CJEM Articles: Riyad B. Abu-Laban

Objective: The tolerability of drugs prescribed on emergency department (ED) discharge is unknown. Our objectives were to quantify and describe adverse drug-related events (ADREs) as reported by patients triaged as Canadian Emergency Department Triage and Acuity Scale scores 3, 4 or 5, discharged from the ED with prescriptions.

Methods: This prospective observational study was a planned substudy of a larger study on adherence to discharge prescriptions. This study was conducted in a tertiary care centre with an annual ED census of 69 000 visits. The primary outcome was the frequency of ADREs reported during a structured telephone questionnaire 2 weeks after ED discharge. An ADRE was deemed to have occurred if the patient reported a symptom consistent with a known ADRE that began and resolved within a plausible time frame after starting and stopping the drug, and if no alternative diagnosis was probable.

Results: Research assistants contacted 258/301 (85.7%) patients discharged from the ED with a prescription. An ADRE was reported by 54/258 patients (20.9%, 95% confidence interval [CI] 16.4%-26.3%). The most commonly reported ADREs were nausea, constipation and drowsiness. None required hospital admission or caused death. Participants reporting ADREs were not more likely to make an unplanned ED or clinic revisit (crude odds ratio [OR] 1.1, 95% CI 0.6-2.2; adjusted OR 1.2, 95% CI 0.6-2.4).

Conclusion: Approximately one-fifth of low-acuity patients prescribed medication on discharge from the ED report ADREs, but most of these are neither severe nor associated with an increase in use of health services. Attention to common preventable ADREs, such as opioid-associated constipation, could reduce the rate of ADREs in this population.

Objective: Nonadherence to prescribed medication is associated with increased morbidity and mortality as well as the increased use of health services. The main objective of our study was to assess the incidence of prescription-filling and medication adherence in patients discharged from the emergency department (ED).

Methods: This was a prospective, observational study carried out at a Canadian tertiary care ED with an annual census of 69 000. We enrolled a convenience sample of patients being discharged with a prescription. We queried a provincial prescription-dispensing database 2 weeks later to determine whether prescriptions had been filled. We used a standardized follow-up interview to assess adherence and whether or not the patient experienced an adverse drug-related event (ADRE) or an unplanned revisit to an ED or clinic.

Results: Of the 301 patients who agreed to participate, follow-up was successful for 258 (85.7%). Fifty-one patients (19.8%, 95% confidence interval [CI] 15.4%-25.1%) failed to fill their discharge prescriptions and 104 (40.3%, 95% CI 34.5%-46.4%) did not adhere to 1 or more medications. Antibiotics were associated with a lower odds ratio (OR) of nonadherence (OR 0.21, 95% CI 0.08-0.52). There was a trend toward increasing nonadherence in patients who reported an ADRE (OR 1.84, 95% CI 0.98-3.48) or had 2 or more medications coprescribed (OR 1.71, 95% CI 0.95-3.09). There was also a trend toward a higher risk of a revisit to an ED or clinic in nonadherent patients (OR 1.75, 95% CI 0.94-3.25).

Conclusion: Approximately 4 in 10 patients discharged from the ED did not adhere to his or her prescribed medication. Our results suggest that patients who are prescribed antibiotics are more likely to be adherent, and that further evaluation of the associations between nonadherence, ADREs, the coprescription of 2 or more medications and the use of health services is warranted.

Objective: For many patients with addiction and other substance problems, the emergency department (ED) is the sole provider of medical care. This study sought to determine the prevalence and characteristics of substance-related medical problems in ED patients, as defined by documentation in the medical record. We also sought to compare the ED resource use (length of ED stay and number of revisits) of patients with and without substance problems.

Methods: Trained evaluators using explicit criteria reviewed all ED charts during a 6-week period at a Canadian tertiary care teaching centre. Data was collected on demographics, documentation of problematic substance use and whether the ED visit was due to substance problems. Using a computerized database, we determined how many patients with and without substance problems had 1 or more subsequent ED visits during the 1-year period from Sept. 1, 2002, to Aug. 31, 2003.

Results: Of 6064 visits made by 5194 patients, 6026 visits (99.4%) representing 5188 patients (99.9%) were captured for review. Of those visits, 674 (11.2%, 95% confidence interval [CI] 10.4%-12.0%), made by 600 patients, had documentation of problematic substance use and 521 visits (8.6%, 95% CI 7.9%-9.4%) by 469 patients were caused by substance problems. The mean age of patients with a visit due to a substance problem was 39.2 years, compared with 48.5 years for those with other visits (p < 0.001). The admission rate for substance-related visits was 25.3%, compared with 17.6% for other visits (p < 0.001). For discharged patients, the median length of the ED visit owing to substance-related problems lasted 232 minutes (IQR [interquartile range] 267 min), compared with 164 minutes (IQR 167 min) for other visits (p < 0.001). In 1 year of follow-up, 161 of 600 patients (26.8%) with a substance problem made 466 revisits (mean 0.78 revisits/patient), compared with 975 of 4588 patients (21.3%) without a substance problem who made a total of 2150 revisits (mean 0.47 revisits/patient, p < 0.001).

Conclusion: Substance problems contribute significantly to ED visits, hospital admissions and duration of ED stay at a tertiary centre. It is likely that our methodology underestimates the scope of the problem and that a universal screening program would find a higher prevalence. The magnitude of this problem supports the need for an interdisciplinary identification and intervention program for ED patients with substance-related issues.