Birth-cohort and dual diagnosis effects on age-at-onset in Brazilian patients with bipolar I disorder
Article first published online: 9 JUL 2009
© 2009 John Wiley & Sons A/S
Acta Psychiatrica Scandinavica
Volume 120, Issue 6, pages 492–495, December 2009
How to Cite
Da Silva Magalhães, P. V., Gomes, F. A., Kunz, M. and Kapczinski, F. (2009), Birth-cohort and dual diagnosis effects on age-at-onset in Brazilian patients with bipolar I disorder. Acta Psychiatrica Scandinavica, 120: 492–495. doi: 10.1111/j.1600-0447.2009.01426.x
- Issue published online: 10 NOV 2009
- Article first published online: 9 JUL 2009
- Accepted for publication May 29, 2009
- bipolar disorder;
- substance use disorders;
- cohort effect
Objective: Substance use disorders and birth-cohort have been associated with an earlier onset in bipolar disorder (BD). This study aimed at evaluating the inter-relations of these factors in age-at-onset in bipolar illness.
Method: Two-hundred and thirty patients with bipolar I disorder were cross-sectionally evaluated. Patients were categorized into four age groups for analysis. Lifetime comorbidity and age-at-onset were derived from the Structured Clinical Interview for DSM-IV.
Results: There was a strong linear association between age group and age-at-onset. Lifetime alcohol and drug use disorders were also associated with age-at-onset. Illicit drug and alcohol use disorders and age group remained significant in the multivariate model. No interactions appeared.
Conclusion: Both age group and dual diagnoses had strong and independent impacts on age-at-onset in out-patients with BD. Substance abuse may be partly accountable for earlier symptom onset, but other features of BD in younger generations are still in need to be accounted for.