The epidemiology and classification of bulimia nervosa.
BACKGROUND
We sought to determine whether there was empirical support for the diagnostic thresholds of DSM-IV bulimia nervosa (BN) and whether an empirically derived typology resembled the diagnostic categories of DSM-IV.


METHODS
Detailed information about bulimic behaviours were assessed via personal interview in a population-based sample of 1897 Caucasian female twins. We assessed the lifetime prevalence of the component bulimic behaviours and DSM-IV and DSM-III-R BN. Latent class analysis of nine separate bulimic symptoms was used to develop an empirical typology of bulimic behaviour.


RESULTS
Although the lifetime prevalences of bingeing (23.6%) and vomiting (4.8%) were relatively common, DSM-IV BN was distinctly uncommon (0.5%). The criterion that specified the frequency and duration of bingeing and vomiting was an important limiting condition. Analysis of alternative thresholds found little support for the DSM-IV thresholds requiring an average of twice per week for 3 months. Latent class analysis yielded an interpretable four class solution that had little overlap with the DSM-IV typology.


CONCLUSIONS
As in other studies of unselected samples of women, the lifetime presence of bulimic behaviours are relatively high. Our results suggest that the DSM-IV approach to categorizing bulimic behaviour inadequately captures the spectrum of lifetime bulimic behaviours in the general population.
Sullivan
P F
PF
Department of Psychiatry, Virginia Commonwealth University/Medical College of Virginia, Richmond, USA.
Bulik
C M
CM
Kendler
K S
KS
D000328:Adult; D002032:Bulimia / Q000145:classification* / Q000453:epidemiology / Q000235:genetics; D015897:Comorbidity; D003430:Cross-Sectional Studies; D004200:Diseases in Twins / Q000235:genetics / Q000523:psychology; D005260:Female; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data*; D011594:Psychometrics; D014768:Virginia / Q000453:epidemiology