Prevalence of seasonal depression in a prospective cohort study.

The prevalence of autumn/winter seasonality in depression has been documented in the longitudinal Zurich cohort study by five comprehensive diagnostic interviews at intervals over more than 20 years (N = 499). Repeated winter major depressive episodes (MDE-unipolar + bipolar) showed a prevalence of 3.44% (5× more women than men), whereas MDE with a single winter episode was much higher (9.96%). A total of 7.52% suffered from autumn/winter seasonality in major and minor depressive mood states. The clinical interviews revealed novel findings: high comorbidity of Social Anxiety Disorder and Agoraphobia within the repeated seasonal MDE group, high incidence of classic diurnal variation of mood (with evening improvement), as well as a high rate of oversensitivity to light, noise, or smell. Nearly twice as many of these individuals as in the other MDE groups manifested the syndrome of atypical depression (DSM-V), which supports the prior description of seasonal affective disorder (SAD) as presenting primarily atypical symptoms (which include hypersomnia and increase in appetite and weight). This long-term database of regular structured interviews provides important confirmation of SAD as a valid diagnosis, predominantly found in women, and with atypical vegetative symptoms.

Childhood adversity and chronicity of mood disorders.

To evaluate the potential impact of early childhood problems on the chronicity of mood disorders. A representative cohort from the population was prospectively studied from ages 19/20 to 39/40. Unipolar (UP) and bipolar disorders (BP) were operationally defined applying broad Zurich criteria for bipolarity. Chronicity required the presence of symptoms for more days than not over 2 years prior to an interview, or almost daily occurrence for 1 year. A family history and a history of childhood problems were taken at ages 27/28 and 29/30. Data include the first of multiple self-assessments with the Symptom-Checklist-90 R at age 19/20, and mastery and self-esteem assessed 1 year later. A factor analysis of childhood problems yielded two factors: family problems and conduct problems. Sexual trauma, which did not load on either factor, and conduct problems were unrelated to chronicity of UP or BP or both together. In contrast, childhood family problems increased the risk of chronicity by a factor of 1.7. An anxious personality in childhood and low self-esteem and mastery in early adulthood were also associated with chronicity. Childhood family problems are strong risk factors for the chronicity of mood disorders (UP and BP). The risk may be mediated partly by anxious personality traits, poor coping and low self-esteem.

Does psychomotor agitation in major depressive episodes indicate bipolarity? Evidence from the Zurich Study.

BACKGROUND: Kraepelin's partial interpretation of agitated depression as a mixed state of "manic-depressive insanity" (including the current concept of bipolar disorder) has recently been the focus of much research. This paper tested whether, how, and to what extent both psychomotor symptoms, agitation and retardation in depression are related to bipolarity and anxiety. METHOD: The prospective Zurich Study assessed psychiatric and somatic syndromes in a community sample of young adults (N = 591) (aged 20 at first interview) by six interviews over 20 years (1979-1999). Psychomotor symptoms of agitation and retardation were assessed by professional interviewers from age 22 to 40 (five interviews) on the basis of the observed and reported behaviour within the interview section on depression. Psychiatric diagnoses were strictly operationalised and, in the case of bipolar-II disorder, were broader than proposed by DSM-IV-TR and ICD-10. As indicators of bipolarity, the association with bipolar disorder, a family history of mania/hypomania/cyclothymia, together with hypomanic and cyclothymic temperament as assessed by the general behavior inventory (GBI) [15], and mood lability (an element of cyclothymic temperament) were used. RESULTS: Agitated and retarded depressive states were equally associated with the indicators of bipolarity and with anxiety. Longitudinally, agitation and retardation were significantly associated with each other (OR = 1.8, 95% CI = 1.0-3.2), and this combined group of major depressives showed stronger associations with bipolarity, with both hypomanic/cyclothymic and depressive temperamental traits, and with anxiety. Among agitated, non-retarded depressives, unipolar mood disorder was even twice as common as bipolar mood disorder. CONCLUSION: Combined agitated and retarded major depressive states are more often bipolar than unipolar, but, in general, agitated depression (with or without retardation) is not more frequently bipolar than retarded depression (with or without agitation), and pure agitated depression is even much less frequently bipolar than unipolar. The findings do not support the hypothesis that agitated depressive syndromes are mixed states. LIMITATIONS: The results are limited to a population up to the age of 40; bipolar-I disorders could not be analysed (small N).

Prevalence, course, and comorbidity of insomnia and depression in young adults.

STUDY OBJECTIVES: (1) To describe the prevalence and prospective course of insomnia in a representative young-adult sample and (2) to describe the cross-sectional and longitudinal associations between insomnia and depression. DESIGN: Longitudinal cohort study. SETTING: Community of Zurich, Switzerland. PARTICIPANTS: Representative stratified population sample. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: The Zurich Study prospectively assessed psychiatric, physical, and sleep symptoms in a community sample of young adults (n=591) with 6 interviews spanning 20 years. We distinguished 4 duration-based subtypes of insomnia: 1-month insomnia associated with significant distress, 2- to 3-week insomnia, recurrent brief insomnia, and occasional brief insomnia. The annual prevalence of 1-month insomnia increased gradually over time, with a cumulative prevalence rate of 20% and a greater than 2-fold risk among women. In 40% of subjects, insomnia developed into more chronic forms over time. Insomnia either with or without comorbid depression was highly stable over time. Insomnia lasting 2 weeks or longer predicted major depressive episodes and major depressive disorder at subsequent interviews; 17% to 50% of subjects with insomnia lasting 2 weeks or longer developed a major depressive episode in a later interview. "Pure" insomnia and "pure" depression were not longitudinally related to each other, whereas insomnia comorbid with depression was longitudinally related to both. CONCLUSIONS: This longitudinal study confirms the persistent nature of insomnia and the increased risk of subsequent depression among individuals with insomnia. The data support a spectrum of insomnia (defined by duration and frequency) comorbid with, rather than secondary to, depression.

Excessive daytime sleepiness in young adults: a 20-year prospective community study.

OBJECTIVE: Excessive daytime sleepiness (EDS) is a symptom with high clinical and public health importance because of its association with increased risk for accidents, decreased productivity, and impaired quality of life. Little information is available regarding the longitudinal course or clinical correlates of EDS. The aim of this study was to explore associations between self-reported EDS, sleep disorder symptoms, major depression, and anxiety in a longitudinal community study of young adults. METHOD: A prospective single-age community study of young adults (Zurich Cohort Study) was conducted from 1978 through 1999. Information was derived from 6 interviews administered when participants (N = 591) were ages 20, 22, 27, 29, 34, and 40 years. Trained health professionals administered a semistructured interview for health habits and psychiatric and medical conditions. The presence of either or both of 2 symptoms-accidentally falling asleep or excessive need for sleep during the day-was used to establish the presence of EDS. RESULTS: EDS was a common complaint among the study participants, with increasing prevalence with age. Cross-sectionally, EDS was associated with insomnia symptoms, nocturnal hypersomnia, anxiety disorders, somatization, and reduced quality of life. Longitudinally, impaired sleep quality, waking up too early, and anxiety were associated with later EDS. Conversely, EDS was not significantly associated with later anxiety or depressive disorders. CONCLUSIONS: Insomnia symptoms and anxiety are associated with the subsequent occurrence of EDS. Although these findings do not demonstrate causality, insomnia and anxiety disorders are prevalent and treatable conditions, and our results may have important clinical implications for the prevention and treatment of EDS. Whether the results of this study are limited to populations with elevated levels of psychopathology remains to be tested.

The association between short sleep duration and obesity in young adults: a 13-year prospective study.

STUDY OBJECTIVES: Obesity has become a major health problem with increasing prevalence. Given the limited availability of effective treatment of weight problems, the identification of potentially modifiable risk factors may lead to preventive approaches to obesity. The objective of this study was to test the hypothesis that short sleep duration is associated with obesity and weight gain during young adulthood. DESIGN: Prospective single-age cohort study of young adults. Information was derived from 4 interviews when participants were ages 27, 29, 34, and 40 years. SETTING: Community setting. PARTICIPANTS: 496 young adults. MEASUREMENTS AND RESULTS: Trained health professionals administered a semistructured interview for psychiatric and medical conditions and health habits. This study showed an association between short sleep duration and obesity (at age 27 years, odds ratio: 7.4, 95% confidence interval: 1.3-43.1) and a negative association between sleep duration and body mass index in young adults. These associations persisted after controlling for a variety of potentially confounding variables, including family history of weight problems, levels of physical activity, and demographic variables. Associations between sleep duration and obesity diminished after age 34 years. There was a trend (P = .08) for average change rate of weight gain to be negatively associated with average change rate of sleep duration. CONCLUSIONS: Because sleep duration is a potentially modifiable risk factor, these findings might have important clinical implications for the prevention and treatment of obesity.

Recurrent brief depression--past and future.

Recurrent brief depressive disorder (RBD) is a well-defined and significantly prevalent affective disorder with an increased risk of suicidal behavior and significant clinical impairment in the community and general practice. RBD is characterized by depressive episodes occurring at least once a month and lasting for only a few days. The lifetime co-occurrence of both RBD and major depressive disorder (MDD), called combined depression (CD), increases substantially the risk for suicide attempts, even more than is known for "pure" MDD. Diagnostic criteria for RBD can be found in the ICD-10 and DSM-IV and are helpful in both, research and clinical routine. Furthermore, several methodological issues are covered in this paper, which make clinical diagnostic and drug response evaluation of RBD very different from MDD. However, clinical procedures rather bear a resemblance to those used in the treatment of migraine or epilepsy. Formal differences in the course of RBD and MDD create different needs concerning the design of drug treatment studies. Absence of special methodological requirements and highly selected patient samples has probably been responsible for false negative results in double-blind, placebo-controlled treatment studies. Although several authors reported successful treatment of RBD with different compounds in about 60 patients, it is still not possible to deduce a treatment algorithm for RBD to date. Obviously, future treatment studies without the limitations of previous studies are clearly required for RBD.

Diagnostic issues in bipolar disorder.

Bipolar disorder is a highly recurrent and chronic psychiatric condition that shortens life expectancy, causes functional impairment and disruption to social, work and family life. Several forms of bipolar disorder are recognised, including both bipolar I and bipolar II disorder. Bipolar I is characterised by recurrent episodes of depression and mania whereas bipolar II disorder is characterised by recurrent depression and hypomania, a milder form of mania. There has been debate concerning the definition of hypomania since at least the 1970s. The main areas of argument focus on the minimum duration of hypomania, its stem criteria and the number of symptoms required for diagnosis. Arriving at the correct definition of hypomania is a key diagnostic issue. There is increasing evidence for the existence of a broad spectrum of bipolar disorders, and data demonstrating the clinical validity of modifying some of the criteria for hypomania are reviewed here.

Toward a re-definition of subthreshold bipolarity: epidemiology and proposed criteria for bipolar-II, minor bipolar disorders and hypomania.

BACKGROUND: The boundaries of bipolarity have been expanding over the past decade. Using a well characterized epidemiologic cohort, in this paper our objectives were: (1). to test the diagnostic criteria of DSM-IV hypomania, (2). to develop and validate criteria for the definition of softer expressions of bipolar-II (BP-II) disorder and hypomania, (3). to demonstrate the prevalence, clinical validity and comorbidity of the entire soft bipolar spectrum. METHODS: Data on the continuum from normal to pathological mood and overactivity, collected from a 20-year prospective community cohort study of young adults, were used. Clinical validity was analysed by family history, course and clinical characteristics, including the association with depression and substance abuse. RESULTS: (1). Just as euphoria and irritability, symptoms of overactivity should be included in the stem criterion of hypomania; episode length should probably not be a criterion for defining hypomania as long as three of seven signs and symptoms are present, and a change in functioning should remain obligatory for a rigorous diagnosis. (2). Below that threshold, 'hypomanic symptoms only' associated with major or mild depression are important indicators of bipolarity. (3). A broad definition of bipolar-II disorder gives a cumulative prevalence rate of 10.9%, compared to 11.4% for broadly defined major depression. A special group of minor bipolar disorder (prevalence 9.4%) was identified, of whom 2.0% were cyclothymic; pure hypomania occurred in 3.3%. The total prevalence of the soft bipolar spectrum was 23.7%, comparable to that (24.6%) for the entire depressive spectrum (including dysthymia, minor and recurrent brief depression). LIMITATION: A national cohort with a larger number of subjects is needed to verify the numerical composition of the softest bipolar subgroups proposed herein. CONCLUSION: The diagnostic criteria of hypomania need revision. On the basis of its demonstrated clinical validity, a broader concept of soft bipolarity is proposed, of which nearly 11% constitutes the spectrum of bipolar disorders proper, and another 13% probably represent the softest expression of bipolarity intermediate between bipolar disorder and normality.

Therapeutic relationship in the context of perceived coercion in a psychiatric population.

The relationship between patient and therapist in mental health care is one of the most important treatment factors. It is a reliable predictor of treatment outcome, regardless of diagnosis, setting or of the type of therapy used. On the other hand, influence and coercion occur in patient-physician relationships in psychiatry. We investigated the associations between patients' perceived coercion and the therapeutic relationship. A total of 116 psychiatric patients, who have been admitted to the Psychiatric University Hospital Zurich, were interviewed using a structured interview. Data were collected by using Scale To Assess the Therapeutic Relationship (STAR) (therapeutic relationship) and Mac Arthur Admission Experience Survey (AES) (perceived coercion). Associations were investigated using bivariate and multivariate methods. Perceived coercion predicts the patients' appraisal of the therapeutic relationship. We found a moderate relation between the patients' and the clinicians' view of their relationship. Perceived coercion is related to a higher symptom level and a lower level of global functioning at admission, and higher perceived coercion is related to a more negative patient-therapist relationship rated by the patient. Perceived loss of autonomy goes hand in hand with a more negative relationship between the patient and the clinician. This phenomenon has to be impeded, regarding the unambiguous impact relationship quality has on treatment outcome.

Long-term depression versus episodic major depression: results from the prospective Zurich study of a community sample.

BACKGROUND: Clinical studies have demonstrated a great clinical relevance of long-term depression (LTD). Our study aims to characterise LTD in comparison with episodic (non-chronic) major depressive episodes (MDE) on the basis of data from a community sample. METHOD: The Zurich Cohort Study is a prospective study of young adults followed from age 20/21 to 40/41 with six interviews. The stratified sample consisted of two thirds high scorers and one third lower scorers on the Symptom Checklist-90 R (SCL-90-R). LTD was assessed from age 27/28 to 40/41 and defined as being symptomatic more days than not over 2 years plus the presence of work impairment. MDE and dysthymia were defined by DSM-III-R criteria. RESULTS: The cumulative incidence of LTD was 5.7%, and of episodic MDE 20.9%. In both groups we found a similar preponderance of women. LTD subjects reported disturbed memory, feelings of inferiority, hopelessness, fear of everyday tasks, fear of being alone and thoughts of dying significantly more often than subjects with episodic MDE. Subjects with LTD had an earlier age of onset. 82% of them were treated over lifetime for depression compared to 61% with MDE. LTD subjects were less often married, less often in fulltime employment, more often unemployed, and more often receiving social benefits. LTD was comorbid with cardiac and respiratory syndromes, and LTD subjects were more frequently treated for insomnia and pain. They suffered significantly more from social phobia and benzodiazepine abuse; there was also a statistical trend to greater comorbidity with panic attacks, agoraphobia, obsessive-compulsive syndrome, binge eating and neurasthenia. Somatic and psychological well-being were also reduced. CONCLUSIONS: LTD is common, clinically more serious than episodic MDE and highly comorbid. LIMITATIONS: The sample is relatively small with an attrition rate of 38.5% over 20 years. The results cannot be generalised to persons over 40 years of age and may be dependent on the definition of LTD.

The spectra of neurasthenia and depression: course, stability and transitions.

BACKGROUND: Neurasthenia has had a chequered history, receiving changing labels such as chronic fatigue or Gulf war syndrome. Neurasthenia is recognized by ICD-10, but not by DSM-IV. Its course, longitudinal stability and relationship to depression is not well understood. METHODS: In a stratified community sample (n = 591), representative of 2600 persons of the canton of Zurich, Switzerland, neurasthenia and depression were assessed in six structured interviews between ages 20 and 41. Course, stability and comorbidity were examined. A severity spectrum of neurasthenia and depression from symptoms to diagnosis was taken into account. RESULTS: The annual prevalence of a neurasthenia diagnosis increased from 0.7% to 3.8% from age 22-41, while mere symptoms became less prevalent. Intraindividual courses improved in 40% and deteriorated in about 30% of symptomatic cases. The most frequent symptoms overall, besides criterial exhaustion, were increased need for sleep, over-sensitivity, nervousness and difficulty concentrating. Cross-sectional associations and overlap with depression were strong. Longitudinal stability of ICD-neurasthenia was low. CONCLUSIONS: Neurasthenia is intermittent, overlaps significantly with depression, and shows improvement and deterioration over time to roughly equal measures.

Varying temporal criteria for generalized anxiety disorder: prevalence and clinical characteristics in a young age cohort.

BACKGROUND: This study questions the 6-month duration criterion for generalized anxiety disorder (GAD) used in DSM-III-R and DSM-IV. METHOD: In adults from age 20/21 to 40/41 in the prospective Zurich Cohort Study, four groups of generalized anxiety syndromes defined by varying duration (2 weeks, 1 month, 3 months and 6 months) were compared. RESULTS: Applying DSM-III (1979-1999) and DSM-III-R (1986-1999) criteria, there were no significant differences between the four groups in terms of family history of anxiety, work impairment, distress, treatment rates or co-morbidity with major depressive episodes (MDEs), bipolar disorder or suicide attempts. Only social impairment related to the length of episodes. The 6-month criterion of DSM-III-R and DSM-IV GAD would preclude this diagnosis in about half of the subjects treated for generalized anxiety syndromes. CONCLUSIONS: In this epidemiological sample, the 6-month duration criterion for GAD could not be confirmed as clinically meaningful. GAD syndromes of varying duration form a continuum with comparable clinical relevance.

Obsessive-compulsive syndromes and disorders: significance of comorbidity with bipolar and anxiety syndromes.

OBJECTIVE: To determine the prevalence and clinical characteristics of comorbid obsessive compulsive disorders and syndromes (OCD/OCS), compared with pure OCD/OCS among adults in the community. METHOD: Data were drawn from the Zurich Study, a longitudinal cohort study of 591 adults in the canton of Zurich. Comorbid OCD/OCS was compared with pure OCD/OCS groups in terms of distress, impairment, family history, suicide behavior and treatment using multivariable logistic regression analyses. RESULTS: OCD was significantly comorbid with bipolar I/II and minor bipolar disorders, anxiety states (GAD, repeated panic attacks) and social phobia, whereas there was no clear association between OCD and major depressive disorder or phobias other than social phobia. Results suggest that comorbid OCD/OCS is common among adults in the community, with the majority of those with OCD/OCS having at least one comorbid mood or anxiety disorder with a prevalence of 7.4% compared to 4.8% of remaining OCD/OCS. Comorbidity of OCD/OCS and anxiety states was more common among women (85.6 %) and comorbidity with bipolar spectrum was more common among men (69.6%). Comorbid OCD/OCS was associated with significantly higher levels of treatment seeking, impairment,distress and suicidality compared with pure OCD/OCS. Comorbidity with bipolar disorders significantly increased the risk for alcohol abuse/dependence. CONCLUSION: Comorbidity of OCD/OCS with bipolar disorder and bipolar spectrum disorders is common and very probably explains the association between OCD and depression found in other studies. The early recognition of bipolar/cyclothymic OCD/OCS may help to prevent the abuse of/dependence on alcohol.

Asthma and panic in young adults: a 20-year prospective community study.

RATIONALE: Psychologic factors are increasingly recognized to influence the onset and course of asthma. Previous cross-sectional community-based studies have provided evidence for a relatively specific association between asthma and panic. OBJECTIVES: To examine concurrent and longitudinal associations between asthma and panic in young adults. MEASUREMENTS AND MAIN RESULTS: Prospective community-based cohort study of young adults (n = 591) followed between ages 19 and 40. Information was derived from six subsequent semistructured diagnostic interviews conducted by professionals. Cross-sectionally (over the whole study period), asthma was more strongly associated with panic disorder (odds ratio [OR] = 4.0; 95% confidence interval [CI], 1.7, 9.3) than with any panic, which included panic disorder and panic attacks (OR = 2.1; 95% CI, 1.1, 4.5). Longitudinally, after adjusting for potentially confounding variables, active asthma predicted subsequent panic disorder (OR = 4.5; 95% CI, 1.1, 20.1), and the presence of panic disorder predicted subsequent asthma activity (OR = 6.3; 95% CI, 2.8, 14.0). Asthma predicted any panic (OR = 2.7; 95% CI, 1.1, 7.1), whereas any panic did not predict subsequent asthma activity. Associations were stronger in smokers than in nonsmokers, and stronger in women than in men. Smoking, early-childhood anxiety, and a family history of allergy were important confounders of the asthma-panic association. CONCLUSIONS: This is the first long-term follow-up study on asthma and panic. It showed dose-response-type relationships between panic and asthma, and bidirectional longitudinal associations between the two conditions. It provided evidence for familial factors and smoking as possible shared etiologic explanations.

Major depression predicts an increase in long-term body weight variability in young adults.

OBJECTIVE: To test the hypothesis that major depression predicts an increase in long-term body weight variability (BWV). RESEARCH METHODS AND PROCEDURES: This was a prospective community-based single-age cohort study of young adults (N = 591) followed between the ages of 19 and 40. Following initial screening, information was derived from six subsequent semistructured diagnostic interviews conducted by mental health professionals. Major depression was diagnosed on the basis of DSM criteria. BWV was defined as the root mean square error of a regression line fitted to each individual's BMI values over time. Multiple regression analysis was used to test the association between major depression and BWV while controlling for potentially confounding variables including antidepressant treatment, eating disorder symptoms, and physical activity. We used random effects models to determine the temporal relationship between repeated measures of major depression and body weight change. RESULTS: A highly significant positive association between major depression and BWV was found, whereas major depression was not associated with BMI level or BMI trend. Depression severity showed a dose-response-type relationship with the magnitude of BWV. After controlling for potentially confounding variables including antidepressant use, eating disorder symptoms, smoking, and physical activity, major depression remained a significant predictor of BWV (beta= 0.13, p < 0.001). Longitudinal analysis revealed a unidirectional association between major depression and a later increase in body weight change rate irrespective of antidepressant medication. DISCUSSION: Results from this study implicate depression as an important risk factor for increased BWV. Given increasing evidence for a link between major depression and both diabetes and cardiovascular disease, current results encourage further research on depression, BWV, and negative health outcomes.

Obsessive-compulsive severity spectrum in the community: prevalence, comorbidity, and course.

OBJECTIVES: To describe lifetime prevalence rates, course and comorbidity of obsessive-compulsive disorder (OCD), obsessive-compulsive syndromes (OCS) and OC-symptoms (OC-sx) up to age 41. METHODS: In the Zurich community cohort study 591 subjects were selected after screening at the age of 19 and studied prospectively by 6 interviews from 20 to 40; they represent 1599 subjects of the normal population. The diagnoses of OCD met DSM-IV criteria. Course was assessed by graphic illustrations and prospective data. RESULTS: The lifetime prevalence rate was 3.5 % for OCD (males 1.7%, females 5.4 %) and 8.7 % for OCS (males 9.9%, females 7.5 %). The onset of OC-sx was 18 years (median); and in 70% before age 20. OCD was treated in one third of cases, OCS in 6.1%. The course of symptoms was chronic in 60%,but OCD and OCS showed in most cases considerable improvements over time. OCD reduced quality of life mostly in the subject's psychological wellbeing and at work but to a considerable extent also in other social roles. Comorbidity was prominent with bipolar disorder, panic disorder and social phobia and also significant with bulimia, binge eating, generalized anxiety disorder and suicide attempts; there was no association with substance abuse/dependence. CONCLUSION: OCD and OCD are manifestations of a wide spectrum of severity with high prevalence and strong clinical validity. The long-term course is better than generally assumed.