By Jean Balchin 13/04/2018

According to a study published in Child and Adolescent Psychiatry and Mental Health, although global rates of mental disorders in children have remained stable over time, the decline of infectious diseases will place mental disorders among the main causes of disease in children aged 4-15 years.

In the study, Marie-Laure Baranne and Bruno Falissard at INSERM, France describe the prevalence of mental disorders among children aged 5-14 years in each of the six regions of the World Health Organisation – Africa, the Americas, South-East Asia, Europe, the Easter Mediterranean, and the West Pacific Region. Baranne and Falissard found that even in emerging regions, the prevalence of mental disorders is high and constant over time.

According to Baranne,

“We found that the prevalence of mental disorders in young people remained stable between 2000 and 2015, which suggests that mental disorders are not decreasing in young people despite the global improvement of their physical health.

In the future, the decrease of other, preventable diseases, such as diabetes, will lead to an increase in the importance of treating mental disorders for public health.”

In 2000 in the Americas and Europe, mental disorders ranked third among the causes of disability adjusted life years (DALYs). DALYs refer to the lost years of a healthy life due to disease or disability. Effectively, they function as a measure of disease burden, and enable one to gauge the impact of a health problem in a population.

For this study, mental disorders were divided into 13 subcategories: major depressive disorders, dysthymia, bipolar disorders, schizophrenia, alcohol use disorders, drug use disorders, anxiety disorders, eating disorders, autism spectrum disorders (reported in the GBD database as Autism and Asperger syndrome), conduct disorders, attention-deficit/hyperactivity disorder (ADHD), idiopathic intellectual disability, and other mental and behavioural disorders.

The authors found that by 2015, mental disorders had reached second place as causes of DALYs in the Americas and Europe, while the impact of infectious diseases (such as parasitic diseases and neonatal conditions) decreased.

The change from infectious diseases to mental disorders as the main cause of DALYs in children is known as an epidemiological transition. The impact of mental disorders on child health is going to become more important in the future as more countries make the transition from infection diseases to mental disorders as major causes of ill-health, according to the authors.

Marie-Laure Baranne said:

“Our study is intended as an urgent signal of alarm to international public health institutions and policy-makers. Given the impact of these mental disorders in the long term, organising a global policy to address this issue requires careful preparation.”

In most regions, four mental disorders ranked among the 20 diseases associated with the most DALYs:

  1. Conduct disorders
  2. Anxiety disorders
  3. Major depressive disorders
  4. Austism-Asperger syndrome.

Among boys, the most common mental disorders associated with DALYs were conduct disorders, autism-Asperger syndrome and anxiety disorders. Among girls they were anxiety disorders, conduct disorders and major depressive disorder.

Moreover, the authors also noticed an effect of income. Regions with the highest gross domestic product (GDP), such as in Western Europe, were found to have fewer problems with infectious diseases and more problems with mental disorders.

The authors note that mental disorders “are still considered mysterious in most societies because they are supposed to affect the mind more than the body,” going on to say they “are often neglected and even denied by populations.”

“Policy-makers are thus often tempted to cut spending in this domain. This is even truer for child and adolescent psychiatry, where some pathologies, such as conduct disorders, are considered deviance rather than a health problem that requires compassion and care.”

One should keep in mind however that calculation of DALYs relies on parameters that are only known as approximations. Moreover, they are based on multiple sources of information containing potential errors that may introduce some uncertainty into estimates.

You can read more about this study here.

Image: Photo by Hannah Tasker on Unsplash