Genetic polymorphisms associated with smoking behaviour predict the risk of surgery in patients with Crohn's disease

Assessing Progression of Biologic Therapies Based on Smoking Status in Patients With Crohn's Disease

BACKGROUND

Active smoking is a well-established risk factor for developing Crohn's disease (CD) and negatively impacts overall disease progression. Patients who start or continue smoking after CD diagnosis are at risk for poor outcomes, higher therapeutic requirements, and have higher rates of relapse. However, it remains unclear if the exposure to smoking leads to increased sequencing through treatment therapies, especially biologics.

METHODS

The Study of Prospective Adult Research Cohort with IBD (SPARC IBD) registry has been collecting patient-reported outcomes data in real-time, as well as laboratory, endoscopic, and pathologic samples from 17 tertiary referral centers since 2016. In this study, we conducted a retrospective review of the SPARC clinical registry collected between December 2016 and January 2021 from 1 participating site, the University of Maryland School of Medicine's Inflammatory Bowel Disease Program. A total of 619 patients were enrolled in the SPARC IBD database. Four hundred twenty-five patients with CD were included for initial review of completeness of data; of these, 144 patients were excluded due to missing data on smoking status and/or biologic treatment, resulting in a final cohort of 281 patients. We collected and analyzed baseline demographic and clinical characteristics. The final cohort was categorized into 3 exposure groups: current, former, and never smokers. Our outcome of interest was number biologics used, categorized into 3 groups: 0, 1, or ≥2 biologics.

RESULTS

One hundred seventy-two never smokers, 70 former smokers, and 39 current smokers were identified. Current, former, and never smokers had no statistically significant differences in number of biologics used (ie, biologic sequencing). However, statistically significant independent risk factors for increased sequencing of biologics were identified. These risk factors included female sex, ileocolonic disease location, younger age at diagnosis, and prolonged disease duration; none of these factors remained significant in adjusted analyses.

CONCLUSION

To date, this is the first study assessing the association of smoking and sequencing of biologics. Although current or former smokers were not found to sequence through more biologics when compared with never smokers, smoking is a well-established risk factor for poor health outcomes, and efforts should be made to counsel patients to quit. Further, additional research must be done to stratify risk to patients based on amount of tobacco exposure.

Defining Interactions Between the Genome, Epigenome, and the Environment in Inflammatory Bowel Disease: Progress and Prospects

Recent advances in our understanding of the pathogenesis of inflammatory bowel disease (IBD) have highlighted the complex interplay between the genome, the epigenome, and the environment. Despite the exciting advances in genomics that have enabled the identification of over 200 susceptibility loci, these only account for a small proportion of the disease variance and the estimated heritability in IBD. It is likely that gene-environment (GxE) interactions contribute to "missing heritability" and these may act through epigenetic mechanisms. Several environmental factors, such as the microbiome, nutrition, and tobacco smoking, induce alterations in the epigenome of children and adults, which may impact disease susceptibility. Other mechanisms for GxE interactions are also directly pertinent in early life. We discuss a model in which environmental factors imprint disease risk in a window of susceptibility during infancy that may contribute to later disease onset, whereas other elements of the exposome act later in life and contribute directly to the pathogenesis and course of the disease. Understanding the mechanisms underlying GxE interactions may provide the basis for new therapeutic targets or preventative strategies for IBD.

Because I'm happy - positive affect and its predictive value for future disease activity in patients with inflammatory bowel diseases: a retrospective cohort study

Background

While the detrimental impact of negative emotions on the clinical course of inflammatory bowel disease (IBD) and quality of life has been extensively investigated, evidence for a potential impact of positive emotions is scarce.

Objectives

We aim to analyse contributing factors of positive affect and their predictive value for disease course in IBD patients.

Design

In this retrospective cohort study, epidemiological, psychosocial and IBD disease characteristics of Swiss IBD cohort study patients were analysed longitudinally.

Methods

Epidemiological, psychosocial and disease characteristics were extracted from the database of the Swiss IBD cohort study. Participants' positive emotions were assessed cross-sectionally with the seven-item Marburg questionnaire (range 1-6) addressing positive affect in different aspects of daily life. Predictors of positive emotions were identified by linear regression. The quantitative longitudinal impact of positive emotions on the further disease course was analysed using a multivariable Cox proportional hazards model.

Results

Among 702 IBD patients, those reporting more positive emotions were found to have significantly less intense medical treatment, less pain and fewer depressive symptoms (p < 0.05). A higher percentage of variability in positive emotions was explained by pain (36%) and depressive symptoms (13%) than by epidemiological characteristics (0.3%), or characteristics of IBD and its treatment (2.4%). Patients with higher levels of positive emotions (score > 3.5) experienced longer flare-free survival, also after adjusting for confounders (adjusted hazard ratio: 0.39, p < 0.05).

Conclusions

The absence of pain and depressive symptoms were the strongest drivers for high positive affect. Higher scores of positive affect were associated with longer disease-free survival in IBD patients.

Stem Cell-Based Therapies for Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic, relapsing disease that severely affects patients’ quality of life. The exact cause of IBD is uncertain, but current studies suggest that abnormal activation of the immune system, genetic susceptibility, and altered intestinal flora due to mucosal barrier defects may play an essential role in the pathogenesis of IBD. Unfortunately, IBD is currently difficult to be wholly cured. Thus, more treatment options are needed for different patients. Stem cell therapy, mainly including hematopoietic stem cell therapy and mesenchymal stem cell therapy, has shown the potential to improve the clinical disease activity of patients when conventional treatments are not effective. Stem cell therapy, an emerging therapy for IBD, can alleviate mucosal inflammation through mechanisms such as immunomodulation and colonization repair. Clinical studies have confirmed the effectiveness of stem cell transplantation in refractory IBD and the ability to maintain long-term remission in some patients. However, stem cell therapy is still in the research stage, and its safety and long-term efficacy remain to be further evaluated. This article reviews the upcoming stem cell transplantation methods for clinical application and the results of ongoing clinical trials to provide ideas for the clinical use of stem cell transplantation as a potential treatment for IBD.

Depressive Symptoms Predict Clinical Recurrence of Inflammatory Bowel Disease

BACKGROUND

Inflammatory bowel disease (IBD) patients are at high risk for depression, and depression has been shown to affect disease course. We examined interrelations between depression, genetic risk factors for depression, and IBD flares.

METHOD

In 1973 patients (1137 Crohn's disease, 836 ulcerative colitis) of the Swiss IBD Cohort Study (SIBDCS), depressive status (hospital anxiety and depression subscale for depression, HADS-D ≥11) was assessed on a yearly basis. We investigated the impact of depression on IBD-relevant clinical outcomes in Cox proportional hazards models. We used active disease (CDAI ≥150 or MTWAI ≥10) and 2 published composite flare definitions-FNCE (physician-reported flare, nonresponse to therapy, new complication, or extraintestinal manifestation) and AFFSST (active disease, physician-reported flare, fistula, stenosis, and new systemic therapy)-as clinical end points. Additionally, 62 preselected single nucleotide polymorphisms (SNPs) were screened for cross-sectional associations with depression, and if present, their predictive value for future depression and clinical deterioration was assessed.

RESULTS

Depression was a strong risk factor for disease-related end points, including active disease (adjusted hazard ratio [aHR], 3.55; P < 0.001), AFFSST (aHR, 1.62; P < 0.001), and FNCE (aHR, 1.35; P = 0.019). The SNP rs2522833 was significantly associated with depression at enrollment (q = 0.059). The TC allele of rs588765 was negatively associated with the presence of depression at enrollment (q = 0.050) and after enrollment (aHR, 0.67; P = 0.035) and with fewer active disease states (aHR, 0.72; P = 0.045) during follow-up.

CONCLUSION

In IBD, depressive symptoms and inflammatory activity are intimately related. Depressive symptoms were a strong predictor of clinical deterioration, and genetic markers may play a role in this relationship.

Genotype-phenotype associations of polymorphisms within the gene locus of NOD-like receptor pyrin domain containing 3 in Swiss inflammatory bowel disease patients

Background

Genetic variations within the regulatory region of the gene encoding NOD-like receptor pyrin domain containing 3 (NLRP3) have been associated with Crohn’s Disease (CD). NLRP3 is part of the NLRP3-inflammasome that mediates the maturation of IL-1β and IL-18. Carrying the major allele of the single nucleotide polymorphisms (SNPs) rs10733113, rs4353135 and rs55646866 is associated with an increased risk for CD. We here studied the impact of these polymorphisms on clinical characteristics in patients of the Swiss IBD Cohort Study (SIBDCS).

Methods

We included 981 Crohn’s disease (CD) patients and 690 ulcerative colitis (UC) patients of the SIBDCS. We analyzed whether three CD-associated NLRP3 polymorphisms have an impact on the clinical disease course in these patients.

Results

In CD patients presence of the major allele (G) of rs10733113 was associated with less surgeries and lower maximal CDAI and a similar trend was observed for rs55646866 and rs4353135. Presence of the major allele of all three SNPs was negatively correlated to maximal CDAI. In UC patients homozygous genotype for the major allele (CC) for rs55646866 was associated with a higher age at diagnosis and a higher MTWAI index. Homozygous genotype for the major allele of all three polymorphisms was associated with a higher number of ambulatory visits and longer hospital stays.

Conclusions

In CD patients presence of the major allele of all three polymorphisms was associated with markers of a less severe disease course, while in UC the homozygous genotype for all major alleles suggested a more severe disease activity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-01880-9.

Passive Smoking Increases the Risk for Intestinal Surgeries in Patients With Crohn's Disease

BACKGROUND

Despite substantial evidence on the negative effect of active smoking, the impact of passive smoking on the course of Crohn's disease (CD) remains largely unclear. Our aim was to assess passive smoking as a risk factor for intestinal surgeries in CD.

METHODS

The study was conducted in a university-based, monocentric cohort of 563 patients with CD. Patients underwent a structured interview on exposure to passive and active smoking. For clinical data, chart review was performed. Response rate was 84%, leaving 471 cases available for analysis. For evaluation of the primary objective, which was the impact of exposure to passive smoking on the risk for intestinal surgery, only never actively smoking patients were included.

RESULTS

Of 169 patients who never smoked actively, 91 patients (54%) were exposed to passive smoking. Exposed patients were more likely to undergo intestinal surgery than nonexposed patients (67% vs 30%; P < 0.001). Multivariate Cox regression analysis revealed that passive smoking was an independent risk factor for intestinal surgeries (hazard ratio, 1.7; 95% CI, 1.04-2.9; P = 0.034) after adjustment for ileal disease at diagnosis (hazard ratio, 2.9; 95% CI, 1.9-4.5; P < 0.001) and stricturing or penetrating behavior at diagnosis (hazard ratio, 1.9; 95% CI, 1.2-3.1; P = 0.01). Passive smoking during childhood was a risk factor for becoming an active smoker in later life (odds ratio, 2.2; 95% CI, 1.5-3.2; P < 0.001).

CONCLUSION

Passive smoking increases the risk for intestinal surgeries in patients with CD.

Abdominal pain in patients with inflammatory bowel disease: association with single-nucleotide polymorphisms prevalent in irritable bowel syndrome and clinical management

BACKGROUND

Abdominal pain is a frequent symptom in patients with inflammatory bowel disease (IBD) including Crohn's disease (CD) and ulcerative colitis (UC). Pain can result from ongoing inflammation or functional disorders imitating irritable bowel syndrome (IBS). Several single-nucleotide polymorphisms (SNPs) have been associated with IBS. However, the impact of IBS genetics on the clinical course of IBD, especially pain levels of patients remains unclear.

METHODS

Data of 857 UC and 1206 CD patients from the Swiss IBD Cohort Study were analysed. We tested the association of the maximum of the abdominal pain item of disease activity indices in UC and CD over the study period with 16 IBS-associated SNPs, using multivariate ANOVA models.

RESULTS

In UC patients, the SNPs rs1042713 (located on the ADRB2 gene) and rs4663866 (close to the HES6 gene) were associated with higher abdominal pain levels (P = 0.044; P = 0.037, respectively). Abdominal pain was not associated with any markers of patient management in a model adjusted for confounders. In CD patients, higher levels of abdominal pain correlated with the number of physician contacts (P < 10^-15), examinations (P < 10^-12), medical therapies (P = 0.023) and weeks of hospitalisation (P = 0.0013) in a multivariate model.

CONCLUSIONS

We detected an association between maximal abdominal pain in UC patients and two IBS-associated SNPs. Abdominal pain levels had a pronounced impact on diagnostic and therapeutic procedures in CD but not in UC patients.

Genetic risk factors predict disease progression in Crohn's disease patients of the Swiss inflammatory bowel disease cohort

BACKGROUND

Crohn's disease (CD) may progress from an inflammatory to a stricturing or penetrating disease phenotype. The aim of our study was to identify single nucleotide polymorphisms (SNPs) that predict disease progression in patients of the Swiss IBD Cohort Study (SIBDCS).

METHODS

We applied a multi-state Markov model for progression behavior of CD with three behavioral states according to the Montreal classification. The model considered transition from B1 to B2/B3 or from B2 to B3 stage. Model dynamics were summarized with transition intensities by including the effect of SNPs and calculating transition intensities for each SNP.

RESULTS

We included 1276 CD patients [669 (52.4%) B1, 248 (19.4%) B2, 359 (28.1%) B3 patients] with a median follow-up of 6.8 (interquartile range = 3.6-9.1; range 0-11.6) years. Probability for a B1 patient to develop a stenosis (B1 to B2, q = 0.033) was twice as much as compared to developing a penetrating complication (B3) during the disease course. In contrast, the probability of entering B3 stage was similar regardless of whether antecedent stricture was present (B2 to B3, q = 0.016) or not (B1 to B3, q = 0.016). We identified SNPs within the gene loci encoding ZMIZ1, LOC105373831 and KSR1 as carrying the highest risk for progression to B3, while the presence of SNPs within gene loci TNFSF15 and CEBPB-PTPN1 protected from progression to B2 or B3.

CONCLUSION

We identified new genetic risk factors that can predict disease course in CD patients. A closer understanding on the functional impact of these genetic variations might improve our treatment options finally to prevent disease progression in CD patients.

Lower Risk of B1-to-pB3-Stage Migration in Crohn's Disease Upon Immunosuppressive and Anti-TNF Treatment in the Swiss IBD Cohort Study

BACKGROUND

While the long-term evolution of disease behavior in Crohn's disease has been well described in the pre-anti-TNF era, our knowledge thereon remains scarce after the introduction of anti-TNF.

AIMS

Our investigation examined the long-term evolution of disease concerning Montreal classification's B-stages over time in patients enrolled into the Swiss IBD Cohort Study between 2006 and 2017.

METHODS

We analyzed prospectively collected SIBDCS data using a Markov model and multivariate testing for effects of treatment and other confounders on B-stage migration over time. The primary outcome was a transition in disease behavior from B1 to either B2 or pB3, or from B2 to pB3, respectively.

RESULTS

The 10- and 15-year probability of remaining in B1 was 0.61 and 0.48, as opposed to a probability to migrate to B2 or B3 of 0.25 or 0.14, and 0.32 or 0.2, after 10 and 15 years, respectively. In multivariate testing, the hazard ratio for migrating from B1 to pB3 (HR 0.27) and from B2 to pB3 (HR 0.12) was lower in patients > 40 years compared to patients < 17 years. We found that immunosuppression (HR 0.38) and treatment with anti-TNF for > 1 year (HR 0.30) were associated with a decreased likelihood of transitioning from stage B1 to pB3.

CONCLUSIONS

While in the anti-TNF era most patients with Crohn's disease will eventually develop stricturing and/or penetrating complications, our data indicate that immunosuppressive and anti-TNF treatment for more than 1 year reduce the risk of transitioning from stage B1 to pB3 in the long-term run.

Review article: impact of cigarette smoking on intestinal inflammation-direct and indirect mechanisms

BACKGROUND

The inflammatory bowel diseases, Crohn's disease and ulcerative colitis are related multifactorial diseases. Their pathogenesis is influenced by each individual's immune system, the environmental factors within exposome and genetic predisposition. Smoking habit is the single best-established environmental factor that influences disease phenotype, behaviour and response to therapy.

AIM

To assess current epidemiological, experimental and clinical evidence that may explain how smoking impacts on the pathogenesis of inflammatory bowel disease.

METHODS

A Medline search for 'cigarette smoking', in combination with terms including 'passive', 'second-hand', 'intestinal inflammation', 'Crohn's disease', 'ulcerative colitis', 'colitis'; 'intestinal epithelium', 'immune system', 'intestinal microbiota', 'tight junctions', 'mucus', 'goblet cells', 'Paneth cells', 'autophagy'; 'epigenetics', 'genes', 'DNA methylation', 'histones', 'short noncoding/long noncoding RNAs'; 'carbon monoxide/CO' and 'nitric oxide/NO' was performed.

RESULTS

Studies found evidence of direct and indirect effects of smoking on various parameters, including oxidative damage, impairment of intestinal barrier and immune cell function, epigenetic and microbiota composition changes, that contribute to the pathogenesis of inflammatory bowel disease.

CONCLUSIONS

Cigarette smoking promotes intestinal inflammation by affecting the function and interactions among intestinal epithelium, immune system and microbiota/microbiome.

Should We Divide Crohn's Disease Into Ileum-Dominant and Isolated Colonic Diseases?

Crohn's disease (CD) is an inflammatory bowel disease that can involve any region of the gastrointestinal tract. First described in 1932 as terminal ileitis or regional enteritis, it predominately involves the ileum with or without colonic involvement. Isolated colonic CD was first described in 1960 and since then the phenotypic classification of CD has evolved to stratify patients into isolated ileal, ileocolonic, or isolated colonic involvement. In the current review we evaluate the published literature regarding differences in epidemiology, natural history, pathogenesis, response to therapy, and disease monitoring, when stratified by disease location. Based on the available evidence consideration could be given to a new classification for CD, which splits it into ileum dominant (isolated ileal and ileocolonic) and isolated colonic disease. This may allow for a more optimized approach to clinical care and scientific research for CD.

[From Axial Spondyloarthritis to Osteoporosis - Spectrum of Skeletal Involvement in Inflammatory Bowel Diseases]

From Axial Spondyloarthritis to Osteoporosis - Spectrum of Skeletal Involvement in Inflammatory Bowel Diseases Abstract. Inflammatory bowel diseases (IBD) are frequently accompanied by non-inflammatory joint pain and inflammatory spondyloarthritides. Spondyloarthritides can restrict joint function and typically manifest with inflammatory back pain with nightly pain and morning stiffness that improves upon exercising. In other patients, small or large peripheral joints are predominantly involved. Treatment comprises pain medication including COX-II selective non-steroidal anti-inflammatory drugs (NSAID), since non-selective NSAID can aggravate IBD. For axial manifestations, physiotherapy and tumor necrosis factor (TNF) inhibitors are effective, while for peripheral manifestations steroid injections, sulfasalazine and TNF inhibitors are useful. Osteopenia and osteoporosis may result from inflammation, malabsorption and/or steroids. Long-lasting disease activity or steroid treatment should prompt osteoporosis screening. Adequate calcium and vitamin D intake must be ensured and treatment with bisphosphonates evaluated.

The Effect of Early-Life Environmental Exposures on Disease Phenotype and Clinical Course of Crohn's Disease in Children

OBJECTIVES

Environmental factors play an important role in the pathogenesis of Crohn's Disease (CD). In particular, by virtue of the instability of the microbiome and development of immunologic tolerance, early life factors may exert the strongest influence on disease risk and phenotype.

METHODS

We used data from 1119 CD subjects recruited from RISK inception cohort to examine the impact of early life environment on disease progression. Our primary exposures of interest were breastfeeding in infancy and exposure to maternal, active, or passive smoke. Our primary outcomes were development of complicated (stricturing or penetrating) disease, and need for CD-related hospitalization, and surgery. Multivariable logistic regression models were used to define independent associations, adjusting for relevant covariates.

RESULTS

Our study cohort included 1119 patients with CD among whom 15% had stricturing (B2) or penetrating disease (B3) by 3 years. 331 patients (35%) and 95 patients (10.6%) required CD-related hospitalizations and surgery respectively. 74.5% were breastfed in infancy and 31% were exposed to smoking among whom 7% were exposed to maternal smoke. On multivariable analysis, a history of breastfeeding was inversely associated with complicated (B2/B3 disease) 0.65, CI 95% 0.44-96; P = 0.03) in pediatric CD. Maternal smoking during pregnancy was associated with increased risk of hospitalization during the 3-year follow-up period (OR 1.75, CI 95% 1.05-2.89; P = 0.03).

CONCLUSIONS

Early life environmental factors influence the eventual phenotypes and disease course in CD.

Editorial: the influence of genetic factors in mediating the effects of tobacco smoke in IBD-Authors' reply

Linked Content

This article is linked to Adams et al and Lang et al papers. To view these articles visit https://doi.org/10.1111/apt.14334 and https://doi.org/10.1111/apt.14378.

Editorial: the influence of genetic factors in mediating the effects of tobacco smoke in IBD

Linked Content

This article is linked to Lang et al papers. To view these articles visit https://doi.org/10.1111/apt.14378 and https://doi.org/10.1111/apt.14447.