Systematic review with meta-analysis: the prevalence of anxiety and depression in patients with irritable bowel syndrome

Many cross-sectional surveys have reported the prevalence of irritable bowel syndrome (IBS), but there have been no recent systematic review of data from all studies to determine its global prevalence and risk factors. MEDLINE, EMBASE, and EMBASE Classic were searched (until October 2011) to identify population-based studies that reported the prevalence of IBS in adults (≥15 years old); IBS was defined by using specific symptom-based criteria or questionnaires. The prevalence of IBS was extracted for all studies and based on the criteria used to define it. Pooled prevalence, according to study location and certain other characteristics, odds ratios (ORs), and 95% confidence intervals (CIs) were calculated. Of the 390 citations evaluated, 81 reported the prevalence of IBS in 80 separate study populations containing 260,960 subjects. Pooled prevalence in all studies was 11.2% (95% CI, 9.8%-12.8%). The prevalence varied according to country (from 1.1% to 45.0%) and criteria used to define IBS. The greatest prevalence values were calculated when ≥3 Manning criteria were used (14%; 95% CI, 10.0%-17.0%); by using the Rome I and Rome II criteria, prevalence values were 8.8% (95% CI, 6.8%-11.2%) and 9.4% (95% CI, 7.8%-11.1%), respectively. The prevalence was higher for women than men (OR, 1.67; 95% CI, 1.53-1.82) and lower for individuals older than 50 years, compared with those younger than 50 (OR, 0.75; 95% CI, 0.62-0.92). There was no effect of socioeconomic status, but only 4 studies reported these data. The prevalence of IBS varies among countries, as well as criteria used to define its presence. Women are at slightly higher risk for IBS than men. The effects of socioeconomic status have not been well described. Copyright © 2012 AGA Institute. Published by Elsevier Inc. All rights reserved.

Irritable bowel syndrome (IBS) has been associated with high prevalence of psychological disorders. However, it remains unclear whether IBS and each of its subtypes (predominant diarrhea IBS-D, constipation IBS-C, mixed IBS-M) are associated with higher anxiety and depressive symptoms levels. This study aimed to determine the associations of IBS and each of its subtypes with anxiety and/or depression. We conducted a systematic review and meta-analysis using five electronic databases (PubMed, PsychINFO, BIOSIS, Science Direct, and Cochrane CENTRAL). We selected case-control studies comparing anxiety and depression levels of patients with IBS to healthy controls, using standardized rating scales. Outcomes were measured as random pooled standardized mean differences (SMD). Ten studies were included in our analysis (885 patients and 1,384 healthy controls). Patients with IBS had significant higher anxiety and depression levels than controls (respectively, SMD = 0.76, 95 % CI 0.47; 0.69, p < 0.01, I2 = 81.7 % and SMD = 0.80, 95 % CI 0.42; 1.19, p < 0.01, I2 = 90.7 %). This significant difference was confirmed for patients with IBS-C and -D subtypes for anxiety, and only in IBS-D patients for depression. However, other IBS subtypes had a statistical trend to be associated with both anxiety and depressive symptomatology, which suggests a lack of power due to the small number of studies included. Patients with IBS had significantly higher levels of anxiety and depression than healthy controls. Anxiety and depression symptomatology should be systematically checked and treated in IBS patients, as psychological factors are important moderators of symptom severity, symptom persistence, decisions to seek treatment, and response to treatment.

Background/Aims: Postprandial symptoms are common in patients with irritable bowel syndrome (IBS). However, existing studies have come to different conclusions about the role of food in the pathophysiology of IBS. We explored the prevalence of subjective food-related gastrointestinal (GI) symptoms and its relationship to clinical characteristics and psychological factors in IBS. Methods: 330 patients with IBS and 80 healthy volunteers completed a food questionnaire developed for this study. The subjects graded their subjective symptoms after 35 different foods and a food score was obtained by adding the item scores. The relationship between subjective food-related GI symptoms and referral status, IBS subgroup (predominant bowel pattern), sex, anxiety, depression and body mass index (BMI) was estimated. Results: In 209 (63%) of the patients the GI symptoms were related to meals. Gas problems and abdominal pain were the most frequently reported symptoms. Foods rich in carbohydrates, as well as fatty food, coffee, alcohol and hot spices were most frequently reported to cause symptoms. The food score was higher in patients than in controls (p < 0.0001). In the IBS group higher scores were observed in patients with anxiety (p = 0.005), and females (p < 0.001), but the results were unrelated to IBS subgroup, referral status or BMI. The BMI did not differ between groups. Conclusion: A majority of IBS patients consider their symptoms to be related to meals. Especially foods rich in carbohydrates and fat cause problems. Nevertheless, the majority of IBS patients are normal or overweight. Female sex and anxiety predict a high degree of food-related symptoms in IBS.