Scientific article
Open access

Age at onset in bipolar I affective disorder in the USA and Europe

Publication date2011

Objective. To test for differences in reported age at onset (AAO) of bipolar I affective disorder in clinical samples drawn from Europe and the USA. Methods. Admixture analysis was used to identify the model best fitting the observed AAO distributions of two large samples of bipolar I patients from Europe and USA (n = 3616 and n = 2275, respectively). Theoretical AAO functions were compared between the two samples. Results. The model best fitting the observed distribution of AAO in both samples was a mixture of three Gaussian distributions. The theoretical AAO functions of bipolar I disorder differed significantly between the European and USA populations, with further analyses indicating that (i) the proportion of patients belonging to the early-onset subgroup was higher in the USA sample (63 vs. 25%) and (ii) mean age at onset (±SD) in the early-onset subgroup was lower for the USA sample (14.5 ± 4.9 vs. 19 ± 2.7 years). Conclusions. The models best describing the reported AAO distributions of European and USA bipolar I patients were remarkably stable. The intermediate- and late-onset subgroups had similar characteristics in the two samples. However, the theoretical AAO function differed significantly between the USA and European samples due to the higher proportion of patients in the early-onset subgroup and the lower mean age-at-onset in the USA sample.

Citation (ISO format)
BELLIVIER, Frank et al. Age at onset in bipolar I affective disorder in the USA and Europe. In: The world journal of biological psychiatry, 2011, p. 1–8. doi: 10.3109/15622975.2011.639801
Main files (1)
Article (Published version)
ISSN of the journal1562-2975

Technical informations

Creation11/28/2012 2:12:00 PM
First validation11/28/2012 2:12:00 PM
Update time03/14/2023 7:58:19 PM
Status update03/14/2023 7:58:18 PM
Last indexation01/16/2024 12:59:25 AM
All rights reserved by Archive ouverte UNIGE and the University of GenevaunigeBlack