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.

Descriptive Epidemiology of Generalized Anxiety Disorder in Canada.

OBJECTIVE: The first national survey to assess the prevalence of generalized anxiety disorder (GAD) in Canada was the 2012 Canadian Community Health Survey: Mental Health and Well-Being (CCHS-MH). The World Mental Health Composite International Diagnostic Interview (WMH-CIDI), used within the representative sample of the CCHS-MH, provides the best available description of the epidemiology of this condition in Canada. This study uses the CCHS-MH data to describe the epidemiology of GAD. METHOD: The analysis estimated proportions and odds ratios and used logistic regression modelling. All results entailed appropriate sampling weights and bootstrap variance estimation procedures. RESULTS: The lifetime prevalence of GAD is 8.7% (95% CI, 8.2% to 9.3%), and the 12-month prevalence is 2.6% (95% CI, 2.3% to 2.8%). GAD is significantly associated with being female (OR 1.6; 95% CI, 1.3 to 2.1); being middle-aged (age 35-54 years) (OR 1.6; 95% CI, 1.0 to 2.7); being single, widowed, or divorced (OR 1.9; 95% CI, 1.4 to 2.6); being unemployed (OR 1.9; 95% CI, 1.5 to 2.5); having a low household income (<$30 000) (OR 3.2; 95% CI, 2.3 to 4.5); and being born in Canada (OR 2.0; 95% CI, 1.4 to 2.8). CONCLUSIONS: The prevalence of GAD was slightly higher than international estimates, with similar associated demographic variables. As expected, GAD was highly comorbid with other psychiatric conditions but also with indicators of pain, stress, stigma, and health care utilization. Independent of comorbid conditions, GAD showed a significant degree of impact on both the individual and society. Our results show that GAD is a common mental disorder within Canada, and it deserves significant attention in health care planning and programs.

The Prevalence of Major Depressive Episodes Is Higher in Urban Regions of Canada.

OBJECTIVE: Major depressive disorder is an important contributor to disease burden. Anticipation of service needs is important, yet basic information is lacking. For example, there is no consensus as to whether major depressive episodes (MDE) are more or less prevalent in urban or rural areas. The objective of this study was to determine whether a difference exists in Canada. METHOD: A series of 11 Canadian national cross-sectional studies were examined from 2000 to 2014, providing much greater precision than prior analyses. Survey-specific MDE prevalence estimates were synthesized into a pooled odds ratio comparing urban to rural areas using meta-analytic methods. RESULTS: Differences in the survey-specific estimates were not in excess of what would be expected due to sampling variability. This suggests that inconsistency in the prior literature is due to inadequate power and precision, an issue addressed by the meta-analytic pooling. The pooled odds ratio for Canada is 1.18 (95% confidence interval, 1.12 to 1.25), indicating that urban regions have higher MDE prevalence than rural regions. However, the difference is very small and of uncertain significance for policy and planning. CONCLUSIONS: Prevalence of MDE is approximately 18% higher in urban compared to rural regions of Canada. The difference is insufficient to impute differing need for services, but the result resolves an inconsistency in the existing literature and may play a role in future needs assessment.

Major Depression Prevalence Increases with Latitude in Canada.

OBJECTIVE: To determine whether there is an association between latitude and annual major depressive episode (MDE) prevalence in Canada. METHODS: Data from 2 national survey programs (the National Population Health Survey and the Canadian Community Health Survey) were used, providing 10 data sets collected between 1996 and 2013, together including 922,260 respondents, of whom 495,739 were assessed for MDE using 1 of 2 versions of the Composite International Diagnostic Interview, a short-form version (8 studies), and a Canadian adaptation of the World Mental Health version (2 studies). Approximate latitude was determined by linkage to postal code data. Data were analyzed using logistic regression and pooled across surveys using individual-level meta-analytic methods. RESULTS: In models including latitude as a continuous variable, a statistically significant association was observed, with prevalence increasing with increasing latitude. This association persisted after adjustment for a set of known risk factors. The latitude gradient was modest in magnitude, a 1% to 2% increase in the prevalence odds of MDE per degree of latitude was observed. Due to sparse data, this gradient cannot be confidently generalized beyond major population centres, which tend to occur at less than 55° latitude in Canada. CONCLUSION: A latitude gradient has not previously been reported. If replicated, the gradient may have implications for the planning of services and generation of aetiological hypotheses. However, this cross-sectional analysis cannot confirm aetiology and could not evaluate the potential contributions of variables such as light exposure, weather patterns, or social determinants.

Major Depression in Canada: What Has Changed over the Past 10 Years?

OBJECTIVE: Major depressive episodes (MDE) make an important contribution to disease burden in Canada. The epidemiology of MDE in the national population has been examined in 2 mental health surveys, one conducted in 2002 and the other in 2012. Our objective was to compare selected variables from the 2 surveys to determine whether changes have occurred in the prevalence, treatment, and impact of MDE. METHOD: The World Health Organization World Mental Health Composite International Diagnostic Interview was used in both surveys and the MDE module (which was not modified) was scored using the same algorithm. Some variables assessing impact and management of MDE were also identical in the 2 surveys. The analysis was based on frequency estimates and associated 95% confidence intervals. RESULTS: The annual prevalence of MDE was 4.7% (95% CI 4.3% to 5.1%) in 2012, nearly identical to 4.8% (95% CI 4.5% to 5.1%) in 2002. Receipt of potentially adequate treatment (defined as taking an antidepressant or 6 or more visits to a health professional for mental health reasons) increased from 41.3% in 2002 to 52.2% in 2012, mostly due to an increase in respondents reporting 6 or more visits. Use of second generation antipsychotics also increased. There was no evidence of diminishing prevalence or impact (as assessed by symptoms of distress). CONCLUSIONS: There appears to have been an increase in receipt of treatment for people with MDE and a changing pattern of management. However, it was not possible to confirm that the impact of MDE is diminishing as a result.

Perceived Stigma among Recipients of Mental Health Care in the General Canadian Population.

OBJECTIVES: The Mental Health Experiences Scale is a measure of perceived stigma, the perception of negative attitudes and behaviours by people with mental disorders. A recent Canadian survey (Canadian Community Health Survey-Mental Health) included this scale, providing an opportunity to describe perceived stigma in relation to diagnosis for the first time in the Canadian general population. METHODS: The survey interview began with an assessment of whether respondents had utilised services for an "emotional or mental health problem" in the preceding 12 months. The subset reporting service utilisation were asked whether others "held negative opinions" about them or "treated them unfairly" for reasons related to their mental health. The analysis reported here used frequencies, means, cross-tabulation, and logistic regression, all incorporating recommended replicate sampling weights and bootstrap variance estimation procedures. RESULTS: Stigma was perceived by 24.4% of respondents accessing mental health services. The frequency was higher among younger respondents (<55 years), those who were not working, those reporting only fair or poor mental health, and the subset who reported having received a diagnosis of a mental disorder. Sex and education level were not associated with perceived stigma. People with schizophrenia reported stigmatization only slightly more frequently than those with mood and anxiety disorders. CONCLUSIONS: Stigmatization is a common, but not universal, experience among Canadians using services for mental health reasons. Stigmatization was a problem for a sizeable minority of respondents with mood, anxiety, and substance use disorders as well as bipolar and psychotic disorders.

The association between major depression prevalence and sex becomes weaker with age.

BACKGROUND: Women have a higher prevalence of major depressive episodes (MDE) than men, and the annual prevalence of MDE declines with age. Age by sex interactions may occur (a weakening of the sex effect with age), but are easily overlooked since individual studies lack statistical power to detect interactions. The objective of this study was to evaluate age by sex interactions in MDE prevalence. METHODS: In Canada, a series of 10 national surveys conducted between 1996 and 2013 assessed MDE prevalence in respondents over the age of 14. Treating age as a continuous variable, binomial and linear regression was used to model age by sex interactions in each survey. To increase power, the survey-specific interaction coefficients were then pooled using meta-analytic methods. RESULTS: The estimated interaction terms were homogeneous. In the binomial regression model I (2) was 31.2 % and was not statistically significant (Q statistic = 13.1, df = 9, p = 0.159). The pooled estimate (-0.004) was significant (z = 3.13, p = 0.002), indicating that the effect of sex became weaker with increasing age. This resulted in near disappearance of the sex difference in the 75+ age group. This finding was also supported by an examination of age- and sex-specific estimates pooled across the surveys. CONCLUSIONS: The association of MDE prevalence with sex becomes weaker with age. The interaction may reflect biological effect modification. Investigators should test for, and consider inclusion of age by sex interactions in epidemiological analyses of MDE prevalence.

Depression and painful conditions: patterns of association with health status and health utility ratings in the general population.

PURPOSE: Preference-weighted HRQoL (utility) ratings are increasingly used to guide clinical and resource allocation decisions, but their performance has not always been adequately explored. We sought to examine patterns of health utility ratings in community populations with depressive disorders and painful conditions. METHODS: We used two Canadian cross-sectional health surveys that obtained Comprehensive Health Status Measurement System/Health Utilities Index Mark 3 (HUI3) ratings and identified people with painful conditions and major depression. We estimated the frequency of item endorsements and mean utility ratings in these groups. RESULTS: Interesting differences between health state ratings and diagnostic categories were noted. For example, 71% of those professionally diagnosed with migraine reported that they usually have "no pain." Despite this, utility ratings were lower in those respondents with depressive episodes and in those with painful conditions. Greater than additive reductions in HUI3 scores were noted in most instances where both depressive disorders and painful conditions were present. CONCLUSIONS: Health utility ratings confirm the clinical impression that painful conditions and depressive disorders magnify each other's impact. Despite weak alignment between the health state definitions incorporated into utility ratings and the diagnostic concepts examined, the HUI3 appeared to capture HRQoL decrements and negative synergies associated with the co-occurrence of depressive episodes and painful conditions.

Health status, stress and life satisfaction in a community population with MS.

BACKGROUND: Community-based studies can describe health status and related variables in people with Multiple Sclerosis (MS) while avoiding biases introduced by help-seeking in specific clinical settings. OBJECTIVE: To describe general health status, stress perceptions and life satisfaction in people with MS, in comparison to those with other types of disabilities. MATERIALS & METHODS: The Participation and Activity Limitation Survey (PALS) was a post-censual survey conducted by Statistics Canada in association with the 2006 Canadian Census. PALS collected data from a random sample of n = 22,513 respondents identified as having health-related impairments. Frequencies and quartiles as well as mean values, along with associated 95% confidence intervals, were calculated in the analysis. RESULTS: PALS identified 245 individuals with MS. Health status, both perceived and when weighted for societal preference, was markedly lower than that of other disabled groups. No differences in self-perceived stress were seen. People with MS reported lower levels of satisfaction with their health but slightly higher levels of satisfaction with their family and friends. CONCLUSIONS: People with MS report lower levels of general health status and more impairment than those with other disabling conditions. Higher levels of satisfaction with friends and family may reflect psychological adaptation to the illness.

Recall of recent and more remote depressive episodes in a prospective cohort study.

BACKGROUND: In psychiatric epidemiology, symptoms are often assessed retrospectively. This raises concerns about the accuracy of the information recalled. In this study, we sought to examine the level of agreement between survey items assessing recent and more remote depressive episodes. METHODS: Data from the Canadian National Population Health Survey (NPHS) were used. The NPHS is a prospective study following a representative cohort of household residents sampled in 1994 and 1995. Every 2 years, participants are administered the Composite International Diagnostic Interview Short Form for Major Depression (CIDI-SFMD). The 2004 NPHS interview also included items asking about past episodes of depression and diagnoses of depression done by health professionals. We used cross-tabulation and logistic regression to explore the relationship between these responses. RESULTS: Approximately, 90% of respondents with CIDI-SFMD-defined major depressive episodes in the year preceding the 2004 interview also reported lifetime episodes or professional diagnoses of depression in 2004. However, responses to the 2004 lifetime items corresponded less closely to CIDI-SFMD results from the same individuals earlier in the longitudinal survey. Only 40.8% of respondents having the most recently identified episode in 1994 subsequently affirmed a past episode of depression in 2004. CONCLUSIONS: Reporting of depressive episodes diminishes with time, suggesting that retrospective assessment of such episodes may be vulnerable to inaccuracy.

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.

Pharmacoepidemiology of benzodiazepine and sedative-hypnotic use in a Canadian general population cohort during 12 years of follow-up.

OBJECTIVE: benzodiazepines (BDZs) and similar sedative-hypnotics (SSHs) can have both beneficial and adverse effects. Clinical practice guidelines indicate that the course of treatment should usually be brief (a few weeks), but patients often take these medications for longer periods of time. We hypothesized that treatment with antidepressants (ADs) would be associated with a shorter duration of SSHs use as mood and anxiety disorders may underlie the symptoms usually targeted by BDZ treatment. METHOD: our study used data from a Canadian longitudinal general health study, the National Population Health Survey, which has collected data since 1994. Data are currently available to 2006. At each interview, all medications taken in the preceding 2 days are recorded. In our study, we used proportional hazard models to describe patterns of initiation and discontinuation of these medications in the general population. RESULTS: at each interview, the frequency of BDZ-SSH use was 2% to 3%. About 1% of the population initiated use in each 2-year follow-up period. Contrary to expectation, taking ADs predicted initiation of BDZ-SSHs, but not discontinuation. CONCLUSIONS: unexpectedly, respondents taking ADs had a higher frequency of new BDZ-SSH use. AD use may be a marker for depression severity or comorbidity, such that the observed results may be an artifact of confounding by these factors. Irrespective of etiology, initiation of AD treatment does not appear to negate the risk of long-term BDZ-SSH use.

Major depression and injury risk.

OBJECTIVE: Cross-sectional epidemiologic studies have inconsistently reported associations between injuries and depressive symptoms. The significance of these findings remains unclear. Major depressive episodes (MDEs) may increase the risk of injury and injuries may increase the risk of MDEs. Longitudinal data are needed to distinguish between these possibilities. METHOD: Data from the Canadian National Population Health Survey (NPHS) were used in this analysis. The NPHS is a prospective study based on a representative sample of household residents in Canada. Injuries were evaluated using self-report items. MDE was assessed using the Composite International Diagnostic Interview-Short Form for major depression. RESULTS: During each round of interviews, an association between MDE and injuries was evident. In longitudinal analyses a bidirectional association was found. MDEs increased the risk of injury (adjusted hazard ratio [HR] 1.6, 95% CI 1.3 to 2.0) and injury increased the risk of MDEs (adjusted HR 1.4, 95% CI 1.1 to 1.8). CONCLUSIONS: Injury prevention efforts may benefit from consideration of MDE as an injury determinant. For example, particular occupational or recreational activities may have a higher risk of injury during depressive episodes. Improved access to mental health resources in clinical settings where injuries are treated may also be valuable. However, additional studies are necessary to confirm these observations and to develop evidence-based interventions.

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.

Frequency of antidepressant use in relation to recent and past major depressive episodes.

OBJECTIVE: There has been a trend toward increasing antidepressant (AD) use in recent decades. We used data from the National Population Health Survey (NPHS) to determine whether this trend is continuing and to provide updated estimates of the frequency of use. METHODS: The NPHS is a longitudinal general health survey that began collecting data in 1994. The NPHS evaluates past-year major depressive episodes (MDEs) using a brief diagnostic instrument. At each biannual interview (from 1994 to 2006) current medication use is recorded. We estimated the frequency with which ADs were taken by respondents (aged 12 years and older) with and without past-year MDEs. These frequencies were cross-tabulated by sex, year of interview, and the reported duration of symptoms. RESULTS: ADs are taken by about 5.4% of the household population at any point in time. Most respondents taking ADs did not report past-year MDEs but 63.9% of respondents taking ADs in the absence of past-year episodes reported previous episodes or being diagnosed by a health professional with depression. This pattern is consistent with long-term treatment for relapse prevention. The overall frequency of use of ADs is increasing only in respondents without past-year episodes. CONCLUSIONS: AD use among community residents with past-year MDEs is no longer increasing. The continued increase in the overall frequency of use may point toward broadening indications for AD treatment and may indicate that people are taking these medications for longer periods of time.

Reciprocal effects of social support in major depression epidemiology.

BACKGROUND: The clinical course and epidemiology of major depressive episodes (MDEs) may be influenced by reciprocal interactions between an individual and the social environment. Epidemiological data concerning these interactions may assist with anticipating the clinical needs of depressed patients. METHODS: The data source for this study was a Canadian longitudinal study, the National Population Health Survey (NPHS), which provided 8 years of follow-up data. The NPHS interview included a brief diagnostic indicator for MDE, the Composite International Diagnostic Interview Short Form for Major Depression (CIDI-SFMD). The NPHS interview also incorporated the Medical Outcomes Study Social Support Scale (MOSSS) and a set of relevant demographic and health-related measures. The MOSSS assesses total social support and four specific dimensions of social support. Hazard ratios (HR) were used to quantify associations in the longitudinal data. RESULTS: LOWER QUARTILE TOTAL SOCIAL SUPPORT RATINGS PREDICTED MDE INCIDENCE: the HR adjusted for age and sex was 1.9 (95% CI 1.6 - 2.2). Lower quartile ratings in specific social support dimensions yielded similar HRs. MDE was associated with emergence of lower-quartile affection social support (age and sex adjusted HR 1.3, 95% CI 1.1 - 1.7), but other aspects of social support were not consistently associated with MDE. CONCLUSIONS: Low social support appears to be a robust risk factor for MDE and can be used to identify persons at higher risk of MDE. Evidence that MDE has a negative effect on social support was weaker and was restricted to affection social support.

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.

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 > or =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 relationship between major depression and marital disruption is bidirectional.

BACKGROUND: Marital status is important to the epidemiology of psychiatric disorders. In particular, the high prevalence of major depression in individuals with separated, divorced, or widowed status has been well documented. However, the literature is divided as to whether marital disruption results in major depression and/or vise versa. We examined whether major depression influences changes of marital status, and, conversely, whether marital status influences the incidence of this disorder. METHODS: We employed data from the longitudinal Canadian National Population Health Survey (1994-2004), and proportional hazards models with time-varying covariates. RESULTS: Major depression had no effect on the proportion of individuals who changed from single to common-law, single to married, or common-law to married status. In contrast, exposure to depression doubled the proportion of transitions from common-law or married to separated or divorced status (HR=2.0; 95% CI 1.4-2.9 P<0.001). Conversely an increased proportion of nondepressed individuals with separated or divorced status subsequently experienced major depression (hazard ratio, HR=1.3; 95% CI 1.0-1.5 P=0.04). CONCLUSION: The high prevalence of major depression in separated or divorced individuals is due to both an increased risk of marital disruption in those with major depression, and also to the higher risk of this disorder in those with divorced or separated marital status. Thus a clinically significant interplay exists between major depression and marital status. Clinicians should be aware of the deleterious impact of major depression on marital relationships. Proactive management of marital problems in clinical settings may help minimize the psycho-social "scar" that is sometimes associated with this disorder.

Prospective evaluation of the effect of major depression on working status in a population sample.

OBJECTIVE: Numerous surveys have reported associations between major depressive episodes (MDEs) and occupational status, but cross-sectional studies cannot quantify the risks of employment transitions nor clarify their temporal direction. The goal of our study was to estimate the impact of MDE on subsequent employment status in a longitudinal community cohort. METHODS: Data from the National Population Health Survey (NPHS) were used. Proportional hazard models and logistic regression were employed to evaluate the effect of MDE on working status during the 1994 to 2004 interval among respondents who reported working at a job or business at baseline. RESULTS: MDE was associated with an increased risk of movement to nonworking status. People aged 26 to 45 years with MDEs have more than double the risk of this transition (HR = 2.6; 95% CI 1.8 to 3.6, P < 0.001). The probability of transition to nonworking status was higher, but the relative effect was smaller in people aged 46 to 65 years (HR = 1.2; 95% CI 0.7 to 2.0, P = 0.47). Retirement or perceived lack of availability of work did not contribute to the association. CONCLUSIONS: MDE is associated with an elevated risk of transition from working to nonworking status, especially in people aged 26 to 45 years.