Without mental health, there can be no true physical health. These words were spoken half a century ago by Dr Brock Chisholm, psychiatrist and first Director-General of the World Health Organization. Yet today, and in spite of the COVID-19 pandemic shining a light on its importance, mental health continues to be neglected by all countries of the world.

Mental, neurological and substance (MNS) disorders include a diverse range of diseases and conditions such as depression, schizophrenia, anxiety, dementia, and alcohol and drug abuse, among many others. It’s estimated that five to 20 percent of the global population is living with such disorders at any given time.

This broad estimate illustrates how mental health has been ignored and thus underfunded worldwide. National governments spend an average of just 2% of their health budgets on mental health, and this figure is even lower in developing countries, where most people living with a mental disorder are never diagnosed. Of those who are, only 15 to 25 percent receive any kind of treatment. Hundreds of millions of people lack access to the mental health support and services they need.

Accessing treatment is not only a problem for developing countries. Although the number of mental health cases in England is estimated at 8.3 million annually, only 2.8 million people are in contact with mental health services. In the US, where nearly 20 percent of the population lives with a mental disorder, 56 percent are not able to access treatment.

The main barrier in countries of all income levels is cost, as many health insurance schemes – both public and private – do not adequately cover mental health care, leaving people living with MNS disorders to pay out-of-pocket for treatment. Other factors, such as the stigmatization of people living with mental health disorders, also prevent many people from seeking care. This not only translates into poor outcomes for mental and general health but also implies massive economic losses for countries and the global economy.

Mental, neurological and substance abuse (MNS) disorders are the leading cause of global disability, responsible for 35.9% of disabled years. Globally, the cost of all MNS disorders has been estimated at US$ 8.5 trillion and is projected to double by 2030. The global economy loses more than US$ 1 trillion per year due to depression and anxiety alone. Figures are similar for dementia: in 2015, the total global societal cost of dementia was estimated to be US$ 818 billion, equivalent to 1.1% of global GDP – and this figure is expected to skyrocket along with the number of people living with dementia, from a projected 82 million in 2030 to 152 in 2050.

Some studies have evaluated costs at national levels. For instance, a February 2022 study by the London School of Economics estimated the annual costs of mental health conditions in the UK to be almost £118 billion, with the majority of costs coming through lost employment and informal care costs. This estimate does not include dementia, nor presenteeism and absenteeism in the workplace, which would raise the cost of mental disorders in the UK much higher.

The economic toll can also be attributed in part to the fact that people with MNS disorders tend to live shorter lives. Overall, people living with severe mental disorders have a 10- to 25-year reduction in their life expectancy, compared to people without these conditions. The causes of death are most often due to other noncommunicable diseases (NCDs), like cancer, heart disease and stroke, chronic kidney disease and diabetes, which affect more than two-thirds of people living with an MNS disorder.

It has been shown that poor mental health can increase the likelihood that a person will have an unhealthy diet, get inadequate exercise, or use tobacco or alcohol, which are all major risk factors for NCDs. Comorbidities due in part to mental health are costing billions to the economy healthcare costs and productive years lost, causing millions of early preventable deaths, with the highest-burden falling upon the poorest and most marginalised populations in all countries.

The same applies to infectious diseases as for NCDs. For instance, a growing number of studies have linked mental health disorders with a higher risk of serious COVID-19 outcomes. One US study found that the risk of death from COVID-19 went up by 50 percent for those living with mental illness, putting populations at increased risk during the pandemic. Failure to invest in mental health will threaten our health and health systems in future pandemics.

However, it’s not too late to take action. Many mental health conditions can be effectively treated – or better yet, prevented. The benefit-to-cost ratio of investments to increase treatment rates for common MNS disorders is between 2.3 and 5.7 to 1, and the return on prevention measures is even higher. Cost-effective prevention measures include changing workplace cultures to promote and protect mental health, offering different opportunities for exercise for all age groups, and anti-bullying programmes as an integral part of school curriculums. Half of all mental disorders begin by the age of 14 and three-quarters by mid-20s, which means a lifecourse approach to mental health is critical.

MNS disorders are a major public health problem with severe economic and health consequences for all of society, and governments must urgently prioritize investment in treating and preventing them. It’s an investment that promises great returns – economically, for our health, and for pandemic preparedness and resilience.

This article was originally published on NCDA's LinkedIn.