Words fail me: the verbal IQ deficit in inflammatory bowel disease and irritable bowel syndrome

Background: Many chronic illnesses are accompanied by impaired
cognitive functioning. In people with Inflammatory Bowel
Disease (IBD), there is some research to suggest a decrement in
verbal IQ (VIQ), when compared to people with Irritable Bowel
Syndrome (IBS) and healthy controls. Although this is an important
finding, it is necessary to ensure that such deficits are not due to
methodological problems such as the failure to take into account
pre-morbid functioning.
Methods: A total of 88 people (IBD, N 29; IBS, N 29;
Controls, N 30) completed the Wechsler Abbreviated Scale of
Intelligence (WASI), the Wechsler Test of Adult Reading (WATR),
the Trait Rumination Questionnaire (TRQ), the Center for Epidemiologic
Studies Depression Scale (CES-D), and the General Health
Questionnaire (GHQ-12).
Results: We found evidence of a VIQ decrement in both IBD and
IBS groups when measured against both healthy controls and against
their own pre-morbid IQ scores (WTAR-Predicted WAIS-III IQ
measures). However, the decrement was larger (and of clinical
significance) in the IBD group but not in the IBS group.
Conclusion: Some tentative evidence is presented which suggests
that poor VIQ performance may be due in part to interference from
excessive rumination.

Citation:
Dancey, C.P.; Attree, E.A.; Stuart, G.; Wilson, C.; Sonnet, A. (2009) ‘Words Fail Me: The Verbal IQ Deficit in Inflammatory Bowel Disease and Irritable Bowel Syndrome’ Inflammatory Bowel Diseases 15 (6) pp.852-857.