Kate Smolina

Background: Stroke mortality rates have declined in recent decades; however, data on contemporary drivers of this trend are limited. This study compared the contribution of trends in stroke event rates and 30-day case fatality to declines in stroke mortality from 2002 to 2018. Methods: Linked hospitalization and mortality data were obtained from Western Australia (WA), England, New Zealand, British Columbia (BC), and Ontario. Age-standardized and age-specific stroke mortality and event rates and 30-day case fatality were calculated and age-adjusted trends estimated from Poisson and binomial regression models. The relative contribution of trends in stroke events and 30-day case fatality to trends in stroke mortality were calculated. Results: There were 2 248 242 stroke events identified. Age-adjusted reductions in event rates ranged from −0.96%/year [95% confidence interval (CI) − 1.22, 0.70%] in men in WA to −2.51%/year (95% CI −2.61, −2.40%) in women in Ontario. Age-standardized 30-day case fatality was highest in England in 2002 (men 43.7%, women 45.5%), but declined at a greater rate than in other jurisdictions. Declines in stroke mortality ranged from −3.3%/year to −5.5%/year. Reductions in 30-day case fatality were the major contributor to declines in stroke mortality [range: men, 63.5% (Ontario)–80.9% (England); women, 55.3% (BC)–73.1% (England)]. In people aged <65 years, stroke mortality declines were almost completely driven by reductions in 30-day case fatality with increasing or attenuated event rates among those aged 35–64 years. Conclusion: Improvements in 30-day case fatality had a greater impact on stroke mortality than trends in event rates, suggesting that further gains could be achieved with targeted prevention. Adverse trends in event rates in people aged <65 years could signal future increases in stroke mortality.

Background The impact of the COVID-19 pandemic on the population’s mental health is vital for informing public health policy and decision-making. However, information on mental health-related healthcare service utilisation trends beyond the first year of the pandemic is limited. Aims We examined mental health-related healthcare service utilisation patterns and psychotropic drug dispensations in British Columbia, Canada, during the COVID-19 pandemic compared with the prepandemic period. Methods We conducted a retrospective population-based secondary analysis using administrative health data to capture outpatient physician visits, emergency department visits, hospital admissions and psychotropic drug dispensations. We examined time trends of mental health-related healthcare service utilisation and psychotropic drug dispensations between January to December 2019 (prepandemic period) and January 2020 to December 2021 (pandemic period). In addition, we calculated age-standardised rates and rate ratios to compare mental health-related healthcare service utilisation before and during the first two years of the COVID-19 pandemic, stratified by year, sex, age and condition. Results By late 2020, except for emergency department visits, utilisation of healthcare services recovered to prepandemic levels. Between 2019 and 2021, the monthly average rate for overall mental health-related outpatient physician visits, emergency department visits and psychotropic drug dispensations increased significantly by 24%, 5% and 8%, respectively. Notable and statistically significant increases were observed among 10–14 year-olds (44% in outpatient physician visits, 30% in emergency department visits, 55% in hospital admissions and 35% in psychotropic drug dispensations) and 15–19 year-olds (45% in outpatient physician visits, 14% in emergency department visits, 18% in hospital admissions and 34% in psychotropic drug dispensations). Additionally, these increases were more prominent among females than males, with some variation for specific mental health-related conditions. Conclusions The increase in mental health-related healthcare service utilisation and psychotropic drug dispensations during the pandemic likely reflects significant societal consequences of both the pandemic and pandemic management measures. Recovery efforts in British Columbia should consider these findings, especially among the most affected subpopulations, such as adolescents.

Background People with immune dysfunction have a higher risk for severe COVID-19 outcomes. Omicron variant is associated with a lower rate of hospitalization but higher vaccine escape. This population-based study quantifies COVID-19 hospitalization rate in the Omicron-dominant era among vaccinated people with immune dysfunction, identified as clinically extremely vulnerable (CEV) population before COVID-19 treatment was widely offered. Methods All COVID-19 cases were reported to the British Columbia Centre for Disease Control (BCCDC) between January 7, 2022 and March 14, 2022. Case and population hospitalization rates were estimated across CEV status, age groups and vaccination status. Cumulative rates of hospitalizations for the study period were also compared between CEV and non-CEV individuals matched by sex, age group, region, and vaccination characteristics. Findings A total of 5,591 COVID-19 reported cases and 1,153 hospitalizations among CEV individuals were included. A third vaccine dose with mRNA vaccine offered additional protection against severe illness in CEV individuals. Vaccinated CEV population still had a significantly higher breakthrough hospitalization rate compared with non-CEV individuals. Interpretation CEV population remains a higher risk group and may benefit from additional booster doses and pharmacotherapy. Funding BC Centre for Disease Control and Provincial Health Services Authority

BACKGROUND The impact of the coronavirus disease (COVID-19) pandemic on mental health of the population is important for informing public health policy and decision-making. However, there is limited information on trends in mental health-related healthcare service utilization during the pandemic. OBJECTIVE This study aimed to describe patterns of mental health-related healthcare service utilisation and psychotropic drug dispensations in British Columbia, Canada, during the COVID-19 pandemic compared to a pre-pandemic period. We explored trajectories of use across multiple data sources to determine whether the patterns were similar or different in acute and outpatient settings, and how these patterns differed by age, sex and type of condition. METHODS We conducted a population-based study using administrative health data to capture outpatient physician visits, emergency department visits, hospital admissions, and psychotropic drug dispensations. We examined time trends of mental health-related healthcare utilisation and psychotropic drug dispensations between January 2019 and December 2021. We calculated age-standardised rates and rate ratios to compare healthcare service utilisation before and during the COVID-19 pandemic and stratified by year, sex, age and condition. RESULTS Results: In April 2020, compared to the same period in 2019, we observed a 26% and 16% decrease in acute care visits for mental health-related emergency department visits and hospital admissions, respectively. By late 2020, with the exception of emergency department visits, healthcare service utilisation recovered to pre-pandemic (2019) levels. In 2021, overall mental health-related healthcare service utilisation increased to above pre-pandemic levels, with an increase in the monthly average rate of 22% for outpatient physician visits only and not in other datasets. However, notable and statistically significant increases in healthcare utilisation were observed across all data sources among 10-14 year olds (45% in outpatient physician visits, 31% in emergency department visits, 55% in hospital admissions, and 36% in psychotropic drug dispensations), and 15-19 year olds (51% in outpatient physician visits, 19% in emergency department visits, 13% in hospital admissions, and 39% in psychotropic drug dispensations). Increases were more prominent among females than males, but there was some variation for specific mental health-related conditions. CONCLUSIONS The increase in mental health-related healthcare utilisation and psychotropic drug dispensations in 2020 and 2021 likely reflects important societal consequences of both the pandemic itself and the associated measures. Recovery efforts in British Columbia should take these findings into consideration, especially among most affected sub-populations, such as adolescents. CLINICALTRIAL Not applicable.

This study identified factors associated with hospital admission among people with laboratory-diagnosed COVID-19 cases in British Columbia. The study used data from the BC COVID-19 Cohort, which integrates data on all COVID-19 cases with data on hospitalizations, medical visits, emergency room visits, prescription drugs, chronic conditions and deaths. The analysis included all laboratory-diagnosed COVID-19 cases in British Columbia to 15 January 2021. We evaluated factors associated with hospital admission using multivariable Poisson regression analysis with robust error variance. Of the 56,874 COVID-19 cases included in the analysis, 2298 were hospitalized. Factors associated with increased hospitalization risk were as follows: male sex (adjusted risk ratio (aRR) = 1.27; 95% CI = 1.17–1.37), older age (p-trend < 0.0001 across age groups increasing hospitalization risk with increasing age [aRR 30–39 years = 3.06; 95% CI = 2.32–4.03, to aRR 80+ years = 43.68; 95% CI = 33.41–57.10 compared to 20–29 years-old]), asthma (aRR = 1.15; 95% CI = 1.04–1.26), cancer (aRR = 1.19; 95% CI = 1.09–1.29), chronic kidney disease (aRR = 1.32; 95% CI = 1.19–1.47), diabetes (treated without insulin aRR = 1.13; 95% CI = 1.03–1.25, requiring insulin aRR = 5.05; 95% CI = 4.43–5.76), hypertension (aRR = 1.19; 95% CI = 1.08–1.31), injection drug use (aRR = 2.51; 95% CI = 2.14–2.95), intellectual and developmental disabilities (aRR = 1.67; 95% CI = 1.05–2.66), problematic alcohol use (aRR = 1.63; 95% CI = 1.43–1.85), immunosuppression (aRR = 1.29; 95% CI = 1.09–1.53), and schizophrenia and psychotic disorders (aRR = 1.49; 95% CI = 1.23–1.82). In an analysis restricted to women of reproductive age, pregnancy (aRR = 2.69; 95% CI = 1.42–5.07) was associated with increased risk of hospital admission. Older age, male sex, substance use, intellectual and developmental disability, chronic comorbidities, and pregnancy increase the risk of COVID-19-related hospitalization.

Background: The province of British Columbia (BC) has been recognized for successful SARS-CoV-2 control, with surveillance data showing amongst the lowest case and death rates in Canada. We estimate sero-prevalence for two periods flanking the start (March) and end (May) of first-wave mitigation measures in BC. Methods: Serial cross-sectional sampling was conducted using anonymized residual sera obtained from an outpatient laboratory network, including children and adults in the Greater Vancouver Area (population ∼3 million) where community attack rates were expected to be highest. Screening used two chemiluminescent immuno-assays for spike (S1) and nucleocapsid antibodies. Samples sero-positive on either screening assay were assessed by a third assay targeting the S1 receptor binding domain plus a neutralization assay. Age-standardized sero-prevalence estimates were based on dual-assay positivity. The May sero-prevalence estimate was extrapolated to the source population to assess surveillance under-ascertainment, quantified as the ratio of estimated infections versus reported cases. Results: Serum collection dates spanned March 5-13 and May 15-27, 2020. In March, two of 869 specimens were dual-assay positive, with age-standardized sero-prevalence of 0.28% (95%CI=0.03-0.95). Neither specimen had detectable neutralizing antibodies. In May, four of 885 specimens were dual-assay positive, with age-standardized sero-prevalence of 0.55% (95%CI=0.15-1.37%). All four specimens had detectable neutralizing antibodies. We estimate ∼8 times more infections than reported cases. Conclusions: Less than 1% of British Columbians had been infected with SARS-CoV-2 when first-wave mitigation measures were relaxed in May 2020. Our findings indicate successful suppression of community transmission in BC, but also substantial residual susceptibility. Further sero-survey snapshots are planned as the pandemic unfolds. Key points: Cross-sectional sampling of anonymized residual sera at the start and end of first-wave mitigation measures in British Columbia, Canada shows SARS-CoV-2 sero-prevalence below 1% throughout the winter-spring 2020. Findings indicate successful suppression of community transmission but also substantial residual susceptibility.

Background: We sought to quantify the association between clinical, physiological, and contextual factors and opioid-related overdose, specifically focusing on current and past use of select prescription medications. Methods: We conducted a case-control study of individuals who experienced a non-fatal opioid-related overdose between January 2015 and November 2016 in British Columbia, Canada. We matched 8,831 cases to 44,155 controls on birth year, sex, and local health area of residence and examined 5-year prescribing history for opioids for pain, medications for opioid use disorder (MOUD), benzodiazepines/z-drugs, and other psychoactive medications. Results: The overall prevalence of prescription opioid drug use was generally low in the study population. Cases had a relatively higher use of selected prescription medications, a higher physical and mental morbidity burden, and were less connected to health services compared with controls. For opioids for pain, current therapy was associated with experiencing an overdose (OR = 8.5, 95%CI: 7.3–10); history of long-term use had a stronger association than history of short-term use (OR = 2.9, 95%CI: 2.6–3.3 vs OR = 1.7, 95%CI: 1.5–1.8, respectively). While persons on MOUD were more likely to overdose compared to persons who were not on therapy (OR = 2.0, 95%CI 1.7–2.4), recent discontinuation of MOUD greatly increased the likelihood of overdose (OR = 25.6, 95%CI 17.5–37.4). Active therapy of benzodiazepines/z-drugs and other sedating medications also significantly increased the likelihood of overdose. Conclusions: While this study supports expansion of efforts to prevent overdoses among individuals actively using opioids for pain and improve retention among those on MOUD, it is also important to address other clinical, physiological, and contextual risk and protective factors to help curb the current overdose crisis.

Objective To evaluate the effects of the 2016 College of Physicians and Surgeons of British Columbia's (CPSBC's) opioid and benzodiazepine and z drug prescribing standards on the use of these medications in British Columbia. Design Interrupted time-series analysis of community-prescribing records over a 30-month period: January 2015 to June 2017. Setting British Columbia. Participants Random sample of British Columbia residents with filled prescriptions during the study period. Intervention Introduction of CPSBC's opioid and benzodiazepine and z drug prescribing standards on June 1, 2016. Main outcome measures Total weekly consumption of opioids (measured in morphine equivalents) and benzodiazepines and z drugs (measured in diazepam equivalents); and total monthly users of each class of medication. Results Total consumption of both medication classes began to decline in late 2015, and the rate of decrease did not statistically significantly change following the implementation of the CPSBC standards in June 2016. In contrast, introduction of the standards was associated with an immediate 2% decrease in the number of monthly users of opioids for pain (P<.001), culminating in a 9% decrease over the course of the following year (P<.001). This trend was driven largely by a decrease in the number of continuing users; minimal change was seen in the number of new users during the study period. Trends in monthly users of benzodiazepines and z drugs mirrored those seen for opioids for pain. Conclusion Implementation of the 2016 CPSBC standards did not change a preexisting downward trend in consumption of opioids or benzodiazepines and z drugs that began 6 months earlier. However, the standards did have a small effect on the number of monthly users of these medications, with a decrease in opioid prescribing among continuing users. Given the risk of destabilization of patients who are discontinued from opioid therapy, future research should assess how patient health outcomes are related to changing prescribing practices.