The twentieth century has witnessed significant improvements in somatic health in most countries. A number of key public health threats have been eradicated or brought under control under the leadership of WHO. Priority was given to communicable diseases in view of their inherent potential to spreading.

At the present time, a focus on non-communicable diseases and mental health would now appear as the next natural step in public health priorities. In the case of mental health, this is due to the capacity of mental disorders to proliferate not only as a result of complex and multiple biological, psychological but also social determinants. WHO estimates that at any given time 450 million people suffer from some form of mental or brain disorder, including alcohol and substance use disorders. In other words, one in four of the world’s population suffer from different forms of mental, behavioural, and neurological disorders.⁽¹⁾

The World Development Report: investing in health⁽²⁾ and the development of the disability-adjusted life-year for estimating the global burden of disease, including years lost because of disability^(3,4) and the World Health Report 2001, have all raised the awareness of the global burden of mental disorders. Mental disorders already account for more than 13.46 per cent of the GBD. Furthermore, it is estimated that by the year 2015, the GBD from all neuropsychiatric illnesses will reach 14.14 per cent and by 2030, 14.42 per cent. According to WHO, mental disorders accounted for 6 of the 20 leading causes of disability worldwide for the 15-44 age group, the most productive section of the population.⁽¹⁾ While a greater proportion of the burden is found in high-income countries (21.4 per cent) including those with formerly socialist economies (16.4 per cent), low- and middle-income countries are greatly affected and are likely to see a disproportionately large increase in the burden attributable to mental disorders in the coming decades as infectious diseases are brought under better control and as the population ages. The growing burden of mental, neurological, and substance use disorders is exacerbated in low and middle-income countries due to a projected increase in the number of young people entering the age of risk for the onset of certain mental disorders. An estimated 849 000 people commit suicide every year. This figure represents 1.4 per cent of the global burden of disease as estimated using Disability Adjusted Life Years (DALY) methodology. The proportion of the global disease burden due to suicide varies from 0.2 per cent in Africa up to 2.5 per cent in the Western Pacific region. In the European, South East Asian, and Western Pacific regions, this proportion exceeds the world average. Suicide among young people is of significant concern; in some regions, suicide is the third leading cause of death in the age group of 15-35 years. Suicide is the leading cause of death for this age group in China and the second in the European region. Alcohol consumption alone is responsible for 4 per cent of the global disease burden.⁽⁵⁾ In 2000, the global use of alcohol was estimated to have caused 1.8 million deaths or 3.2 per cent of the total deaths from all causes that year. It is estimated that 2.2 million people died from alcohol-related causes in 2005 and increase of 22 per cent from 2000. The population of injecting drug users comprises approximately 10 million people worldwide. Globally, 4-12 per cent of all HIV cases are due to injection drug use, a driving force behind the HIV/AIDS epidemic in many parts of the world.

The economic and social costs of mental disorders fall on societies, governments, people with mental disorders, and their carers and families. Given the long-term nature of mental disorders, the most
evident economic burden is that of direct treatment costs. For example, the most important contributor to direct costs of depression is hospitalization, accounting for around half of the total in the United Kingdom and three-quarters in the United States.⁽⁶⁾ However a common finding from studies of the economic burden of mental disorders in high-income countries is that the ‘indirect’ costs of lost productivity and premature mortality outweigh the ‘direct’ costs of treatment and care.⁽⁷⁾ Three recent mental health economic studies carried out in India have likewise shown that lost production and other time costs greatly exceed the costs of targeted clinical intervention.^{(8, 9 and 10)}

In most countries, families bear a significant proportion of these economic costs because of the absence of publicly funded comprehensive mental health service networks. However, ultimately governments and societies pay a price in terms of reduced national income and increased expenditure on social welfare programmes. Thus, the economic logic for societies and countries is simple: treating mental disorders is expensive but leaving them untreated can be more expensive.

In addition to the obvious suffering caused by mental disorders there is a hidden burden of stigma and discrimination and human rights violations. Rejection, unfair denial of employment opportunities and discrimination in access to services, health insurance, and housing are common as are violations of basic human rights and freedoms, as well as denials of civil, political, economic, and social rights, in both institutions and communities. Much of this goes unreported and therefore the burden remains unquantified. Families and primary care providers also incur social costs, such as the emotional burden of looking after disabled family members, diminished quality of life, social exclusion, stigmatization, and loss of future opportunities for self-improvement.

The WHO survey of mental health resources (Project Atlas) highlighted the huge existent gap between the burden of mental disorders and available resources.^(11,12)