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.

Global burden of depressive disorders in the year 2000.

BACKGROUND: The initial Global Burden of Disease study found that depression was the fourth leading cause of disease burden, accounting for 3.7% of total disability adjusted life years (DALYs) in the world in 1990. AIMS: To present the new estimates of depression burden for the year 2000. METHOD: DALYs for depressive disorders in each world region were calculated, based on new estimates of mortality, prevalence, incidence, average age at onset, duration and disability severity. RESULTS: Depression is the fourth leading cause of disease burden, accounting for 4.4% of total DALYs in the year 2000, and it causes the largest amount of non-fatal burden, accounting for almost 12% of all total years lived with disability worldwide. CONCLUSIONS: These data on the burden of depression worldwide represent a major public health problem that affects patients and society.

The International Classification of Functioning, Disability and Health: a new tool for understanding disability and health.

Reliable and timely information about the health of populations is part of the World Health Organization's mandate in the development of international public health policy. To capture data concerning functioning and disability, or non-fatal health outcomes, WHO has recently published the revised International Classification of Functioning, Disability and Health (ICF). In this article, the authors briefly outline the revision process and discuss the rationale for the ICF and the needs that it serves in rehabilitation. The ICF is shown to be an essential tool for identifying and measuring efficacy and effectiveness of rehabilitation services, both through functional profiling and intervention targeting. Existing applications of the ICF in rehabilitation are then surveyed. The ICF, in short, offers an international, scientific tool for understanding human functioning and disability for clinical, research, policy development and a range of other public health uses.

Understanding cross-national differences in depression prevalence.

UNLABELLED: BACKGROUND. Previous epidemiological studies indicate large cross-national differences in prevalence of depression. METHODS: At 15 centres in 14 countries. 25,916 primary care patients were screened for common mental disorders. A stratified random sample of 5,447 primary care patients completed a baseline diagnostic assessment and 3,197 completed a 12-month follow-up assessment. Psychiatric symptoms and diagnoses were assessed using the Composite International Diagnostic Interview (CIDI). Interviewer-rated disability was assessed using the Social Disability Schedule (SDS). RESULTS: Prevalence of current major depression varied 15-fold across centres. When centres were divided into three groups according to prevalence rates, the symptom pattern or latent structure of depressive illness was generally similar at low-, medium-, and high-prevalence centres. Depression was universally associated with disability, but this association varied significantly (t = 3.51, P = 0.0005) across centres. At higher-prevalence centres, depression was associated with lower levels of impairment. At 1 year follow-up, higher prevalence centres had both significantly higher rates of depression onset (t = 3.11, P = 0.002) and higher rates of persistence among those depressed at baseline (t = 2 49, P = 0.013). CONCLUSIONS: Large cross-national variations in depression prevalence cannot be attributed to 'category fallacy' (cross-national differences in the nature or validity of depressive disorder). Use of identical measures and diagnostic criteria may actually identify different levels of depression severity in different countries or cultures. Cross-national differences in the onset and outcome of depression may reflect either true prevalence differences or differences in diagnostic threshold.

Risk factors for new depressive episodes in primary health care: an international prospective 12-month follow-up study.

BACKGROUND: Studies that examined community samples have reported several risk factors for the development of depressive episodes. The few studies that have been performed on primary care samples were mostly cross-sectional. Most samples had originated from highly developed industrial countries. This is the first study that prospectively investigates the risk factors of depressive episodes in an international primary care sample. METHODS: A stratified primary care sample of initially non-depressed subjects (N = 2,445) from 15 centres from all over the world was examined for the presence or absence of a depressive episode (ICD-10) at the 12 month follow-up assessment. The initial measures addressed sociodemographic variables, psychological/psychiatric problems and social disability. Logistic regression analysis was carried out to determine their relationship with the development of new depressive episodes. RESULTS: At the 12-month follow-up, 44% of primary care patients met ICD-10 criteria for a depressive episode. Logistic regression analysis revealed that the recognition by the general practitioner as a psychiatric case, repeated suicidal thoughts, previous depressive episodes, the number of chronic organic diseases, poor general health, and a full or subthreshold ICD-10 disorder were related to the development of new depressive episodes. CONCLUSIONS: Psychological/psychiatric problems were found to play the most important role in the prediction of depressive episodes while sociodemographic variables were of lower importance. Differences compared with other studies might be due to our prospective design and possibly also to our culturally different sample. Applied stratification procedures, which resulted in a sample at high risk of developing depression, might be a limitation of our study.

Global "burden of disease"-study for psychiatric disorders.

The Global Burden of Disease (GBD) study was conducted to provide a set of summary health measures that would be comprehensive and make available information on disease and injury, including non-fatal health outcomes. The main objective of the GBD approach was to inform global priority setting for health research and to influence international health policy and planning. One of the summary measures used was the Disability Adjusted Life Year (DALY). DALYs are a common metric for fatal and non-fatal health outcomes and are based on years of life lost because of premature death (YLL) and years of life lived with disability (YLD). Thus DALYs = YLL + YLD or Burden = Mortality + Disability. Therefore, a DALY is one lost year of healthy life. The DALY methodology provides a way to link information on disease burden to cost-effectiveness analysis. This feature would assist comparative assessments. The WHO plans to refine this framework for assessing the outcomes of interventions and their related costs.

Stratum-specific likelihood ratios of two versions of the general health questionnaire.

BACKGROUND: In other branches of epidemiology, stratum specific likelihood ratios (SSLRs) have been found to be preferable to fixed best threshold approaches to screening instruments. This paper presents SSLRs of GHQ-12 and GHQ-28 and compares the SSLR method with the traditional optimal threshold approach. METHODS: Random effects meta-analysis and meta-regression were used to obtain pooled estimates of SSLRs of the two questionnaires for the 15 centres participating in the WHO study of Psychological Problems in General Health Care. We illustrated the use of SSLRs by applying them to random samples of patients from centres with different backgrounds. RESULTS: For developed and urban centres, the estimates of SSLRs were homogeneous for 10 out of 12 strata of the GHQ-12 and GHQ-28. For other centres, the overall results, which were heterogeneous for six out of 12 strata, were deemed the currently available best estimates. When we applied these results to centres with different prevalences of mental disorders and backgrounds, the estimates matched the actually observed closely. These examples showed how the SSLR approach is more informative than the traditional threshold approach. CONCLUSIONS: Those working in developed urban settings can use the corresponding SSLRs with reasonable confidence. Those working in non-urban or developing areas may wish to use the overall results, while acknowledging that they must remain less certain until further research can explicate heterogeneity. These SSLRs have been incorporated into nomograms and spreadsheet programmes so that future researchers can swiftly derive the post-test probability for a patient or a group of patients from a pre-test probability and GHQ score.

Consensus for the pharmacological management of insomnia in the new millennium.

Insomnia, a common symptom throughout the world, is characterised by difficulty initiating or maintaining sleep or non-restorative sleep and is associated with significant morbidity. A comprehensive medical and sleep history and physical examination are necessary before treating patients with insomnia; the presence of co-morbidities, including medical and psychiatric disorders, or the possible use of substances that may contribute to sleeplessness should be thoroughly investigated. Non-pharmacological approaches include correction of sleep hygiene as well as behavioural treatments. Pharmacotherapy includes benzodiazepine-receptor agonists, which are the drugs of choice for this disorder. They can be subdivided into classic benzodiazepines and non-benzodiazepines. Although many agents in these classes have been prescribed, potential shortcomings include residual sedation, rebound insomnia, and psychomotor and memory impairment. Novel pharmacological strategies that address limitations of the traditional treatment approach, combined with proven modes of behavioural therapy, offer the most successful results in the management of insomnia. These advances provide the opportunity to establish these current recommendations for the optimal management of insomnia. This report from the XXII Collegium Internationale Neuro-Psychopharmacologicum Consensus Workshop outlines recommendations to serve as the foundation for developing a therapeutic plan for each patient.

Identification of items which predict later development of depression in primary health care.

To improve recognition and treatment of depression in primary care it would be advantageous to have criteria for identification of later depression. Only a few studies were performed on primary care samples to examine risk factors for new depressive episodes. These were mostly cross-sectional and did not include psychiatric symptoms as possible predictors. This is the first one-year-follow-up study investigating prospectively psychiatric symptomatology as risk factors for depressive episodes in a primary care sample. An international primary care sample of initially non-depressed subjects (n = 2,445) was examined for the presence of depression (ICD-10) at follow-up. Initial measures addressed presence of psychiatric symptoms according to the CIDI-Primary Health Care Version and sociodemographic variables. Logistic regression analysis was carried out to determine the relationship with the development of new depressive episodes. After one year, 4.4% of primary care patients met ICD-10 criteria for a depressive episode. Logistic regression analysis revealed that symptoms of depression and physical, mainly pain-related symptoms were associated with depression at follow-up. General practitioners therefore should be careful in the consideration of depressive symptoms but also of somatic complaints which might precede depression or mask depressive symptomatology. The present results might be helpful for future development of prediction scales.

[Spanish version of the new World Health Organization Disability Assessment Schedule II (WHO-DAS-II): initial phase of development and pilot study. Cantabria disability work group]. / Versión en lengua española de un nuevo cuestionario de evaluación de discapacidades de la OMS (WHO-DAS-II): fase inicial de desarrollo y estudio piloto. Grupo Cantabria en Discapacidades.

The aim of the present paper is to present the initial phases of the development of the Spanish version of the "World Health Organization Disablement Assessment Schedule II" WHO-DAS-II and also to describe the quantitative and qualitative methodological strategies used in the elaboration process of an instrument: i) compatible with the new International Classification of Functioning and Disability -ICIDH-2- of the World Health Organisation; ii) with criteria of cross-cultural applicability and; iii) to allow us to assess the disability in all its dimensions.

Cross-national epidemiology of depression and gender.

Depressive disorders are 1.5 to 3 times more frequent in women than in men. This article reviews the evidence of gender differences in depression across countries in terms of definition, frequency, pattern, and burden. It attempts to confirm that these differences are real and not the result of any methodological bias; it examines what factors account for these differences; and it considers the implications of these differences for dealing with the increasing public health burden of this common mental disorder.

The global burden of mental disorders.

Recent data on the burden of mental disorders worldwide demonstrates a major public health problem that affects patients, society, and nations as a whole. Research must be done to find effective ways to deal with the increasing burden of mental disorders. Given the growing evidence that mental disorders are disorders of the brain and that they can be treated effectively with both psychosocial counseling and psychotropic medications, intervention packages could be developed to deal with the increasing burden. Such packages should be tested for real-world effectiveness and their cost-effectiveness should be demonstrated to guide policymakers to choose from among many other non-mental health interventions. The transportability and sustainability of intervention packages should be studied in public health research and a link between efficacy, effectiveness, cost-effectiveness, generalizability, and sustainability should be demonstrated. The World Health Organization's initiative on the World Mental Health 2000 Survey will provide the first basic epidemiologic data. Together with other data, the initiative will provide solid evidence for including mental disorders into essential treatment packages. In this way, parity can be achieved for mental disorders and mental health can be mainstreamed into health and public health practice.

Onset of disability in depressed and non-depressed primary care patients.

BACKGROUND: While cross-sectional and longitudinal studies have consistently found depressive illness and disability to be related, understanding whether depression leads to subsequent onset of disability is limited. METHODS: In the context of the multi-centre international WHO Collaborative Study on Psychological Problems in General Health Care, we followed prospectively consulting non-elderly primary care patients who were essentially disability free at baseline but who differed in baseline depression status, comprising 1051 patients free of physical disability at baseline including 14% depression; 914 free of social disability including 9% depression. Depression status was assessed with the CIDI; patient-reported physical disability with the MOS physical functioning scale and social disability with the BDQ role functioning and number of disability days measures; investigator-rated social disability with the Occupational section of Groningen Social Disability schedule; and the treating physicians rated the severity of physical illness. RESULTS: In patients essentially disability free at baseline, depressive illness resulted in a 1.5-fold (at 3 months) and a 1.8-fold (at 12 months) increase in risk of onset of physical disability, after controlling for physical disease severity. Depressive illness also resulted in a 2.2-fold (at 3 months) and a 23-fold (at 12 months) increase in risk of onset of social disability, after controlling for physical disease severity, physical disability and onset of physical disability. CONCLUSIONS: Among non-elderly primary care patients, depressive illness is associated with onset of physical disability and shows an even stronger association with onset of social disability.

Multiple-informant ranking of the disabling effects of different health conditions in 14 countries. WHO/NIH Joint Project CAR Study Group.

BACKGROUND: The Global Burden of Disease study provided international statistics on the burden of diseases, combining mortality and disability, that can be used for priority setting and policy making. However, there are concerns about the universality of the disability weights used. We undertook a study to investigate the stability of such weighting in different countries and informant groups. METHODS: 241 key informants (health professionals, policy makers, people with disabilities, and their carers) from 14 countries were asked to rank 17 health conditions from most disabling to least disabling. Kruskal-Wallis ANOVA was used to test for differences in ranking between countries or informant groups and Kendall tau-B correlations to measure association between different rank orders. FINDINGS: For 13 of 17 health conditions, there were significant (p<0.05) differences in ranking between countries; in the comparison of informant groups, there were significant differences for five of the 17 health conditions. The overall rank order in the present study was, however, almost identical to the ranking of the Global Burden of Disease study, which used a different method. Most of the rank correlations between countries were between 0.50 and 0.70 (average 0.61 [95% CI 0.59-0.64]). The average correlation of rank orders between different informant groups was 0.76. INTERPRETATION: Rank order of disabling effects of health conditions is relatively stable across countries, informant groups, and methods. However, the differences are large enough to cast doubt on the assumption of universality of experts' judgments about disability weights. Further studies are needed because disability weights are central to the calculation of disability-adjusted life years.

Outcomes of recognized and unrecognized depression in an international primary care study.

Longitudinal data from the World Health Organization Psychological Problems in General Health Care study were used to examine the relationship between recognition and outcomes among depressed primary care patients. A representative sample of primary care patients at 15 sites completed a baseline assessment including the Composite International Diagnostic Interview (CIDI), the 28-item General Health Questionnaire (GHQ), and the Brief Disability Questionnaire (BDQ). The GHQ and BDQ were readministered after 3 months, and the GHQ, BDQ, and CIDI were readministered after 12 months. Of 948 patients with major depression at the baseline assessment, 42% were recognized by the primary care physician and given an appropriate diagnosis. Recognized patients were more severely ill (mean GHQ score 16.2 vs. 12.9, t = 5.44, p < 0.001) and more disabled (mean BDQ score 9.8 vs 8.2, t = 3.22, p < 0.001) at baseline. Recognized patients showed a significantly greater decrease in GHQ score at the 3-month assessment (6.1 vs 4.1, F = 5.33, df = 1, p = 0.02). At 12 months, recognized and unrecognized groups did not differ in either change in GHQ score or change in diagnostic status from baseline. Results were consistent across study sites. Our data suggest that recognition and appropriate diagnosis of depression in primary care is associated with significantly greater short-term improvement. The absence of a relationship between recognition and long-term outcomes may reflect limitations of this observational study. When considered along with other recent studies, these findings suggest that increasing recognition of depression in primary care is only a first step toward more appropriate treatment.

Models of disablement, universalism and the international classification of impairments, disabilities and handicaps.

A review and critique of models of disability is presented, tracing the development of frameworks and classificatory instruments (International Classification of Impairments, Disabilities and Handicaps) over the past 20 years. While the 'social' model is now universally accepted, it is argued that universalism as a model for theory development, research and advocacy serves disabled persons more effectively than a civil rights or 'minority group' approach. The development of the revised International Classification (ICIDH-2) is discussed in this light.

Factor structures for DSM-IV substance disorder criteria endorsed by alcohol, cannabis, cocaine and opiate users: results from the WHO reliability and validity study.

AIMS: The factor structure of DSM-IV substance disorder criteria is examined among alcohol, cannabis, cocaine and opiate users to determine the dimensionality of abuse and dependence criteria within each of these drug classes and whether a common construct can be generalized across drug classes. DESIGN: 12-month criterion prevalence was assessed as part of the World Health Organization's Study on the Reliability and Validity of the Alcohol and Drug Use Disorder Instruments in various settings at eight sites around the world using the Schedules for Clinical Assessment in Neuropsychiatry (SCAN). A majority of respondents were recruited from non-treatment settings. In addition to exploratory factor analysis, confirmatory factor analysis was used to analyse factor structures using weighted least square methods and tetrachoric correlation matrices. Multi-sample analysis techniques were used to model differences between drug-classes. FINDINGS: In the full data analyses identified a single factor solution for each user population and across user populations. However, analyses of data from users reporting low to moderate symptomatology identified a two-dimensional construct among alcohol, cannabis and opiate users consisting of a major "dependence" factor and a lesser "abuse" factor. In addition, results showed that neither the abuse criterion "(A2) use in physical hazardous situations" or the dependence criterion "(D7) use despite knowledge of psychological/physical problems" were central to the latent construct in any of the user populations, except for D7 among alcohol users. CONCLUSIONS: The multi-dimensional results found among users with low to moderate symptomatology indicate that: (1) previous results from relatively homogeneous populations may have been biased towards lesser order solutions, and that (2) the DSM-IV substance disorder criteria describe at least two distinct phenomena, supporting the current DSM-IV organization of substance disorder criteria. Further work needs to evaluate whether prevalent symptoms are present in random or predictable combinations, whether combinations reflecting a specific hierarchy of severity can be identified, and whether incident symptoms are accumulated in a predictable pattern, within specific user populations and across user populations.