Prevalence of and risk factors for suicide-related outcomes in the World Health Organization World Mental Health Surveys Japan

Aim:  Suicide is a major public health concern in Japan but little is known about the prevalence of and risk factors for suicidal ideation, plans, and attempts. The aim of the present study was to clarify the prevalence of and risk factors for important suicide-related outcomes.
Methods:  Important suicide-related outcomes and risk factors were assessed in face-to-face interviews with 2436 adult respondents in seven areas as part of the World Health Organization (WHO) World Mental Health Survey Initiative. Mental disorders were assessed with the WHO Composite International Diagnostic Interview (CIDI).
Results:   The lifetime prevalence estimates of suicidal ideation, plans, and attempts were 10.9%, 2.1%, and 1.9%, respectively. Risk of suicide plans and attempts was highest when suicidal ideation occurred at an early age and within the first year of ideation. In middle-aged individuals, the period after first employment and the presence of mental disorders were risk factors.
Conclusions:  Risk of suicide plans and attempts is highest when suicidal ideation occurred at an earlier age and within the first year of ideation. Mental disorders are as predictive of the suicide-related outcomes examined here, and comorbidity is an important predictor.     

Disability in Te Rau Hinengaro: the New Zealand Mental Health Survey

OBJECTIVE: To show the disability associated with 1 month mental disorders and chronic physical conditions for the New Zealand population, controlling for comorbidity, age and sex. METHOD: A nationally representative face-to-face household survey was carried out from October 2003 to December 2004 with 12,992 participants aged 16 years and over, achieving a response rate of 73.3%. Mental disorders were measured with the World Mental Health (WMH) Survey Initiative version of the Composite International Diagnostic Interview (CIDI 3.0). Disability was measured with the WMH Survey Initiative version of the World Health Organization Disability Assessment Schedule (WMH WHO-DAS) in the long-form subsample (n = 7435). Outcomes include five WMH WHO-DAS domain scores for those with 1 month mental disorders and with chronic physical conditions. RESULTS: Mood disorders were associated with more disability than anxiety or substance use disorders. Experiencing multiple mental disorders was associated with substantial role impairment. Mental disorders and chronic physical conditions were associated with similar degrees of disability on average. The combination of mental and physical disorders had additive effects on associated disability. CONCLUSIONS: Mood disorders are disabling. The investigation of disability in relation to 1 month rather than 12 month disorders is likely to provide a clearer indication of the disability associated with mood disorders. Although some researchers have queried whether negative mood can lead to 'over-reporting' of disability, recent conceptualizations of disability provide a perspective which may ease such concerns. Comorbidity, of mental disorders or of mental and physical disorders, is disabling.     

The impact of comorbidity of mental and physical conditions on role disability in the US adult household population

CONTEXT: There is limited information that accounts for comorbidity on the impact of role disability associated with a wide range of mental and physical disorders in population-based samples. OBJECTIVE: To estimate the comparative effects of common mental and physical conditions on role disability in the general population using a novel method that accounts for comorbidity. DESIGN: Direct interviews about physical and mental conditions during the past year. SETTING: The National Comorbidity Survey Replication, a nationally representative series of face-to-face interviews. PATIENTS: A nationally representative sample of adults living in households (N = 5962 respondents, 18 years and older). MAIN OUTCOME MEASURE: Disability in major life roles was assessed with the World Health Organization Disability Assessment Schedule. Simulations that allow for complex interactions among conditions were used to estimate the conditions' effects on disability days, when respondents were completely unable to carry out their usual daily activities because of problems with mental or physical health, in the past 12 months. RESULTS: An estimated 53.4% of US adults have 1 or more of the mental or physical conditions assessed in the survey. These respondents report an average 32.1 more role-disability days in the past year than demographically matched controls, equivalent to nearly 3.6 billion days of role disability in the population. Musculoskeletal disorders and major depression had the greatest effects on disability days. Mental conditions accounted for more than half as many disability days as all physical conditions at the population level. Associations of specific conditions with disability decreased substantially after controlling for comorbidity, suggesting that prior studies, which generally did not control for comorbidity, overestimated disease-specific effects. CONCLUSION: The staggering amount of health-related disability associated with mental and physical conditions should be considered in establishing priorities for the allocation of health care and research resources.     

Functional disability of mental disorders and comparison with physical disorders: a study among the general population of six European countries

OBJECTIVE: To examine the association of mental and physical disorders with multiple domains of functioning and compare the two. METHOD: Data were derived from the European Study of the Epidemiology of Mental Disorders, a general population study in which adults (n > 21,000) from Belgium, France, Germany, Italy, the Netherlands and Spain were assessed using the Composite International Diagnostic Interview (mental disorders), World Health Organization Disability Assessment Schedule second edition (functional disability) and self-report (physical disorders). Means in different groups were compared using the Mann-Whitney U-test and multiple regression analyses. RESULTS: Mental disorders were related to disability in all domains of functioning: anxiety disorders the most, followed by mood disorders, and finally alcohol disorders. The findings suggest that mental disorders are associated with similar or higher levels of disability in all domains, except getting around, than arthritis and heart disease. CONCLUSION: Mental disorders are associated with a similar or higher negative impact on daily functioning than arthritis and heart disease.     

Comorbid physical health conditions and anxiety disorders: a population-based exploration of prevalence and health outcomes among older adults

ObjectiveThe primary objectives of this study were to examine the likelihood of anxiety disorders among respondents with common physical health conditions and to explore the associations between this comorbidity and older adults' perceived mental and physical health.MethodThe sample consisted of older adults from the Canadian Community Health Survey 1.2 (n=12,792). Trained lay interviewers assessed psychiatric disorders based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria. Physical health conditions were based on self-reported diagnoses by health professionals. Multiple logistic regressions examined whether suffering from a physical health condition increased the odds of any assessed anxiety disorder (panic, agoraphobia, social phobia and posttraumatic stress disorder). Multiple linear regressions examined associations between self-rated health and comorbid physical health conditions and anxiety.ResultsAfter adjusting for confounding variables, the presence of chronically painful conditions (i.e., arthritis, back pain and migraine) and of other commonly occurring diseases (i.e., allergies, cataracts and gastrointestinal, lung and heart disease) were positively associated with anxiety. The comorbidity of anxiety with allergies, cataracts, arthritis and lung disease resulted in poorer self-rated physical and/or mental health after adjusting for confounding variables.ConclusionHealth problems in older adults are associated with increased odds of anxiety, and this comorbidity is associated with poorer self-reported health than medical problems or anxiety alone. These findings have important clinical implications for health professionals.     

Associations between DSM-IV mental disorders and subsequent onset of arthritis

ObjectiveWe investigated the associations between DSM-IV mental disorders and subsequent arthritis onset, with and without mental disorder comorbidity adjustment. We aimed to determine whether specific types of mental disorders and increasing numbers of mental disorders were associated with the onset of arthritis later in life.MethodData were collected using face-to-face household surveys, conducted in 19 countries from different regions of the world (n = 52,095). Lifetime prevalence and age at onset of 16 DSM-IV mental disorders were assessed retrospectively with the World Health Organization (WHO) Composite International Diagnostic Interview (WHO-CIDI). Arthritis was assessed by self-report of lifetime history of arthritis and age at onset. Survival analyses estimated the association of initial onset of mental disorders with subsequent onset of arthritis.ResultsAfter adjusting for comorbidity, the number of mood, anxiety, impulse-control, and substance disorders remained significantly associated with arthritis onset showing odds ratios (ORs) ranging from 1.2 to 1.4. Additionally, the risk of developing arthritis increased as the number of mental disorders increased from one to five or more disorders.ConclusionThis study suggests links between mental disorders and subsequent arthritis onset using a large, multi-country dataset. These associations lend support to the idea that it may be possible to reduce the severity of mental disorder–arthritis comorbidity through early identification and effective treatment of mental disorders.     

Mental-physical comorbidity in Te Rau Hinengaro: the New Zealand Mental Health Survey

OBJECTIVE: To estimate the prevalence of chronic physical conditions, and the risk factors for those conditions, among those with 12 month mental disorder; to estimate the prevalence of 12 month mental disorder among those with chronic physical conditions. METHOD: A nationally representative face-to-face household survey was carried out in October 2003 to December 2004 with 12,992 participants aged 16 years and over, achieving a response rate of 73.3%. Mental disorders were measured with the World Mental Health version of the Composite International Diagnostic Interview (CIDI 3.0). Physical conditions were self-reported. All associations are reported adjusted for age and sex. RESULTS: People with (any) mental disorder, relative to those without mental disorder, had higher prevalences of several chronic physical conditions (chronic pain, cardiovascular disease, high blood pressure and respiratory conditions) and chronic condition risk factors (smoking, overweight/obesity, hazardous alcohol use). Around a quarter of people with chronic physical conditions had a comorbid mental disorder compared with 15% of the population without chronic conditions. Significant relationships occurred between some mental disorders and obesity, cardiovascular disease and diabetes for females, but not for males. CONCLUSIONS: This paper provides evidence of substantial comorbidity between mental disorders and chronic physical conditions in New Zealand. This should be borne in mind by clinicians working in both mental health and medical services.     

Days out of role due to common physical and mental conditions: results from the WHO World Mental Health surveys

Days out of role because of health problems are a major source of lost human capital. We examined the relative importance of commonly occurring physical and mental disorders in accounting for days out of role in 24 countries that participated in the World Health Organization (WHO) World Mental Health (WMH) surveys. Face-to-face interviews were carried out with 62?971 respondents (72.0% pooled response rate). Presence of ten chronic physical disorders and nine mental disorders was assessed for each respondent along with information about the number of days in the past month each respondent reported being totally unable to work or carry out their other normal daily activities because of problems with either physical or mental health. Multiple regression analysis was used to estimate associations of specific conditions and comorbidities with days out of role, controlling by basic socio-demographics (age, gender, employment status and country). Overall, 12.8% of respondents had some day totally out of role, with a median of 51.1 a year. The strongest individual-level effects (days out of role per year) were associated with neurological disorders (17.4), bipolar disorder (17.3) and post-traumatic stress disorder (15.2). The strongest population-level effect was associated with pain conditions, which accounted for 21.5% of all days out of role (population attributable risk proportion). The 19 conditions accounted for 62.2% of all days out of role. Common health conditions, including mental disorders, make up a large proportion of the number of days out of role across a wide range of countries and should be addressed to substantially increase overall productivity.     

Prevalence, severity, and comorbidity of 12-month DSM-IV disorders in the National Comorbidity Survey Replication

BACKGROUND: Little is known about the general population prevalence or severity of DSM-IV mental disorders. OBJECTIVE: To estimate 12-month prevalence, severity, and comorbidity of DSM-IV anxiety, mood, impulse control, and substance disorders in the recently completed US National Comorbidity Survey Replication. DESIGN AND SETTING: Nationally representative face-to-face household survey conducted between February 2001 and April 2003 using a fully structured diagnostic interview, the World Health Organization World Mental Health Survey Initiative version of the Composite International Diagnostic Interview. PARTICIPANTS: Nine thousand two hundred eighty-two English-speaking respondents 18 years and older. MAIN OUTCOME MEASURES: Twelve-month DSM-IV disorders. RESULTS: Twelve-month prevalence estimates were anxiety, 18.1%; mood, 9.5%; impulse control, 8.9%; substance, 3.8%; and any disorder, 26.2%. Of 12-month cases, 22.3% were classified as serious; 37.3%, moderate; and 40.4%, mild. Fifty-five percent carried only a single diagnosis; 22%, 2 diagnoses; and 23%, 3 or more diagnoses. Latent class analysis detected 7 multivariate disorder classes, including 3 highly comorbid classes representing 7% of the population. CONCLUSION: Although mental disorders are widespread, serious cases are concentrated among a relatively small proportion of cases with high comorbidity.     

Chronic physical conditions and use of health services among persons with mental disorders: results from the Israel National Health Survey

OBJECTIVE: This study aimed to determine the association between common mental disorders and common chronic physical conditions and the contribution of mental disorders to the likelihood of being a higher user of health services. METHOD: A representative sample extracted from the National Population Register of noninstitutionalized residents of Israel aged 21 or older were interviewed at their homes between May 2003 and April 2004. Mental disorders were assessed using a revised version of the World Mental Health Composite International Diagnostic Interview. Chronic physical conditions were measured via a checklist of chronic physical disorders. RESULTS: Current mood or anxiety disorders were found to be associated with higher likelihood of chronic pain, cardiovascular conditions, diabetes and respiratory conditions beyond the sociodemographic characteristics and the risk factors (BMI or smoking). Current mood or anxiety disorders increased the likelihood of being a higher user of primary care beyond the effects of gender, population group, self-evaluation of general health, chronic pain or chronic conditions. CONCLUSION: The results regarding the prevalence of mental-physical comorbidity emphasize the need for integration in the physical and mental care of people with mental disorders.     

Age differences in the prevalence and co‐morbidity of DSM‐IV major depressive episodes: results from the WHO World Mental Health Survey Initiative

Background: Although depression appears to decrease in late life, this could be due to misattribution of depressive symptoms to physical disorders that increase in late life. Methods: We investigated this issue by studying age differences in co‐morbidity of DSM‐IV major depressive episodes (MDE) with chronic physical conditions in the WHO World Mental Health (WMH) surveys, a series of community epidemiological surveys of respondents in 10 developed countries (n=52,485) and 8 developing countries (n=37,265). MDE and other mental disorders were assessed with the Composite International Diagnostic Interview (CIDI). Organic exclusion rules were not used to avoid inappropriate exclusion of cases with physical co‐morbidity. Physical conditions were assessed with a standard chronic conditions checklist. Results: Twelve‐month DSM‐IV/CIDI MDE was significantly less prevalent among respondents ages 65+ than younger respondents in developed but not developing countries. Prevalence of co‐morbid mental disorders generally either decreased or remained stable with age, while co‐morbidity of MDE with mental disorders generally increased with age. Prevalence of physical conditions, in comparison, generally increased with age, while co‐morbidity of MDE with physical conditions generally decreased with age. Depression treatment was lowest among the elderly in developed and developing countries. Conclusions: The weakening associations between MDE and physical conditions with increasing age argue against the suggestion that the low estimated prevalence of MDE among the elderly is due to increased confounding with physical disorders. Future study is needed to investigate processes that might lead to a decreasing impact of physical illness on depression among the elderly. Depression and Anxiety, 2010. © 2009 Wiley‐Liss, Inc.     

Which mental disorders are associated with the greatest impairment in functioning?

Objective

The objective of this study is to estimate the comparative associations of mental disorders with three measures of functional impairment: the Global Assessment of Functioning (GAF); the number of days in the past 12 months of total inability to work or carry out normal activities because of emotions, nerves, or mental health (i.e., days out of role); and a modified version of the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0).

Methods

Secondary data analysis of the linked Mental Health Surveillance Study and the National Survey on Drug Use and Health (n?=?5653), nationally representative population surveys conducted in the United States. Generalized linear models assessed the independent effects of mental disorders on each measure of functional impairment, controlling for mental disorder comorbidity, physical health disorders, and sociodemographic factors.

Results

The results varied across measures of functional impairment. However, mood disorders generally tended to be associated with the greatest functional impairment, anxiety disorders with intermediate impairment, and substance use disorders with the least impairment. All 15 disorders were significantly associated with the GAF score in multiple regression models, eight disorders were significantly associated with the WHODAS score, and three disorders were significantly associated with days out of role.

Conclusions

Our results highlight the value of complementary measures of functional impairment.

     

Differential associations of Head and Body Symptoms with depression and physical comorbidity in patients with cognitive impairment

OBJECTIVE: To test the hypothesis that physical symptoms referred to the head might be specifically associated with depression in patients with cognitive impairment. METHODS: Subjects were taken from those enrolled in 'The Mild Project' a prospective study on the natural history of mild dementia (Mini Mental State Examination > or = 18) and with a diagnosis of Alzheimer's disease, vascular dementia, and mild cognitive impairment. A total of 129 subjects were included in the study. Physical symptoms were assessed with a checklist investigating nine different body organs or apparati. Physical symptoms were grouped into those referred to the head (Head Symptoms: ear and hearing; eyes and sight; and head and face) and all the others (Body Symptoms). Depressive symptoms were assessed with the Geriatric Depression Scale (GDS) and physical comorbidity with Greenfield's Index of Disease Severity (IDS). RESULTS: The number of patients reporting one or more Head Symptoms linearly increased with increasing depression severity (Mantel-Haenszel test = 6.497, df = 1, p = 0.011), while the number of patients reporting one or more Body Symptoms linearly increased with increasing physical comorbidity (Mantel-Haenszel test = 4.726, df = 1, p = 0.030). These associations were confirmed in multivariate logistic regression models with adjustment for potential confounders (age, gender, education, cognitive performance, daily function, and diagnosis). CONCLUSIONS: Head Symptoms are specifically associated with depression while Body Symptoms with physical comorbidity, in patients with cognitive impairment. Recognizing these associations in individual patients may help clinicians decide whether to initiate or continue antidepressant therapy or whether to carry out physical instrumental investigations.     

Comorbidity of physical and mental disorders and the effect on work-loss days

OBJECTIVE: To examine the association between physical and mental disorders and the separate and joint effect of physical and mental disorders on work-loss. METHOD: Data was derived from the Netherlands Mental Health Survey and Incidence Study. This was a general population study in which 7076 adults, aged between 18 and 64 years, were assessed using the Composite International Diagnostic Interview. Medically treated physical disorders and work-loss were assessed using self-reports. RESULTS: All physical disorders, except injury caused by accident, were significantly related to anxiety and mood disorders, but only weakly related to substance use disorders. Both physical and mental disorders were significantly related to work-loss; mental disorders more so than physical disorders. Physical-mental (PM) comorbidity leads to a mainly additive increase in work-loss. CONCLUSION: PM comorbidity is very common in the general population and leads to a greater absenteeism from work than pure disorders that also cause personal and social problems.     

Epidemiology of psychiatric and alcohol disorders in Ukraine

Background This study presents the lifetime, 12-month, and 1-month prevalence estimates of nine psychiatric and alcohol disorders in Ukraine assessed as part of the World Health Organization (WHO) World Mental Health (WMH) research program. The Ukraine WMH survey is the first psychiatric epidemiologic study in a former Soviet Union country to administer a structured psychiatric interview to a nationally representative sample. Method In 2002, a national probability sample of 4,725 respondents ages 18 and older were interviewed with the WMH version of the Composite International Diagnostic Interview (WMH-CIDI). Prevalence estimates, age-of-onset curves, comorbidity, demographic and geographic risk factors, and treatment seeking were examined. Results Close to one third of the population experienced at least one Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) disorder in their lifetime, 17.6% experienced an episode in the past year, and 10.6% had a current disorder. There was no gender difference in the overall prevalence rates. In men, the most common diagnoses were alcohol disorders (26.5% lifetime) and mood disorders (9.7% lifetime); in women, they were mood disorders (20.8% lifetime) and anxiety disorders (7.9% lifetime). The odds ratios for most pairs of disorders were highly significant. Age of onset was primarily in the teens and early 20s. Age, education, and living in the Eastern region of Ukraine were significant risk factors across disorders, with respondents older than 50 years having the highest prevalence of mood disorder and the lowest prevalence of alcoholism and intermittent explosive disorder. Only a minority of respondents talked to a professional about their symptoms. Conclusion Prevalence estimates of alcoholism among men and recent depression among women were higher in Ukraine than in comparable European surveys. The results argue for the need to develop and implement educational programs focused on the recognition and treatment of mental and alcohol disorders for the general population, psychiatrists, and general medical providers, who are the main source of mental health care.     

Prevalence of mental disorders among Māori in Te Rau Hinengaro: the New Zealand Mental Health Survey

OBJECTIVE: To describe the prevalence of mental disorders (period prevalence across aggregated disorders, 12 month and lifetime prevalence) among Māori in Te Rau Hinengaro: The New Zealand Mental Health Survey. METHOD: Te Rau Hinengaro: The New Zealand Mental Health Survey, undertaken between 2003 and 2004, was a nationally representative face-to-face household survey of 12,992 New Zealand adults aged 16 years and over, including 2,595 Māori. Ethnicity was measured using the 2001 New Zealand census ethnicity question. A fully structured diagnostic interview, the World Health Organization World Mental Health Survey Initiative version of the Composite International Diagnostic Interview (CIDI 3.0), was used to measure disorder. The overall response rate was 73.3%. This paper presents selected findings for the level and pattern of mental disorder prevalence among Māori. RESULTS: Māori lifetime prevalence of any disorder was 50.7%, 12 month prevalence 29.5% and 1 month prevalence 18.3%. The most common 12 month disorders were anxiety (19.4%), mood (11.4%) and substance (8.6%) disorders and the most common lifetime disorders were anxiety (31.3%), substance (26.5%) and mood (24.3%) disorders. Levels of lifetime comorbidity were high with 12 month prevalence showing 16.4% of Māori with one disorder, 7.6% with two disorders and 5.5% with three or more disorders. Twelve-month disorders were more common in Māori females than in males (33.6%vs 24.8%) and in younger age groups: 16-24 years, 33.2%; 25-44 years, 32.9%; 45-64 years, 23.7%; and 65 years and over, 7.9%. Disorder prevalence was greatest among Māori with the lowest equivalized household income and least education. However, differences by urbanicity and region were not significant. Of Māori with any 12 month disorder, 29.6% had serious, 42.6% had moderate and 27.8% had mild disorders. CONCLUSION: Mental disorders overall and specific disorder groups (anxiety, mood and substance) are common among Māori and measures of severity indicate that disorders have considerable health impact. Findings provide a platform for informing public health policy and health sector responses to meeting mental health needs of Māori.     

Co-occurrence of mental and physical illness in US Latinos

Background This study describes the prevalence of comorbid physical and mental health problems in a national sample of US Latinos. We examined the co-occurrence of anxiety and depression with prevalent physical chronic illnesses in a representative sample of Latinos with national origins from Mexico, Cuba, Puerto Rico, and other Latin American countries. Method We used data on 2,554 Latinos (75.5% response rate) ages 18 years and older from the National Latino and Asian American Study (NLAAS). The NLAAS was based on a stratified area probability sample design, and the sample came from the 50 states and Washington, DC. Survey questionnaires were delivered both in person and over the telephone in English and Spanish. Psychiatric disorders were assessed using the World Mental Health Survey Initiative version of the World Health Organization Composite International Diagnostic Interview (WMH-CIDI). Physical chronic illness was assessed by self-reported history. Results Puerto Ricans had the highest prevalence of meeting criteria for any comorbid psychiatric disorder (more than one disorder). Puerto Ricans had the highest prevalence (22%) of subject-reported asthma history, while Cubans had the highest prevalence (33%) of cardiovascular disease. After accounting for age, sex, household income, number of years in the US, immigrant status, and anxiety or depression, anxiety was associated with diabetes and cardiovascular disease, in the entire sample. Depression and co-occurring anxiety and depression were positively associated with having a history of asthma but not with other physical diseases, in the entire sample. Interestingly, Puerto Ricans with a depressive disorder had a lower odds of having a history of cardiovascular disease than Puerto Ricans without a depressive disorder. The relationship between chronic physical and mental illness was not confounded by immigration status or number of years in the US. Discussion Despite previous findings that link acculturation with both chronic physical and mental illness, this study does not find that number of years in the US nor nativity explain the prevalence of psychiatric-medical comorbidities. This study demonstrates the importance of considering psychiatric and medical comorbidity among specific ethnic groups, as different patterns emerge than when using aggregate ethnic measures. Research is needed on both the pathways and the mechanisms of comorbidity for the specific Latino groups.     

Comorbidity of the anxiety disorders in a community-based older population in The Netherlands

OBJECTIVE: The aim of the study was to investigate patterns of comorbidity among the anxiety disorders in a community-based older population, and the relationship of these disorders with major depression, use of alcohol and benzodiazepines, cognitive impairment and chronic somatic illnesses. METHOD: The data were derived from the Longitudinal Aging Study Amsterdam (LASA) study. A two-stage screening design was adopted to identify respondents with anxiety disorders. RESULTS: In total, 10% of the elderly with an anxiety diagnosis suffered from two or more anxiety disorders. Major depression (13% vs. 3%), benzodiazepine use (24% vs. 11%) and chronic somatic diseases (12% vs. 7%) were significantly more prevalent in respondents with an anxiety disorder than in respondents without anxiety disorders. Heavy or excessive alcohol intake (5% vs. 4%) and cognitive impairment (11% vs. 13%) were not significantly associated with any anxiety disorder. CONCLUSION: When anxiety disorders are diagnosed, in older people there is a relatively high probability of comorbid conditions being present.     

Prevalence, interference with life and severity of 12 month DSM-IV disorders in Te Rau Hinengaro: the New Zealand Mental Health Survey

OBJECTIVE: To estimate the 12 month prevalence of DSM-IV disorders in New Zealand, and associated interference with life and severity. METHOD: A nationally representative face-to-face household survey carried out in 2003-2004. A fully structured diagnostic interview, the World Health Organization World Mental Health Survey Initiative version of the Composite International Diagnostic Interview (CIDI 3.0) was used. There were 12,992 completed interviews from participants aged 16 years and over. The overall response rate was 73.3%. In this paper the outcomes reported are 12 month prevalence, interference with life and severity for individual disorders. RESULTS: The prevalence of any disorder in the past 12 months was 20.7%. The prevalences for disorder groups were: anxiety disorders 14.8%, mood disorders 7.9%, substance use disorders 3.5%, eating disorders 0.5%. The highest prevalences for individual disorders were for specific phobia (7.3%), major depressive disorder (5.7%) and social phobia (5.1%). Interference with life was higher for mood disorders than for anxiety disorders. Drug dependence, bipolar disorder and dysthymia had the highest proportion of severe cases (over 50%), when severity was assessed over the disorder itself and all comorbid disorders. Overall, only 31.7% of cases were classified as mild with 45.6% moderate and 22.7% serious. CONCLUSIONS: Compared with other World Mental Health survey sites New Zealand has relatively high prevalences, although almost always a little lower than for the US. For all disorders, except specific phobia, interference with life was reported to be moderate, on average, which has lead to less than a third of cases being classified as mild. Most people who have ever met full DSM-IV criteria, including the impairment criterion, and who experience symptoms or an episode in the past 12 months find that their disorders impact on their lives to a non-trivial extent.