 to April 2017. Pharmacists interviewed the patients at month 1, 2, 4 and 6, and the intervention (comprehensive review) occurred at months 3 and 5. The primary outcome was the change in pharmacoadherence as assessed by pre-HD serum phosphate levels and the differences in the number of medications between patient' self-report and medications records at the electronic healthcare records (EHRs). The secondary outcomes included changes in systolic blood pressure (SBP), glycosylated hemoglobin levels, serum low-density lipoprotein (LDL) levels, and the prevalence and types of medication-related problems (MRPs). RESULTS: Seventy-two patients were enrolled. Their median age was 59 (interquartile range: 47-67.5) years, and 53% were men. Pre- and post-intervention pharmacoadherence, as indicated by serum phosphate levels and the differences in the number of medications between patient' self-report and the medication records at the EHRs, did not significantly differ (p = 0.682 and 0.348, respectively). Mean SBP and mean LDL did not significantly change post-intervention. The median number of MRPs declined between Months 3 and 5 (p = 0.002): the prevalence of MRPs at Month 3 was 44.9% (95 confidence interval [CI]: 40.4-49.3) and decreased to 29.8% (95 CI: 25.6-34.3) at Month 5. Drug use without indication was the most frequent MRP (23.9%). CONCLUSIONS: Patient-centered pharmacist care did not result in significant changes in pharmacoadherence. However, its clinical utility as a tool to identify and mitigate MRPs in patients requiring HD is indisputable. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03576404 (retrospectively registered on July 3rd, 2018).

Deaths reported from the accidental intrathecal administration of bortezomib.

Medication errors due to the inadvertent intrathecal administration of vincristine and other antineoplastic agents continue to occur despite the development of preventative strategies. Three fatalities due to bortezomib being accidentally given intrathecally instead of by the intended intravenous route have recently been reported by the European Medicines Agency. The most effective method for preventing accidental intrathecal administration is to eliminate the syringe as a means of administrating neurotoxic agents and prepare them in a small volume minibag. However due to a lack of stability data for bortezomib in a minibag and the increasing use of bortezomib via the subcutaneous route necessitates the continued preparation of bortezomib in a syringe. A number of recommendations aimed at preventing the possibility of accidental intrathecal administration of bortezomib are made. These need to be incorporated into standard practice internationally and pharmacists must take the lead to ensure this occurs as a matter of urgency.

Impact of implementing alerts about medication black-box warnings in electronic health records.

BACKGROUND: The Food and Drug Administration issues black-box warnings (BBWs) regarding medications with serious risks, yet physician adherence to the warnings is low. METHODS: We evaluated the impact of delivering BBW-based alerts about drug-drug, drug-disease, and drug-laboratory interactions for prescription medications in outpatients in an electronic health record with clinical decision support. We compared the frequency of non-adherence to all BBWs about drug-drug, drug-disease, and drug-laboratory interactions for 30 drugs/drug classes, and by individual drugs/drug groups with BBWs between the pre- and post-intervention periods. We used multivariate analysis to identify independent risk factors for non-adherence to BBWs. RESULTS: There was a slightly higher frequency of non-adherence to BBWs after the intervention (4.8% vs. 5.1%, p=0.045). In multivariate analyses, after adjustment for patient and provider characteristics and site of care, medications prescribed during the pre-intervention period were less likely to violate BBWs compared to those prescribed during the post-intervention period (OR 0.67, 95% CI, 0.47-0.96). However, black-box warning violations did decrease after the intervention for BBWs about drug-drug interactions (6.1% vs. 1.8%, p<0.0001) and drug-pregnancy interactions (5.1% vs. 3.6%, p=0.01). CONCLUSIONS: Ambulatory care computerized order entry with prescribing alerts about BBWs did not improve clinicians' overall adherence to BBWs, though it did improve adherence for specific clinically important subcategories.

Tiering drug-drug interaction alerts by severity increases compliance rates.

OBJECTIVE: Few data exist measuring the effect of differentiating drug-drug interaction (DDI) alerts in computerized provider order entry systems (CPOE) by level of severity ("tiering"). We sought to determine if rates of provider compliance with DDI alerts in the inpatient setting differed when a tiered presentation was implemented. DESIGN: We performed a retrospective analysis of alert log data on hospitalized patients at two academic medical centers during the period from 2/1/2004 through 2/1/2005. Both inpatient CPOE systems used the same DDI checking service, but one displayed alerts differentially by severity level (tiered presentation, including hard stops for the most severe alerts) while the other did not. Participants were adult inpatients who generated a DDI alert, and providers who wrote the orders. Alerts were presented during the order entry process, providing the clinician with the opportunity to change the patient's medication orders to avoid the interaction. MEASUREMENTS: Rate of compliance to alerts at a tiered site compared to a non-tiered site. RESULTS: We reviewed 71,350 alerts, of which 39,474 occurred at the non-tiered site and 31,876 at the tiered site. Compliance with DDI alerts was significantly higher at the site with tiered DDI alerts compared to the non-tiered site (29% vs. 10%, p < 0.001). At the tiered site, 100% of the most severe alerts were accepted, vs. only 34% at the non-tiered site; moderately severe alerts were also more likely to be accepted at the tiered site (29% vs. 10%). CONCLUSION: Tiered alerting by severity was associated with higher compliance rates of DDI alerts in the inpatient setting, and lack of tiering was associated with a high override rate of more severe alerts.

Rating recommendations for consumers about patient safety: sense, common sense, or nonsense?

BACKGROUND: Although many organizations offer advice about the consumer's role in improving patient safety, little is known about these recommendations. METHODS: The Internet and medical literature were searched to identify patient safety recommendations for consumers. Recommendations were classified by type and tabulated by frequency. Nine investigators rated each recommendation for the quality of supporting empirical evidence, magnitude of benefit, and likely patient adherence. For a consumer perspective, 22 relatives of the investigators who were also mothers rated each recommendation. RESULTS: Twenty-six organizations identified 160 distinct recommendations; 115 (72%) addressed medication safety, 37 (23%) advised patients about preparation for hospitalization or surgery, and 18 (11%) offered general advice. Organizations most frequently advised patients to make a list of their medications (92% of organizations), to ask questions about their health and treatment (81%), to enlist an advocate (77%), and to learn about possible medication side effects (77%). Investigators assigned high scores to 11 of the 25 most frequently cited recommendations and to 4 of the 25 least common recommendations. There was little association between the frequency with which recommendations were promulgated and investigators' ratings (r = 0.27, p < .001). Investigators' scores correlated with those of the mothers (r = 0.71, p < .001). DISCUSSION: Contrary to expectation, there was little overlap among the 160 recommendations offered by the 26 organizations. Health care organizations offer many patient safety recommendations of limited value. These organizations should offer a concise and coherent set of recommendations on the basis of evidence, magnitude of benefit, and likely adherence.

A randomized trial of electronic clinical reminders to improve medication laboratory monitoring.

OBJECTIVE: Recommendations for routine laboratory monitoring to reduce the risk of adverse medication events are not consistently followed. We evaluated the impact of electronic reminders delivered to primary care physicians on rates of appropriate routine medication laboratory monitoring. DESIGN: We enrolled 303 primary care physicians caring for 1,922 patients across 20 ambulatory clinics that had at least one overdue routine laboratory test for a given medication between January and June 2004. Clinics were randomized so that physicians received either usual care or electronic reminders at the time of office visits focused on potassium, creatinine, liver function, thyroid function, and therapeutic drug levels. MEASUREMENTS: Primary outcomes were the receipt of recommended laboratory monitoring within 14 days following an outpatient clinic visit. The effect of the intervention was assessed for each reminder after adjusting for clustering within clinics, as well as patient and provider characteristics. RESULTS: Medication-laboratory monitoring non-compliance ranged from 1.6% (potassium monitoring with potassium-supplement use) to 6.3% (liver function monitoring with HMG CoA Reductase Inhibitor use). Rates of appropriate laboratory monitoring following an outpatient visit ranged from 14% (therapeutic drug levels) to 64% (potassium monitoring with potassium-sparing diuretic use). Reminders for appropriate laboratory monitoring had no impact on rates of receiving appropriate testing for creatinine, potassium, liver function, renal function, or therapeutic drug level monitoring. CONCLUSION: We identified high rates of appropriate laboratory monitoring, and electronic reminders did not significantly improve these monitoring rates. Future studies should focus on settings with lower baseline adherence rates and alternate drug-laboratory combinations.

Adverse drug events in ambulatory care.

BACKGROUND: Adverse events related to drugs occur frequently among inpatients, and many of these events are preventable. However, few data are available on adverse drug events among outpatients. We conducted a study to determine the rates, types, severity, and preventability of such events among outpatients and to identify preventive strategies. METHODS: We performed a prospective cohort study, including a survey of patients and a chart review, at four adult primary care practices in Boston (two hospital-based and two community-based), involving a total of 1202 outpatients who received at least one prescription during a four-week period. Prescriptions were computerized at two of the practices and handwritten at the other two. RESULTS: Of the 661 patients who responded to the survey (response rate, 55 percent), 162 had adverse drug events (25 percent; 95 percent confidence interval, 20 to 29 percent), with a total of 181 events (27 per 100 patients). Twenty-four of the events (13 percent) were serious, 51 (28 percent) were ameliorable, and 20 (11 percent) were preventable. Of the 51 ameliorable events, 32 (63 percent) were attributed to the physician's failure to respond to medication-related symptoms and 19 (37 percent) to the patient's failure to inform the physician of the symptoms. The medication classes most frequently involved in adverse drug events were selective serotonin-reuptake inhibitors (10 percent), beta-blockers (9 percent), angiotensin-converting-enzyme inhibitors (8 percent), and nonsteroidal antiinflammatory agents (8 percent). On multivariate analysis, only the number of medications taken was significantly associated with adverse events. CONCLUSIONS: Adverse events related to drugs are common in primary care, and many are preventable or ameliorable. Monitoring for and acting on symptoms are important. Improving communication between outpatients and providers may help prevent adverse events related to drugs.

Adverse drug event detection in a community hospital utilising computerised medication and laboratory data.

OBJECTIVE: Computerised monitors can detect and, with clinical intervention, often prevent or ameliorate adverse drug events (ADEs). We evaluated whether a computer-based alerting system was useful in a community hospital setting. METHODS: We evaluated 6 months of retrospectively collected medication and laboratory data from a 140-bed community hospital, and applied the rules from a computerised knowledge base to determine if the resulting alerts might have allowed a clinician to prevent or lessen harm related to medication toxicity. We randomly selected 11% (n = 58, of which 56 were available) of charts deemed to be high- or critical-priority alerts, based on the likelihood of the alerts being associated with injury, to determine the frequencies of ADEs and preventable ADEs. RESULTS: In 6 months, there were 8829 activations of the rule set, generating a total of 3547 alerts. Of these, 528 were of high or critical priority, 664 were of medium priority and 2355 were of low priority. Chart review among the sample (56 charts) of high- or critical-priority alerts found five non-preventable and two preventable ADEs, suggesting that among the total high- or critical-priority alerts alone, there would be approximately 94 non-preventable ADEs and 37 preventable ADEs annually in this hospital that could be detected using this method. CONCLUSIONS: Computer-based rules engines have the potential to identify and, with clinical intervention, mitigate preventable ADEs, and implementation is feasible in community hospitals without an advanced information technology application.

Adherence to black box warnings for prescription medications in outpatients.

BACKGROUND: Few data are available regarding the prevalence of potentially dangerous drug-drug, drug-laboratory, and drug-disease interactions among outpatients. Our objectives were to determine how frequently clinicians prescribe drugs in violation of black box warnings for these issues and to determine how frequently such prescribing results in harm. METHODS: In an observational study of 51 outpatient practices using an electronic health record, we measured the frequency with which patients received prescriptions in violation of black box warnings for drug-drug, drug-laboratory, and/or drug-disease interactions. We performed medical record reviews in a sample of patients to detect adverse drug events. Multivariate analysis was conducted to assess the relationship of prescribing in violation of black box warnings to patient and clinician characteristics, adjusting for potential confounders and clustering. RESULTS: Of 324 548 outpatients who received a medication in 2002, 2354 (0.7%) received a prescription in violation of a black box warning. After adjustment, receipt of medication in violation of a black box warning was more likely when patients were 75 years or older or female. The number of medications taken, the number of medical problems, and the site of care were also associated with violations. Less than 1% of patients who received a drug in violation of a black box warning had an adverse drug event as a result. CONCLUSIONS: About 7 in 1000 outpatients received a prescription violating a black box warning. Few incidents resulted in detectable harm.

Improving acceptance of computerized prescribing alerts in ambulatory care.

Computerized drug prescribing alerts can improve patient safety, but are often overridden because of poor specificity and alert overload. Our objective was to improve clinician acceptance of drug alerts by designing a selective set of drug alerts for the ambulatory care setting and minimizing workflow disruptions by designating only critical to high-severity alerts to be interruptive to clinician workflow. The alerts were presented to clinicians using computerized prescribing within an electronic medical record in 31 Boston-area practices. There were 18,115 drug alerts generated during our six-month study period. Of these, 12,933 (71%) were noninterruptive and 5,182 (29%) interruptive. Of the 5,182 interruptive alerts, 67% were accepted. Reasons for overrides varied for each drug alert category and provided potentially useful information for future alert improvement. These data suggest that it is possible to design computerized prescribing decision support with high rates of alert recommendation acceptance by clinicians.

Ability of practitioners to identify solid oral dosage tablets.

PURPOSE: Physicians' and pharmacists' ability to correctly identify three commonly used oral dosage forms was assessed. METHODS: A list of physicians and pharmacists was obtained from two urban teaching hospitals. A total of 100 pharmacists and physicians were randomly selected and their ability to correctly identify three commonly used tablets was tested. Participants were also asked about their experiences and views on current resources and alternatives for identifying oral dosage forms. Tablet-identification exercises were performed by physicians and pharmacists in their usual practice settings. Participants could consult the resources usually available to them for the identification of unknown medications. RESULTS: A total of 300 observations were made in the tablet-identification exercise (100 participants, three tablets per participant). The tablet was correctly identified in 190 of the observations (63%). The brand-name tablet, the generic tablet, and the nonprescription generic tablet were correctly identified in 78%, 64%, and 48% of the observations, respectively. Only 18 physicians (36%) and 24 pharmacists (48%) correctly identified all three tablets, whereas 10 physicians (20%) and 5 pharmacists (10%) could not correctly identify any of the tablets. The mean time required to identify a tablet was 3.65 minutes. Pharmacists most often used electronic resources (52%), while physicians relied on print resources. Overall, 77% expressed dissatisfaction with the current system and 91% favored a universal imprint coding system for oral dosage forms. CONCLUSION: Physicians and pharmacists failed to correctly identify three commonly prescribed tablets more than a third of the time. The brand-name tablet was correctly identified more often than were the prescription generic and nonprescription generic products.

Patient-reported medication symptoms in primary care.

BACKGROUND: Little is known about the prevalence and character of medication-related symptoms in primary care and their relationship to adverse drug events (ADEs) or about factors that affect patient-physician communication regarding medication symptoms. METHODS: The study included 661 patients who received prescriptions from physicians at 4 adult primary care practices. We interviewed patients 2 weeks and 3 months after the index visit, reviewed patients' medical records, and surveyed physicians whose patients identified medication-related symptoms. Physician reviewers determined whether medication symptoms constituted true ADEs. We used multivariable regression to examine factors associated with patients' decision to discuss symptoms with a physician and with physicians' decision to alter therapy. RESULTS: A total of 179 patients identified 286 medication-related symptoms but discussed only 196 (69%) with their physicians. Physicians changed therapy in response to 76% of reported symptoms. Patients' failure to discuss 90 medication symptoms resulted in 19 (21%) ameliorable and 2 (2%) preventable ADEs. Physicians' failure to change therapy in 48 cases resulted in 31 (65%) ameliorable ADEs. In multivariable analyses, patients who took more medications (odds ratio [OR] = 1.06; 95% confidence interval [CI] = 1.04-1.08; P<.001) and had multiple medication allergies (OR = 1.07; 95% CI = 1.03-1.11; P = .001) were more likely to discuss symptoms. Male physicians (OR = 1.20, 95% CI = 1.09-1.26; P = .002) and physicians at 2 practices were more likely to change therapy (OR = 1.24; 95% CI = 1.17-1.28; P<.001; and OR = 1.17; 95% CI = 1.08-1.24; P = .002). CONCLUSION: Primary care physicians may be able to reduce the duration and/or the severity of many ADEs by eliciting and addressing patients' medication symptoms.

Potential savings from substituting generic drugs for brand-name drugs: medical expenditure panel survey, 1997-2000.

BACKGROUND: Generic substitution is one mechanism of curtailing prescription drug expenditures. Limited information is available about the potential savings associated with generic substitution. OBJECTIVE: To estimate the potential savings associated with broad substitution of generic drugs. DESIGN: Cross-sectional, nationally representative survey of noninstitutionalized adults. SETTING: United States. PARTICIPANTS: Adults included in the Medical Expenditure Panel Survey Household Component, 1997-2000. MEASUREMENTS: Use of a multisource drug (that is, a drug available in a brand-name and > or =1 generic formulation) or a generic drug and the potential cost savings associated with broad generic substitution for all multisource products. RESULTS: Fifty-six percent of all outpatient drugs were multisource products, accounting for 41% of total outpatient drug expenditures. Of these multisource drugs, 61% were dispensed as a generic. If a generic had been substituted for all corresponding brand-name outpatient drugs in 2000, the median annual savings in drug expenditures per person would have been 45.89 dollars (interquartile range, 10.35 dollars to 158.06) for adults younger than 65 years of age and 78.05 dollars (interquartile range, 19.94 dollars to 241.72 dollars) for adults at least 65 years of age. In these age groups, the national savings would have been 5.9 billion dollars (95% CI, 5.5 billion dollars to 6.2 billion dollars) and 2.9 billion dollars (CI, 2.6 billion dollars to 3.1 billion dollars), respectively, representing approximately 11% of drug expenditures. LIMITATIONS: Specific information about an individual's formulary was not available, so the authors could not estimate how much of the potential savings would benefit an individual or his or her health plan. CONCLUSION: Although broad substitution of generic drugs would affect only a modest percentage of drug expenditures, it could result in substantial absolute savings.

The vulnerabilities of computerized physician order entry systems: a qualitative study.

OBJECTIVE: To test the vulnerabilities of a wide range of computerized physician order entry (CPOE) systems to different types of medication errors, and develop a more comprehensive qualitative understanding of how their design could be improved. MATERIALS AND METHODS: The authors reviewed a random sample of 63,040 medication error reports from the US Pharmacopeia (USP) MEDMARX reporting system where CPOE systems were considered a "contributing factor" to errors and flagged test scenarios that could be tested in current CPOE systems. Testers entered these orders in 13 commercial and homegrown CPOE systems across 16 different sites in the United States and Canada, using both usual practice and where-needed workarounds. Overarching themes relevant to interface design and usability/workflow issues were identified. RESULTS: CPOE systems often failed to detect and prevent important medication errors. Generation of electronic alert warnings varied widely between systems, and depended on a number of factors, including how the order information was entered. Alerts were often confusing, with unrelated warnings appearing on the same screen as those more relevant to the current erroneous entry. Dangerous drug-drug interaction warnings were displayed only after the order was placed rather than at the time of ordering. Testers illustrated various workarounds that allowed them to enter these erroneous orders. DISCUSSION AND CONCLUSION: The authors found high variability in ordering approaches between different CPOE systems, with major deficiencies identified in some systems. It is important that developers reflect on these findings and build in safeguards to ensure safer prescribing for patients.

Ambulatory Computerized Prescribing and Preventable Adverse Drug Events.

BACKGROUND: Adverse drug events (ADEs) represent a significant cause of injury in the ambulatory care setting. Computerized physician order entry reduces rates of serious medication errors that can lead to ADEs in the inpatient setting, but few studies have evaluated whether computerized prescribing in the ambulatory setting reduces preventable ADE rates in ambulatory care. OBJECTIVE: To determine the rates of preventable ADEs before and after the implementation of computerized prescribing with basic clinical decision support for ordering medications. DESIGN: Before-after study of ADE rates in practices implementing computer order entry. PARTICIPANTS: Adult patients seeking care in primary care practices at academic medical centers in Boston, Massachusetts (n = 41,819), and Indianapolis, Indiana (n = 9128). MAIN MEASURES: We attempted to standardize the medication-related decision support knowledge base provided at the 2 sites, although the electronic records and presentation layers used at the 2 sites differed. The primary outcome was preventable ADEs identified based on structured results or symptoms defined by extracting symptom concepts from provider notes; potential ADEs were a secondary outcome. RESULTS: Computerized prescribing did not significantly change the rate of preventable ADEs at either site. Compared with Boston practices, the rate of potential ADEs was more than seven-fold greater at Indianapolis (6.4/10,000 patient-months vs. 49.5/10,000 patient-months, P < 0.001). Computerized prescribing was associated with a 56% decrease in the potential ADE rate at Indianapolis (49.5 to 21.9/10,000 patient-months, P < 0.001) but a 104% increase at Boston (6.4 to 13.0/10,000 patient-months, P < 0.001). Preventable ADEs that occurred after computerized prescribing was implemented were due to patient education issues, physicians ignoring feedback from CDSS, and incomplete computerized knowledge base was incomplete (34%, 33%, and 33% in Indianapolis and 44%, 28%, and 28% in Boston). CONCLUSIONS: The implementation of computerized prescribing in the ambulatory setting was not associated with any change in preventable ADEs but was associated with a decrease in potential ADEs at Indianapolis but an increase at Boston, although the absolute rate of ADEs was much lower in Boston.

Outpatient prescribing errors and the impact of computerized prescribing.

BACKGROUND: Medication errors are common among inpatients and many are preventable with computerized prescribing. Relatively little is known about outpatient prescribing errors or the impact of computerized prescribing in this setting. OBJECTIVE: To assess the rates, types, and severity of outpatient prescribing errors and understand the potential impact of computerized prescribing. DESIGN: Prospective cohort study in 4 adult primary care practices in Boston using prescription review, patient survey, and chart review to identify medication errors, potential adverse drug events (ADEs) and preventable ADEs. PARTICIPANTS: Outpatients over age 18 who received a prescription from 24 participating physicians. RESULTS: We screened 1879 prescriptions from 1202 patients, and completed 661 surveys (response rate 55%). Of the prescriptions, 143 (7.6%; 95% confidence interval (CI) 6.4% to 8.8%) contained a prescribing error. Three errors led to preventable ADEs and 62 (43%; 3% of all prescriptions) had potential for patient injury (potential ADEs); 1 was potentially life-threatening (2%) and 15 were serious (24%). Errors in frequency (n=77, 54%) and dose (n=26, 18%) were common. The rates of medication errors and potential ADEs were not significantly different at basic computerized prescribing sites (4.3% vs 11.0%, P=.31; 2.6% vs 4.0%, P=.16) compared to handwritten sites. Advanced checks (including dose and frequency checking) could have prevented 95% of potential ADEs. CONCLUSIONS: Prescribing errors occurred in 7.6% of outpatient prescriptions and many could have harmed patients. Basic computerized prescribing systems may not be adequate to reduce errors. More advanced systems with dose and frequency checking are likely needed to prevent potentially harmful errors.

Risk factors for adverse drug events among older adults in the ambulatory setting.

OBJECTIVES: To gather information on patient-level factors associated with risk of adverse drug events (ADEs) that may allow focus of prevention efforts on patients at high risk. DESIGN: Nested case-control study. SETTING: Large multispecialty group practice in New England. PARTICIPANTS: All Medicare enrollees cared for by a multispecialty group practice during 1 year (N=30,397 person-years from July 1, 1999, through June 30, 2000). For each patient with an ADE, a control was randomly selected. MEASUREMENTS: Data were abstracted from medical records on age, sex, comorbidities, and medication use at the time of the event. RESULTS: ADEs were identified in 1,299 older adults. Independent risk factors included being female and aged 80 and older. There were dose-response associations with the Charlson Comorbidity Index and number of scheduled medications. Patients taking anticoagulants, antidepressants, antibiotics, cardiovascular drugs, diuretics, hormones, and corticosteroids were at increased risk. In the analysis of preventable ADEs, the dose-response relationship with comorbidity and number of medications remained. Patients taking nonopioid analgesics (predominantly nonsteroidal antiinflammatory drugs and acetaminophen), anticoagulants, diuretics, and anti-seizure medications were at increased risk. CONCLUSION: Prevention efforts to reduce ADEs should be targeted toward older adults with multiple medical conditions or taking multiple medications, nonopioid analgesics, anticoagulants, diuretics, and antiseizure medications.

Strategies for detecting adverse drug events among older persons in the ambulatory setting.

OBJECTIVE: To examine various strategies for the identification of adverse drug events (ADEs) among older persons in the ambulatory clinical setting. DESIGN: A cohort study of Medicare enrollees (n = 31,757 per month) receiving medical care from a large multispecialty group practice during a 12-month observation period (July 1, 1999 through June 30, 2000). MEASUREMENTS: Possible drug-related incidents occurring in the ambulatory clinical setting were detected using signals from multiple sources. RESULTS: During the tracking period, there were 1,523 identified ADEs, of which 421 (28%) were considered preventable. Across all sources, 23,917 signals were found; 12,791 (53%) were potential incidents that led to review of a patient's medical record and 2,266 (9%) were presented to physician reviewers. Although the positive predictive value (PPV) for reports from providers was high compared with other sources (54%), only 11% of the ADEs and 6% of the preventable ADEs were identified through this source. PPVs for other sources ranged from a low of 4% for administrative incident reports to a high of 12% for free-text review of electronic notes. Computer-generated signals were the source for 31% of the ADEs and 37% of the preventable ADEs. Electronic notes were the source for 39% of the ADEs and 29% of the preventable ADEs. There was little overlap in the ADEs identified across all sources. CONCLUSION: Our findings emphasize the limitations of voluntary reporting by health care providers as the principal means for detection of ADEs and suggest that multiple strategies are required to detect ADEs in geriatric ambulatory patients.

An evaluation of risk factors for adverse drug events associated with angiotensin-converting enzyme inhibitors.

RATIONALE, AIMS AND OBJECTIVES: To identify potential factors leading to discontinuation of angiotensin-converting enzyme (ACE) inhibitors because of adverse drug events. METHODS: Retrospective cohort study was conducted at outpatient clinics affiliated with an urban tertiary care hospital. ACE inhibitors were administered to 2225 consecutive outpatients. RESULTS: In 19% of the total cohort, ACE inhibitors were discontinued because of adverse drug events. Cox proportional hazard model identified the following independent risk factors for discontinuation because of adverse drug events: age, female gender, ethnicity other than African American or Latino, no history of previous ACE inhibitor use, history of cough caused by another ACE inhibitor, hypertension, anxiety or depression, no hemodialysis, and elevated creatinine. History of smoking was shown to be a risk factor for cough [hazard ratio (HR): 2.5; 95% confidence interval (CI): 1.1-5.7], angioedema (HR: 2.7; 95% CI: 1.1-7.0), and hyperkalaemia (HR: 5.4; 95% CI: 1.3-23.2). History of ACE inhibitor-induced cough was not only a risk factor for cough (HR: 12.9; 95% CI: 7.5-22.3) but also for angioedema (HR: 9.1; 95% CI: 2.1-39.9). Patients with creatinine > or = 1.6 mg dL(-1) were likely to discontinue ACE inhibitors because of renal dysfunction (HR: 4.7; 95% CI: 1.5-12.7) and hyperkalaemia (HR: 10.9; 95% CI: 3.1-39.0). East Asians were more likely to develop cough (HR: 2.5; 95% CI: 1.1-5.7) and hyperkalaemia (HR: 80.3; 95% CI: 5.4-1190) and African Americans to develop angioedema (HR: 3.5; 95% CI: 1.3-8.9). CONCLUSIONS: Although further validation is necessary, these risk factors should help doctors identify patients with elevated risk for adverse drug events because of ACE inhibitors.