ABSTRACT
A longitudinal study of a general population in Atlantic Canada provided information on associations between two broad categories of illness: somatic disorders and disorders involving depression and/or anxiety. Prevalence was investigated in a sample of 1,003 adults selected in 1952 and another sample of 1,094 adults selected in 1970. Using a cohort of 618 survivors from the 1952 sample who were followed up in 1968, the authors studied prevalence at the beginning and end of the 16-year period. Incidence was also investigated so that the strength of associations between prior illness of one type and subsequent illness of the other type could be assessed. Data were obtained by interviewing subjects with the same structured schedule at each time of investigation. In prevalence enumerations, psychiatric disorders were found to be significantly associated with somatic disorders. Prior somatic disorder was significantly associated with subsequent incidence of depression and/or anxiety and vice versa. The results did not, however, show one direction of influence ("psyche-to-soma" or "soma-to-psyche") to be markedly stronger than the other. The results mainly support the concept of "generalized vulnerability" and draw attention to the importance of recognizing comorbidity in diagnosis and clinical practice.
Subject(s)
Anxiety Disorders/epidemiology , Depressive Disorder/epidemiology , Adult , Anxiety Disorders/complications , Canada/epidemiology , Comorbidity , Cross-Sectional Studies , Depressive Disorder/complications , Female , Health Status , Health Surveys , Holistic Health , Humans , Incidence , Interview, Psychological , Middle Aged , Prevalence , Prospective Studies , Time FactorsABSTRACT
Longitudinal research in Stirling County, Atlantic Canada, indicated that during the 1950s and 1960s the prevalence of depression was significantly and persistently higher in the "low" socioeconomic status population than at other socioeconomic status levels. Anxiety was found to show a less clear picture. Incidence of depression after the study started was also higher among those who were initially in the low socioeconomic status group, supporting the view that the stress of poverty may be causally related to depression. There was also a trend for prior depression to be associated with subsequent downward social mobility, supporting the view that the concentration of depressed people at the lower end of the social hierarchy may result from handicapping aspects of the illness. Neither of these trends was statistically significant. More striking was evidence that, irrespective of socioeconomic status, depression carried a substantial risk for poor clinical course and outcome. Both depression and poverty tended to be chronic, and, accordingly, their association at the end of the study was influenced by their association at its beginning. The stability of the relationship between poverty and depression warrants the attention of caregivers and policymakers and raises new questions about strategies for the study of causal sequences.
Subject(s)
Anxiety Disorders/epidemiology , Depressive Disorder/epidemiology , Social Class , Adult , Canada/epidemiology , Causality , Cohort Studies , Cross-Sectional Studies , Female , Humans , Male , Poverty , Prospective Studies , Risk Factors , Sex Factors , Social Environment , Social MobilityABSTRACT
A longitudinal investigation of psychiatric epidemiology in a general population (the Stirling County study) has indicated that the incidence of depression and anxiety disorders is low relative to prevalence, because these disorders have long durations. In an average year approximately nine adults among 1,000 experience a first-ever episode of one of these disorders. Incident cases over the course of a 16-year follow-up were more likely to have had premonitory symptoms than to have been asymptomatic at the beginning of the study. Among the relatively small number of people who exhibited the clearest prodromal manifestations, incidence was 20 per 1,000 annually. It might be possible to intervene before such disorders become fully formed and persistent if the precursors are given attention.
Subject(s)
Anxiety Disorders/epidemiology , Depressive Disorder/epidemiology , Adult , Aged , Anxiety Disorders/psychology , Cross-Sectional Studies , Depressive Disorder/psychology , Female , Follow-Up Studies , Humans , Incidence , Interview, Psychological , Male , Middle Aged , Predictive Value of Tests , Risk Factors , Software , United States/epidemiologyABSTRACT
As part of the Stirling County Study (Canada), general physicians were interviewed to identify the psychiatric disorders experienced by a sample of adults selected in 1952. Based on information about vital status gathered 16 years later, we found that those with a psychiatric disorder at the beginning of the study experienced 1.6 times the expected number of deaths. The effect in regard to premature mortality and accidental deaths was particularly strong. Four of six categories of psychiatric diagnoses were significantly associated with mortality. In terms of standardized mortality ratios, depression had the highest and anxiety the lowest risk in this general population. The findings are discussed as providing historical background from the 1950s and 1960s for studying trends.
Subject(s)
Cause of Death , Mental Disorders/mortality , Family Practice , Female , Humans , Longitudinal Studies , Male , Risk FactorsABSTRACT
Prevalence studies in psychiatric epidemiology out-number incidence investigations by a wide margin. This report gives descriptive information about the incidence of depression and anxiety disorders in a general population. Using data gathered in a 16-year follow-up of an adult sample selected as part of the Stirling County Study (Canada), the incidence of these types of disorders was found to be approximately nine cases per 1,000 persons per year. The data suggest that for every man who became ill for the first time with one of these disorders, three women became ill. Incidence tended to be higher among relatively young persons. These incidence rates are consistent with prevalence rates of approximately 10 per cent to 15 per cent for depression and anxiety disorders aggregated together, given an estimated average duration of illness of about 10 years. It is concluded that these incidence rates are fairly realistic in view of evidence that disorders of these types tend to be chronic.
Subject(s)
Anxiety Disorders/epidemiology , Depressive Disorder/epidemiology , Epidemiologic Methods , Adult , Canada , Cross-Sectional Studies , Depressive Disorder/mortality , Female , Humans , Longitudinal Studies , Male , Middle Aged , Risk FactorsABSTRACT
A 16-year prospective study of a general population sample indicates that those who had reported a depression and/or anxiety disorder at baseline experienced 1.5 times the number of deaths expected on the basis of rates for a large reference population. As part of the Stirling County Study (Canada), the information was gathered from 1003 adults through structured interviews and was analyzed by means of a diagnostic computer program. The risk for mortality was assessed using external and internal standards, controlling for the effects of age and sex as well as for the presence of self-reported physical disorders at baseline. Increased risk was found to be significantly associated with affective but not physical disorders and with depression but not generalized anxiety. When this evidence about mortality was combined with information about subsequent psychiatric morbidity among survivors, 82% of those who were depressed at baseline had a poor outcome.
Subject(s)
Anxiety Disorders/diagnosis , Depressive Disorder/diagnosis , Mortality , Adult , Age Factors , Aged , Anxiety Disorders/epidemiology , Canada , Cross-Sectional Studies , Depressive Disorder/epidemiology , Diagnosis, Computer-Assisted , Female , Humans , Male , Middle Aged , Outcome and Process Assessment, Health Care , Prospective Studies , Risk , Sex Factors , United StatesABSTRACT
An assessment of the long-term outcome for depression and anxiety disorders in a general population was made as part of the Stirling County Study. Measuring outcome as a dichotomy between experiencing recurrent episodes or not during a 17-year cohort interval, it was found that 56% of the 'cases' had a poor prognosis. While sex, age and level of severity were not significantly related to outcome, an initial diagnosis of depression was predictive of unfavourable prognosis. Only a few of these 'cases' received psychiatric specialty treatment. Some disorders in the community appear, however, to be as serious as those that come to the attention of psychiatrists.
Subject(s)
Anxiety Disorders/diagnosis , Depressive Disorder/diagnosis , Adaptation, Psychological , Anxiety Disorders/psychology , Depressive Disorder/psychology , Diagnosis, Computer-Assisted , Female , Follow-Up Studies , Humans , Male , Recurrence , SoftwareABSTRACT
A computer programme (DPAX) was constructed for a longitudinal study of psychiatric epidemiology in Stirling County (Canada). It identifies disorders involving the syndromes of depression and anxiety based on responses given in structured questionnaire interviews. The programme follows a diagnostic algorithm that uses criteria for: (1) essential features; (2) number, frequency, and pattern of associated symptoms; (3) impairment; and (4) duration. The programme reproduces case evaluations provided by psychiatrists, as conveyed by a sensitivity of 92% and a specificity of 98%.
Subject(s)
Anxiety Disorders/diagnosis , Depressive Disorder/diagnosis , Diagnosis, Computer-Assisted , Anxiety Disorders/epidemiology , Anxiety Disorders/psychology , Canada , Cross-Sectional Studies , Depressive Disorder/epidemiology , Depressive Disorder/psychology , Follow-Up Studies , Humans , Psychological Tests , Psychometrics , SoftwareABSTRACT
Information about point prevalence of depression and anxiety disorders from two cross-sectional surveys in Stirling County (Canada) indicates that an overall prevalence rate of 12.5% characterized a year close to midcentury and a prevalence rate of 12.7% characterized another year toward the end of the century's third quarter. The stability of the prevalence rates contrasts sharply with the fact that numerous social changes took place over this period of time in this place of study. There were, however, small trends in the distribution of depression and anxiety by sex and age, especially an increased similarity in the overall rates for men and women in the age range of 40 to 69 years. Hypotheses are offered about social circumstances that may have influenced the diminishing difference between the sexes.
