The yield from national surveys of mental health

Psychiatric epidemiology now: some achievements and prospects

AIMS

It is timely to ask what epidemiology has brought to our knowledge about mental illness and what information is proving of particular value. In this task, the first step is to identify the truly fundamental questions that the epidemiology of mental disorders should be expected to answer. This review is selectively directed at four such questions.

METHODS

A small number of significant publications were identified.

RESULTS

The extent to which some major questions in epidemiology have been answered is examined.

CONCLUSIONS

When considered alongside epidemiological knowledge elsewhere in medicine, psychiatric epidemiology has indisputably proved to be a powerful tool. Descriptive studies have been particularly useful for advocacy and policy, while analytic studies of aetiology have yielded some valuable clues. There are now signs that linkage with neuroscience will bring further progress in understanding the causes of mental disorders.

Changes in the prevalence of major depression in an Australian community sample between 1998 and 2008

OBJECTIVE

To identify changes in the prevalence of major depression between 1998, 2004 and 2008 in South Australia.

METHODS

Face-to-face Health Omnibus surveys were conducted in 1998, 2004 and 2008 with approximately 3000 participants aged 15 years and over, who were random and representative samples of the South Australian population. Each survey used the same methodology. Outcome measures were: major depression as detected by the Mood module of the Primary Care Evaluation of Mental Disorders instrument; mental health literacy by recognition and exposure to classical symptoms of depression; and health status using the SF-36 Physical and Mental Component summaries.

RESULTS

There was a significant increase in the prevalence of major depression from 6.8% (95%CI: 5.9%-7.7%) to 10.3% (95%CI: 9.2%-11.4%; χ² 24.59, p < 0.001) between 1998 and 2008. Significant increases were observed in males aged 15-29 and females aged 30-49 years. There was no significant increase in any other sub-group. The strongest predictor of major depression was health status. Participants with poor/fair mental health literacy were 37% less likely to be classified with major depression.

CONCLUSIONS

The prevalence of major depression increased significantly in South Australia over the last decade and there was a reduction in mental health status and an increase in persons reporting poor health. Unexpectedly, having poor or fair mental health literacy was significantly protective for major depression. Ideally, public health initiatives should result in an improvement in health, but this did not appear to have occurred here.

The epidemiology of depression in metropolitan China

BACKGROUND

Previous surveys on depression in China focused on prevalence estimates without providing a detailed epidemiological profile.

METHOD

Face-to-face household interviews were conducted with a multi-stage household probability sample of 2633 adults (age > or = 18 years) in Beijing and 2568 in Shanghai between November 2001 and February 2002. The World Health Organization Composite International Diagnostic Interview (CIDI) was used to assess major depressive episode (MDE) according to Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV criteria.

RESULTS

The lifetime prevalence and 1-year prevalence estimates of DSM-IV/CIDI MDE were 3.6% [95% confidence interval (CI) 2.8-4.4%] and 1.8% (95% CI 1.2-2.4%) respectively. No significant gender difference was found in these estimates. Respondents born in 1967 or later were at elevated lifetime risk compared with respondents born in earlier cohorts. The mean age of onset was 30.3 years. Among those reporting 1-year MDE, 15.7, 51.8, 25.3 and 6.4% reported mild, moderate, severe and very severe symptoms respectively; 4.8, 2.6 and 3.2% reported suicidal ideation, plans, and recent attempts in the same year respectively. Respondents with 1-year MDE reported a mean of 27.5 days out of role owing to their depression in the year before interview. Significant co-morbidity was found between MDE and other mental disorders [odds ratio (OR) 22.0] and chronic physical disorders (OR 3.2). Only 22.7% of respondents with 1-year MDE sought treatment.

CONCLUSIONS

The low prevalence and insignificant gender difference, but not patterns of onset, course, co-morbidity, and impairment, distinguish the epidemiological profile of MDE in metropolitan China from those in other countries.

The challenges of purpose in the face of chaos: commentary paper by Professor Beverley Raphael

This paper addresses the issues and purposes of psychiatric research into disaster. Purposes include those that are focused on basic scientific questions, such as the role of disaster stressors in contributing to the development of psychiatric morbidity, and research attempting to identify the level of mental health need. There is also intervention research but this is limited in the acute emergency and longer term. These questions and the methodologies to address them, overlap significantly. Many studies use different measures of exposure, disorder and other disaster variables. There is also a wide range of population groups studied, making comparison of findings difficult. Thus, for these large scale events affecting populations, studies may not readily meet either the purposes of affected populations or government funders. Nor are interventions systematically operationalized to promoted replication. Challenges lie in the diversity of researchers, the pluralistic nature of Western society and the rapid development of the field. It is suggested that a set of disaster mental health research standards, based on core principles and data, would facilitate national and international collaboration and the interests of individual researcher. This could lead to comparable studies that could progress the field, while at the same time fostering innovations which could link to these research programmes. Strategic partnerships with government and other funders, as well as affected communities, could strengthen advocacy and commitment for disaster mental health research.