Worldwide Prevalence and Disability From Mental Disorders Across Childhood and Adolescence: Evidence From the Global Burden of Disease Study

Abstract

Importance: The period from childhood to early adulthood involves increased susceptibility to the onset of mental disorders, with implications for policy making that may be better appreciated by disaggregated analyses of narrow age groups.

Objective: To estimate the global prevalence and years lived with disability (YLDs) associated with mental disorders and substance use disorders (SUDs) across 4 age groups using data from the 2019 Global Burden of Disease (GBD) study.

Design, setting, and participants: Data from the 2019 GBD study were used for analysis of mental disorders and SUDs. Results were stratified by age group (age 5 to 9, 10 to 14, 15 to 19, and 20 to 24 years) and sex. Data for the 2019 GBD study were collected up to 2018, and data were analyzed for this article from April 2022 to September 2023.

Exposure: Age 5 to 9 years, 10 to 14 years, 15 to 19 years, and 20 to 24 years.

Main outcomes and measures: Prevalence rates with 95% uncertainty intervals (95% UIs) and number of YLDs.

Results: Globally in 2019, 293 million of 2516 million individuals aged 5 to 24 years had at least 1 mental disorder, and 31 million had an SUD. The mean prevalence was 11.63% for mental disorders and 1.22% for SUDs. For the narrower age groups, the prevalence of mental disorders was 6.80% (95% UI, 5.58-8.03) for those aged 5 to 9 years, 12.40% (95% UI, 10.62-14.59) for those aged 10 to 14 years, 13.96% (95% UI, 12.36-15.78) for those aged 15 to 19 years, and 13.63% (95% UI, 11.90-15.53) for those aged 20 to 24 years. The prevalence of each individual disorder also varied by age groups; sex-specific patterns varied to some extent by age. Mental disorders accounted for 31.14 million of 153.59 million YLDs (20.27% of YLDs from all causes). SUDs accounted for 4.30 million YLDs (2.80% of YLDs from all causes). Over the entire life course, 24.85% of all YLDs attributable to mental disorders were recorded before age 25 years.

Conclusions and relevance: An analytical framework that relies on stratified age groups should be adopted for examination of mental disorders and SUDs from childhood to early adulthood. Given the implications of the early onset and lifetime burden of mental disorders and SUDs, age-disaggregated data are essential for the understanding of vulnerability and effective prevention and intervention initiatives.

Figure 1.. Global Prevalence of Mental Disorders by Sex and Age Group From Age 5 to 24 Years

Anxiety disorders included the combined estimate of all subtypes of International Classification of Diseases anxiety disorders; depressive disorders, major depressive disorder and dysthymia; eating disorders, anorexia nervosa and bulimia nervosa; intellectual disability, idiopathic developmental intellectual disability, comprising intellectual disability from any unknown source after all other sources of intellectual disability are accounted for; and other mental disorders, residual category corresponding to an aggregate group of personality disorders. Data were not modeled by the Global Burden of Disease study before age 10 years for schizophrenia, bipolar disorder, drug use disorders, and other mental disorders; for conduct disorder, only cases prior to age 18 years are modeled. For attention-deficit/hyperactivity disorder (ADHD), no incidence is assumed in the Global Burden of Disease study from age 12 years onward.^, The dotted horizontal lines indicate the mean combined prevalence for female and male children and youth across all age strata. The shaded areas indicate 95% uncertainty intervals.

Figure 2.. Years Lived With Disability (YLDs) From Mental and Substance Use Disorders, Age 5 to 24 Years

Number of YLDs is age specific rather than cumulative, ie, YLDs from the older age groups do not incorporate the YLDs recorded for the younger age groups. Anxiety disorders included the combined estimate of all subtypes of International Classification of Diseases anxiety disorders; depressive disorders, major depressive disorder and dysthymia; eating disorders, anorexia nervosa and bulimia nervosa; intellectual disability, idiopathic developmental intellectual disability, comprising intellectual disability from any unknown source after all other sources of intellectual disability are accounted for; and other mental disorders, residual category corresponding to an aggregate group of personality disorders. Data were not modeled by the Global Burden of Disease study before age 10 years for schizophrenia, bipolar disorder, drug use disorders, and other mental disorders; for conduct disorder, only cases prior to age 18 years are modeled. For attention-deficit/hyperactivity disorder, no incidence is assumed in the Global Burden of Disease study from age 12 years onward.^,

Figure 3.. Ranking of Mental Disorders and Substance Use Disorders According to Nonfatal Disability Expressed as Years Lived With Disability (YLDs) by Age Group, Both Sexes Combined

In each age group, the column order reflects the rank within the group of mental disorders, while the number inside each cell reflects the overall rank among all causes within the 2019 Global Burden of Disease study. Gray cells marked with not applicable (NA) show disorders for which burden was not estimated within the age group. Anxiety disorders included the combined estimate of all subtypes of International Classification of Diseases anxiety disorders; depressive disorders, major depressive disorder and dysthymia; eating disorders, anorexia nervosa and bulimia nervosa; intellectual disability, idiopathic developmental intellectual disability, comprising intellectual disability from any unknown source after all other sources of intellectual disability are accounted for; and other mental disorders, residual category corresponding to an aggregate group of personality disorders.^, ADHD indicates attention-deficit/hyperactivity disorder.

Figure 4.. Proportion of Years Lived With Disability (YLDs) According to Age Group and Sex for Mental Disorders, Cardiovascular Disease, and Diabetes, Neoplasms, and Unintentional Injuries

Female children and youth are shown to the left of 0 and male children and youth to the right of 0. Gray shading indicates age brackets of interest (age 5 to 9 years, 10 to 14 years, 15 to 19 years, and 20 to 24 years). Data were not modeled by the Global Burden of Disease study before age 10 years for schizophrenia, bipolar disorder, drug use disorders, and other mental disorders; for conduct disorder, only cases prior to age 18 years are modeled. For attention-deficit/hyperactivity disorder, no incidence is assumed in the Global Burden of Disease study from age 12 years onward.