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Background: In the absence of strategies for primary prevention, public health initiatives for major depression have generally focused on secondary and tertiary strategies such as case-finding, public and professional education and disease management. Much emphasis has been placed on low reported rates of antidepressant utilization. In principle, increased rates of treatment utilization should lead to improved mental health status at the population level. However, methods for relating antidepressant utilization to population health status have not been described., Methods: An incidence-prevalence model was developed using data from a Canadian national survey, supplemented by parameter estimates from literature reviews. The lifetime sick-day proportion (LSP) was used to approximate point prevalence., Results: Mathematical simulations using this model produced reasonable approximations of point prevalence for major depression. The model suggests that an improved rate of treatment utilization may not, in itself, lead to substantially reduced prevalence. Reducing the rate of relapse in those with highly recurrent disorders, which can be accomplished by long-term antidepressant treatment, is predicted to have a more substantial impact on population health status., Conclusions: The model presented here offers a framework for describing the impact of antidepressant treatment on population health status. Mathematical models may assist with decision-making and priority setting in the public health sphere, as illustrated by the model presented here, which challenges some commonly held assumptions.

Background: Generally, public health strategies for major depression have focused on case-finding, public and professional education, and disease-management strategies. In principle, increased rates of treatment utilization and improved treatment outcomes should lead to improved mental health at the population level. Progress of this sort, however, has been difficult to confirm., Methods: The National Population Health Survey (NPHS) is a large-scale longitudinal study of a representative sample drawn from the Canadian population. To date, Statistics Canada has released data from 3 NPHS cycles: 1994-1995, 1996-1997, and 1998-1999. Treatment utilization and major depression measures were employed in the NPHS survey, providing a unique source of longitudinal Canadian data. In this study, major depression point prevalence (defined using a predictive instrument for annual major depressive episode [MDE] prevalence and responses from a distress scale) and associated treatment utilization were evaluated over time., Results: Between 1994-1995 and 1995-1996, the proportion of persons with depression receiving antidepressant treatment increased dramatically, from 18.2% (12.3% to 22.1%) in 1994-1995 to 32.6% (23.0% to 42.2%) in 1998-1999. Point prevalence of major depression was 2.4%, 1.8%, and 1.9% in the 3 NPHS iterations., Conclusions: Data from the NPHS suggest public health progress against major depression in Canada. More people with major depression in Canada are receiving treatment, and these changes may have been associated with improved population health status. However, both random variation and extraneous societal factors could account for the observed trends in prevalence. It is impossible to relate changes in utilization directly to population health status using the NPHS data.

Depression is a suspected side effect of treatment with interferon beta1a in MS. However, an association with depression has not been confirmed by rigorous studies. During the SPECTRIMS clinical trial of interferon beta1a (Rebif) in secondary progressive MS, depression ratings were obtained from 365 subjects treated either with interferon beta1a or with placebo. No significant differences between groups emerged during 36 months of follow-up. These data suggest that depression is not a side effect of interferon beta1a.

Objectives: To evaluate the moderating effects of various coping strategies on the association between stressors and the prevalence of major depression in the general population., Methods: Subjects from the Alberta buy-in component of the 1994-1995 National Population Health Survey (NPHS) were included in the analysis (n = 1039). Each subject was asked 8 questions about coping strategies that dealt with unexpected stress from family problems and personal crises. Major depression was measured using the World Health Organization's (WHO) Composite International Diagnostic Interview-Short Form (CIDI-SF) for major depression. The impacts of coping strategies in relation to psychological stressors on the prevalence of major depression were determined by examining interactions between coping and life stress on major depression using logistic regression modelling., Results: No robust impact of coping strategies in relation to various categories of stress evaluated in the NPHS was observed. There was evidence that the use of "pray and seek religious help" and "talks to others about the situations" as coping strategies by women moderated the risk of major depression in the presence of financial stress and relationship stress (with a partner). Using emotional expression as a coping strategy by women might decrease the risk of major depression in the presence of 1 or more recent life events, personal stress, relationship stress (with a partner), and environmental stress., Conclusion: Different coping strategies may have a differential impact on the prevalence of major depression in specific circumstances. These findings may be important both to prevent and to treat depressive disorders.

Objective: To replicate previously reported associations between major depressive episodes (MDEs) and long-term medical conditions in a Canadian community sample., Methods: A sample of 2542 household residents was selected using random digit dialing (RDD). Data were collected by telephone interview. The Composite International Diagnostic Interview (CIDI)-Short Form for major depression (CIDI-SFMD) was used to identify MDEs occurring in the previous 12 months. Long-term medical conditions were identified by self-report., Results: The prevalence of MDE was elevated in those subjects who reported 1 or more long-term medical conditions. The association was not due to confounding by age, sex, social support, or stressful recent life events., Conclusion: This study replicates a previously reported association between depressive disorders and long-term medical conditions. These cross-sectional associations suggest that medical conditions may increase the risk of major depression or that major depression may increase the risk of medical conditions. Alternatively, comorbid medical conditions may influence the duration of depressive episodes, or vice versa. These explanations are not mutually exclusive.

The objective of this study was to investigate the effect of persistent alcohol consumption on the risks of major and minor depression. A retrospective cohort study design was used. The data was derived from a large scale longitudinal national health study (Canadian National Population Health Survey). Depression status was evaluated by using the Composite International Diagnostic Interview-Short Form (CIDI-SF) for major depression. Subjects who did not have major depression at baseline were classified into groups according to the persistence of alcohol consumption during the follow-up period. The incidence of major depression in each group was calculated in men and in women separately and were stratified by age. The same procedures were repeated for minor depression. Women who reported having 5+ drinks on one occasion at least once a month were at an elevated risk of major depression. The same pattern was not observed among men in this analysis. However, no difference was found between the groups in terms of the incidence of minor depression. Frequent heavy alcohol use may be a causal factor for major depression among women. Reducing the frequency and quantities of alcohol consumption may offer an opportunity for prevention of major depression among women., (Copyright 2002 Wiley-Liss, Inc.)

Objective: Two recent randomized double-blind placebo controlled clinical trials of interferon beta-1a in multiple sclerosis have obtained hopelessness ratings using the Beck Hopelessness Scale (BHS). One of these studies, the PRISMS trial, evaluated interferon beta-1a in relapsing remitting multiple sclerosis (RRMS). Another, the SPECTRIMS trial, evaluated the same medication in secondary progressive (SP) MS. The objective of this analysis was to compare levels of hopelessness in persons with RRMS and SPMS, and to describe changes over time in the clinical trial participants., Method: Raw data from each clinical trial was obtained from the sponsor of the trials (Serono). Median BHS ratings, and the proportions at or above the BHS cut-point of 10 were calculated over a two (PRISMS) or three (SPECTRIMS) year period., Results: The analysis included n = 532 clinical trial participants. Ratings of hopelessness were higher in SPMS clinical trial participants (SPECTRIMS) than in the RRMS group (PRISMS) at baseline (Fisher's exact test, p = 0.0035). Furthermore, ratings of hopelessness were higher during follow-up than at baseline, in the SPMS group (McNemar's exact probability,p = 0.0015), but not in the RRMS group (McNemar's exact probability,p = 0.65). Depression was strongly associated with hopelessness in both RRMS (z = 4.13, p < 0.001) and SPMS (z = 5.24, p < 0.001)., Conclusions: Hopelessness is associated with SPMS, and may increase over time in this group. Hopelessness may influence suicide risk in people with MS and may potentially have an impact on coping and quality of life. Additional research is necessary to define the clinical implications of hopelessness in persons with this condition.

Objective: Multiple Sclerosis (MS) is associated with elevated levels of depressive symptoms and an elevated frequency of depressive disorders. Depressive disorders, in general, are associated with substantial direct and indirect economic costs, and have been shown to increase the costs associated with the management of medical conditions in a variety of clinical settings. However, the impact of depressive disorders on costs associated with MS have not been evaluated. The objective of this study was to evaluate this association., Methods: The Composite International Diagnostic Interview (CIDI) was used to identify subjects with major depressive disorder in a sample who had earlier been selected for a broader economic evaluation of the costs associated with MS. Costs were measured in two ways: retrospectively (by questionnaire covering a 2-year period) and prospectively (using a 6-month diary). The proportion of subjects reporting any costs and the proportion exceeding various cost thresholds were calculated in subjects with and without lifetime major depression. These proportions were compared using exact statistical tests and confidence intervals. Non-parametric (rank sum) tests were used to compare median costs., Results: Of 136 subjects, 31 had a lifetime history of major depression. MS-related expenses evaluated retrospectively (e.g., house and vehicle alterations and purchases) did not differ depending on major depression status. In the prospective analysis, subjects with lifetime major depression were more likely to purchase vitamins, herbs, and naturopathic remedies (p < 0.01) and more likely to incur costs associated with utilization of services provided by alternative practitioners (p = 0.04). Other differences (e.g., in mental health care, medical specialists, general practitioner visits) were not observed., Conclusions: Contrary to expectation, this study did not find increased direct medical costs in persons with comorbid major depressive disorder and multiple sclerosis. Persons with comorbid MS and (lifetime) major depression did not incur greater costs or utilize more services. The Canadian health care system is guided by principles of universality and is publicly funded and administered, however, the lack of an impact of major depression on utilization may reflect limited access to services. The lack of an association between costs and major depression may or may not be generalizable to health care systems in other countries.

Data from the Canadian National Population Health Survey (1994-1995) were used to evaluate the associations between work stress and major depression (N = 7,344). Major depression was evaluated using the World Health Organization's Composite International Diagnostic Interview- Short Form. Work stress was measured by a 12-item scale in 6 dimensions. Significant associations between work stress and major depression were found. Gender may alter the type of work stress that is most strongly associated with major depression: psychological demands for men and physical demands for women. Some forms of work stress were more strongly associated with major depression in smokers than in nonsmokers.

Objective: To evaluate cross-sectional associations between depressive episodes and a set of potential biopsychosocial determinants in Calgary, Canada., Methods: Random digit dialling (RDD) was used to select a sample consisting of 2,542 household residents in Calgary. These subjects were interviewed over the telephone using the Composite International Diagnostic Interview (CIDI) short form for major depression, and a questionnaire evaluating a variety of biopsychosocial variables., Results: The prevalence of major depression was associated with biological (family history of major depression, alcohol consumption, street drug use), psychological (ratings of stress, recent life events) and social factors (social support, marital status, income, level of education)., Conclusion: This study confirms that major depression is correlated with a diverse set of potential determinants in community populations, and that the impact of these determinants may differ between different populations. Prospective studies will be needed to further investigate these associations.

Objective: To investigate whether alcohol consumption predicts major depressive disorder episodes (MDEs) in the general population., Method: The respondents without depression (n = 12,290) in the longitudinal cohort of the Canadian National Population Health Survey (NPHS) were classified into cohorts based on any drinking, frequency of drinking, maximum number of drinks on a maximal drinking occasion, and average daily alcohol consumption, based on data collected in the 1994-1995 survey. Major depression frequency 2 years later, in 1996-1997, was evaluated and compared across drinking categories., Results: The respondents who reported any drinking, drinking daily, having more than 5 drinks on a maximal drinking occasion, and having more than 1 drink daily on average, did not have an elevated risk of major depression. A trend in the data suggested that women who reported having more than 5 drinks on a maximal drinking occasion might be at a higher risk of major depression. No evidence of confounding or effect modification by demographic, psychological, and clinical variables was found., Conclusion: In a general population sample, alcohol consumption levels were not associated with major depression. Having more than 5 drinks on a maximal drinking occasion, however, may be associated with an increased risk of major depression among women. Extreme patterns of alcohol consumption, which tend to characterize clinical samples, are associated with depression. These patterns of drinking, however, are relatively uncommon in the general population, and the current analysis may have lacked power to detect these associations.

Objective: To determine the relationships between age, prevalence of major depression and antidepressant treatment in Canadian populations by using data from three health surveys., Background: Major depression is an important disorder, and there is a concern that treatment for it may be underutilized. Age may have an impact on treatment use., Methods: Two of the surveys incorporated into the present analysis were random digit dial telephone surveys, with sample sizes of 2542 subjects and 796 subjects, respectively. The third data source was the National Population Health Survey (n=73,402), which used some face to face and some telephone-based data collection methods. In each of these studies, major depression was evaluated using a short form version of the Composite International Diagnostic Interview for Major Depression. Diagnostic status was evaluated in relation to current use of antidepressant medications, age and other relevant factors. All analyses accounted for unequal selection probabilities and clustering inherent in the sampling procedures., Results: The prevalence of major depression was consistently found to be highest in subjects under the age of 45 years. However, older subjects were more likely to report having depression diagnosed. Antidepressant treatment was found to be less frequent in young subjects, despite these subjects being in the group with the highest prevalence of depression. Younger respondents were less likely to see a physician about their depressive symptoms, and when they did they were less likely to be told that they had a depressive disorder., Conclusions: The data presented indicate that antidepressant medications tend to be used less frequently in younger than older age groups in Canada. Additional studies are needed to confirm optimal use rates in relation to age.

Objective: To describe the use of alternative medicine (AM) by persons with major depression and to examine the factors associated with AM use among these individuals., Methods: We used data from the 1994-1995 and 1996-1997 National Population Health Surveys. We selected subjects who had major depression according to the Composite International Diagnostic Interview Short Form for Major Depression (CIDI-SFMD). The prevalence of AM and conventional health service use by the subjects was calculated for each survey and was stratified by province. We employed logistic regression to examine the factors associated with AM use., Results: There was a temporal trend toward increasing use of AM among persons with major depression. The prevalence of AM use among subjects with major depression was 7.8% in 1994-1995 and 12.9% in 1996-1997. Female sex, having more than 12 years' education, and having 1 or more long-term medical conditions were associated with an increased likelihood of using AM. The sex difference in AM use depended on subjects' age in 1996-1997., Conclusion: General practitioners, mental health specialists, and AM providers should be aware of their patients' use of both conventional medical services and AM because there may be interactions between conventional and alternative treatments. Communication and, if possible, cooperation may lead to improved outcomes in the management of depressive disorders.

Depression is a suspected side effect of multiple sclerosis (MS) treatment with interferon beta-1a. However, this has not been confirmed by rigorous studies. Several psychological symptom rating scales were completed during the PRISMS clinical trial of subcutaneous interferon beta-1a (Rebif) for relapsing-remitting MS. We conducted an analysis of these data in order to determine whether symptom elevations were associated with treatment. The PRISMS clinical trial included 560 subjects from 22 centres in nine countries. There were two active treatment arms (44 mcg x 3 and 22 mcg x 3 subcutaneously three times per week) and a placebo group. Two hundred and sixty-seven of these subjects were enrolled at English speaking study centres, where psychiatric symptom ratings were obtained at baseline, 6, 12, 18 and 24 months using the Center for Epidemiological Studies Depression Rating Scale (CES-D), the General Health Questionnaire (GHQ) and the Beck Hopelessness Scale (BHS). After randomization, the groups completing these scales were similar in terms of age, gender, EDSS, duration of illness and employment status. Median CES-D scores in the high dose, low dose and placebo groups at baseline were also similar: 8.0, 7.0 and 8.0, respectively. After 6 months of treatment the median change in CES-D score was zero in all three groups. The proportion of subjects exceeding the traditional CES-D cut-point for clinically significant depression (> 15) after 6 months of treatment was strongly associated with pre-treatment depression (RR 2.9, 95% C.I.: 1.8-4.7), but not with treatment group (chi-square=1.64, d.f.=2, P=0.44). The results were comparable at 12, 18 and 24 months and when ratings from the other scales were evaluated. This analysis confirms that depression is common in persons with MS: the incidence of CES-D depression in the first 6 months of follow-up was 15.6%. However, no evidence of increased depressive symptomatology was observed in association with interferon beta-1a (Rebif).

Objective: To evaluate epidemiological associations between self-reported diet pill consumption and major depressive episodes (MDEs), using data from a large-scale, cross-sectional survey of the Canadian population., Methods: Data from the National Population Health Survey (NPHS) were used in this analysis. The NPHS interview included a brief version of the Composite International Diagnostic Interview (CIDI) depression section, known as the CIDI Short Form for Major Depression (CIDI-SFMD), as well as provision for self-reported medication use., Results: Approximately 0.5% of the population reported the use of diet pills. Diet pill use was more common among women than among men. At the time of data collection (1996-1997), the most commonly used medication was fenfluramine (since withdrawn from the market because of cardiovascular toxicity). The use of these medications was strongly associated with MDE: the annual prevalence among persons reporting use was 17.1% (95% CI, 8.6 to 25.6), approximately 4 times the underlying population rate., Conclusions: Because the NPHS was a general health survey, and because self-reported exposure to these medications was relatively uncommon, the data did not permit a detailed multivariate analysis. These findings, however, indicate that depressive psychopathology is strongly associated with the use of appetite-suppressant medications.

Objective: To evaluate the impact of major depression on alcohol use in the Canadian general population., Method: This study was based on a 2-year follow-up of the Canadian National Population Health Survey (NPHS) longitudinal cohort. Subjects reporting various patterns of drinking, with and without major depression, were selected using the 1994-95 NPHS data. Data collected during a reevaluation of these subjects 2 years later were analyzed to determine whether having major depression at the 1994-95 interview predicted subsequent changes in drinking patterns., Results: Subjects who were depressed in 1994-95 were generally not at higher risk of starting drinking or drinking more frequently than once a week. However, women who were depressed, especially those who were 19 years old or older, were at higher risk of having 5 or more drinks at least once monthly., Conclusion: These results confirm that mood disorders can impact on alcohol consumption in women. A component of the well-known association between alcohol consumption and major depression is due to "reverse" causal effects. Proper management of depression in women may contribute to the prevention of problem drinking.

Objective: To investigate the clinical and pharmacoepidemiological determinants of delirium in a psychiatric inpatient population., Method: A case-control study design was used. Potential cases and potential controls were identified using hospital discharge data. The clinical record of each subject was reviewed using a validated protocol to confirm case and control status. Subsequently, exposure data were recorded from clinical records., Results: Subjects admitted to hospital with delirium tended to be older, to have pre-existing cognitive deficits, and to have diagnoses of substance use disorders. Subjects who developed delirium after their admission to hospital were older than control subjects, more likely to have a history of cognitive impairment, and were significantly more likely to be treated during the hospitalization with lithium or anticholinergic antiparkinsonian medications. Antipsychotic medication exposures were also associated with delirium, but only at standard or above-standard dosage levels. Antidepressant and sedative-hypnotic medications were not associated with delirium., Conclusions: These findings indicate that using conservative dosages of antipsychotic medications and minimizing the use of anticholinergic medications for parkinsonian symptoms may help to prevent delirium in psychiatric inpatients. Anticonvulsant mood stabilizers may convey less delirium risk than lithium. Antidepressant medications and sedative-hypnotics were not important determinants of delirium in this population.

A variety of medications have been reported to cause depression as a side effect. This study evaluated cross-sectional associations between a variety of medications and a syndrome resembling major depression. A sample of 2,542 subjects were selected using the Mitofsky-Waksberg random digit dialing (RDD) procedure. Major depression was evaluated using a short form version of the Composite International Diagnostic Interview (CIDI). Current medication use was recorded during the same telephone interview. Statistical methods accounting for clustering and unequal selection probabilities were employed. Most medications were not associated with major depression: these included beta-blockers, angiotensin-converting enzyme (ACE) inhibitors, lipid-lowering agents, digoxin, and diuretics. Calcium channel blockers were significantly associated with major depression, but only in a subset of young subjects, and these tended to be seriously ill individuals taking multiple medications. Opiate analgesics were associated with major depression, but only in male subjects. Corticosteroids were significantly associated with major depression in a logistic regression model that adjusted for age and gender. The cross-sectional nature of this study precludes causal inference about the observed associations. With the exception of the association of major depression with corticosteroid use, convincing associations with other medications were not observed. It is possible that medication-induced depressive episodes lead to changes in exposure status (such as discontinuation of the offending medications) such that the associations are not apparent in cross-sectional data. If this interpretation is correct, these data suggest that the problem of medication-induced depression is being managed effectively at the clinical level and is not a substantial public health problem., (Copyright 2001 by W.B. Saunders Company)

Background: Cross-sectional studies have reported that certain long-term medical conditions are associated with major depression. Here, these associations are explored using a longitudinal analysis., Methods: Data from the first (1994/95) and second (1996/97) waves of the Canadian National Population Health Survey (NPHS) were utilized. The first wave of the NPHS utilized a probability sample of 17626 members of the Canadian population. Members of this cohort were recontacted by Statistics Canada 2 years later. The Composite International Diagnostic Interview Short Form for Major Depression was used to identify episodes of major depression in both waves of the survey. Subjects free of major depression in the year preceding the 1994/95 survey were selected for inclusion in this analysis. The incidence of new-onset episodes in subjects with and without reported long-term medical conditions was compared., Results: Individuals suffering from one or more long-term medical conditions were found to be at increased risk of major depression. Migraine headaches, sinusitis and back problems were the conditions most strongly associated with major depression. Having a long-term medical condition approximately doubled the risk of major depression in this analysis., Limitations: The most important limitation of this study was its reliance on self report data about medical conditions., Conclusions: A large proportion of the general population in Canada suffers from long-term medical conditions. These individuals are at increased risk of major depression. This study suggests an important role for long-term medical conditions in the etiology of major depression.

Objective: An existing literature suggests that corticosteroid exposures are associated with an elevated level of depressive symptoms in various clinical populations. The objective of this study was to evaluate this association in a general population sample., Methods: Data from a large-scale Canadian health survey were used in this analysis. The survey sample included 73,402 subjects over the age of 12 from the general Canadian population. The survey interview included a short-form version of the Composite International Diagnostic Interview (CIDI) section evaluating major depressive episodes. All estimates were weighted to account for unequal selection probabilities, and variance estimates were calculated using methods accounting for the survey design., Results: A statistically significant elevation in major depression prevalence was observed in corticosteroid-treated subjects. The estimated 12-month period prevalence of major depression was approximately three times as high in corticosteroid treated vs. non-treated subjects irrespective of age, gender and perceived health., Conclusions: In the general population, persons taking corticosteroids have a higher frequency of major depression than non-exposed subjects. Because this was an analysis of cross-sectional survey data, causal inference is not possible. However, the existence of an epidemiological association, in conjunction with information from the broader literature, suggests that corticosteroid exposure may be a determinant of depressive disorders in the general population.

Objective: To estimate the 12-month period prevalence of major depression in Calgary., Methods: Subjects (n = 2542) were selected using random digit dialing (RDD) and interviewed by telephone using the Composite International Diagnostic Interview-Short Form for Major Depression (CIDI-SFMD). A subset of this sample was recontacted and administered the full mood disorders section of the CIDI., Results: The weighted proportion of the sample scoring in the positive range on the major depression predictor was 14.7%. Validation data determined that approximately three-quarters of these subjects would be expected to have major depression according to the CIDI. Hence, the estimated 12-month period prevalence of major depression was approximately 11.0%., Conclusions: This prevalence estimate is higher than most, but not all, previous Canadian estimates and resembles that of the American National Comorbidity Survey (NCS). Calgary may have a high prevalence of major depression; however, because methodologically comparable studies are not available, to conclude this would be premature. Selection bias due to the RDD sampling (and the associated relatively high rate of nonresponse) may have led to an inflated prevalence estimate. Alternatively, because it allows increased anonymity and emotional "distance" from the nonprofessional interviewers, telephone-based data collection may be more sensitive to psychopathology than face-to-face interviewing.

Selection bias may systematically distort estimates deriving from psychiatric studies using clinical subjects. Such bias may impact on cross-sectional studies using samples of convenience and also on clinical case-control studies. The objective of this report is to describe examples of such bias, and to identify probably mechanisms underlying it. A series of cases was recruited from among inpatients at a general hospital in Calgary, Canada. This case-series consisted of consenting subjects with current episodes of major depression according to a structured diagnostic interview. Comparison subjects consisted of non-depressed (according to the structured interview) individuals admitted to the same units and a sample of community subjects scoring negatively on a major depression predictor. Bayesian calculations using ancillary census and national survey data were used to estimate the selection probabilities underlying bias apparent in several of the odds ratio estimates. Neither a cross-sectional analysis incorporating all of the clinical subjects, the use of a community comparison group nor a case-control analysis using a subset of the clinical subjects resulted in valid estimation. This study confirms that the probability of selection of clinical subjects can be conditionally dependent on diagnosis and other variables in ways that create a substantial vulnerability to selection bias.

The objective of this paper was to evaluate the lifetime and point prevalence of major depression in a population-based Multiple Sclerosis (MS) clinic sample, and to describe associations between selected biopsychosocial variables and the prevalence of lifetime major depression in this sample. Subjects who had participated in an earlier study were re-contacted for additional data collection. Eighty-three per cent (n=136) of those eligible consented to participate. Each subject completed the Composite International Diagnostic Interview (CIDI) and an interviewer-administered questionnaire evaluating a series of biopsychosocial variables. The lifetime prevalence of major depression in this sample was 22.8%, somewhat lower than previous estimates in MS clinic populations. Women, those under 35, and those with a family history of major depression had a higher prevalence. Also, subjects reporting high levels of stress and heavy ingestion of caffeine (>400 mg) had a higher prevalence of major depression. As this was a cross-sectional analysis, the direction of causal effect for the observed associations could not be determined. By identifying variables that are associated with lifetime major depression, these data generate hypotheses for future prospective studies. Such studies will be needed to further understand the etiology of depressive disorders in MS.

Some of the variables associated with major depression in community samples may be nonspecific correlates of mental ill-health. The study objective was to evaluate this hypothesis by comparing two groups of psychiatric patients with the general population. Subjects were recruited from psychiatric inpatients at a general hospital in Calgary, Alberta, Canada, by dissemination of a consent form. Consenting subjects completed the mood disorders section of the Composite International Diagnostic Interview (CIDI). All subjects were interviewed to evaluate a set of variables that may be risk factors for major depression. The measurement instruments were identical to those used in a national survey so that comparisons to population-based data were possible. The psychiatric inpatients differed dramatically from community subjects in terms of stress, traumatic life events, recent life events, and social support. However, differences were not observed between inpatients with major depression (according to the CIDI) and inpatients without major depression. Associations between certain variables and major depressive disorders in community populations may reflect nonspecific associations with mental ill-health. This may occur because of nonspecific impacts of these variables on the etiology or prognosis of mental disorders or some nonspecific impact of mental illness itself.

Reports of corticosteroid-induced adverse psychiatric effects began to appear in the literature soon after the introduction of these medications in the 1950s. Unfortunately, early studies relied on informal classification and measurement procedures and tended to utilise nonspecific descriptive terminology (such as steroid psychosis'). A growing number of contemporary investigations have begun to address these problems. However, the literature remains surprisingly undeveloped from a pharmacoepidemiological perspective, consisting largely of case reports and case series. The objective of this review is to summarise published data concerning corticosteroid-induced adverse psychiatric effects. A clinical perspective will be adopted since opportunities to minimise the impact of corticosteroid-induced adverse effects tend to present themselves most readily within the sphere of clinical management. Some of the psychiatric adverse effects of corticosteroids are mild, and not necessarily clinically significant. However, several serious psychiatric syndromes can be caused by corticosteroids: substance-induced mood disorders (with depressive, manic and mixed features), substance-induced psychotic disorders and delirium. While certain clinical groups may be at greater risk of corticosteroid-induced adverse psychiatric effects, corticosteroid-induced psychiatric toxicity is remarkably unpredictable. The literature regarding prevention and treatment of corticosteroid-induced adverse psychiatric effects is poorly developed. As a result, the emphasis of this review is on clinical and epidemiological evidence linking specific adverse effects to corticosteroid medications. However, clinical reports do provide some practical guidance for prevention and treatment, and these are summarised as well. A variety of pharmacological strategies for treatment and prevention have been proposed. Education and support also appear to be important, and perhaps neglected.

Objective: To evaluate the predictive value of dysgraphia and constructional apraxia for delirium among psychiatric inpatients., Method: Data were collected from 2 sources. First, a series of nondelirious psychiatric inpatients that had participated in a previous study was selected to determine the specificity of various indices of dysgraphia and constructional apraxia. Second, a series of 56 psychiatric inpatients with delirium as identified using electronic administrative data and clinical records was selected to evaluate sensitivity., Results: Of the various indices of dysgraphia examined, only a global rating of writing quality and evidence of jagged or angled letter loops were informative clinical signs. The predictive value of constructional apraxia resembled the predictive value of the 2 dysgraphia indices., Conclusions: Dysgraphia and constructional apraxia are useful clinical signs of delirium in the psychiatric inpatient population. Evaluation of these functions can substantially impact diagnostic decisions where diagnostic uncertainty exists. An evaluation of writing and constructional praxis can be easily incorporated into bedside mental status examinations.

Recently, short-form versions of structured psychiatric diagnostic interviews have been developed for epidemiologic and survey research. These short forms can reduce research costs in large-scale studies; however, their accuracy is likely to be less than that of a full diagnostic interview. We evaluated the positive and negative predictive values of a short-form interview derived from the Composite International Diagnostic Interview (CIDI). Samples of subjects who scored both positively (n = 277) and negatively (n = 136) on the CIDI Short Form for Major Depression (CIDI-SFMD) were administered the full depressive disorders section of the CIDI. Almost all subjects who were negative on the short form were similarly classified as not having major depression by the CIDI. Approximately 25% of subjects had false positive results; these subjects tended to be older and less educated than true positives. Approximately 75% of subjects scoring five or more on the CIDI-SFMD had major depression according to the full CIDI, and a proportion of the remainder had less severe depressive syndromes. Some CIDI- SFMD positive subjects may have had depressive symptoms attributable to organic or other etiologies excluded under the definition of major depression.

Objective: To compare the Quality of Life (QOL) of multiple sclerosis (MS) patients with and without lifetime major depression., Method: Data on 136 MS subjects sampled from the University of Calgary MS Clinic were collected. The WHO's Composite International Diagnostic Interview (CIDI) was used to diagnose lifetime major depression. The MSQOL-54 was administered to evaluate QOL of the subjects., Results: Thirty one (22.8 percent) of the 136 MS subjects had lifetime major depression, However, only 6 of these had a current episode at the time of data collection. MS patients with lifetime major depression had significantly lower MSQOL-54 scores in the QOL domains of Energy, Mental Health, Cognitive Function, General Quality of Life, Sexual Function, and Role Limitation-Emotional than the MS patients without lifetime major depression., Conclusions: Lifetime major depression may have a substantial impact on the QOL of people with MS. Alternatively, MS patients with poor QOL may be at greater risk of major depression.

Symptom management is the assessment and treatment of the manifestations of multiple sclerosis (MS). Optimal treatment includes patient education, rehabilitation, counseling, and sometimes medical or surgical therapy. A multi-disciplinary treatment team is usually required to provide the wide range of services necessary to manage MS symptoms. This article will review the medical and surgical options used in the management of primary MS symptoms.

The concept of behavioral contagion implies that certain behaviors may spread through populations in a way analogous to the spread of microbial diseases. If so, mathematical models that are helpful in understanding the spread of infectious diseases may also help to understand the spread of certain behaviors. The objective of this paper was to explore the possibility that the Kermack-McKendrick model of epidemic spread may help to explain the outbreak of riots in crowds. Predictions made by the mathematical model were compared to descriptions of crowd behavior and of police methods for preventing and controlling the outbreak of riots. Many of the predictions made by the model are consistent with published observations about circumstances where riots may occur, and methods useful for controlling them.

The objective of this manuscript is to propose an integrative conceptual model linking depressive disorders and depressive symptoms. Existing conceptual models of depression etiology tend to make this distinction in an arbitrary way. For example, in the current edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV), there is a requirement that severe and persistent depressive symptoms be present for a period of two weeks or more before the depressive syndrome qualifies as a major depressive disorder. The concept of psychosocial stress is a potentially unifying concept relating depressive symptoms to disorders, as stress is a risk factor for both depressive symptoms and depressive disorders. Furthermore, a key feature of the depressive disorders is that they are associated with psychosocial dysfunction, which may be conceptualized as an inability to adapt to environmental stress. The hypothesis presented here is that subclinical depressive symptoms represent an adaptive biological response pattern to psychosocial stress, fostering adaptation in the face of a changing (stressful) environment. However, when a threshold of symptom severity is exceeded, the depressive syndrome becomes maladaptive, impairing adaptation to environmental stress and leading to an accumulation of stressful circumstances and experiences. As such, a vicious cycle may be created, leading, perhaps, to the occurrence of a depressive disorder.

Background: Exogenous corticosteroid exposures are associated with depression in clinical samples, however, the mechanisms underlying this association are unknown. Recent animal studies have shown that corticosteroids enhance conditioning in stressful learning paradigms. It has been hypothesized that corticosteroids may enhance the recollection of stressful experiences in humans, potentially contributing to the etiology of corticosteroid induced depression. This hypothesis has not been evaluated in human subjects., Methods: The first phase of the Canadian National Population Health Survey collected data from a probability sample of 17626 members of the general Canadian population over the age of 12. The data set included measures of drug exposure (including corticosteroid exposures) and childhood and adult psychosocial stressors, including traumatic life events. In this study, self-reported traumatic life events were cross-tabulated against corticosteroid exposures in order to evaluate whether these variables were associated., Results: 52% of subjects treated with corticosteroids in the month prior to the interview, as compared to 41% of non-exposed subjects reported one or more of the following stressors: parental divorce, long term parental unemployment, a "frightening" event that was "thought about for years after", being sent away from home for doing something wrong, parental drug or alcohol abuse, or physical abuse. This difference was statistically significant at the 5% level of confidence., Limitations: The use of cross-sectional survey data in this study precluded confirmation that changes in the pattern of trauma recollection followed exposure to corticosteroids. Also, the study relied on unconfirmed self reported medication exposure data, and ratings from brief survey instruments concerned with life events, stress levels and traumatic experiences., Conclusions: What we report is consistent with, but not confirmatory of, the hypothesis that increased recollection of stressful events may be a mechanism underlying associations between corticosteroids and depression. Additional research is needed in order to determine whether the basis for this association is an altered recollection of life events, or in a differing pattern of life experiences.

Objectives: To evaluate associations between long-term medical conditions and major depression in the Canadian population, and to examine the impact of these conditions on health care service use and disability., Methods: Data from the first wave of the Canadian National Population Health Survey (NPHS) were used. The NPHS used a probability sample of 17,626 Canadians and included questions about long-term medical conditions, health care service use, and disability and a brief predictor of major depression. Contingency tables and graphical techniques were used to evaluate associations between the variables of interest., Results: Various chronic medical conditions were associated with an elevated prevalence of major depression. There was no evidence that subjects with major depression and comorbid medical conditions were more likely to be admitted to hospital or to be high users of physician services. However, major depression comorbid with chronic medical conditions was associated with a greater than expected extent of activity limitations., Conclusions: Chronic illness may increase the risk of depression or the duration of depressive episodes; either effect could lead to an increased prevalence. Alternatively, major depression may predispose individuals to certain chronic illnesses. Comorbid major depression and chronic medical conditions are associated with a considerable burden of disability in the Canadian population but not excessive use of physician services.

Objective: Various clinical studies have documented associations between alcohol consumption and depressive disorders. In some circumstances, alcohol ingestion may cause or worsen depression, whereas in other circumstances the direction of causal effect may be reversed. The objective of this study was to evaluate associations between alcohol consumption and major depression in the Canadian population., Method: Data from the Canadian National Population Health Survey (NPHS) were analyzed. This survey, conducted by Statistics Canada in 1994, used a probability sample of 17,626 subjects. The NPHS included measures of alcohol ingestion and a diagnostic screen for major depression (Composite International Diagnostic Interview [CIDI] Short Form)., Results: Subjects reporting any drinking in the year preceding the interview were more likely to have experienced an episode of major depression during that time than subjects reporting no drinking. Subjects reporting maximal ingestions of 5 or more drinks (and especially 10 or more drinks) on at least 1 occasion during the preceding year were also at greater risk of major depression than nondrinking subjects or subjects reporting smaller maximal ingestions. Neither the average amount consumed daily nor the frequency of drinking was associated with major depression., Conclusions: In the general population, there is no simple relationship between the quantity or frequency of alcohol consumption and the prevalence of major depression. Any drinking and maximal consumption on 1 occasion, however, are related to the prevalence of major depression. Further research is needed to delineate causal mechanisms so that clinical and public-health interventions can be formulated.

Purpose: Recent publications imply the existence of associations between psychotropic drugs use and risk of suicide. Some studies have measured the tissue level of these drugs in suicide deaths, while others compared toxicity indices, defined as number of suicide deaths per million prescriptions for individual antidepressants. Few of these studies used unexposed controls. The objective of this cohort study was to evaluate suicide attempts in subjects recently exposed to benzodiazepines and/or antidepressants, as compared to unexposed controls., Methods: A population of 225,796 persons with prescriptions for benzodiazepines were selected from the Saskatchewan Health Data Bases. Controls consisted of 97,862 individuals who did not receive benzodiazepines., Results: Stratifying the populations into antidepressant users and non-antidepressant users indicated that nonantidepressant users had statistically significant associations between suicide attempts and benzodiazepine use (odds ratio (OR) = 6.2), antipsychotic use, (OR = 2.6), and a history of past treatment for drug/alcohol abuse (OR = 13.4). Antidepressant users showed a statistically significant relation only with past treatment for drug/alcohol use (OR = 5.8). It is argued that the large OR for antidepressant use is due to confounding by indication. If so, the concept of toxicity index is misleading and should not be used., Conclusions: The association between benzodiazepine use and attempted suicide is especially high for nonantidepressant users, for the young, and for males. Whether this relationship is causal or not, physicians should be aware of the high potential for suicide attempts when prescribing benzodiazepines for patients in these high risk groups.

Objectives: To estimate prospectively the incidence of delirium in psychiatric inpatients and to identify risk factors for delirium in this population., Method: The subjects were nondelirious patients newly admitted to the Calgary General Hospital. The Delirium Symptom Interview (DSI), the Confusion Assessment Method (CAM), and the Mini-Mental State Examination (MMSE) were used to identify incident cases of delirium. In order to evaluate the potential impact of selection bias, we conducted a supplementary analysis using record linkage to an electronic administrative data base with coverage of the target population., Results: Of 420 admissions to the hospital, 401 subjects provided informed consent and were not delirious at the time of admission. There were 9 incident cases of delirium. The cumulative incidence rate was, therefore, 2.14 per 100 admissions. The record linkage analysis did not uncover evidence of selection bias. Delirium was associated with a significantly increased length of stay in hospital., Conclusions: Delirium is an uncommon incident event in the psychiatric inpatient population. The incidence rate reported here may be useful as a benchmark for the identification of excessive rates in other inpatient settings. Since delirium is sometimes related to modifiable therapeutic factors, an excessive rate should prompt a search for its causes.

Background: Certain drugs may contribute to the etiology of depressive symptoms and depressive disorders. The objective of this review is to critically appraise the literature concerned with these potential etiological associations., Method: The review was based on papers uncovered in electronic literature searches using Medline, Psychlit and Psychological Abstracts. Statistical power calculations were used to assist in the interpretation of negative results., Results: A large number of publications were uncovered, but most of these were case reports. There were relatively few empirical studies. Corticosteroids, certain calcium channel blockers and digoxin have been associated with depression by replicated, well conducted studies. Psychostimulant withdrawal is also associated with prominent depressive symptoms. Preliminary evidence suggests that antihyperlipidemic agents, angiotensin converting enzyme inhibitors, sedative hypnotics, psychostimulants and certain hormonal agents may also cause depression. Despite an extensive literature, the potential association between beta-blockers and depressive symptoms remains controversial. There is no substantial evidence that l-dopa or histamine-2-receptor blockers cause depression and the literature is relatively conclusive in determining that thiazide diuretics are not associated with depressive symptoms., Conclusions: A small, but growing, literature confirms that certain drug exposures can contribute to the biopsychosocial etiology of depressive symptoms and disorders. Current beliefs and diagnostic conventions classify drug-induced depression into a distinct category (Substance-Induced Mood Disorder): but this approach is not specifically supported by the existing literature.

Background: An association between multiple sclerosis (MS) and depression has been recognized for several decades and has attracted considerable attention in research. However, there are considerable gaps in the current state of knowledge. In this review, the literature concerned with: (1) the burden of depression in MS; (2) the etiology of depression in MS, and (3) the treatment of depression in MS are critically examined., Method: The literature review utilized Medline (1966-1996), and was supplemented by citations extracted from the papers originally uncovered., Results: Numerous studies have identified elevated depressive symptom scores in MS patients relative to nonclinical and (some) clinical control groups. Furthermore, studies of depressive disorders have clearly documented elevated prevalence rates in MS samples. The literature does not identify any specific pattern of neurological involvement as being consistently associated with depressive symptoms or disorders. Psychosocial risk factors contribute to the etiology of depression in MS, but the relative importance of various risk factors is yet to be determined. A single randomized controlled clinical trial, and additional anecdotal evidence, suggests that antidepressant pharmacotherapy is effective for depressive disorders in MS., Conclusions: Future epidemiological studies should not restrict their evaluation of risk factors to those specific factors that are closely related to the disease process. In particular, future researchers should resist the temptation to focus too exclusively on neuropathology. Biological, psychological and social risk factors are all potentially important. Additional empirical efforts to refine the various treatment approaches would be a welcome addition to this literature.

The CIDI Short Form is a brief survey instrument designed to identify episodes of major depression. The instrument was developed for inclusion in the US National Health Interview Survey, but has also been used in the Canadian National Population Health Survey (NPHS). In this study, data deriving from use of the CIDI Short Form in the NPHS are compared to published data from the Mental Health Supplement of the Ontario Health Survey, which utilized a fully validated structured interview: the Composite International Diagnostic Interview (CIDI). In an additional analysis, the sensitivity and specificity of the Short Form were evaluated in relation to the full CIDI mood disorders section in a clinical sample of 122 psychiatric in-patients. Relative to published data from the Ontario Health Survey, application of the CIDI Short Form in the NPHS resulted in an overestimation of major depression prevalence by approximately 50%. In the clinical sample, the CIDI Short Form was highly sensitive (98.4%), but not highly specific (72.7%). Active medical conditions, substance use disorders and dysthymia were frequently observed among subjects with false positive CIDI Short Form ratings. The CIDI Short Form appears to overestimate the 12-month period prevalence of major depression when it is applied in community samples. Since the Short Form does not make exclusions for organically induced symptoms, it is probable that some subjects with depressive symptoms secondary to physical illnesses and/or drug exposures score above the instrument's threshold, perhaps leading to an elevation in period prevalence rates.

Objective: Exposure to certain drugs-angiotensin-converting enzyme inhibitors, beta-blockers, calcium channel blockers, corticosteroids. H2 blockers, and sedative hypnotics-may be associated with an increased risk of depression. These drugs are commonly used in inpatient medical therapeutics. Since population attributable risk (PAR) is generally related both to strength of association and to the frequency of exposure to a risk factor, the PAR of depressive symptoms associated with these drug exposures is potentially high. The objective of this study was to estimate the depressive symptoms population attributable risk percent (PAR%) in a medical inpatient population., Methods: A prospective cohort design was used in this study. Nondepressed, nondrug-exposed subjects (N = 178) were selected from a series of 369 newly admitted medical inpatients at the Calgary General Hospital. Eighty-six of these 178 subjects were prescribed one of the drugs in question, forming an exposed cohort. The remaining subjects formed a nonexposed cohort. Depressive symptoms and associated psychosocial variables were measured in both subgroups during the hospital stay., Results: Seventeen of the 86 exposed subjects and 5 of the 92 nonexposed subjects developed incident depressive symptoms during their stay in hospital. The PAR% associated with drug exposure (56.0%) exceeded that associated with poverty (17.9%) or unemployment (21.7%)., Conclusions: Drug exposures may have a sizeable impact on the incidence of depressive symptoms in medical inpatient populations.

Objective: Certain medications used in cardiovascular therapeutics may contribute to the etiology of substance-induced mood disorders. These medications include digoxin, angiotensin converting enzyme (ACE) inhibitors, beta-blockers, and calcium channel blockers. The objective of this study was to evaluate associations between these drugs and clinical diagnoses of depressive disorders in a population of hospitalized patients., Method: Two case-control studies were conducted. For each study, subjects were selected from a health records data base maintained at the Calgary General Hospital. Selection of subjects in the first study was restricted to those receiving a discharge diagnosis of congestive heart failure and in the second study to subjects receiving a discharge diagnosis of hypertension. In each of these 2 studies, a single case group was selected along with 2 control groups: a psychiatric control group consisting of subjects receiving a psychiatric diagnosis other than a depressive disorder and a nonpsychiatric control group receiving no psychiatric diagnoses. Drug exposures and other variables were recorded from a chart review., Results: Exposures to digoxin, beta-blockers, and calcium channel blockers were not associated with depressive diagnoses. An association was observed, however, for ACE inhibitors. An elevated odds ratio (OR) was observed in each case-control study and was stronger in female subjects and subjects over the age of 65., Conclusions: This is the first reported epidemiological evidence of an association between ACE inhibitors and depressive disorders. The design of this study does not permit a determination of whether the observed association was causal. Additional studies are needed.