Dina H. Lavorato

Major depression as a risk factor for chronic disease incidence: longitudinal analyses in a general population cohort ☆

OBJECTIVE Cross-sectional studies have consistently reported associations between major depression (MD) and chronic medical conditions. Such studies cannot clarify whether medical conditions increase the risk for MD or vice versa. The latter possibility has received relatively little attention in the literature. In this study, we evaluate the incidence of several important chronic medical conditions in people with and without MD. METHOD The data source was the Canadian National Population Health Survey (NPHS). The NPHS included the Composite International Diagnostic Interview Short Form to assess past-year major depressive episodes. The NPHS also collected self-report data about professionally diagnosed long-term medical conditions. A longitudinal cohort was interviewed every 2 years between 1994 and 2002. Proportional hazards models were used to compare the incidence of chronic conditions in respondents with and without MD and to produce age-, sex- and covariate-adjusted estimates of the hazard ratios. RESULTS The adjusted hazard ratios associated with MD at baseline interview were elevated for several long-term medical conditions: heart disease (1.7), arthritis (1.9), asthma (2.1), back pain (1.4), chronic bronchitis or emphysema (2.2), hypertension (1.7) and migraines (1.9). The incidences of cataracts and glaucoma, peptic ulcers and thyroid disease were not higher in respondents with MD. CONCLUSION A set of conditions characterized particularly by pain, inflammation and/or autonomic reactivity has a higher incidence in people with MD.

Major Depression as a Risk Factor for High Blood Pressure : Epidemiologic Evidence From a National Longitudinal Study

Objective: To determine whether major depression (MD) leads to an increased risk of new-onset high blood pressure diagnoses. Methods: The data source was the Canadian National Population Health Survey (NPHS). The NPHS included a short-form version of the Composite International Diagnostic Interview (CIDI-SF) to assess MD and collected self-report data about professionally diagnosed high blood pressure and the use of antihypertensive medications. The analysis included 12,270 respondents who did not report high blood pressure or the use of antihypertensive medications at a baseline interview conducted in 1994. Proportional hazards models were used to compare the incidence of high blood pressure in respondents with and without MD during 10 years of subsequent follow-up. Results: After adjustment for age, the risk of developing high blood pressure was elevated in those with MD. The hazard ratio was 1.6 (95% Confidence Interval = 1.2–2.1), p = .001, indicating a 60% increase in risk. Adjustment for additional covariates did not alter the association. Conclusions: MD may be a risk factor for new-onset high blood pressure. Epidemiologic data cannot definitely confirm a causal role, and the association may be due to shared etiologic factors. However, the increased risk may warrant closer monitoring of blood pressure in people with depressive disorders. MD = major depression; HR = hazard ratio; CI = Confidence Interval; NPHS = National Population Health Survey; OR = odds ratio; CARDIA Study = Coronary Artery Risk Development in Young Adults; CES-D = Center for Epidemiologic Studies Depression Rating Scale; CIDI-SF = Composite International Diagnostic Interview Short Form.

Descriptive Epidemiology of Major Depressive Disorder in Canada in 2012

Objective: The epidemiology of major depressive disorder (MDD) was first described in the Canadian national population in 2002. Updated information is now available from a 2012 survey: the Canadian Community Health Study—Mental Health (CCHS-MH). Method: The CCHS-MH employed an adaptation of the World Health Organization World Mental Health Composite International Diagnostic Interview and had a sample of n = 25 113. Demographic variables, treatment, comorbidities, suicidal ideation, and perceived stigma were assessed. The analysis estimated adjusted and unadjusted frequencies and prevalence ratios. All estimates incorporated analysis methods to account for complex survey design effects. Results: The past-year prevalence of MDD was 3.9% (95% CI 3.5% to 4.2%). Prevalence was higher in women and in younger age groups. Among respondents with past-year MDD, 63.1% had sought treatment and 33.1% were taking an antidepressant (AD); 4.8% had past-year alcohol abuse and 4.5% had alcohol dependence. Among respondents with past-year MDD, the prevalence of cannabis abuse was 2.5% and that of dependence was 2.9%. For drugs other than cannabis, the prevalence of abuse was 2.3% and dependence was 2.9%. Generalized anxiety disorder was present in 24.9%. Suicide attempts were reported by 6.6% of respondents with past-year MDD. Among respondents accessing treatment, 37.5% perceived that others held negative opinions about them or treated them unfairly because of their disorder. Conclusions: MDD is a common, burdensome, and stigmatized condition in Canada. Seeking help from professionals was reported at a higher frequency than in prior Canadian studies, but there has been no increase in AD use among Canadians with MDD.

Depression and suicide ideation in late adolescence and early adulthood are an outcome of child hunger

BACKGROUND Child hunger represents an adverse experience that could contribute to mental health problems in later life. The objectives of this study were to: (1) examine the long-term effects of the reported experience of child hunger on late adolescence and young adult mental health outcomes; and (2) model the independent contribution of the child hunger experience to these long-term mental health outcomes in consideration of other experiences of child disadvantage. METHODS Using logistic regression, we analyzed data from the Canadian National Longitudinal Survey of Children and Youth covering 1994 through 2008/2009, with data on hunger and other exposures drawn from NLSCY Cycle 1 (1994) through Cycle 7 (2006/2007) and mental health data drawn from Cycle 8 (2008/2009). Our main mental health outcome was a composite measure of depression and suicidal ideation. RESULTS The prevalence of child hunger was 5.7% (95% CI 5.0-6.4). Child hunger was a robust predictor of depression and suicidal ideation [crude OR=2.9 (95% CI 1.4-5.8)] even after adjustment for potential confounding variables, OR=2.3 (95% CI 1.2-4.3). LIMITATIONS A single question was used to assess child hunger, which itself is a rare extreme manifestation of food insecurity; thus, the spectrum of child food insecurity was not examined, and the rarity of hunger constrained statistical power. CONCLUSIONS Child hunger appears to be a modifiable risk factor for depression and related suicide ideation in late adolescence and early adulthood, therefore prevention through the detection of such children and remedy of their circumstances may be an avenue to improve adult mental health.

A longitudinal community study of major depression and physical activity

BACKGROUND The objective of this study was to determine whether major depressive episodes (MDEs) are associated transitions between active and inactive recreational activity patterns. METHODS The data source was the Canadian National Population Health Survey (NPHS). The NPHS included a brief instrument to assess MDEs and collected data on participation in recreational activities. In order to meaningfully categorize participation in recreational activities, the participation data was translated into overall estimated metabolic energy expenditure. A threshold of 1.5 kcal/kg per day was used to distinguish between active and inactive activity patterns. Proportional hazards models were used to compare the incidence of inactivity in initially active respondents with and without MDE and to compare the frequency of becoming active among initially inactive respondents with and without MDE. RESULTS For active respondents with MDE, an elevated risk of transition into an inactive pattern was observed [adjusted hazard ratio (HR)=1.6; 95% CI 1.2-1.9]. However, MDE did not affect the probability of moving from an inactive to an active lifestyle (adjusted HR=1.0; 95% CI 0.78-1.19). CONCLUSIONS Major depressive episodes are associated with an increased risk of transition from an active to an inactive pattern of activity.

ALCOHOL CONSUMPTION AND MAJOR DEPRESSION IN THE GENERAL POPULATION: THE CRITICAL IMPORTANCE OF DEPENDENCE

Substance use disorders and major depressive episodes (MDEs) often co‐occur. Alcohol consumption may contribute to the aetiology of depressive episodes and/or vice versa. In Canada, the National Population Health Survey (NPHS) evaluated several aspects of alcohol use and MDE in a large population cohort over 12 years of follow‐up. We evaluated the incidence of MDE in relation to different patterns of alcohol use, and examined the incidence of alcohol misuse in respondents with and without MDE.

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.

Major depression, antidepressant medication and the risk of obesity.

Background: Cross-sectional studies have reported an association between major depressive episode (MDE) and obesity. The objective of this longitudinal analysis was to determine whether MDE increase the risk of becoming obese over a 10-year period. Method: We used data from the Canadian National Population Health Survey (NPHS), a longitudinal study of a representative cohort of household residents in Canada. The incidence of obesity, defined as a body mass index (BMI) of ≥30, was evaluated in respondents who were 18 years or older at the time of a baseline interview in 1994. MDE was assessed using a brief diagnostic instrument. Results: The risk of obesity was not elevated in association with MDE, either in unadjusted or covariate-adjusted analyses. The strongest predictor of obesity was a BMI in the overweight (but not obese) range. Effects were also seen for (younger) age, (female) sex, a sedentary activity pattern, low income and exposure to antidepressant medications. Unexpectedly, significant effects were seen for serotonin-reuptake-inhibiting antidepressants and venlafaxine, but neither for tricyclic antidepressants nor antipsychotic medications. Conclusions: MDE does not appear to increase the risk of obesity. The cross-sectional associations that have been reported, albeit inconsistently, in the literature probably represent an effect of obesity on MDE risk. Pharmacologic treatment with antidepressants may be associated with an increased risk of obesity, and strategies to offset this risk may be useful in clinical practice.

The incidence of major depression in Canada: the National Population Health Survey.

OBJECTIVES To estimate the cumulative incidence of major depressive episode (MDE) over 6 years and the associations between demographic and socioeconomic variables and MDE in a sample of the Canadian national population. METHODS Data from the longitudinal cohort of the Canadian National Population Health Survey (NPHS) were used. MDE was assessed using the Composite International Diagnostic Interview - Short Form for Major Depression. Participants of the 2000/01 NPHS were followed until 2006/07. Individuals with previous MDE were excluded from the analysis. Proportional hazard models were developed to assess the associations between demographic, socioeconomic characteristics and MDE. RESULTS The cumulative incidence of MDE at 2002/03, 2004/05 and 2006/07 was 2.9% (95% confidence interval: 2.3%, 3.4%), 5.7% (95% confidence interval: 4.9%, 6.4%) and 7.2% (95% confidence interval: 6.4%, 8.1%). Women, youth, participants with one or more chronic medical conditions and those who reported family history of MDE were more likely to have developed MDE. Family history was the strongest risk factor for MDE (hazard ratio=2.01, 95% confidence interval: 1.51, 2.68). CONCLUSION It may be valuable for primary and secondary prevention efforts to target women and young people. Family history is an important factor which should be considered in epidemiological studies about major depression, and also can assist in identifying those at high risk of new-onset MDE.

Weight gain in relation to major depression and antidepressant medication use

BACKGROUND Previous studies have linked major depressive episodes (MDEs) to obesity. The association may be partially mediated by antidepressant medication use. In the current study we examine changes in weight and BMI in relation to MDE and antidepressant use in a general population cohort. METHODS Data from a Canadian longitudinal study, the National Population Health Survey (NPHS) were used. The NPHS has collected data from a community cohort since 1994 using interviews spaced two years apart. The NPHS includes the Composite International Diagnostic Interview Short Form for Major Depression (CIDI-SFMD). Self-reported height and weight are also recorded. Linear regression was used to describe associations between weight, BMI and MDE. RESULTS The pattern of weight change varied by age. Respondents under the age of 65 tended to gain weight over time, whereas those over the age of 65 tended to lose weight. Respondents in the younger category gained more weight if they had MDE or took antidepressant medications. However, the extent of weight gain was modest, those with MDE and those taking an antidepressant gaining an average of approximately 1 kg over 12 years of follow-up. LIMITATIONS The study used self-reported weight, which may be inaccurate. Measurements were made two years apart. The measure of MDE was an abbreviated diagnostic interview. CONCLUSIONS Both MDE and antidepressant medication use are associated with a modest increase in weight in people under 65. These results may be useful for physicians and other health professionals in planning dietary and weight-management regimens for depressed patients.