Psychiatric disorders, comorbidity, and suicidality in Mexico

Background: Prior studies have reported that psychiatric disorders are among the strongest predictors of suicidal behavior (i.e., suicide ideation, plans, and attempts). However, surprisingly little is known about the independent associations between each disorder and each suicidal behavior due to a failure to account for comorbidity. Methods: This study used data from a representative sample of 5782 respondents participating in the Mexican National Comorbidity Survey (2001-2002) to examine the unique associations between psychiatric disorders and suicidality. Results: A prior psychiatric disorder was present in 48.8% of those with a suicide ideation and in 65.2% of those with an attempt. Discrete-time survival models adjusting for comorbidity revealed that conduct disorder and alcohol abuse/dependence were the strongest predictors of a subsequent suicide attempt. Most disorders predicted suicidal ideation but few predicted the transition from ideation to a suicide plan or attempt. Limitations: M-NCS is a household survey that excluded homeless and institutionalized people, and the diagnostic instrument used did not include an assessment of all DSM-IV disorders which would increase the comorbidity discussed here. Conclusions: These results reveal a complex pattern of associations in which diverse psychiatric disorders impact different parts of the pathway to suicide attempts. These findings will help inform clinical and public health efforts aimed at suicide prevention in Mexico and other developing countries. (C) 2009 Elsevier B.V. All rights reserved.