Estimating the true global burden of mental illness

Challenges to estimating the true global burden of mental disorders – Authors' reply

SummaryBackgroundEpidemiological and economic estimates suggest that the global burden of mental disorders is considerable, both in its impacts on human health and losses to societal welfare. The availability of additional data and the emergence of new approaches present an opportunity to examine these estimates, which form a critical part in making the investment case for global mental health.MethodsThis study reviews, develops, and incorporates new estimates and methods in quantifying the global burden of mental illness. Using a composite estimation approach that accounts for premature mortality due to mental disorders and additional sources of morbidity and applying a value of a statistical life approach to economic valuation, we determine global and regional estimates of the economic cost that can be associated with mental disorders, building on data from the 2019 Global Burden of Disease study.FindingsWe estimate that 418 million disability-adjusted life years (DALYs) could be attributable to mental disorders in 2019 (16% of global DALYs)—a more than three-fold increase compared to conventional estimates. The economic value associated with this burden is estimated at about USD 5 trillion. At a regional level, the losses could account for between 4% of gross domestic product in Eastern sub-Saharan Africa and 8% in High-income North America.InterpretationThe burden of mental illness in terms of both health and economic losses may be much higher than previously assessed.FundingNone.

Few areas of medicine have posed a greater challenge to the adoption of a population-level or epidemiologic approach than psychiatry. From the privacy required for many therapeutic methods to the complexity and seeming individuality of each patient, the history and nature of mental illness has often appeared antithetical to the epidemiologic method. At the same time, the prevalence, severity, and overall burden of morbidity and mortality represented by mental disorders reflects an urgent global public health concern ripe for the application of epidemiology. The gains realized through advances in psychiatric epidemiology over the past decade, the resulting potential of an empirically informed, population-oriented approach to reducing the global burden of mental illness, and major methodological challenges for the field are highlighted in the current issue of Epidemiologic Reviews, which accompanies this issue of the Journal. It has been over a decade since the last issue of Epidemiologic Reviews dedicated to psychiatric epidemiology appeared in 1995. Despite impressive advances in genetics, neuroscience, brain imaging, and other technologies during these past 13 years, the scope and magnitude of the problem are no less demanding. High-quality epidemiologic investigations in the United States and worldwide have yielded quite consistent estimates of the prevalence of major mental disorders. Data from the recent replication of the National Comorbidity Survey, a representative sample of US adults, suggest that an estimated 13 million American adults (approximately 1 in 17) have a seriously debilitating mental illness (1, 2). The strikingly prominent place of mental disorders in the total pattern of morbidity and mortality worldwide was highlighted in the World Health Organization's initial Global Burden of Disease (3) report, a finding that has been sustained in recent updates (4). According to World Health Organization estimates for 2002, mental health disorders are the leading cause of disability in the United States and Canada, accounting for 25% of all years of life lost to disability and premature mortality (4). Worldwide, it is estimated that mental disorders account for 12% of disability-adjusted life years. In terms of mortality, suicide alone is the 11th leading cause of death in the United States, with approximately 30,000 deaths per year (5), and this is an issue of concern worldwide as well. Estimating the costs associated with mental illness is challenging, but estimates suggest annual treatment costs in the United States of $100 billion, with significantly more for indirect costs; $193 billion per year is estimated for lost earnings alone (2). While these findings reveal concrete developments in the foundations of psychiatric epidemiology (standardized and replicated nosology; high-quality prevalence estimates), advances in the identification of risk factors, etiologic mechanisms, and preventive interventions have been more modest. For instance, a 2004 literature review commissioned by the National Institute of Mental Health revealed that while there has been considerable growth in the number of high-quality longitudinal studies with well-characterized psychiatric outcomes, there is strikingly little consistency in the coverage, measurement, and (therefore) replication of potential risk factors across investigations (6). Clearly, considerable ground remains to be covered in psychiatric epidemiology to move from statements of prevalence to insights regarding disease etiology and prevention. The forthcoming issue of Epidemiologic Reviews provides an informative summary of many of these strengths and challenges in psychiatric epidemiology. The 10 articles in the issue provide a succinct presentation of the many contributions the field brings to broadening the knowledge base and investigating strategies for disease prevention in the realm of mental illness. These include: 1) detailed narrative reviews of the epidemiology of individual disorders (schizophrenia (7), suicide (8), and Alzheimer's disease (9)); 2) systematic reviews and meta-analyses of exposure-disease associations of long-standing interest (place of residence/neighborhood attributes and risks of both depression (10) and psychosis (11), working conditions and depression (12), premorbid intelligence quotient and psychosis (13)); 3) major findings and methodological advances regarding the analysis of co-occurring or “comorbid” forms of psychopathology (14); 4) challenges and opportunities in moving from observational studies to preventive clinical trials (15); and 5) an overarching summary of the prevalence, impairment, and cost associated with 11 major mental disorders of adults (16). One clear sign of encouragement from this body of work is that the number of well-conducted prospective and cross-sectional population-based studies is considerable and growing. On the basis of these studies, the authors in this special issue have been able to not only summarize more accurately the prevalence and incidence of major adult disorders but, more interestingly, also discern meaningful variation in disease distributions that set the stage for new etiologic investigations. For example, Nock et al.'s review of global suicide and suicidal behavior (8) concludes that “the significant cross-national variability… appears to reflect the true nature of this behavior and is not due to variation in research methods” and proceeds to elaborate new methodological and theoretical advances that are likely to yield new insight into the origins of these behaviors. Similarly, McGrath et al. (7) challenge the common perception that the incidence and prevalence of schizophrenia are relatively even across regions, and they highlight a number of potential risk factors related to urbanicity, economic status, migrant status, and latitude that might play an etiologic role and account for this variation. Despite these positive advances, Eaton et al.'s summary of the “global burden” associated with adult mental disorders (16) provides succinct guidance by highlighting a number of disorders for which basic incidence and prevalence data are sparse and how extremely limited are even the most rudimentary data on disability, mortality, and costs. With a focus on a range of potential etiologic factors ranging from social conditions to specific polymorphisms, psychiatric epidemiology has been and should continue to be recognized as related to but distinct from other branches of our discipline, most notably social epidemiology (17). At the same time, the methodological and conceptual advancements of social epidemiology have enhanced a long-standing tradition of inquiry into the impact of the broader social environment on the genesis of mental illness. These cross-fertilizations are elegantly displayed with the work of March et al. (11) and Kim (12). Kim's systematic review of 28 studies (12) supports a positive association between neighborhood social disorder and depression and to a lesser extent suggests protective effects for neighborhood socioeconomic status. March et al. (11) observe positive associations between urbanicity, ethnic density, social isolation, and nonaffective (but not affective) psychoses. Both papers provide a compelling impetus for new lines of inquiry and the possibility of community-level (rather than more traditional individual-level) interventions for the prevention or minimization of these high-burden disorders. Finally, the contribution by Cerda et al. (14) reminds us that while most investigators consider single disease endpoints, co-occurrence or comorbidity both is common and greatly increases the burden on patient and society. Their careful summary of findings from 58 articles documents the extent of comorbidity, summarizes conceptual approaches that will be needed to account for it, and makes valuable recommendations for the future research that will be required to obtain new insight into the pathways leading to such co-occurrence. This special issue of Epidemiologic Reviews provides an excellent summary of the ground covered and the road ahead regarding the epidemiologic investigation and public health strategies needed to reduce the prevalence, severity, and impairment resulting from mental illness. It provides high-quality, well-written summaries of large bodies of literature and sheds new light on both the limitations of standard epidemiologic approaches in this arena and valuable future directions for the field. Old-timers in the field will read it with a sense of appreciation for the advances we have made, while newcomers will be energized and stimulated by an awareness of the immediacy of the problem and the clear avenues available for meaningful new discovery.

BackgroundThe global burden of mental illness is high and opportunities for promoting mental health are neglected in most parts of the world. Many people affected by mental illness live in developing countries, where treatment and care options are limited. In this context, primary health care (PHC) programs can indirectly promote mental health by addressing its determinants i.e. by enhancing social unity, minimising discrimination and generating income opportunities. The objectives of this study were to: 1. Describe concepts of mental health and beliefs about determinants of mental health and illness among women involved with a PHC project in rural Maharashtra, India; 2. Identify perceived mental health problems in this community, specifically depression, suicide and violence, their perceived causes, and existing and potential community strategies to respond to them and; 3. Investigate the impact of the PHC program on individual and community factors associated with mental healthMethodWe undertook qualitative in-depth interviews with 32 women associated with the PHC project regarding: their concepts of mental health and its determinants; suicide, depression and violence; and the perceived impact of the PHC project on the determinants of mental health. The interviews were taped, transcribed, translated and thematically analysed.ResultsMental health and illness were understood by these women to be the product of cultural and socio-economic factors. Mental health was commonly conceptualised as an absence of stress and the commonest stressors were conflict with husbands and mother-in-laws, domestic violence and poverty. Links between empowerment of women through income generation and education, reduction of discrimination based on caste and sex, and promotion of individual and community mental health were recognised. However, mental health problems such as suicide and violence were well-described by participants.ConclusionWhile it is essential that affordable, accessible, appropriate treatments and systems of referral and care are available for people with mental illness in developing country settings, the promotion of mental health by addressing its determinants is another potential strategy for reducing the burden of mental illness for individuals and communities in these settings.

Ensuring care for people with depression

Mental disorders are the main cause of the young and economically active population worldwide and in Brazil to live with disabilities, being an important public health problem nowadays. The objective was to estimate the burden of mental disorders among professionals working to combat endemic diseases in a state in northeastern Brazil. Medical records of workers linked to the Brazilian Ministry of Health in Ceará State and fighting endemic diseases were surveyed and, from this, a historical cohort was made. The individual quantification of absenteeism by mental disorders (ICD F-chapter referring to mental disorders) was conducted considering a period of about 35 years, from admission (the 1980s) to December 2017. The global burden of disease was measured by the YLD indicator (years lost to disability). Considering that no deaths due to mental disorders were observed, the YLL indicator (years of life lost) was composed. The high mental disorders burden in this group of workers stands out, whose mood disorders, including depression, conferred a YLD equal to 18.6. This represents just over 18 years of work lived with a disability. Our findings reinforce the need to implement surveillance and health promotion actions in workers to promote effective interventions capable of contributing to the reduction of morbidity in workers and economically active people.

ObjectivesWe aimed to assess the burden of disease (BOD) of the residents living in contaminated coastal area with oil spill and also analysed the BOD attributable to the oil spill...

Global, regional, and national disability-adjusted life years (DALYs) for 306 diseases and injuries and healthy life expectancy (HALE) for 188 countries, 1990–2013: quantifying the epidemiological transition

The Global Burden of Disease Study 2010 (GBD 2010) was launched in December 2012 and a special issue of The Lancet was published, dedicated to reporting the results [1]. GBD 2010 is a systematic and comprehensive assessment of data on 291 diseases and injuries and 235 causes of death for 20 age groups, both sexes, and for 187 countries, producing estimates of mortality and of non-fatal health outcomes [1]. GBD 2010 assessed significantly more health conditions than the previous version of the study and for the first time included attention-deficit/hyperactivity disorder, conduct disorder, and autism. This is an important advance to our field because the objective estimates of the burden of childhood mental disorders contextualize these conditions among all other medical conditions and support governmental and societal actions. Results show that there is an increasing burden of non-communicable diseases and mental illnesses and substance use disorders are among the main causes of disability [1]. Mental and behavioral disorders caused approximately 185 million disability-adjusted life years (DALYs) accounting for 7.4 % of DALYs globally [2]. Pervasive development disorders caused approximately 7.5 million, conduct disorder caused approximately 6 million and ADHD caused approximately half a million DALYs [2]. Mental and behavioral disorders caused approximately 177 million years lived with disability (YLDs) accounting for 22.7 % of YLDs globally [3]. Pervasive development disorders caused approximately 7.6 million, conduct disorder caused approximately 5.7 million and ADHD caused approximately 400,000 YLDs [3]. The process of estimating DALYs and YLDs is complex and depends on the available literature, which imposed limitations in the process possible resulting in underestimates of the burden of childhood mental disorders. Due to the limitations imposed by the literature, mortality was not calculated for childhood mental disorders [4]. There is no doubt that mental disorders in childhood are associated with premature death, as Halfon’s et al. [5] study demonstrated by examining studies on suicidality in youth bipolar disorder and summarizing the risk and protective factors detected by individual studies. Youth bipolar disorder is strongly associated with suicidal behavior, as indicated by several studies and more recently by the National Comorbidity Survey Replication Adolescent Supplement in the general population of the US [6]. A number of clinical characteristics that further increase the risk for suicidal behavior were identified, such as an acute episode, psychotic symptoms, and comorbid conditions, in conjunction with psychological characteristics, family and social factors. Of note, dialectical behavior therapy was found to protect against suicidality by improving emotional regulation and depressive symptoms. Additionally, authors were not able to find studies assessing the effect of lithium on suicidal risk. As this medication was found to decrease the risk of suicide in adults with bipolar disorder, it would be highly relevant to test if this effect also applies to youths. Another limitation imposed to the GBD 2010 study is the fact that childhood disorders are associated to complex chains of risk factors as causes and consequences, G. V. Polanczyk (&) Department of Psychiatry, Medical School and Research Support Center on Neurodevelopment and Mental Health, University of Sao Paulo, Rua Dr. Ovidio Pires de Campos 785, Sao Paulo, SP 05403-010, Brazil e-mail: gvp@usp.br

BackgroundThe Global Burden of Disease Study 2010 (GBD 2010), estimated that a substantial proportion of the world’s disease burden came from mental, neurological and substance use disorders. In this paper, we used GBD 2010 data to investigate time, year, region and age specific trends in burden due to mental, neurological and substance use disorders.MethodFor each disorder, prevalence data were assembled from systematic literature reviews. DisMod-MR, a Bayesian meta-regression tool, was used to model prevalence by country, region, age, sex and year. Prevalence data were combined with disability weights derived from survey data to estimate years lived with disability (YLDs). Years lost to premature mortality (YLLs) were estimated by multiplying deaths occurring as a result of a given disorder by the reference standard life expectancy at the age death occurred. Disability-adjusted life years (DALYs) were computed as the sum of YLDs and YLLs.ResultsIn 2010, mental, neurological and substance use disorders accounted for 10.4% of global DALYs, 2.3% of global YLLs and, 28.5% of global YLDs, making them the leading cause of YLDs. Mental disorders accounted for the largest proportion of DALYs (56.7%), followed by neurological disorders (28.6%) and substance use disorders (14.7%). DALYs peaked in early adulthood for mental and substance use disorders but were more consistent across age for neurological disorders. Females accounted for more DALYs in all mental and neurological disorders, except for mental disorders occurring in childhood, schizophrenia, substance use disorders, Parkinson’s disease and epilepsy where males accounted for more DALYs. Overall DALYs were highest in Eastern Europe/Central Asia and lowest in East Asia/the Pacific.ConclusionMental, neurological and substance use disorders contribute to a significant proportion of disease burden. Health systems can respond by implementing established, cost effective interventions, or by supporting the research necessary to develop better prevention and treatment options.

Strengthening Mental Health in UN’s Sustainable Development Goals

Objective: Research on Mental Health Literacy (MHL) has not been gained ample focus from policymakers and researchers particularly in developing countries. SDG 3.4 by 2030,associated with lowering the prevalence of non-communicable diseases including mental health problems through effective interventions. This study aims to initiate an insight into the role of MHL research among youth, against the increasing burden of mental illness, through a bibliometric review. Methods: Scopus database was used to excerpt pertinent MHL research among youth published from 1977 to 2020 across the globe. This review identified the major components which can be listed under the following themes that include the trend of research work, the top most countries, authors, and institutions.Results: The Scopus database was used to extract 225 research articles. The gradual escalation in the number of publications on MHL was noticed. The trend of citations showed declination.Developed countries have more focused on mental health literacy research among youth than in developing countries.Conclusion: Considering the global burden of mental illness among the youth, the quantity and quality of MHL research steered among youth across the globe is discontented. Greater attention from policymakers and researchers is required to address the prevalence of mental illness, by offering adequate MHL to the youth

Addressing the Global Burden of Mental Illness: Why Transdiagnostic and Common Elements Approaches to Evidence-Based Practice Might Be Our Best Bet

Although efficacious psychotherapies exist, a limited number of mental health care providers and significant demand make their accessibility a fundamental problem. Clinical researchers, funders, and investors alike have converged on self-help digital mental health interventions (self-help DMHIs) as a low-cost, low-burden, and broadly scalable solution to the global mental health burden. Consequently, exorbitant financial and time-based resources have been invested in developing, testing, and disseminating these interventions. However, the public's assumed desirability for self-help DMHIs by experts has largely proceeded without question. This commentary critically evaluates whether self-help DMHIs can, and will, reach their purported potential as a solution to the public burden of mental illness, with an emphasis on evaluating their real-world desirability. Our review finds that self-help DMHIs are often perceived as less desirable and credible than in-person treatments, with lower usage rates and, perhaps accordingly, clinical trials testing self-help DMHIs suffering from widespread recruitment challenges. We highlight two fundamental challenges that may be interfering with the desirability of, and engagement in, self-help DMHIs: (1) difficulty competing with technology companies that have advantages in resources, marketing, and user experience design (but may not be delivering evidence-based interventions) and (2) difficulty retaining (vs initially attracting) users. We discuss a range of potential solutions, including highlighting self-help DMHIs in public mental health awareness campaigns; public education about evidence-based interventions that can guide consumers to appropriate self-help DMHI selection; increased financial and expert support to clinical researchers for marketing, design, and user experience in self-help DMHI development; increased involvement of stakeholders in the design of self-help DMHIs; and investing in more research on ways to improve retention (versus initial engagement). We suggest that, through these efforts, self-help DMHIs may fully realize their promise for reducing the global burden of mental illness.

Mental illness is a significant factor in disease related disability throughout the world. About 16% of the global burden of disease not attributable to communicable disease has been attributed to mental disorders (Prince et al 2007) with substance abuse disorders contributing to a further 4% of this burden (ibid). In Australia, “Mental Disorders” were considered to be the third major cause of health loss (behind cancer and cardiovascular disease) in 2003 but were estimated to increase at a significant rate to move ahead of cancer and become the second major cause of “health loss” by 2013 (Begg et al 2008). This burden of mental illness is particularly pronounced in the youth of Australia with disabilityadjusted life years (DALY’s) for mental illness calculated to be above 90,000 (compared to the next highest of 48,000 DALY’s due to injury) for the 15 to 24 year old age group in 2003 (Eckersley 2011). Along with the current burden of disease attributed to mental illness, there is a number of challenges facing societies in the developed and developing world that are likely to lead to an increase in mental illness. Sartorius (pers comm) has recently outlined some of these challenges. They include: weakening of community resilience mechanisms, increasing awareness of gaps and unreachable opportunities, migration of people, talents and capital with the subsequent loss of social capital in some societies, the challenges of increased urbanisation on community supports and family structures, the changing nature of privileged families in developed society with less children, longer life spans and more fragile family structures, the decrease of middle class “norms” in developed countries and the additional increase of the middle class in developing countries with potential economic and social alienation from less privileged groups, the changing role of women and the implications that this has for child care and care of the elderly and the changing paradigms of medicine itself with increasing use of technology in addition to evolving ethical issues such as euthanasia. The severity of personal disability from mental illness is pervasive. The poetry of Anne Sexton in the poem “Sickness unto Death” (1977) helps describe some of this inner experience for severe mood disorder: