Nature and specificity of altered cognitive functioning in IBS.

BACKGROUND: It is unknown whether cognitive dysfunction found in patients with irritable bowel syndrome (IBS) was attributable to the different subtypes, ongoing pathophysiological processes, trait characteristics, or psychiatric comorbidity. METHODS: Forty Rome-III patients with IBS (20 diarrhea-predominant [IBS-D] and 20 constipation-predominant [IBS-C]) and 40 age-, sex-, education-matched healthy controls were systematically recruited and compared on their cognitive function with continuous performance test (CPT), Wisconsin Card Sorting Test (WCST) and emotional Stroop test. Beck Anxiety Inventory (BAI), Beck Depression Inventory-II (BDI-II), Patient Health Questionnaire-15 (PHQ-15) and a structured bowel symptom questionnaire were performed to measure anxiety, depressive, somatization, and bowel symptoms, respectively. Psychiatric diagnoses were ascertained with SCID-I (Structured Clinical Interview for DSM-IV Axis I Disorders). KEY RESULTS: Patients with IBS showed significantly increased standard deviation of reaction time (SDRT) (P = .003) on CPT, increased failure to maintain set (FMS) (P=.002), and percentage of perseverative errors (P = .003) on WCST. SDRT did not correlate with illness chronicity or bowel symptoms. FMS correlated with bowel symptom severity. In logistic regression models controlled for BAI, BDI-II, and PHQ-15, SDRT (AOR = 1.08, P = .025), but not FMS (P = .25) or percentage of perseverative errors (P = .24), significantly differentiated IBS from controls. Cognitive function was not significantly different between IBS-C and IBS-D (P > .05), or between pure IBS (n = 22) and IBS with generalized anxiety disorder (GAD) (n = 17) (P > .05). CONCLUSIONS & INFERENCES: Patients with IBS showed attentional and executive function impairment irrespective of subtypes but otherwise heterogeneous in terms of its state-trait correlations and overlap with anxiety comorbidity.

Noneffectiveness of electroacupuncture for comorbid generalized anxiety disorder and irritable bowel syndrome.

BACKGROUND AND AIM: Comorbid generalized anxiety disorder and irritable bowel syndrome are common and therapeutically challenging. We aimed to assess the effectiveness of electroacupuncture in relieving anxiety and bowel symptoms in Chinese adults with this form of comorbidity. METHODS: In a single-blind randomized sham-controlled trial, subjects with comorbid generalized anxiety disorder and irritable bowel syndrome were randomly assigned to receive 10 weekly sessions of electroacupuncture or sham electroacupuncture. Patients were assessed at baseline, immediately after intervention and at 6-week follow-up. Primary outcome was anxiety (7-item Patient Health Questionnaire section for anxiety). Secondary outcomes included bowel symptoms (bowel symptoms questionnaire), depressive symptoms (9-item Patient Health Questionnaire), somatic symptoms (15-item Patient Health Questionnaire), and health-related quality of life (EuroQol-5 Dimensions). RESULTS: Eighty subjects, 40 in each arm, were randomized. All but two in the sham group completed 10 weekly sessions. There was no significant difference in the proportion of patients experiencing significant (≥ 50%) reduction of anxiety symptoms between the two groups immediately after intervention (32.4% vs 21.6%, P = 0.06) and at 6-week follow-up (25.7% in electroacupuncture vs 27% in sham, P = 0.65). Anxiety, depressive symptom, and bowel symptom severity did not differ significantly between electroacupuncture and sham groups. CONCLUSIONS: Findings failed to support the effectiveness of electroacupuncture for comorbid generalized anxiety disorder and irritable bowel syndrome. Further studies are needed to identify effective acupuncture treatment protocols for such comorbidity.