The Role of Psychological Stress in Inflammatory Bowel Disease: Quality Assessment of Methods of 18 Prospective Studies and Suggestions for Future Research

Abstract

Background: Enquiries among patients on the one hand and experimental and observational studies on the other suggest an influence of stress on inflammatory bowel diseases (IBD). However, since this influence remains hypothetical, further research is essential. We aimed to devise recommendations for future investigations in IBD by means of scrutinizing previously applied methodology. Methods: We critically reviewed prospective clinical studies on the effect of psychological stress on IBD. Eligible studies were searched by means of the PubMed electronic library and through checking the bibliographies of located sources. Results: We identified 20 publications resulting from 18 different studies. Sample sizes ranged between 10 and 155 participants. Study designs in terms of patient assessment, control variables, and applied psychometric instruments varied substantially across studies. Methodological strengths and weaknesses were irregularly dispersed. Thirteen studies reported significant relationships between stress and adverse outcomes. Conclusions: Study designs, including accuracy of outcome assessment and repeated sampling of outcomes (i.e. symptoms, clinical, and endoscopic), depended upon conditions like sample size, participants’ compliance, and available resources. Meeting additional criteria of sound methodology, like taking into account covariates of the disease and its course, is strongly recommended to possibly improve study designs in future IBD research.

Sex-related alterations of gut microbiota composition in the BTBR mouse model of autism spectrum disorder

“…Communication between the gut microbiota (GM) and brain includes several connections such as vagus nerve, gut hormones, microbial metabolites and immune system2. The observation of high co-morbidity between intestinal inflammatory diseases and psychiatric symptoms such as anxiety and stress34 and the frequent occurrence of gastrointestinal dysfunctions in autistic patients5 strongly corroborated the hypothesis of an implication of GM in psychiatric conditions including autistic spectrum disorders (ASD). Pivotal studies revealed improvement in both behavioral and gastrointestinal symptoms of autistic patients upon oral short-term treatment with antibiotics and probiotics67, supporting a role of GM in ASD.…”

Corticotrophin-Releasing Factor, Related Peptides, and Receptors in the Normal and Inflamed Gastrointestinal Tract

“…The cause of symptoms of IBS patients, however, is not clear. Several epidemiological studies have dealt with the influence of (psychological) stress on GI disorders, but interpretation is difficult due to considerable variation in study design and quality (Mawdsley and Rampton, 2005; Hisamatsu et al, 2007; Musial et al, 2008; Camara et al, 2009; Zijdenbos et al, 2009). However, several in vitro and in vivo studies indicate a clear influence of CRF and related peptides on GI functions and inflammation.…”

Microbiome, Gut-Brain-Axis, and Implications for Brain Health

“…Several authors cite the prevalence of psychiatric conditions that often have an associated gastrointestinal condition, such as irritable bowel diseases like Crohn's and ulcerative colitis which can also be correlated with a disturbance in the microbiome (Collins & Bercik, 2012; Wu, 2012; Mawdsley & Rampton, 2005; Camara, Ziegler, Begre, Schoepfer, & von Kanel, 2009; Mawdsley & Rampton, 2006). For example, in order to study associations between eating disorders and the microbiome, inpatients diagnosed with anorexia were compared with healthy controls (Klienman, 2015).…”