Western and Carnivorous Dietary Patterns are Associated with Greater Likelihood of IBD Development in a Large Prospective Population-based Cohort

OBJECTIVE

Nutrition plays a role in the development of Crohn's disease [CD] and ulcerative colitis [UC]. However, prospective data on nutrition and disease onset are limited. Here, we analysed dietary patterns and scores in relation to inflammatory bowel disease [IBD] development in a prospective population-based cohort.

METHODS

We analysed 125 445 participants of whom 224 individuals developed de novo UC and 97 CD over a maximum 14-year follow-up period. Participants answered health-related [also prospectively] and dietary questionnaires [FFQ] at baseline. Principal component analysis [PCA] was conducted deriving a-posteriori dietary patterns. Hypotheses-based a-priori dietary scores were also calculated, including the protein score, Healthy Eating Index, LifeLines Diet Score [LLDS], and alternative Mediterranean Diet Score. Logistic regression models were performed between dietary patterns, scores, and IBD development.

RESULTS

PCA identified five dietary patterns. A pattern characterised by high intake of snacks, prepared meals, non-alcoholic beverages, and sauces along with low vegetables and fruit consumption was associated with higher likelihood of CD development (odds ratio [OR]: 1.16, 95% confidence interval [CI]: 1.03-1.30, p = 0.013). A pattern comprising red meat, poultry, and processed meat, was associated with increased likelihood of UC development [OR: 1.11, 95% CI: 1.01-1.20, p = 0.023]. A high diet quality score [LLDS] was associated with decreased risk of CD [OR: 0.95, 95% CI: 0.92-0.99, p = 0.009].

CONCLUSIONS

A Western dietary pattern was associated with a greater likelihood of CD development and a carnivorous pattern with UC development, whereas a relatively high diet quality [LLDS] was protective for CD development. Our study strengthens the importance of evaluating dietary patterns to aid prevention of IBD in the general population.

Whole exome sequencing analyses reveal gene-microbiota interactions in the context of IBD

OBJECTIVE

Both the gut microbiome and host genetics are known to play significant roles in the pathogenesis of IBD. However, the interaction between these two factors and its implications in the aetiology of IBD remain underexplored. Here, we report on the influence of host genetics on the gut microbiome in IBD.

DESIGN

To evaluate the impact of host genetics on the gut microbiota of patients with IBD, we combined whole exome sequencing of the host genome and whole genome shotgun sequencing of 1464 faecal samples from 525 patients with IBD and 939 population-based controls. We followed a four-step analysis: (1) exome-wide microbial quantitative trait loci (mbQTL) analyses, (2) a targeted approach focusing on IBD-associated genomic regions and protein truncating variants (PTVs, minor allele frequency (MAF) >5%), (3) gene-based burden tests on PTVs with MAF <5% and exome copy number variations (CNVs) with site frequency <1%, (4) joint analysis of both cohorts to identify the interactions between disease and host genetics.

RESULTS

We identified 12 mbQTLs, including variants in the IBD-associated genes IL17REL, MYRF, SEC16A and WDR78. For example, the decrease of the pathway acetyl-coenzyme A biosynthesis, which is involved in short chain fatty acids production, was associated with variants in the gene MYRF (false discovery rate <0.05). Changes in functional pathways involved in the metabolic potential were also observed in participants carrying rare PTVs or CNVs in CYP2D6, GPR151 and CD160 genes. These genes are known for their function in the immune system. Moreover, interaction analyses confirmed previously known IBD disease-specific mbQTLs in TNFSF15.

CONCLUSION

This study highlights that both common and rare genetic variants affecting the immune system are key factors in shaping the gut microbiota in the context of IBD and pinpoints towards potential mechanisms for disease treatment.

Intensive playing leads to non-monosymptomatic enuresis in children with low prepulse inhibition

AIM

Parents of children suffering from non-monosymptomatic enuresis (nmE) report their child wetting itself during intensive playing. As children with enuresis are characterized by reduced bladder control (measured as prepulse inhibition (PPI) of startle reflex), the hypothesis suggests that intensive playing leads to further decrease in control and consecutive wetting. Two questions are important: Does PPI change while concentrating? Is this difference more explicit in children with daytime incontinence?

METHODS

Forty-four healthy children, 40 children with nmE and 37 with monosymptomatic enuresis (mE) were examined. PPI was measured while watching DVD and while playing Nintendo's Wii(®) , and calculated as percentage of the native startle response.

RESULTS

All probands showed a relevant decrease in PPI: in relaxed state, the PPI of the controls was 54%; when concentrating, it fell to 34.5% (p = 0.014). The decrease in PPI in mE was from 66% to 51% (p = 0.008), and the decrease in PPI in nmE was from 29% to 21% (p = 0.125).

CONCLUSION

While the decrease in PPI when playing was smallest in the group with nmE, overall PPI level was by far the lowest. The findings confirm the aetiology of enuresis through impaired 'sensori-motor gating' in children with nmE and provide a neurophysiologic correlate for wetting while playing.