Adverse events occurred frequently in the peridischarge period, and many could potentially have been prevented or ameliorated with simple strategies.

OBJECTIVE:To describe the incidence of adverse drug events (ADEs), preventable ADEs, and ameliorable ADEs occurring after hospital discharge and their associated risk factors.DESIGN: Prospective cohort study.SETTING: Urban academic health sciences center.PATIENTS: Consecutive patients discharged home from the general medical service. INTERVENTIONS:We determined posthospital outcomes approximately 24 days following discharge by performing a chart review and telephone interview. Using the telephone interview, we identified new or worsening symptoms, the patient's health system use, and recollection of processes of care. Posthospital outcomes were judged by 2 internists independently.RESULTS: Four hundred of 581 potentially eligible patients were evaluated. Of the 400 patients, 45 developed an ADE (incidence, 11%; 95% confidence interval [CI], 8% to 14%). Of these, 27% were preventable and 33% were ameliorable. Injuries were significant in 32 patients, serious in 6, and life threatening in 7. Patients were less likely to experience an ADE if they recalled having side effects of prescribed medications explained (OR, 0.4; 95% CI, 0.2 to 0.8). The risk of ADE per prescription was highest for corticosteroids, anticoagulants, antibiotics, analgesics, and cardiovascular medications. Risk increased with prescription number. Failure to monitor was an especially common cause of preventable and ameliorable ADEs. CONCLUSION:Following discharge, ADEs were common and many were preventable or ameliorable. Medication side effects should be discussed, and interventions should include better monitoring and target patients receiving specific drug classes or multiple medications.

Among patients undergoing inpatient surgical procedures at VA medical centers, natural language processing analysis of electronic medical records to identify postoperative complications had higher sensitivity and lower specificity compared with patient safety indicators based on discharge coding.

Computerized detection of adverse events will soon be practical on a widespread basis.

Promoting patient safety is a national priority. To evaluate interventions for reducing medical errors and adverse event, effective methods for detecting such events are required. This paper reviews the current methodologies for detection of adverse events and discusses their relative advantages and limitations. It also presents a cognitive framework for error monitoring and detection. While manual chart review has been considered the "gold-standard" for identifying adverse events in many patient safety studies, this methodology is expensive and imperfect. Investigators have developed or are currently evaluating, several electronic methods that can detect adverse events using coded data, free-text clinical narratives, or a combination of techniques. Advances in these systems will greatly facilitate our ability to monitor adverse events and promote patient safety research. But these systems will perform optimally only if we improve our understanding of the fundamental nature of errors and the ways in which the human mind can naturally, but erroneously, contribute to the problems that we observe.

Background The comparative effectiveness of sulfonylureas and metformin on cardiovascular disease (CVD) outcomes in type 2 diabetes are not well characterized. Objective To compare the effectiveness of sulfonylureas and metformin on the outcome of CVD (acute myocardial infarction, stroke) or death Design Retrospective cohort study Setting National Veterans Health Administration (VHA) databases linked to Medicare files Patients Veterans who initiated metformin or sulfonylureas for diabetes. Patients with chronic kidney disease or serious medical illness were excluded. Measurements Composite outcome of hospitalizations for acute myocardial infarction, stroke, or death. Cox regression analyses compared the incidence of the composite outcome between groups, adjusting for baseline demographics, medications, cholesterol, glycated hemoglobin, creatinine, blood pressure, body mass index, healthcare utilization and co-morbidities. Results Among 253,690 patients (98,665 sulfonylurea and 155,025 metformin initiators) the crude outcome rates were 18.2 and 10.4 per 1000 person-years in sulfonylurea and metformin users, respectively (adjusted hazard ratio [aHR] 1.21, 95% Confidence Intervals [CI] 1.13, 1.30). Results were consistent for both glyburide (aHR 1.26, 95% CI 1.16, 1.37) and glipizide (aHR 1.15, 95% CI 1.06, 1.26) as well as for those with prior history of CVD (aHR 1.25, 95% CI 1.13, 1.55) and without history of CVD (aHR: 1.16, 95% CI: 1.06, 1.29). Results were also consistent in a propensity score-matched analysis. For patients initiating sulfonylureas rather than metformin, we estimated an excess of 1 and 4 CVD events per 1000 person-years for those without and with a CVD history, respectively. Limitations Data on women and minorities is limited but reflective of the VHA population. Conclusions Use of sulfonylureas compared to metformin for initial treatment of diabetes was associated with an increased hazard of CVD events or death.

Hospitals that operate at or over capacity may experience heightened rates of patient safety events and might consider re-engineering the structures of care to respond better during periods of high stress.

Importance Preferred second line medication for diabetes treatment after metformin failure remains uncertain. Objective We compared time to acute myocardial infarction [AMI], stroke, or death in a cohort of metformin initiators who added insulin or a sulfonylurea. Design Retrospective cohort constructed using national Veterans Health Administration, Medicare, and National Death Index databases. Participants Veterans initially treated with metformin from 2001 through 2008 who subsequently added either insulin or sulfonylurea. Each insulin intensifier was propensity score matched by characteristics to five sulfonylurea intensifiers. Patients were followed through September, 2011 for primary analyses or September, 2009 for cause of death analyses. Main Outcome Measures Risk of a composite outcome of AMI, stroke hospitalization or all-cause death was compared between therapies using marginal structural Cox proportional hazard models to adjust for baseline and time-varying demographics, medications, cholesterol, hemoglobin A1c, creatinine, blood pressure, body mass index, and co-morbidities. Results Among 178,341 metformin monotherapy patients, 2,948 and 39,990 added insulin or sulfonylurea, respectively. Propensity score matching yielded 2,436 metformin+insulin and 12,180 metformin+sulfonylurea patients. At intensification, the median (interquartile range) time on metformin was 14 months (5, 30) and HbA1c was 8.1% (7.2, 9.9). There were 172 versus 634 events for the primary outcome among those who added insulin versus sulfonylureas respectively (42 versus 33 events per 1000 person-years, adjusted hazard ratio [aHR] 1.30, 95% confidence interval [CI] 1.07, 1.58, p=0.009). AMI and stroke rates were statistically similar 41 versus 229 (10.2 and 11.9 per 1000 person years, aHR 0.88,95% CI 0.59, 1.30, p=0.52), while all-cause death rates were137 versus 444, respectively (33.7 and 22.7 per 1000 person-years, aHR 1.44, 95% CI,1.15, 1.79, p=0.001). There were 54 versus 258 secondary outcomes: AMI, stroke hospitalizations or cardiovascular deaths (22.8 vs. 22.5 events per 1000 person years aHR 0.98, 95% CI 0.71, 1.34. p=0.87). Conclusions Among patients with diabetes using metformin, the addition of insulin versus sulfonylurea was associated with an increased risk of a composite of nonfatal cardiovascular outcomes and all-cause mortality. These findings require further investigation to understand risks associated with insulin use in these patients.