[Early onset depression: prevalence, course, and treatment seeking delay]

To estimate the prevalence of early onset depression in the Mexican population and compare its natural history, comorbidity and treatment latency between early onset and adult onset depression.

The National Survey of Psychiatric Epidemiology (ENEP) is representative of the Mexican urban population aged 18 to 65. The diagnostic instrument is the Composite International Diagnostic Interview (CIDI). Statistical analysis was performed with descriptive and logistic regression analyses, considering the multistage, stratified and weighted sample design of the survey.

Two percent of the Mexican population has suffered from depression as children or adolescents, with an average 7 episodes during their lifetime (compared with 3 episodes for adult onset); the first episode lasted a mean of 31 months (compared with 16 for adult onset) and generally did not receive any treatment.

The longer duration of the first episode and the greater number of lifetime episodes for subjects with early onset is attributed to the lack of early detection and of timely treatment of depression in Mexican youth. The English version of this paper is available at: http://www.insp.mx/salud/index.html.