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The Evidence Speaks

The Evidence Speaks (June 2019)

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The Evidence Speaks Series is a recurring feature highlighting the latest in CHÉOS research. This series features summaries of select publications as well as in-depth features on the latest work from our investigators. In the early days of CHÉOS, the Centre had a series known as “The Evidence Speaks,” a monograph series to keep media and the research community up-to-date with CHÉOS’ current research results in the health outcomes field.

Doan Q, Wong H, Meckler G, Johnson D, Stang A, Dixon A, Sawyer S, Principi T, Kam AJ, Joubert G, Gravel J, Jabbour M, Guttmann A; Pediatric Emergency Research Canada (PERC). The impact of pediatric emergency department crowding on patient and health care system outcomes: A multicentre cohort study. CMAJ. 2019 Jun;191(23):E627-35.

CHÉOS Biostatistics Program Head Dr. Hubert Wong was part of a recent national collaboration that aimed to determine the effect of pediatric emergency department (ED) overcrowding on hospital admission and mortality. Previous research in adults suggests that overcrowding is associated with decreased quality of care and patient satisfaction and increased mortality and morbidity. Although there has been some research on the causes of overcrowding and impacts on quality of care, there is a lack of studies looking at patient outcomes and health services use. The research team looked at nearly 2 million visits to 8 pediatric EDs across 4 provinces over a period of 4 years. All visits were grouped into either high, medium, or low acuity: almost 90% of pediatric visits were medium or low acuity. Overcrowding was assessed as the average departmental length of stay during the 8-hour period before a patient arrived to the ED; this value ranged from 2.9 hours to 3.6 hours. Only between 0.8 and 1.5 per cent of visits resulted in hospitalization within 7 days of the first visit and less than 0.01% resulted in death within 2 weeks of ED discharge. Overall, there was no association between crowding and hospital admission or mortality. However, among the most acute children (high and medium acuity), increased crowding was associated with hospital admission within 7 days of the first visit. This could be due to delays in timely medical attention and patient deterioration leading to hospitalization or due to clinicians exercising increased caution during times of overcrowding. In the low-acuity group, overcrowding was associated with increased odds of return visits to the ED. This effect of overcrowding in the pediatric setting, which varied by acuity, has not been previously demonstrated but suggests that it likely has implications for health services use across the country.

Money D, Lee T, O’Brien C, Brophy J, Bitnun A, Kakkar F, Boucoiran I, Alimenti A, Vaudry W, Singer J, Sauvé LJ; Canadian Perinatal HIV Surveillance Program. Congenital anomalies following antenatal exposure to dolutegravir: A Canadian surveillance study. BJOG. June 12 epub ahead of print.

CHÉOS Clinical Trials Program Head Dr. Joel Singer and Statistician Terry Lee are co-authors on a recent publication looking at rates of congenital anomalies in babies born to women living with HIV. The analysis also explored potential associations between rates of anomalies and type of antiretroviral medication used during pregnancy. The researchers were particularly interested in characterizing the potential effect of dolutegravir, an antiretroviral treatment that has become increasingly popular due to its tolerability, efficacy, and cost. Despite its popularity and endorsement from the World Health Organization, there is limited pregnancy safety data for this treatment. A recent study from Botswana suggested that rates of neural tube defect, a type of congenital anomaly, were higher in infants born to women taking dolutegravir than other antiretrovirals. The researchers used data from the Canadian Perinatal HIV Surveillance Program, a program which gathers data from 95% of pregnancies in women living with HIV in Canada, to compare pregnancy outcomes to the general population and between HIV treatment types. From 2007 to 2017, the surveillance program captured data on 2,591 infants born to women living with HIV. There were 98 cases of anomalies (4%); this rate was not affected by dolutegravir exposure. The incidence of neural defects was not statistically different between women living with HIV (0.12%) and the general population (0.04%). There were no cases of neural tube defects in infants born to mothers taking dolutegravir. However, the analysis revealed that the rate of neural tube defects in infants born to women taking elvitegravir (a different antiretroviral therapy) during the first trimester was 10.7%. This finding was from only a small number of pregnancies (28) and therefore requires further study. Overall, there was no clear indication of increased risk of congenital anomaly with antiretroviral therapy during pregnancy, including dolutegravir.

Oviedo-Joekes E, Palis H, Guh D, Marchand K, Brissette S, Harrison S, MacDonald S, Lock K, Anis AH, Marsh DC, Schechter MT. Treatment with injectable hydromorphone: Comparing retention in double blind and open label treatment periods. J Sub Abuse Treat. 2019 Jun;101:50-4.

A team of researchers from CHÉOS, led by Dr. Eugenia Oviedo-Joekes, recently published a paper analyzing treatment retention rates of patients receiving injectable hydromorphone (HDM) in the double-blind and open-label periods of the Study to Assess Longer-term Opioid Medication Effectiveness (SALOME). SALOME was a double-blind trial that compared the effectiveness and cost-effectiveness of HDM and diacetylmorphine (heroin; DIA) for the treatment of severe opioid use disorder. Following the conclusion of the study, enrolled participants who did not transfer to oral medication continued to access injectable HDM at the former SALOME site, Crosstown Clinic. Some patients were able to transition to receive injectable DIA at Crosstown through Health Canada’s Special Access Programme. Of the 150 SALOME participants, 129 transitioned to open-label HDM after the study, of which 21 eventually transitioned to DIA once they were granted Special Access. Twenty-one other participants transitioned to open-label DIA immediately after SALOME.  The research team was specifically interested in the retention of patients receiving HDM both before and after they knew which drug they were receiving. Retention in treatment was defined as receiving medication at least 28 out of the past 30 days at the 3-month mark. Average retention was 87 per cent during the double-blind phase and 77.8 per cent during the open-label phase with no significant difference between the two. Seventy-four patients (68.5 per cent) were successfully retained in both phases. Over a 90-day period, on average, patients received a similar number of days of treatment in the double-blind phase (84.4 days) and open-label phase (80.5). Although previous research in SALOME participants suggests that they prefer DIA over HDM, this new analysis demonstrates that an open-label treatment format with HDM can effectively retain patients. These results are particularly encouraging in light of the recent announcement from Health Canada approving injectable HDM as a treatment for severe opioid use disorder.