Trends in vaping and smoking behavior before and during the COVID-19 pandemic in Canada: Beneficial and potentially detrimental changes.

INTRODUCTION: E-cigarette and cigarette use may have changed during the COVID-19 pandemic, however, there is no consensus in existing literature, and current Canadian studies have not used representative samples. Thus, there is a need for robust national estimates. OBJECTIVE AND METHODS: The primary objective was to describe the 30-day period prevalence of smoking and vaping before and during the COVID-19 pandemic in Canada. This study analyzed three years of the cross-sectional Canadian Tobacco and Nicotine Survey: 2019 (pre-pandemic), 2020 (9 months into the pandemic) and 2021 (21 months into pandemic). RESULTS: Thirty-day period prevalence of vaping over the 2019, 2020, and 2021 study periods were 4.8 (95%CI: 4.2-5.3), 4.6% (95%CI: 4.1-5.2), and 5.2% (95%CI: 4.7-5.7), respectively. The 30-day period prevalence of smoking over the 2019, 2020, and 2021 study periods were 11.9% (95%CI: 10.9-12.7), 10.3% (95%CI: 9.4-11.2), and 10.3% (95%CI: 9.4-11.1), respectively. Notably, estimates of smoking for females decreased considerably from 2019 (11.0%; 95%CI: 9.9--12.2%) to 2020 (8.6%; 95%CI: 7.5-9.7). Estimates of vaping in those aged 20-24 increased substantially from 2020 (13.0%; 95%CI: 10.9-15.1) to 2021 (17.2%; 95%CI: 15.4-18.9). CONCLUSIONS: Changes to smoking and vaping were restricted to subsets within the population. In those aged 20-24, there was a modest increase in vaping from 2020 to 2021. In females, there was a decrease in smoking from 2019 to 2020, which persisted in 2021.

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.

Alternative scoring of the Patient Health Questionnaire-9 in neurological populations: an approach based on a predictive algorithm deriving from individual item scores.

OBJECTIVE: The study objective was to assess whether machine learning methods could improve predictive performance of the PHQ-9 for depression in patients with neurological disease. Specifically, we assessed whether a predictive algorithm deriving from all nine items could outperform the tradition of summing the items and applying a cut-point. METHOD: Data from the NEEDS Study was used (n = 825). Demographic data, PHQ-9 scores, and MDD diagnoses (via the SCID) were obtained. Logistic LASSO, logistic regression, and non-parametric ROC analyses were performed. The ROC curve was used to identify the optimal cut-point for regression-derived predictive algorithms using the Youden method. RESULTS: The traditional approach to PHQ-9 scoring had a classification accuracy of 85.1% (sensitivity: 84.5%; specificity: 85.2%). The logistic LASSO regression model had a classification accuracy of 85.6% (sensitivity: 83.3%; specificity: 86.1%). The logistic regression model had a classification accuracy of 85.8% (sensitivity: 91.4%; specificity: 84.8%). Both models had similar areas under the curve values (logistic LASSO: 0.9097; logistic regression: 0.9026). CONCLUSIONS: The current cut-off threshold approach to PHQ-9 scoring and interpretation remains clinically appropriate.

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.

Major depressive episodes and mortality in the Canadian household population.

OBJECTIVE: To explore the association between major depressive episodes (MDE) and subsequent mortality in a representative sample of the general household population, with adjustment for other determinants of mortality. METHOD: The analysis used four datasets from the Canadian Community Health Survey (CCHS); the CCHS 1.1 (conducted in 2000 and 2001), the CCHS 1.2 (conducted in 2002), the CCHS 2.1 (conducted in 2003 and 2004) and the CCHS 3.1 (conducted in 2005 and 2006). Each survey included an assessment of past-year major depressive episodes (MDEs) and was linked to mortality data from the Canadian Mortality Database for January 1, 2000 to December 31, 2011. The hazard ratio (HR) for all-cause mortality was estimated in each survey sample. Random effects, individual-level meta-analysis was used to pool estimates from the four survey data sets. Estimates were adjusted for other determinants of mortality prior to pooling in order to help quantify the independent contribution of MDE to all-cause mortality. RESULTS: The unadjusted HR was 0.77 (95% CI 0.63-0.95). A naïve interpretation of this HR suggests a protective effect of MDE, but the estimate was found to be strongly confounded by age (age adjusted HR for MDE: 1.61, 95% CI 1. 34-1.93) and by sex (sex adjusted HR for MDE: 1.15, 95% CI 0.75-1.77). The age and sex adjusted HR was: 1.70 (95% CI 1.45-2.00). No evidence of effect modification by any determinant of mortality was found, including sex. After adjustment for a set of mortality risk factors, the pooled HR was weakened, but remained statistically significant, HR = 1.29 (I-squared = < 1%, tau-squared < 0.001, 95% CI 1.10-1.51). Smoking was the strongest single confounding variable. CONCLUSIONS: MDE is associated with elevated mortality. The elevated risk is partially attributable to psychosocial, behavioral and health-related determinants. Since MDE itself may have caused changes to these variables, these estimates cannot fully quantify the independent contribution of MDE to mortality. However, these results suggest that clinical and public health efforts to counteract the effect of MDE on mortality may benefit from attention to a broad set of mortality risk factors e.g. smoking, physical activity, management of medical conditions.

Depression as a risk factor for the development of rheumatoid arthritis: a population-based cohort study.

OBJECTIVES: Major depressive disorder (MDD) is associated with increased levels of systemic proinflammatory cytokines, including tumour necrosis factor alpha. As these cytokines are pathogenic in autoimmune diseases such as rheumatoid arthritis (RA), our aim was to explore on a population-level whether MDD increases the risk of developing RA. METHODS: A retrospective cohort study was conducted using The Health Improvement Network (THIN) database (from 1986 to 2012). Observation time was recorded for both the MDD and referent cohorts until patients developed RA or were censored. Cox proportional hazards models were used to determine the risk of developing RA among patients with MDD, accounting for age, sex, medical comorbidities, smoking, body mass index and antidepressant use. RESULTS: A cohort of 403 932 patients with MDD and a referent cohort of 5 339 399 patients without MDD were identified in THIN. Cox proportional hazards models revealed a 31% increased risk of developing RA among those with MDD in an unadjusted model (HR=1.31, 95% CI 1.25 to 1.36, p<0.0001). When adjusting for all covariates, the risk remained significantly increased among those with MDD (HR=1.38, 95% CI 1.31 to 1.46, p<0.0001). Antidepressant use demonstrated a confounding effect that was protective on the association between MDD and RA. CONCLUSION: MDD increased the risk of developing RA by 38%, and antidepressants may decrease this risk in these patients. Future research is necessary to confirm the underlying mechanism of MDD on the pathogenesis of RA.

Major depression and secondhand smoke exposure.

BACKGROUND: Epidemiological studies have consistently linked smoking to poor mental health. Among non-smokers, some studies have also reported associations between secondhand smoke exposure and psychological symptoms. However, an association between secondhand smoke exposure and depressive disorders has not been well established. METHODS: This analysis used cross-sectional data from a series of 10 population surveys conducted in Canada between 2003 and 2013. The surveys targeted the Canadian household population, included a brief structured interview for past year major depressive episode (MDE) and included items assessing secondhand smoke exposure. We used two-stage individual-level random-effects meta-regression to synthesize results from these surveys. RESULTS: Over the study interval, about 20% of non-smokers reported substantial exposure to secondhand smoke. In this group, the pooled annual prevalence of MDE was 6.1% (95% CI 5.3-6.9) compared to 4.0% (95% CI 3.7-4.3) in non-smokers without secondhand smoke exposure. The crude odds ratio was 1.5 (95% CI 1.4-1.7). With adjustment for a set of potential confounding variables the odds ratio was unchanged, 1.4 (95% CI 1.2 - 1.6). CONCLUSIONS: These results provide additional support for public health measures aimed at reducing secondhand smoke exposure. A causal connection between secondhand smoke exposure and MDEs cannot be confirmed due to the cross-sectional nature of the data. Longitudinal studies are needed to establish temporal sequencing.

The prevalence of anxiety and associated factors in persons with epilepsy.

The objectives of this study were to estimate the prevalence of, and factors associated with, anxiety in epilepsy. We conducted a cross-sectional analysis using data from the Neurological Disease and Depression Study. The prevalence of anxiety and associated factors were assessed using descriptive statistics and logistic regression. Of the total sample (n = 250 patients), nearly 40.0% of participants had anxiety according to the Hospital Anxiety and Depression Scale. The most prevalent symptom of anxiety was "worrying thoughts" (35.6%). After adjustment for age and sex, depression (odds ratio [OR] = 8.97, 95% confidence interval [CI] = 4.38-18.40), medication side effects (OR = 1.79, 95% CI = 1.04-3.05), smoking (OR = 4.35, 95% CI = 2.27-8.31), and illicit substance use (OR = 2.42, 95% CI = 1.18-4.96) were significantly associated with higher odds of anxiety, whereas higher education (OR = 0.47, 95% CI = 0.28-0.80) was associated with lower odds of anxiety. Furthermore, participants with anxiety reported more severe epilepsy, debilitating seizures, and overall lower quality of life. Evidence from our study reveals a high prevalence of anxiety in persons with epilepsy and that anxiety is associated with a variety of negative outcomes. These findings further emphasize the need for more studies to understand the impact of anxiety and its relationship with various sociodemographic and clinical factors.

Major depression and non-specific distress following smoking cessation in the Canadian general population.

BACKGROUND: Outcome data from smoking cessation trials indicate that improvement in mental health occurs after smoking cessation. This suggests that smoking cessation should be a priority for mental health services. However, participants in such trials may not be representative of the general population. This study investigates changes in mental health following smoking cessation in a set of general population samples. METHODS: Data from a library of cross-sectional surveys conducted by Statistics Canada between 2001 and 2013 were included in this analysis. Survey estimates were pooled in order to increase precision. Associations between smoking (and smoking cessation), major depressive episodes (MDE) and non-specific distress (assessed using the K-6 scale) were evaluated using meta-analysis and meta-regression techniques. RESULTS: The annual prevalence of major depression was higher in daily (11.0%) than in never smokers (4.4%). The prevalence in former daily smokers was 5.1%. The prevalence of MDE and distress was elevated in those recently quitting but returned to baseline levels within one year. CONCLUSIONS: After smoking cessation, indicators of mental health improve over time, especially in the first year. The findings support the idea that smoking cessation should be a part of the management of common mood and anxiety disorders. However, due to its observational nature this study in itself cannot confirm causality, sustained abstinence may be an effect of improved mental health rather than its cause. LIMITATIONS: The cross-sectional nature of the constituent surveys does not allow causal inference. No biological measures (e.g. cotinine) were available.

A comparison of recommendations and received treatment for mood and anxiety disorders in a representative national sample.

BACKGROUND: The exact nature of treatment and management recommendations made, and received, for mood and anxiety disorders in a community population is unclear. In addition, there is limited evidence on the impact of recommendations on actual receipt of treatment or implementation of management strategies. We aim to describe the frequency with which specific recommendations were made and implemented; and thus assess the size of any gap between the recommendation and implementation of treatments and management strategies. METHODS: We used the Survey 'Living with a Chronic Condition in Canada - Mood and Anxiety Disorders (SLCDC-MA), a unique crossectional survey of a large (N = 3358) and representative sample of Canadians with a diagnosed mood or anxiety disorder, which was conducted by Statistics Canada. The survey collected information on recommendations for medication, counselling, exercise, reduction of alcohol consumption, smoking cessation and reduction of street drug use. We also estimate the frequency that recommendations are made and followed, as well the impact of the prior on the latter. We consulted people with lived experience of the disorders to help interpret our results. RESULTS: The results generally showed that most people would receive recommendations, almost all for antidepressant medications (94.6%), with lower proportions for the other treatment and management strategies (e.g. 62.1 and 66% for counselling and exercise). Most recommendations were implemented and had an impact on behaviour. The exception to this was smoking reduction/cessation, which was often not recommended or followed through. Other than with medication, at least 20% of the population, for each recommendation, would not have their recommendation implemented. A substantive group also exists who access treatments, and employ various management strategies, without a recommendation. CONCLUSIONS: The results indicate that there is a gap between recommendations made and the implementation of treatments. However, its size varies substantially across treatments.

Depression Is Associated with an Increased Risk of Psoriatic Arthritis among Patients with Psoriasis: A Population-Based Study.

The factors that contribute to the development of psoriatic arthritis (PsA) among patients with psoriasis are not well known; however, systemic inflammation is believed to be important. On the basis of recent laboratory work demonstrating that major depressive disorder (MDD) is associated with increased systemic inflammation, we hypothesized that patients with psoriasis who develop MDD are at increased risk of subsequently developing PsA. We utilized The Health Improvement Network, a primary care medical records database, to identify 73,447 individuals with psoriasis. Patients were followed up to 25 years until the development of the primary outcome of PsA or the censor date. The exposure of interest was the development of MDD. Cox proportional-hazards models showed that patients with psoriasis who developed MDD were at significantly increased risk of subsequently developing PsA compared with patients who did not develop MDD, even after accounting for numerous covariates (hazard ratio 1.37, 95% confidence interval 1.05-1.80, P = 0.021). This result was maintained through numerous sensitivity analyses. These data support the hypothesis that MDD increases the risk of developing PsA among patients with psoriasis, suggesting a need for heightened prevention and management of MDD in patients with psoriasis.

Validating screening tools for depression in stroke and transient ischemic attack patients.

OBJECTIVE: The best screening questionnaires for detecting post-stroke depression have not been identified. We aimed to validate four commonly used depression screening tools in stroke and transient ischemic attack patients. METHODS: Consecutive stroke and transient ischemic attack patients visiting an outpatient stroke clinic in Calgary, Alberta (Canada) completed a demographic questionnaire and four depression screening tools: Patient Health Questionnaire (PHQ)-9, PHQ-2, Hospital Anxiety and Depression Scale (HADS-D), and Geriatric Depression Scale (GDS-15). Participants then completed the Structured Clinical Interview for DSM-IV (SCID), the gold-standard for diagnosing major depression. The questionnaires were validated against the SCID and sensitivity and specificity were calculated at various cut-points. Optimal cut-points for each questionnaire were determined using receiver-operating curve analyses. RESULTS: Among 122 participants, 59.5% were diagnosed with stroke and 40.5% with transient ischemic attack. The point prevalence of SCID-diagnosed current major depression was 9.8%. At the optimal cut-points, the sensitivity and specificity for each screening tool were as follows: PHQ-9 (sensitivity: 81.8%, specificity: 97.1%), PHQ-2 (sensitivity: 75.0%, specificity: 96.3%), HADS-D (sensitivity: 63.6%, specificity: 98.1%), and GDS-15 (sensitivity: 45.5%, specificity: 84.8%). Areas under the receiver operating characteristic curves were as follows: PHQ-9 86.6%, PHQ-2 86.7%, HADS-D 85.9%, and GDS-15 66.3%. CONCLUSIONS: The PHQ-2 and PHQ-9 are both suitable depression screening tools, taking less than 5 minutes to complete. The HADS-D does not appear to have any advantage over the PHQ-based scales, even though it was designed specifically for medically ill populations. The GDS-15 cannot be recommended for general use in a stroke clinic based on this study as it had worse discrimination due to low sensitivity.

Depression--a common disorder across a broad spectrum of neurological conditions: a cross-sectional nationally representative survey.

OBJECTIVE: To estimate the prevalence of depression across a range of neurological conditions in a nationally representative sample. METHODS: The data source was the Survey of Living with Neurological Conditions in Canada (SLNCC), which accrued its sample by selecting participants from the Canadian Community Health Survey. The point prevalence of depression was estimated by assessment of depressive symptoms with the Patient Health Questionnaire, Brief (Patient Health Questionnaire, 9-item). RESULTS: A total of n=4408 participated in the SLNCC. The highest point prevalence of depression (>30%) was seen in those with traumatic brain injury and brain/spinal cord tumors. Depression was also highly prevalent (18-28%) in those with (listed from highest to lowest) Alzheimer's disease/dementia, dystonia, multiple sclerosis, Parkinson's disease, stroke, migraine, epilepsy and spina bifida. The odds ratios for depression, with the referent group being the general population, were significant (from highest to lowest) for migraine, traumatic brain injury, stroke, dystonia and epilepsy. CONCLUSIONS: All neurological conditions included in this study are associated with an elevated prevalence of depression in community populations. The conditions with the highest prevalence are traumatic brain injury and brain/spinal cord tumors.

Persistent heavy smoking as risk factor for major depression (MD) incidence--evidence from a longitudinal Canadian cohort of the National Population Health Survey.

BACKGROUND: Reports of bidirectional associations between smoking and major depression (MD) have been interpreted as providing evidence for confounding by shared-vulnerability factors (SV) that predispose individuals to both conditions. If this is true, then smoking cessation may not reduce the risk of MD. From clinical practice and public health perspectives, the long-term outcomes associated with smoking persistence and cessation are potentially important and deserve exploration. To this end, the 12-year risk of MD in persistent heavy smokers and abstainers who were former-heavy smokers with and without adjustment for potential confounders were compared. METHODS: Follow-up data from the National Population Health Survey (NPHS) was used. Multinomial logistic (ML) models were fit to identify potential confounders. Using proportional hazard (PH) models, unadjusted and adjusted hazard ratios (HRs) for MD outcome were estimated for different smoking patterns. RESULTS: The unadjusted HR relating the risk of MD among current-heavy versus former-heavy smokers was 4.3 (95% CI: 2.6-6.9, p < 0.001). Current-heavy smoking predicted onset of MD (HR = 3.1, 95% CI: 1.9-5.2, p < 0.001) even after adjustment for age, sex and stress - the main confounders. However, this was not the case for the never, former-light, and current-light categories. Evidence of decreased risk of MD among former-heavy relative to current-heavy smokers as function of smoking cessation maintenance time was also found. CONCLUSIONS: Contrary to common beliefs about the benefits of smoking for mental health, our results suggest that current-heavy rather than ever-heavy smoking is a major determinant of MD risk and point towards the benefits of smoking cessation maintenance.

Major depression is a risk factor for shorter time to first cigarette irrespective of the number of cigarettes smoked per day: evidence from a National Population Health Survey.

INTRODUCTION: We assessed whether major depression (MD) predicts progression of nicotine dependence (ND) as measured by reduction in the time to first cigarette (TTFC) after waking and the roles of the number of cigarettes smoked per day (CPD) and stress as explanatory variables of this association. METHODS: Ten years of follow-up data from the National Population Health Survey (NPHS) were used. The analyses were based on this nationally representative sample of the Canadian population who were over the age of 12 years in 1996 (n = 13,298). The NPHS included measures of MD and TTFC. Shorter TTFC was defined as TTFC within 5 min of waking. Heavy smoking (HS) was defined by smoking 20 or more CPD. Using proportional hazard models, unadjusted and adjusted hazard ratios (HRs) for shorter TTFC were estimated for those with and without MD. RESULTS: The unadjusted HR for shorter TTFC among those with MD versus those without MD was 3.7 (95% CI: 2.6-5.3, p < .001). MD predicted onset of shorter TTFC even after adjustment for HS and tendency to smoke more under stress (HR: 1.7; 95% CI: 1.1-2.5, p = .02). When TTFC was defined using longer cutoffs (30 and 60 min), HS completely accounted for the effect of MD on TTFC onset. CONCLUSIONS: MD appears to be a risk factor for transition to shorter TTFC independent of effects of HS and the tendency to smoke more under stress. As MD is often modifiable, the above association points toward a preventive opportunity in relation to worsening of ND.

Predictors of the longitudinal course of major depression in a Canadian population sample.

OBJECTIVE: Most psychiatric epidemiologic studies have used cross-sectional methods, resulting in a lack of information about the longitudinal course of depressive disorders. The objective of our study was to describe the longitudinal epidemiology of major depressive episodes (MDEs) in a Canadian sample using data from the National Population Health Survey (NPHS). METHODS: The NPHS started data collection in 1994 and has evaluated past-year MDE using repeat interviews of the same cohort every 2 years since then. In our study, we examined the number of weeks depressed during years when MDEs occurred, the proportion of respondents having MDEs at consecutive cycles, and MDE counts during follow-up. RESULTS: A sizable proportion of MDEs were brief: about one-half of respondents with past-year MDE reported 8 or fewer weeks of depression during that year. Less than 10% reported that they were depressed for the entire year. However, a larger proportion (19.1%) fulfilled criteria for MDE on consecutive interview cycles, suggesting either persistence or rapid recurrence. The mean number of detected MDEs among those with at least 1 detected MDE up to 2006 was 2. Positive family history, evidence of comorbidity, negative cognitive style, stress, pain, and smoking were associated with a more negative course. CONCLUSIONS: The longitudinal course of MDE in the general population is heterogeneous, including a mixture of brief and more protracted MDEs. Many risk factors for MDE are also associated with a negative course, exceptions being (younger) age and sex. These epidemiologic observations may assist with identification of patients requiring more intensive management in clinical practice.

Cigarette smoking, stages of change, and major depression in the Canadian population.

OBJECTIVE: To describe the 12-month prevalence of major depression in relation to smoking status, nicotine dependence levels, commitment to quit, attempts to quit, and maintenance of smoking cessation in the Canadian general population. METHOD: Data from Public Use Microdata File of the Canadian Community Health Survey: Health and Well-Being were used. The Composite International Diagnostic Interview--Short Form (CIDI-SF) for major depression was used to assess depressive disorder status. The survey also included a smoking module. There were 49,249 respondents assessed by the CIDI-SF, of whom 10,236 were administered the smoking module. Analyses used appropriate measures to deal with survey design effects. RESULT: The prevalence of major depression was highest in current smokers, followed by ever smokers, former smokers, and was lowest in the never smokers. This pattern persisted after stratification for age and sex. For quitting, the prevalence of major depression was highest among people who tried to quit, followed by those who considered quitting, those who quit in the past year, and lowest among those who maintained their smoking cessation status for longer than 1 year. The prevalence of depression among those with a high nicotine dependence level, as assessed by the Fagerstrom Tolerance Questionnaire, was about twice that of people with a low nicotine dependence level. CONCLUSION: The strikingly high prevalence of major depression among current smokers who are young, trying to quit, and with high nicotine dependence levels in the general population indicates that further longitudinal exploration of this topic is urgently needed.