CMAJ open最新文献

Background: Ranitidine was the most prescribed histamine-2 receptor antagonist (H₂RA) in Canada when recalled in 2019 because of potential carcinogenicity. We sought to compare geographic and temporal patterns in use of prescription ranitidine and 3 other HRAs and estimated population exposure to ranitidine in 6 provinces between 1996 and 2019.

Methods: This population-based serial cross-sectional study used prescription claims for H₂RAs dispensed from community pharmacies in Nova Scotia, Ontario, Manitoba, Saskatchewan, Alberta and British Columbia. We estimated the period prevalence of ranitidine use per 100 population by province, age category and sex. We estimated exposure to ranitidine between 2015 and 2019 using defined daily doses (DDDs).

Results: Overall, 2.4 million ranitidine prescriptions were dispensed to patients aged 65 years and older, and 1.7 million were dispensed to younger adults. Among older adults, the median period prevalence of ranitidine use among females was 16% (interquartile range [IQR] 13%-27%) higher than among males. Among younger adults, the median prevalence was 50% (IQR 37%-70%) higher among females. Among older adults, between 1996 and 1999, use was highest in Nova Scotia (33%) and Ontario (30%), lower in the prairies (Manitoba [18%], Saskatchewan [26%], Alberta [17%]) and lowest in BC (11%). By 2015-2019, use of ranitidine among older adults dropped by at least 50% in all provinces except BC. We estimate that at least 142 million DDDs of prescribed ranitidine were consumed annually in 6 provinces (2015-2019).

Interpretation: Over the 24-year period in 6 provinces, patients aged 65 years and older were dispensed 2.4 million prescriptions of ranitidine and younger adults were dispensed 1.7 million prescriptions of ranitidine. These estimates of ranitidine exposure can be used for planning studies of cancer risk and identifying target populations for cancer surveillance.

Background: Identifying people with Lynch syndrome, a genetic condition predisposing those affected to colorectal, endometrial and other cancers, allows for implementation of risk-reducing strategies for patients and their families. The goal of this study was to describe screening and testing practices for this condition among people with endometrial cancer in Nova Scotia, Canada, and to determine the prevalence of Lynch syndrome in this population.

Methods: All patients diagnosed with endometrial cancer in Nova Scotia between May 1, 2017, and Apr. 30, 2020 were identified through a provincial gynecologic oncology database. Patients from out of province were excluded. We collected age, body mass index, tumour mismatch repair protein immunohistochemistry results, personal and family histories, and germline testing information for all patients.

Results: We identified 465 people diagosed with endometrial cancer during the study period. Most were aged 51 years or older, and had obesity and low-grade early-stage endometrioid tumours. Tumour immunohistochemistry testing was performed in 444 cases (95.5%). Based on local criteria, 189 patients were eligible for genetic counselling, of whom 156 (82.5%) were referred to medical genetics. Of the 98 patients who underwent germline testing, 9 (9.2%) were diagnosed with Lynch syndrome.

Interpretation: The prevalence of Lynch syndrome was at least 1.9% (9/465) in this population. Our results illustrate successful implementation of universal tumour testing; however, there remains a gap in access to genetic counselling.

Background: Patient death is an inevitability during medical training, with subsequent psychologic distress, decreased empathy and worse learning outcomes. We aimed to explore resident experiences with patient death early in training, including the immediate and delayed impacts of these experiences, preparedness of trainees for these events and coping strategies used, potentially identifying gaps and opportunities to further support trainees during difficult or traumatic events.

Methods: We performed a qualitative study using phenomenology methodology to understand trainees' personal experiences with patient death. Resident physicians who had completed an internal medicine rotation at McMaster University, Hamilton, Ontario, were invited to participate from December 2020 to April 2021. Semistructured interviews were conducted to understand circumstances, emotional responses, support, coping mechanisms and preparedness regarding the patient death experience. Interviews were transcribed and coded to identify emerging themes with the use of thematic and interpretive analysis.

Results: Eighteen participants were interviewed. On average, the interviews were 40 minutes in length. The participants' mean age was 27 years. The majority of trainees (10 [56%]) were in their first year of residency, with 5 (28%) from family medicine and 4 (22%) from internal medicine. Most participants (13 [72%]) had experienced their first patient death during medical school. Three themes were identified: patient death circumstances, immediate and delayed emotional impact, and preparedness and coping mechanisms. Unexpected death, pronouncing death, cardiopulmonary resuscitation and communicating with families were common challenges. Feelings of guilt, helplessness and grief followed the events. Feeling underprepared contributed to emotional consequences, including difficulties sleeping, intrusive thoughts and emotional distancing; however, these experiences were consistently normalized by participants.

Interpretation: Patient death during medical training can be traumatic for trainees and may perpetuate loss of empathy, changes to practice and residual emotional effects. Educational initiatives to prepare trainees for patient death and teach adaptive coping strategies may help mitigate psychologic trauma and loss of empathy; further research is required to explore these strategies.

Background: Most antibiotics dispensed by community pharmacies in Canada are prescribed by family physicians, but using the prescribing information contained within primary care electronic medical records (EMRs) for secondary purposes can be challenging owing to variable data quality. We used antibiotic medications as an exemplar to validate a machine-learning approach for cleaning and coding medication data in a pan-Canadian primary care EMR database.

Methods: The Canadian Primary Care Sentinel Surveillance Network database contained an estimated 42 million medication records, which we mapped to an Anatomic Therapeutic Chemical (ATC) code by applying a semisupervised classification model developed using reference standard labels derived from the Health Canada Drug Product Database. We validated the resulting ATC codes in a subset of antibiotic records (16 119 unique strings) to determine whether the algorithm correctly classified the medication according to manual review of the original medication record.

Results: In the antibiotic subset, the algorithm showed high validity (sensitivity 99.5%, specificity 92.4%, positive predictive value 98.6%, negative predictive value 97.0%) in classifying whether the medication was an antibiotic.

Interpretation: Our machine-learning algorithm classified unstructured antibiotic medication data from primary care with a high degree of accuracy. Access to cleaned EMR data can support important secondary uses, including community-based antibiotic prescribing surveillance and practice improvement.

Background: In 2020, International Statistical Classification of Diseases and Related Health Problems, 10th Revision (ICD-10) codes were created for laboratory-confirmed SARS-CoV-2 infections. We assessed the operating characteristics of ICD-10 discharge diagnostic code U07.1 within the General Medicine Inpatient Initiative (GEMINI).

Methods: GEMINI assembles hospitalization data (including administrative ICD-10 discharge diagnostic codes, laboratory results and demographic data) from hospitals in Ontario, Canada. We studied adults (age ≥ 18 yr) admitted during 2020 and tested at least once for SARS-CoV-2 via polymerase chain reaction (PCR) during (or within 48 h before) hospitalization. With PCR results as the reference standard, we calculated sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for ICD-10 code U07.1 hospital discharge diagnostic codes. Analyses were stratified by demographic data, calendar period and timing of the first test (within or after 48 h of hospital admission).

Results: In 11 852 hospitalizations with at least 1 SARS-CoV-2 PCR test, 444 (3.7%) were positive. The sensitivity of code U07.1 to identify SARS-CoV-2 infection was 97.8%, specificity was 99.5%, PPV was 88.2% and NPV was 99.9%. Operating characteristics were similar in most stratified analyses, but the specificity and PPV were lower if the first SARS-CoV-2 test was done more than 48 hours after admission.

Interpretation: The sensitivity, specificity, PPV and NPV of code U07.1 were high. This supports using code U07.1 to identify SARS-CoV-2 infection in hospitalization data.

Background: Avoidance of care during the pandemic may have contributed to delays in care, and as a result, worse patient outcomes. We evaluated markers of illness acuity on presentation to the emergency department among patients with non-COVID-19-related emergent diagnoses and associated outcomes.

Methods: We conducted a retrospective study using linked administrative data from Ontario. We selected 4 emergent diagnoses, namely appendicitis, ectopic pregnancy, renal failure and diabetic ketoacidosis. We used the nonemergent diagnosis of cellulitis as a control. Our primary outcome of interest was hospital admission. Secondary outcomes were ambulance arrival, surgical intervention, subsequent hospital admission within 30 days of discharge from the emergency department or hospital and 30-day mortality. We compared outcomes during the first year of the COVID-19 pandemic (Mar. 15-Dec. 31, 2020) with a control period (Mar. 15-Dec. 31, 2018, and Mar. 15-Dec. 31, 2019).

Results: Emergency department visits for all conditions initially decreased during the pandemic. During this period, patients across all study diagnoses were more likely to arrive to the emergency department via ambulance. Patients with an ectopic pregnancy had higher odds of surgery in the pandemic period (odds ratio [OR] 1.27, 95% confidence interval [CI] 1.04-1.55) but this was not observed among patients with appendicitis. Patients with renal failure had increased odds of hospital admission (OR 1.14, 95% CI 1.04-1.24) and 30-day mortality (OR 1.17, 95% CI 1.04-1.31) during the pandemic period.

Interpretation: The pandemic period was associated with increased arrival to the emergency department via ambulance across all study diagnoses. Although patients with renal failure had increased hospital admission and death, and patients with ectopic pregnancy had an increased risk of surgery, there were no differences in outcomes for other populations, suggesting the health care system was able to care for these patients effectively.

Background: In Canada, all provinces implemented vaccine passports in 2021 to reduce SARS-CoV-2 transmission in non-essential indoor spaces and increase vaccine uptake (policies active September 2021-March 2022 in Quebec and Ontario). We sought to evaluate the impact of vaccine passport policies on first-dose SARS-CoV-2 vaccination coverage by age, and area-level income and proportion of racialized residents.

Methods: We performed interrupted time series analyses using data from Quebec's and Ontario's vaccine registries linked to census information (population of 20.5 million people aged ≥ 12 yr; unit of analysis: dissemination area). We fit negative binomial regressions to first-dose vaccinations, using natural splines adjusting for baseline vaccination coverage (start: July 2021; end: October 2021 for Quebec, November 2021 for Ontario). We obtained counterfactual vaccination rates and coverage, and estimated the absolute and relative impacts of vaccine passports.

Results: In both provinces, first-dose vaccination coverage before the announcement of vaccine passports was 82% (age ≥ 12 yr). The announcement resulted in estimated increases in coverage of 0.9 percentage points (95% confidence interval [CI] 0.4-1.2) in Quebec and 0.7 percentage points (95% CI 0.5-0.8) in Ontario. This corresponds to 23% (95% CI 10%-36%) and 19% (95% CI 15%-22%) more vaccinations over 11 weeks. The impact was larger among people aged 12-39 years. Despite lower coverage in lower-income and more-racialized areas, there was little variability in the absolute impact by area-level income or proportion racialized in either province.

Interpretation: In the context of high vaccine coverage across 2 provinces, the announcement of vaccine passports had a small impact on first-dose coverage, with little impact on reducing economic and racial inequities in vaccine coverage. Findings suggest that other policies are needed to improve vaccination coverage among lower-income and racialized neighbourhoods and communities.

Background: The COVID-19 pandemic was associated with increased mental health problems in the general population, yet psychiatric hospital admissions decreased. Early evidence suggested that psychiatric admissions normalized within weeks; we sought to examine the longer-lasting impacts on the psychiatric inpatient population beyond this initial period.

Methods: We compared Ontario Mental Health Reporting System admission data for patients admitted to 8 psychiatric hospitals in Ontario, Canada, between 3 time periods - before restrictions were imposed (June 22, 2019, to Mar. 16, 2020), during restrictions (Mar. 17 to June 21, 2020) and after restrictions were lifted (June 22, 2020, to Mar. 16, 2021) for changes in involuntary status, diagnoses and clinical presentation using descriptive analysis. For clinical presentation, we extracted scores on 4 Resident Assessment Instrument-Mental Health symptom scales (Depressive Severity Index, Cognitive Performance Scale, Positive Symptoms Scale-Long Version and Social Withdrawal Scale), and 2 behaviour scales (Aggressive Behavior Scale and Violence Sum).

Results: A cross-sectional sample of 9848 patients was included in the analysis. The mean number of daily admissions decreased 19% from 16.4 (standard deviation [SD] 8.0) before the restriction period to 13.3 (SD 6.1) during the restriction period, and was still 6% below prerestriction levels after restrictions were lifted 15.4 (SD 6.8), with standard error difference of 1.03 (95% confidence interval -0.22 to 2.29). From the pre- to the postrestriction periods, the proportion of involuntary patients increased by 6 percentage points, and the proportions of patients diagnosed with a psychotic disorder or personality disorder increased by 4 percentage points and 1 percentage point, respectively.

Interpretation: Psychiatric admissions did not fully return to prerestriction levels in absolute rates and patient acuity after COVID-19 restrictions were lifted. Psychiatric services must prepare to appraise and respond to any increased acuity through interventions for patients, workforce planning and mental health support for staff.

Background: Academic detailing, an educational outreach service for family physicians, was funded by the Ontario government to address gaps in opioid prescribing and pain management. We sought to evaluate the impact of academic detailing on opioid prescribing, and to understand how and why academic detailing may have influenced opioid prescribing.

Methods: In this mixed-methods study, we collected quantitative and qualitative data concurrently from 2017 to 2019 in Ontario, Canada. We analyzed prescribing outcomes descriptively for a sample of participating physicians and compared them with a matched control group. We invited physicians to participate in qualitative interviews to discuss their experiences in academic detailing. Development and analysis of qualitative interviews was informed by the Theoretical Domains Framework. We triangulated qualitative and quantitative findings to understand the mechanisms that drove changes in opioid prescribing.

Results: Physicians receiving academic detailing (n = 238) achieved a greater reduction in opioid prescribing than matched controls (n = 238). Seventeen physicians completed interviews and reported that academic detailing addressed barriers to pain care, including lack of confidence, difficult interactions with patients and prescribing and tapering decisions. Academic detailing reinforced knowledge about opioid prescribing and pain management. Discussion of complex patients and talking points to use during challenging conversations were described as key drivers of practice change.

Interpretation: The findings of this real-world, mixed-methods evaluation explain how an academic detailing service addressed key barriers and enablers to limit high-risk opioid prescribing in primary care. This nuanced understanding will be used to inform, spread and scale academic detailing.

Background: Addressing the risk of people from gender and sexual minority (GSM) groups experiencing inequities throughout the cancer continuum requires a robust evidence base. In this scoping review, we aim to map the literature on cancer outcomes among adults from GSM groups and the factors that influence them along the cancer continuum.

Methods: This mixed-methods scoping review will follow the approach outlined by JBI. We will systematically search electronic databases for literature in collaboration with a health sciences librarian. Two reviewers will screen titles and abstracts to determine eligibility based on inclusion criteria, and then retrieve full text articles for data extraction. Results will be reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews. Quantitative data will be qualitized through a narrative interpretation and pooled with qualitative data. We will use meta-aggregation to synthesize findings. This protocol was developed in collaboration with GSM patient and public advisors. We will engage people from GSM groups, community organizations and knowledge users in disseminating results.

Interpretation: This review will direct future research efforts by expanding the wider body of research examining cancer disparities across the cancer continuum that GSM groups experience, identifying literature gaps and limitations, and highlighting relevant social determinants of health that influence cancer outcomes for adults from GSM groups.