Global Distribution of Mental Disorder Prevalence

Where is the mental health burden the heaviest?

To understand how mental health challenges are spread across the world, We started by visualizing the overall prevalence of mental disorders geographically. Using a choropleth map, We mapped each country's prevalence rate from 1990 to 2019, with color gradients from green (low prevalence) to red (high prevalence).

This map allows users to directly explore both spatial and temporal patterns — filtering by year to see how the burden of mental disorders evolves across time.

What this visualization reveals is a striking and stable pattern: African and South American regions have consistently experienced higher prevalence rates of mental disorders, while East Asian countries (such as China, Japan, and Singapore) maintain much lower levels over time. Despite changes in healthcare, environment, or social factors, the global distribution remains remarkably steady, highlighting persistent geographical inequalities in mental health challenges.

Mental Disorder Type Trends Over Time

Knowing how much is only part of the story — what about the "what"?

Total prevalence tells us where the problem is severe — but not what types of mental disorders people are struggling with. To break this down, We turned to a dynamic pie chart visualization that shows the composition of different mental disorder types (Anxiety, Bipolar, Depressive, Eating, Schizophrenia) within the global population for each year.

Rather than focusing on raw numbers, this visualization highlights proportions — helping us see whether the internal structure of mental health challenges is shifting over time. An interactive year slider allows users to either select a specific year or play through all years to observe trends.

The insight is clear: depressive disorders and anxiety disorders dominate the global landscape across all years, consistently taking up the majority share. Meanwhile, disorders like eating disorders and schizophrenia remain relatively rare in the global context. Interestingly, despite the growing attention to mental health in recent years, the internal composition of disorder types has changed very little — reinforcing the idea that depression and anxiety have long been, and continue to be, the most prevalent mental health challenges worldwide.

Disease Prevalence vs. Burden

By comparing the global prevalence of each mental disorder with its corresponding DALY value, a scatterplot helps reveal how some disorders may be widespread but relatively less debilitating, while others—though less common—may have a disproportionate impact. The steepness of the trend line or the clustering of points indicates how DALYs change with prevalence:

Depression and Anxiety disorders show a strong linear correlation, indicating that their widespread prevalence proportionally contributes to a significant global disease burden. Depressive disorders, with higher prevalence rates, show an even steeper increase in DALYs, which highlights their severe impact on quality of life. Bipolar disorders, despite lower prevalence compared to anxiety and depression, still result in substantial DALYs due to their chronic and disabling nature. Schizophrenia disorders, though rare, display a disproportionate impact on DALYs, which shows how it may have a high disease burden for affected individuals.

World DALY Trends Over Time (1990-2019)

To capture how the burden of different mental disorders has evolved over time, a line chart was used to visualize DALY trends from 1990 to 2019. All conditions besides depression have been steady without decreasing despite growing awareness, while depression has shown a slight fluctuation decrease since 2010. Anxiety and Depressive disorders, with high DALYs rates, suggests that these conditions remain pressing global health challenges despite increased awareness and interventions.

Global DALY Distribution

Lastly, a bar graph and geographical heat map of DALYs across countries was used to visualize the global distribution of mental health burdens. Interestingly, high-income countries tend to report higher DALYs, which possibly reflects both better diagnostic/reporting systems and societal pressures. Meanwhile, low- and middle-income countries, particularly in parts of Africa and Southeast Asia, despite Uganda, may show artificially low burdens due to underreporting and limited data. Some regions like Northern Europe and Australia also exhibit high burden levels despite strong healthcare systems, which indicates the complex, multifactorial nature of mental health challenges.

Changes in Treatment Gaps By Year

By using the stacked area chart of Changes in treatment gaps by year, the visualization presents the trend of global mental illness treatment. Analyzing the data from 2002 to 2017, we found that the treatment gap, while briefly improving, remains stark overall, with the chart showing that in most years, the largest proportion of the population was consistently "untreated," most notably in 2002, 2006, 2012, and 2017.

It is worth noting that there were temporary reductions in the treatment gap in 2007 and 2015, which may reflect the success of specific intervention policies or programs, but the overall trend still shows instability and imbalance in the mental health services system. In addition, the ratio of "potentially appropriate treatment" to "other treatment" is consistently low, reflecting the constraints of multiple factors such as access to services, resource allocation, and standards of care.

Comparison of Treatment By Country

To understand the treatment gaps between different countries, we used the stacked bar chart to show the treatment of mental illness in different countries between 2002 and 2017, clearly revealing significant differences in global treatment coverage. Some high-income countries, such as Murcia, Spain, the United States, Israel, and high-income countries as a whole, have relatively low rates of untreated people, indicating higher access to mental health services in these countries. In low - and middle-income countries such as Lebanon, Iraq, Nigeria, Mexico and Colombia, the proportion of people "not receiving treatment" exceeds 90%, reflecting poor treatment resources and access to services. Overall, the visualization highlights regional inequalities in mental health services around the world, providing an important basis for identifying priority areas for intervention and developing policy.

Trends in Global Prevalence of Mental Disorders

To explore trends in global prevalence of mental disorders between 1988 and 2020, we created a series of line charts covering four major mental disorders: anxiety disorders, depressive disorders, eating disorders, and schizophrenia. However, the overall trend in disease burden remains almost unchanged, underscoring that mental illness continues to be a persistent global issue requiring urgent attention and sustained action.

We also observed that North America (represented by the red line) consistently appears at the top across all graphs. This indicates that this region has borne the highest burden of mental illness over an extended period. As a result, our subsequent analysis will focus more closely on the state of mental health within North American countries.

Widespread Mental Strain

The data reveals that among the U.S. population, depressive symptoms are most commonly expressed as low energy and sleep problems. Nearly 10% of people report feeling low energy almost every day, while more than 1/3 experience it every few days. Similarly, sleep disturbances are a widespread concern, with over 20% of respondents struggling with sleep on a regular basis. These findings highlight not only the prevalence of emotional distress but also the often-overlooked burden carried by individuals who may not meet the clinical threshold for depression yet still face significant mental strain. Addressing this subtle but pervasive challenge is crucial for effective public health interventions.

Trends in Anxiety, Depression, and Schizophrenia

Over the past three decades, anxiety and depressive disorders have become the most prevalent mental health conditions in the U.S. Anxiety disorders, affecting the largest share of the population, saw a sharp rise in the late 1990s, peaking around 2000 at nearly 6.7%. Although the rate declined in the years following, it began climbing again as 2020 approached. Depressive disorders, the second most common, steadily increased from under 4% in 1990 to about 4.5% by the early 2000s and have remained relatively stable since then. Together, these two disorders impact millions of Americans annually, presenting a significant public health concern.

Schizophrenia, while affecting a smaller portion of the population compared to anxiety and depression, also follows an important trend. From 1990 to around 2005, the share of the U.S. population with schizophrenia rose slightly from 0.43% to a peak of about 0.46%, followed by a gradual decline in subsequent years. Despite its lower prevalence, the U.S. reports the highest rate of schizophrenia among all countries, highlighting the need for continued research, awareness, and support for those affected by this condition.