GAD more common in high-income countries
Cross-sectional analysis of global data indicated DSM-5 generalized anxiety disorder was more common, particularly in high-income countries.
“Understanding of generalized anxiety disorder (GAD) has lagged behind understanding of other anxiety disorders. Since its introduction in DSM-III, the GAD diagnosis has undergone frequent substantial revision, challenging efforts to accumulate a knowledge base for the disorder,” Ayelet Meron Ruscio, PhD, of University of Pennsylvania, Philadelphia, and colleagues wrote.
To establish epidemiologic data on DSM-5 GAD and assess international differences in prevalence, course, correlates and impact, researchers analyzed data from the World Health Organization World Mental Health Survey Initiative for 147,261 adults. Cross-sectional general population surveys were conducted in 26 countries via in-person interviews from 2001 to 2012.
Combined life prevalence of DSM-5 GAD was 3.7%, 12-month prevalence was 1.8% and 30-day prevalence was 0.8%.
Prevalence estimates significantly varied among countries, with lifetime prevalence highest in high-income countries (5%), followed by middle-income countries (2.8%) and low-income countries (1.6%).
Researchers found that GAD typically began in adulthood and persisted over time, though onset was later and clinical course was more persistent in lower-income countries.
Lifetime comorbidity was high (81.9%), particularly for mood (63%) and other anxiety disorders (51.7%).
Severe role impairment was common across age ranges, particularly in high-income countries.
Approximately half of individuals sought treatment (49.2%), especially those with severe role impairment (59.4%), comorbid disorders (55.8%) or living in high-income countries (59%).
“Using data from 26 countries, we showed that DSM-5 GAD is a common disorder associated with considerable comorbidity and functional impairment,” the researchers wrote. “The disorder typically begins in adulthood, although its onset is later and its course is more persistent in less developed countries. Although GAD is found in similar subgroups within the countries examined, it is more prevalent and impairing in high-income than in low or middle-income countries. Probing the mechanisms underlying these cross-national differences will advance understanding of GAD and inform debates regarding its validity and global relevance.” – by Amanda Oldt
Disclosure: Ruscio reports no relevant financial disclosures. Please see the study for a full list of relevant financial disclosures.