Neighborhood material versus social deprivation in Canada: different patterns of associations with child and adolescent mental health problems.

PURPOSE: In a nationwide study, we aimed to study the association of neighborhood deprivation with child and adolescent mental health problems. METHODS: We used data from the Canadian Health Survey on Children and Youth (N = 47,871; age range: 1-17 years) and linked these to Neighborhood Material and Social Deprivation data calculated using Canada's Census of Population. Using a series of logistic regressions, we studied the association between living in deprived areas and mental health problems among children and youth. We used bootstrap replicate weights for all analyses and adjusted them for individual sociodemographic characteristics. RESULTS: In the adjusted model, the parent-reported developmental disorder was associated with more socially deprived neighborhoods (OR 1.29; 95% CI 1.07, 1.57 for most vs. least deprived quintiles). However, mental health service need or use was associated with living in less materially deprived areas (OR 0.78; 95% CI 0.63, 0.96 for most vs. least deprived quintiles). Among mental health problems reported by the youth (12-17 years old), poor/fair general mental health, alcohol drinking, and cannabis use were associated with neighborhood social deprivation in the adjusted models. In contrast, poor/fair general mental health, suicide ideas, alcohol drinking, and cannabis use were all negatively associated with higher materially deprived quintiles. CONCLUSION: Our study provides further support for the existing evidence on the association between neighborhood deprivation, particularly social deprivation, and the mental health of children and adolescents. The findings can help public health policymakers and service providers better understand and address children's mental health needs in their neighborhoods.

Associations between negative COVID-19 experiences and symptoms of anxiety and depression: a study based on a representative Canadian national sample. / Associations entre les expériences négatives liées à la COVID-19 et les symptômes d'anxiété et de dépression : étude fondée sur un échantillon national canadien représentatif.

INTRODUCTION: Amid the widespread impact of the COVID-19 pandemic, a notable increase in symptoms of anxiety and depression has become a pressing concern. This study examined the prevalence of anxiety and depression symptoms in Canada from September to December 2020, assessing demographic and socioeconomic influences, as well as the potential role of COVID-19 diagnoses and related negative experiences. METHODS: Data were drawn from the Survey on COVID-19 and Mental Health by Statistics Canada, which used a two-stage sample design to gather responses from 14 689 adults across ten provinces and three territorial capitals, excluding less than 2% of the population. Data were collected through self-administered electronic questionnaires or phone interviews. Analytical techniques, such as frequencies, cross-tabulation and logistic regression, were used to assess the prevalence of anxiety and depression symptoms, the demographic characteristics of Canadians with increased anxiety and depression symptoms and the association of these symptoms with COVID-19 diagnoses and negative experiences during the pandemic. RESULTS: The study found that 14.62% (95% CI: 13.72%-15.51%) of respondents exhibited symptoms of depression, while 12.89% (95% CI: 12.04%-13.74%) reported anxiety symptoms. No clear differences in symptom prevalence were observed between those infected by COVID-19, or those close to someone infected, compared to those without these experiences. However, there were strong associations between traditional risk factors for depressive and anxiety symptoms and negative experiences during the pandemic, such as physical health problems, loneliness and personal relationship challenges in the household. CONCLUSION: This study provides insight into the relationship between COVID-19 and Canadians' mental health, demonstrating an increased prevalence of anxiety and depression symptoms associated with COVID-19-related adversities and common prepandemic determinants of these symptoms. The findings suggest that mental health during the pandemic was primarily shaped by traditional determinants of depression and anxiety symptoms and also by negative experiences during the pandemic.

Cancer risk, disease-modifying therapy, and age in multiple sclerosis: A retrospective population-based cohort study.

BACKGROUND: Long-term population-based safety studies are needed to investigate cancer outcomes in people with multiple sclerosis (MS) treated with modern disease-modifying therapy (DMT). OBJECTIVES: To investigate if exposure to DMT increases the risk of invasive cancer in MS. METHODS: We used population-based administrative health data from Alberta, Canada between 2008 and 2018. DMT exposure was defined in two ways: first as exposure to any DMT, and second by DMT type (modulating, sequestering, depleting). Study outcome was time to first diagnosis of invasive cancer. Cancer risk was compared to the general population using standardized incidence ratios (SIRs) and to the unexposed MS cases using hazard ratios (HRs). RESULTS: The analysis included 14,313 MS cases: 5,801 (40.5 %) were exposed to DMT. Median (interquartile range) follow-up was 8.4 (4.3, 10.4) years. Compared to the general population, there was no difference in cancer risk for the overall MS population (SIR: 0.94, 95 % confidence interval [CI]: 0.87, 1.02) or the DMT-exposed MS cases (SIR: 0.89; 95 % CI: 0.75, 1.05). Compared to unexposed MS cases, we found an interaction with age for exposure to any DMT (p = 0.001) and modulating DMT (p = 0.001), indicating that a difference in the risk of cancer associated with DMT depends on age. Cancer risk was not associated with exposure to sequestering DMT (HR: 1.28, 95 % CI: 0.78, 2.08) or depleting DMT (HR: 2.29, 95 % CI: 0.86, 6.14). CONCLUSIONS: Cancer risk for MS patients was similar to the general population. In the MS population, the age-dependent effect of DMT for cancer risk suggests a higher risk of cancer with age 62 or older and a protective effect at younger age. Further investigation is required to clarify whether the interaction between DMT exposure and age is a causal effect.

Association between childhood adversities and premature and potentially avoidable mortality in adulthood: a population-based study.

BACKGROUND: The association of childhood adversities with mortality has rarely been explored, and even less studied is the question of whether any excess mortality may be potentially preventable. This study examined the association between specific childhood adversities and premature and potentially avoidable mortality (PPAM) in adulthood in a representative sample of the general population. Also, we examined whether the associations were potentially mediated by various adult socioeconomic, psychosocial, and behavioral factors. METHODS: The study used data from the National Population Health Survey (NPHS-1994) linked to the Canadian Vital Statistics Database (CVSD 1994-2014) available from Statistics Canada. The NPHS interview retrospectively assessed childhood exposure to prolonged hospitalization, parental divorce, prolonged parental unemployment, prolonged trauma, parental problematic substance use, physical abuse, and being sent away from home for doing something wrong. An existing definition of PPAM, consisting of causes of death considered preventable or treatable before age 75, was used. Competing cause survival models were used to examine the associations of specific childhood adversities with PPAM in adulthood among respondents aged 18 to 74 years (rounded n = 11,035). RESULTS: During the 20-year follow-up, 5.4% of the sample died prematurely of a cause that was considered potentially avoidable. Childhood adversities had a differential effect on mortality. Physical abuse (age-adjusted sub-hazard ratio; SHR 1.44; 95% CI 1.03, 2.00) and being sent away from home (age-adjusted SHR 2.26; 95% CI 1.43,3.57) were significantly associated with PPAM. The associations were attenuated when adjusted for adulthood factors, namely smoking, poor perceived health, depression, low perceived social support, and low income, consistent with possible mediating effects. Other adversities under study were not associated with PPAM. CONCLUSION: The findings imply that the psychological sequelae of childhood physical abuse and being sent away from home and subsequent uptake of adverse health behavior may lead to increased risk of potentially avoidable mortality. The potential mediators identified offer directions for future research to perform causal mediation analyses with suitable data and identify interventions aimed at preventing premature mortality due to potentially avoidable causes. Other forms of adversities, mostly related to household dysfunction, may not be determinants of the distal health outcome of mortality.

Childhood adversities and rate of adulthood all-cause hospitalization in the general population: A retrospective cohort study.

OBJECTIVE: The study examined the association between specific childhood adversities and rate of all-cause hospitalization in adulthood in a large sample of the general population and assessed whether adult socioeconomic and health-related factors mediate those associations. METHODS: We used linked data available from Statistics Canada i.e., the Canadian Community Health Survey (CCHS-2005) linked to Discharge Abstract Database (DAD 2005-2017) and Canadian Vital Statistics Database (CVSD 2005-2017). CCHS-2005 measured self-reported exposure to childhood adversities, namely prolonged hospitalization, parental divorce, parental unemployment, prolonged trauma, parental substance use, physical abuse, and being sent away from home for wrongdoing, from a sample of household residents aged 18 years and above (n = 11,340). The number and causes of hospitalization were derived from linkage with DAD. Negative binomial regression was used to characterize the association between childhood adversities and the rate of hospitalization and to identify potential mediators between them. RESULTS: During the 12-year follow-up, 37,080 hospitalizations occurred among the respondents, and there were 2,030 deaths. Exposure to at least one childhood adversity and specific adversities (except parental divorce) were significantly associated with the hospitalization rate among people below 65 years. The associations (except for physical abuse) were attenuated when adjusted for one or more of the adulthood factors such as depression, restriction of activity, smoking, chronic conditions, poor perceived health, obesity, unmet health care needs, poor education, and unemployment, observations that are consistent with mediation effects. The associations were not significant among those aged 65 and above. CONCLUSION: Childhood adversities significantly increased the rate of hospitalization in young and middle adulthood, and the effect was potentially mediated by adulthood socioeconomic status and health and health care access related factors. Health care overutilization may be reduced through primary prevention of childhood adversities and intervention on those potentially mediating pathways such as improving adulthood socioeconomic circumstances and lifestyle modifications.

Childhood Adversity and Mental Health Outcomes Among University Students: A Longitudinal Study.

BACKGROUND: Mental health concerns are common among university students and maybe elevated among those with specific risk exposures. The study examined the association between childhood adversities and mental health outcomes among undergraduate university students and assessed whether psychosocial and behavioral factors mediate those associations. METHODS: The Queen's University Student Well-Being and Academic Success Survey identified two large cohorts of first-year undergraduate students entering university in Fall 2018 and 2019 (n = 5,943). At baseline, students reported sociodemographic information, family-related mental health history, childhood physical abuse, sexual abuse, peer bullying, and parental separation or divorce. Baseline and follow-up surveys in Spring 2019, Fall 2019, and Spring 2020 included validated measures of anxiety (7-item Generalized Anxiety Disorder) and depressive symptoms (9-item Patient Health Questionnaire ), non-suicidal self-harm, and suicidality, along with psychological processes and lifestyle variables. Repeated measures logistic regression using Generalized Estimating Equations was used to characterize the associations between childhood adversities and mental health outcomes and examine potential mediation. RESULTS: Adjusting for age, gender, ethnicity, familial mental illness, and parental education, any childhood abuse (odds ratio: 2.89; 95% confidence interval, 2.58 to 3.23) and parental separation or divorce (odds ratio: 1.29; 95% confidence interval, 1.12 to 1.50) were significantly associated with a composite indicator of mental health outcomes (either 9-item Patient Health Questionnaire score ≥10 or 7-item Generalized Anxiety Disorderscore ≥10 or suicidality or self-harm). The association with childhood abuse weakened when adjusted for perceived stress, self-esteem, and insomnia (odds ratio: 2.05; 95% confidence interval, 1.80 to 2.34), and that with parental divorce weakened when adjusted for self-esteem (odds ratio: 1.17; 95% confidence interval, 1.00 to 1.36). CONCLUSION: Childhood abuse and parental separation or divorce were associated with mental health concerns among university students. Childhood adversities may impact later mental health through an association with stress sensitivity, self-esteem, and sleep problems. The findings suggest that prevention and early intervention focusing on improving sleep, self-esteem, and coping with stress while considering the individual risk profile of help-seeking students may help support student mental health.

Transitions to campus mental health care in university students: Determinants and predictors.

Background: Access to university mental health services is poorly characterized. Our objectives were to (1) assess patterns of access and (2) explore predictability of contact with student mental health services. Participants: Data derived from the U-Flourish study, which includes a survey of successive cohorts of incoming undergraduate students attending Queen's University, located in Ontario, Canada (Cohort 1: 2018, Cohort 2: 2019). Methods: Survey data sets were deterministically linked to administrative data provided by Student Wellness Services. Analyses included cross-tabulation, logistic and negative binomial regression. Predictive modeling used LASSO regression. Results: Baseline symptoms were robust determinants of access. For example, a PHQ-9 rating in the severe range (≥ 20) was associated with an OR of 9.71 (95% CI: 4.46-21.1). A predictive algorithm did not outperform cut point-based interpretation of PHQ-9 or GAD-7 ratings. Conclusions: Self-reported symptoms are consistently associated with service use, supporting the widespread use of symptom screens.

Self-Reported Lifetime History of Eating Disorders and Mortality in the General Population: A Canadian Population Survey with Record Linkage.

Eating disorders (EDs) are often reported to have the highest mortality of any mental health disorder. However, this assertion is based on clinical samples, which may provide an inaccurate view of the actual risks in the population. Hence, in the current retrospective cohort study, mortality of self-reported lifetime history of EDs in the general population was explored. The data source was the Canadian Community Health Survey: Mental Health and Well-Being (CCHS 1.2), linked to a national mortality database. The survey sample was representative of the Canadian household population (mean age = 43.95 years, 50.9% female). The survey inquired about the history of professionally diagnosed chronic conditions, including EDs. Subsequently, the survey dataset was linked to the national mortality dataset (for the date of death) up to 2017. Cox proportional hazards models were used to explore the effect of EDs on mortality. The unadjusted-hazard ratio (HR) for the lifetime history of an ED was 1.35 (95% CI 0.70-2.58). However, the age/sex-adjusted HR increased to 4.5 (95% CI 2.33-8.84), which was over two times higher than age/sex-adjusted HRs for other mental disorders (schizophrenia/psychosis, mood-disorders, and post-traumatic stress disorder). In conclusion, all-cause mortality of self-reported lifetime history of EDs in the household population was markedly elevated and considerably higher than that of other self-reported disorders. This finding replicates prior findings in a population-representative sample and provides a definitive quantification of increased risk of mortality in EDs, which was previously lacking. Furthermore, it highlights the seriousness of EDs and an urgent need for strategies that may help to improve long-term outcomes.

Can the adverse childhood experiences (ACEs) checklist be utilized to predict emergency department visits among children and adolescents?

BACKGROUND: Extensive literature has shown an association of Adverse Childhood Experiences (ACEs) with adverse health outcomes; however, its ability to predict events or stratify risks is less known. Individuals with mental illness and ACE exposure have been shown to visit emergency departments (ED) more often than those in the general population. This study thus examined the ability of the ACEs checklist to predict ED visits within the subsequent year among children and adolescents presenting to mental health clinics with pre-existing mental health issues. METHODS: The study analyzed linked data (n = 6100) from two databases provided by Alberta Health Services (AHS). The Regional Access and Intake System (RAIS 2016-2018) database provided data on the predictors (ACE items, age, sex, residence, mental health program type, and primary diagnosis) regarding children and adolescents (aged 0-17 years) accessing addiction and mental health services within Calgary Zone, and the National Ambulatory Care Reporting System (NACRS 2016-2019) database provided data on ED visits. A 25% random sample of the data was reserved for validation purposes. Two Least Absolute Shrinkage and Selection Operator (LASSO) logistic regression models, each employing a different method to tune the shrinkage parameter lambda (namely cross-validated and adaptive) and performing 10-fold cross-validation for a set of 100 lambdas in each model were examined. RESULTS: The adaptive LASSO model had a slightly better fit in the validation dataset than the cross-validated model; however, it still demonstrated poor discrimination (AUC 0.60, sensitivity 37.8%, PPV 49.6%) and poor calibration (over-triaged in low-risk and under-triaged in high-risk subgroups). The model's poor performance was evident from an out-of-sample deviance ratio of - 0.044. CONCLUSION: The ACEs checklist did not perform well in predicting ED visits among children and adolescents with existing mental health concerns. The diverse causes of ED visits may have hindered accurate predictions, requiring more advanced statistical procedures. Future studies exploring other machine learning approaches and including a more extensive set of childhood adversities and other important predictors may produce better predictions. Furthermore, despite highly significant associations being observed, ACEs may not be deterministic in predicting health-related events at the individual level, such as general ED use.

Outdoor Air Pollution and Depression in Canada: A Population-Based Cross-Sectional Study from 2011 to 2016.

To assess whether exposure to increased levels of outdoor air pollution is associated with psychological depression, six annual iterations of the Canadian Community Health Survey (n ≈ 127,050) were used to estimate the prevalence of a major depressive episode (2011-2014) or severity of depressive symptoms (2015-2016). Survey data were linked with outdoor air pollution data obtained from the Canadian Urban Environmental Health Research Consortium, with outdoor air pollution represented by fine particulate matter ≤2.5 micrometers (µm) in diameter (PM2.5), ozone (O3), sulfur dioxide (SO2), and nitrogen dioxide (NO2). Log-binomial models were used to estimate the association between outdoor air pollution and depression, and included adjustment for age, sex, marital status, income, education, employment status, urban versus rural households, cigarette smoking, and chronic illness. No evidence of associations for either depression outcomes were found. Given the generally low levels of outdoor air pollution in Canada, these findings should be generalized with caution. It is possible that a meaningful association with major depression may be observed in regions of the world where the levels of outdoor air pollution are greater, or during high pollution events over brief time intervals. Future research is needed to replicate these findings and to further investigate these associations in other regions and populations.

Physical Activity and Mental Health: A Cross-sectional Study of Canadian Youth.

OBJECTIVE: Our objective was to examine the associations between recreational and non-recreational physical activity with mental health outcomes among Canadian youth aged 12-17. METHODS: Cross-sectional data from the 2015/2016 Canadian Community Health Survey was used for analysis. Physical activity was classified as either recreational or non-recreational. Both types of physical activity were categorized using the Canadian Physical Activity Guidelines. Mental health outcomes included the Patient Health Questionnaire-9 (PHQ-9) scale dichotomized with 5+ and 10+ cut-offs, self-perceived mental health, and self-reported professionally diagnosed mood and anxiety disorders. Descriptive statistics (proportions with 95% confidence intervals), and multivariable logistic regression were used in the analysis. RESULTS: It was found 21.20% of youth were not participating in recreational physical activity and 40.97% were engaging in below guideline recreational physical activity. No activity, or below guideline recreational physical activity was associated with negative mental health. Non-recreational physical activity models were generally non-significant. Additionally, it was determined that associations between recreational physical activity and PHQ-9 score were only evident in males. For the no activity and below guideline activity levels the odds ratios (ORs)=2.57 and 3.19 for males and OR=0.95 and 0.96 for females, respectively. CONCLUSIONS: Recreational physical activity is associated with youth mental health (particularly in males), but non-recreational physical activity is not consistently associated. While the data are cross-sectional and cannot support causal inference, these results highlight the potential importance of accessible recreational physical activity programs. Further, these results may inform guidelines about types of youth physical activity and their apparent mental health benefits.

OBJECTIF: Notre objectif était d'examiner les associations entre l'activité physique récréative et non récréative et les résultats de santé mentale chez les adolescents canadiens de 12 à 17 ans. MÉTHODES: Les données transversales de l'Enquête sur la santé dans les collectivités canadiennes de 2015­2016 ont servi à l'analyse. L'activité physique était classée récréative ou non récréative. Les deux types d'activité physique ont été répartis en catégories selon les Lignes directrices canadiennes en matière d'activité physique. Les résultats de santé mentale comportaient le Questionnaire sur la santé du patient-9 (QSP-9), une échelle dichotomisée avec 5+ et 10+ seuils d'inclusion, la santé mentale auto-perçue, et les troubles de l'humeur et anxieux diagnostiqués professionnellement et auto-déclarés. Les statistiques descriptives (les proportions ayant des intervalles de confiance à 95 %) et la régression logistique multivariée ont été utilisées dans l'analyse. RÉSULTATS: Il a été constaté que 21,20 % des adolescents ne participaient pas à des activités physiques récréatives et que 40,97 % s'adonnaient à des activités physiques récréatives inférieures aux lignes directrices. Aucune activité ou des activités physiques récréatives inférieures aux lignes directrices étaient associées à une santé mentale négative. Les modèles d'activité physique non récréative étaient généralement non significatifs. En outre, il a été déterminé que les associations entre l'activité physique récréative et le score au QSP-9 n'étaient manifestes que chez les garçons. Pour l'absence d'activité et les niveaux d'activité inférieurs aux lignes directrices, les rapports de cotes (RC) = 2,57 et 3,19 pour les garçons et RC = 0,95 et 0,96 pour les filles, respectivement. CONCLUSIONS: L'activité physique récréative est associée à la santé mentale des adolescents (particulièrement chez les garçons), mais l'activité physique non récréative n'est pas associée constamment. Bien que les données soient transversales et qu'elles ne puissent soutenir une inférence causale, ces résultats soulignent l'importance potentielle de programmes accessibles d'activité physique récréative. De plus, ces résultats peuvent éclairer les lignes directrices au sujet des types d'activités physiques des adolescents et de leurs avantages apparents pour la santé mentale.

Mental disorders and subsequent suicide events in a representative community population.

OBJECTIVE: This study examined the patterns of association between mental disorders and subsequent suicide in a community sample representative of the Canadian household population. METHODS: This retrospective cohort study used data from the Canadian Community Health Survey 2002 linked to the Death Database 2000-2011 and the Hospitalization Database 1999/2000-2012/2013) (n=27,000). Mental disorders (past year major depressive episodes (MDE), bipolar disorders (BPD), anxiety disorders (AD), and substance dependence (SD)) and subsequent suicide events (deaths or hospitalizations for suicide attempts) were identified. Competing risk regression models were used to analyze the time-to-event data, adjusting for age, sex, marital status, and educational attainment. RESULTS: Past year mental disorders were diagnosed in 11.38% of the cohort and 0.41% had suicide events. An increased hazard of suicide events associated with MDE, SD and AD weakened over-time, but this was not observed for BPD. For example, the HR of suicide events for MDE was 6.02 (95% confidence interval (CI)=2.65, 13.68) in the first 4 years, whereas, it was 2.03 (95% CI=0.91, 4.53) after 4 years. Whereas, the HRs of suicide events for BPD were 16.95 (95% CI=6.88, 41.75) and 15.81 (95% CI=5.89, 42.45) before and after 4 years. LIMITATIONS: Diagnostic data are likely to underestimate the prevalence of suicide events. CONCLUSIONS: The risk of suicide events declined over time for MDE, SA and AD, but remained high for BPD. This may reflect improvement over time in MDE, SA and AD, but indicates that people living with BPD have a persistent elevated hazard of suicide events.

The Association of Active Living Environments and Mental Health: A Canadian Epidemiological Analysis.

Environments that promote use of active transport (walking, biking, and public transport use) are known as "active living environments" (ALE). Using a Canadian national sample, our aim was to determine if ALEs were associated with mental health outcomes, including depressive symptoms, and mood and anxiety disorders. Data from the Canadian Community Health Survey from 2015-2016 was used for demographic characteristics and mental health outcomes (n ≈ 110,000). This data was linked to datasets from the Canadian Urban Environmental Health Research Consortium, reporting ALE and social and material deprivation. Depressive symptoms were evaluated using standard dichotomized scores of 5+ (mild) and 10+ (moderate/severe) from the Patient Health Questionnaire-9. Self-reported diagnosed mood and anxiety disorders were also included. Logistic regression was used to determine the association of mental health outcomes with four classes of ALE. The analysis included adjustments for social and material deprivation, age, sex, chronic conditions, marital status, education, employment, income, BMI, and immigrant status. No association between any mental health outcome and ALE were observed. While the benefits of ALE to physical health are known, these results do not support the hypothesis that more favorable ALE and increased use of active transport is associated with better mental health outcomes.

Mental Health among Canadian Postsecondary Students: A Mental Health Crisis?

OBJECTIVE: Recent reports express concerns about a mental health crisis among postsecondary students. These assertions, however, often arise from surveys conducted in postsecondary settings that lack the broader context of a referent group. The objectives of this study were (1) to assess the mental health status of postsecondary students 18 to 25 years old from 2011 to 2017 and (2) to compare the mental health status of postsecondary students to nonstudents. METHODS: Prevalence was estimated for a set of mental health outcomes using seven annual iterations of the Canadian Community Health Survey (2011 to 2017). Logistic regression was used to derive odds ratio estimates comparing mental health status among postsecondary students and nonstudents, adjusting for age and sex. Random effects metaregression and meta-analyses techniques were used to evaluate trends in prevalence and odds ratio estimates over time. RESULTS: Over the study period, the prevalence of perceived low mental health, diagnosed mood and anxiety disorders, and past-year mental health consultations increased among female students, whereas binge drinking decreased among male students. With the exception of perceived stress, the odds of experiencing each mental health outcome were lower among postsecondary students compared to nonstudents. CONCLUSIONS: These findings do not support the idea that postsecondary students have worse mental health than nonstudents of similar age. The perception of a crisis may arise from greater help-seeking behavior, diminishing stigma, or increasing mental health literacy. Regardless, the observance of these trends provide an opportunity to address a previously latent issue.

Seasonal variation in specific depressive symptoms: A population based study.

INTRODUCTION: Depression varies with season in Canadian youth. However, the symptom profile of seasonal depression may differ from that of non-seasonal depression. Here we evaluate which specific symptoms vary by season. METHODS: Using data from the 2015/2016 Canadian Community Health Survey, cross-sectional analysis was conducted. The Patient Health Questionnaire-9 (PHQ-9) was administered to respondents in 8 provinces/territories (n ≈ 53,000), with interviews conducted throughout the year. Seasonal effects were assessed using quadratic terms in a logistic regression model. Guided by previous literature and analysis, analyses were stratified by age into youth (age 12-24) and adult (age 25+) groups. RESULTS: In the youth, 8 items of the PHQ-9 exhibited a significant season variation: lack of interest/pleasure, feeling depressed/down, hypersomnia/insomnia, lacking energy, poor appetite/overeating, feeling bad about yourself/ like a failure, being slow/fidgety, and trouble concentrating. In the adult group, only sleep and poor appetite/overeating exhibited a seasonal effect. Notably, symptoms of self-harm/suicide did not demonstrate seasonality in either group. LIMITATIONS: Due to use of cross-sectional data and a brief symptom rating scale, conventional criteria for Seasonal Affective Disorder or Major Depressive Disorder with seasonal variation could not be applied. Also, treatment status of respondents was not assessed in the survey, therefore possible confounding by this variable could not be assessed. CONCLUSIONS: A seasonal pattern was observed in most symptoms of depression in Canadian youth, whereas in adults, only symptoms related to sleep and appetite disturbance displayed seasonal variation.

Predicting death by suicide using administrative health care system data: Can feedforward neural network models improve upon logistic regression models?

BACKGROUND: Suicide is a leading cause of death worldwide. With the increasing volume of administrative health care data, there is an opportunity to evaluate whether machine learning models can improve upon statistical models for quantifying suicide risk. OBJECTIVE: To compare the relative performance of logistic regression and single hidden layer feedforward neural network models that quantify suicide risk with predictors available in administrative health care system data. METHODS: The modeling dataset contained 3548 persons that died by suicide and 35,480 persons that did not die by suicide between 2000 and 2016. 101 predictors were selected, and these were assembled for each of the 40 quarters (10 years) prior to the quarter of death, resulting in 4040 predictors in total for each person. Logistic regression and single hidden layer feedforward neural network model configurations were evaluated using 10-fold cross-validation. RESULTS: The optimal feedforward neural network model configuration (AUC: 0.8352) outperformed logistic regression (AUC: 0.8179). LIMITATIONS: Many important predictors are not available in administrative data and this likely places a limit on how well prediction models developed with administrative data can perform. CONCLUSIONS: Although the models developed in this study showed promise, further research is needed to determine the performance limits of statistical and machine learning models that quantify suicide risk, and to develop prediction models optimized for implementation in clinical settings.