The World Health Organization recently reported that mental health disorders account for a significant proportion of disability adjusted life years (DALYs), responsible for 37% of the healthy years of life lost due to chronic non-communicable diseases, with depression alone accounting for one third. WHO called for action.
Three objectives were pursued: First, identify prevalence of mental health disorders and its related costs; second and third, identify WHO recommendations and identify efficient interventions for mental disease prevention and mental health promotion.
A non-exhaustive non-systematic review of the literature via two data-basis (Medline, and Scholar Google) and several keywords (mental health, prevalence, burden of disease, health costs, prevention, health promotion, health policy recommendations) was undertaken.
Mental health disorders constitute 13% of the global burden of disease. Unipolar depressive disorders are the leading course of disability adjusted life years as well in high-income countries as in low and middle-income countries. Over 80% of people with severe mental disorders receive no treatment in low-income countries; 35 to 50% in high-income countries. By 2030 the costs of mental health disorders will exceed 6 trillion US $, doubling from current costs. Research shows that effective and efficient mental disease prevention and mental health promotion interventions exist and should get more attention from the health authorities. Given the gravity of the situation the 66th World Health Assembly adopted the 2013-2020 Action Plan for Mental Health setting four broad objectives, which are in line with the proposal of an international consortium of researchers.
Given the public health importance of mental health problems and their economic impact, given also the awareness of health authorities the importance that mental health issues should be addressed, one should remember that many effective and efficient health promoting interventions regarding mental health exist.
The World Health Organization (WHO) has defined mental health as “a state of well-being in which every individual realizes his or her own potential, can cope with the normal stresses of life, can work productively and fruitfully, and is able to make a contribution to her or his community” . Mental health promotion therefore aims “at enhancing individual’s ability to achieve psychosocial well-being and at coping with adversity” . As for the definition of mental disorders, WHO states that it “comprises a broad range of problems, with different symptoms, which are generally characterized by some combination of abnormal thoughts, emotions, behavior and relationships with others (e.g. schizophrenia, depression, intellectual disabilities and disorders due to drug abuse”. Mental disorder prevention thus “focuses on the causes of risk factors to avoid illness“. WHO in its World Health Report 2001 Mental Health: New Understanding, New Hope states that “mental health – neglected for far too long – is crucial to the overall well-being of individuals, societies and countries and must be universally regarded in a new light” . In our review we pursued 3 objectives in order to better understand the importance of mental health disorders in a public health perspective: First, identify the prevalence of mental health disorders and its related costs; second identify WHO recommendations for action and third identify efficient interventions for mental disorders prevention and mental health promotion.
A non-exhaustive non-systematic review of the literature via two databases (Medline, and Scholar Google) and several keywords (mental health, prevalence, burden of disease, health costs, prevention, health promotion, health policy recommendations) was undertaken. We essentially focused on WHO reports, meta-analysis of systematic reviews and reviews of original studies.
The public health importance of mental health disorders: In the 1990s, worldwide studies estimating the Global Burden of Disease and the years of disability have highlighted the importance of mental health disorders , considering that they will account for 15% of the total of the burden of disease by 2020 . It has been reported that mental health disorders account for a significant proportion of disability adjusted life years (DALYs), accounting for 37% of the healthy years of life lost due to chronic noncommunicable diseases  , with depression alone accounting for one third .
A review of the situation in 28 countries in the different WHOregions found that anxiety disorders were the most frequent of all mental health disorders in the population (lifetime prevalence of 16% and annual prevalence of 11 %), followed by mood disorders (lifetime prevalence 12% and annual 6%) . According to WHO estimates in 2004, depression accounts for 8.3% of all years lived with disabilities (YLD) in men and 13.4% in women [8,10]. Worldwide unipolar depressive disorders account for 65.5 million DALYs (10 in high-income countries and 55.5 in low- and middle-income countries) .
Estimates from high-income countries (in this case it is Europe) indicate that 38.2% of the population suffer from at least one mental health problem every year, or 164.8 million people. “The most common disorders are anxiety states, insomnia, major depression, somatogenic disorders, alcohol dependence and other drugs, hyperactivity with attention disorder in children, and dementia . With the exception of substance abuse and mental retardation, there are no significant differences between countries or cultures “. In terms of disability, brain and mental health disorders account for 26.6% of the total burden of disease, with depression, dementia, alcohol abuse and stroke being the most frequent pathologies  . In low- and middle-income countries mental disorders account for 11.1% of the global burden of disease, unipolar depressive disorders being the leading cause with 3.1% . Furthermore, in low- and middle-income countries the burden attribuable to mental disorders in young adults is even higher, unipolar depressive disorders representing 8.6%, alcohol use disorders 3.0%, schizophrenia 2.6% and bipolar affective disorders 2.5% of the global burden of disease in this age-group (15-44 years). Seventy-five percents of the 800’000 suicides occur in low- and middle-income countries , while the estimates of median prevalence rates of common mental disorders, i.e depressive and anxiety disorders (based on 11 studies from African, Asian and South American countries) varies between 20% and 30% .
In low- and middle-income countries about 80% of people with severe mental disorders receive no treatment. For high-income countries, this proportion varies between 35% and 50% . Access to medication and care are especially weak in low-income countries: e.g. “in 83% of low-income countries there are no anti-Parkinson treatments in primary-care” , e.g. there are 200 times more psychiatrists in European countries than in Africa .
The Economic Costs of Mental Health Disorders: A recent document from the World Economic Forum  describes 3 different approaches for estimating the economic burden of mental disorders: First, the human capital costs, i.e. direct and indirect costs , associated with mental health disorder totaled US $ 2.5 trillion (0.8 trillion direct costs, 1.7 trillion indirect costs) in 2010. By 2030, these costs are expected to exceed US $ 6.0 trillion , 2/3 of which occur in high-income countries. Second, the lost economic growth, i.e. depletion of capital and depletion of labor , between 2011 and 2030 will be as high as US $ 16.3 trillion according to these estimates . Third, thevalue of statistical life , i.e. the quantification of the risk of death or disability associated with mental disorders, was estimated at US $ 8.5 trillion in 2010 and it will double by 2030 . Indeed, overall economic costs of mental disorders are very important, exceeding even the overall costs of somatic diseases such as diabetes or cancer . Overall, mental health spending represents US $ 2 per person per year, and “67% of these resources go to psychiatric hospitals despite poor health outcomes and human rights violations” (within these structures) .
Concerning the situation in Europe, Gustavsson and colleagues  reported specific disease-related economical data. They estimated costs of mental health disorders as follows: Mood disorders (depression): € 113 billion; Dementia: €105 billion; Anxiety disorders: € 66illion; Addictions: €66 billion; Psychoses: €29 billion with a significant increase in the future. Furthermore, the cost projections by Knapp et al. established for England for the years 2007 to 2026 the following evolution: Dementia: £ 14.9 / £ 34.8 billion; Anxiety disorders: £ 8.9 / £ 14.2 billion; Personality disorders: £ 7.9 / £ 12.3 billion; Depression: 7.5 /12.2 billion; Bipolar disorders: 5.2 /8.2 billion; Schizophrenia: 4.0 / 6.5 billion £ .
Mental Health, a call for action: In 2013, the 66th WHO World Health Assembly adopted the 2013-2020 Mental Health Action Plan , following the recommendations of the 65th Assembly , including the following general objectives, i.e.; “Strengthening effective leadership and governance in mental health; providing comprehensive, integrated and responsive health and social services within a community framework; implementing strategies for promotion and prevention in the field of mental health; strengthening information systems, evidence and research in the field of mental health “. These general objectives are broken down into specific measurable objectives, such as, for example: 80% of countries will have updated their mental health policies and laws by 2016; 80% of countries allocate at least 5% of state health expenditure to mental health in 2020; 80% of countries have at least two national multi-sectorial programs for mental health promotion and protection in operation by 2016 (a universal program and a program targeting vulnerable groups); by 2020, 80% of countries collect and report a minimum core of mental health indicators each year. The Action Plan is based on six cross-cutting principles: universal health coverage, respect for basic human rights, evidence-based practices, a multi-sectorial approach, attention to all life stages, empowerment of people suffering from mental disorders and psychosocial disabilities.
The WHO European Regional Office has recently developed a new European strategy on mental health . It is in line with the WHO Global Action Plan 2013-2020 and the new European Health and Welfare Policy “Health 2020” . The strategy has seven general objectives, i.e.: “Everyone has an equal opportunity to realize mental well-being throughout their lifespan, particularly those who are most vulnerable or at risk ; People with mental health problems are citizens whose human rights are fully valued, respected and promoted ; Mental health services are accessible, competent and affordable, available in the community according to need ; People are entitled to respectful, safe and effective treatment ; Health systems provide good physical and mental health care for all ; Mental health systems work in well coordinated partnership with other sectors ; Mental health governance and delivery are driven by good information and knowledge”. These general objectives are also broken down into specific objectives while distributing tasks between Member States and WHO bodies.
Given the public health importance of mental health disorders and their economic impact, and in light of the health authorities’ awareness of the health issues associated with mental health disorders, one might wonder why mental health is not higher on the political agenda in many/most countries. Could it be, like some authors suggest , a lack of capacity building in the field of mental health and/or some misconception by decision makers of what mental disorders are and/or stigmatization by the population of persons with mental disorders? It seems imperative to inform thoroughly politicians, communities and society at large about the actual disease burden of mental disorders, of their important social and economic costs, but also of the possibilities to reduce this burden through effective and efficient interventions, which do exist. This means that professionals must speak up with arguments based on relevant data. Let’s mention some studies/data that can strengthen the arguments.
• In a priority-setting research  among 422 researchers/ professionals/clinicians/ advocates working in more than 60 countries 25 top mental health intervention challenges were identified. The 5 top challenges, ranked by “disease burden reduction, impact on equity, immediacy of impact and feasibility”, are “a) integrate screening and core packages of services into routine primary care; b) reduce the cost and improve the supply of effective medication; c) provide effective and affordable community based care and rehabilitation; d) improve children’s access to evidence-based care by trained providers in lowand middle-income countries; e) strengthen the mental health component in the training of all health care personnel.”
• The DataPrev Project (Developing the Evidence Base for Mental Health Promotion and Prevention in Europe: a Database of programs and the production of guidelines for policy and practice) funded by the European Commission  “summarizes the evidence for actions to prevent disorders and to promote positive mental well-being  through parenting , at school , at the workplace  and in older age  supported by economic analysis ”.
• Parenting: Stewart-Brown and Schrader-McMillan  analysed 52 systematic reviews evaluating approaches to partenting support. Perinatal programs including antenatal programs, Parenting support programs in infancy and early years and Formal parenting programs with focus on prevention of behavioral problems “were shown to be effective in improving parenting and children’s mental health”. The evidence was not quite conclusive in Parenting support in highest risk groups programs (parents suffering from mental disorders, on drugs, with alcohol abuse and families in which abuse had already occurred).
• Interventions in Schools: Weare and Nind  reviewed 52 systematic-reviews and meta-analyses of mental health in schools. Numerous interventions had a beneficial impact on children, families and communities. The most effective interventions included (among others): teaching skills, focusing on positive mental health; balancing targeted and global approaches; starting with young children; operating over a long period of time. To be effective interventions had to be implemented lege artis.
Table 1. Examples of mental health interventions with return on investment (adapted and simplified according to Knapp ).
• Interventions at workplace: Czabala at al.  reviewed 79 intervention studies essentially aiming at reduction of stress, better coping, mental health improvement, reduction of absenteeism and increased job satisfaction and effectiveness. Conclusive evidence of effectiveness was not straight forward, partially due to lacking outcome evaluation. Yet, Stress Inoculating Training programs showed the most promising approach as long as contextual /organizational factors could be integrated.
• Interventions in older age: Forsman et al.  reviewed 69 prospective controlled trials. Globally psychosocial interventions influenced positively the quality of life of the elderly and their mental health; the interventions also had a significant effect on reducing depressive symptoms.
• Economic aspects of mental health interventions (in high-income countries):McDaid and Park  reviewed 47 studies of “considerable variability in quality”, thus “caution must be exercised in interpreting the results”: parenting and health-visitor-related programs appear most efficient; stress management programs in the workplace are also reported as efficient as well as psychosocial interventions targeting the elderly.
• In Table I we reproduce as examples some interventions that according to Knapp et al.  “pay for” themselves over the long term, but “quick wins” are rare. Some of these effective interventions have a multi-sectorial approach, others are more rooted in clinical practice, highlighting both the key role of public health actors and the no less important role of caregivers.
• Last but not least to be considered are the close links between poverty (to be understood as a multi-dimensional social phenomenon) and common mental disorders : programs investing in education, in strengthening treatment of common mental disorders in primary care, in fighting discrimination and stigmatization, in supporting decent living/working conditions may reduce the risk of mental disorders and improve the well-being of individuals and communities [11, 15, 36].
The mental health of the population is a challenge for health authorities. Its true contribution to the global burden of disease almost as high as the one due to cardiovascular disease and higher than the one due to cancer. Its economical and social costs are huge. The political will to tackle this problem seems to exist if one considers the strategic plans adopted by the ministers of health at the international level. Experts agree (corroborated by strong data) that effective and efficient interventions exist, but more funding is needed. Will the means follow remains an open question.
Yet investing in mental health prevention and promotion programs is justified on the basis of literature studies and experiences from around the world.
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