The role of smoking in Crohn's disease as defined by clinical variables

Genetic and environmental factors influencing Crohn's disease

This editorial discusses Pellegrino and Gravina's essay. Crohn's disease (CD) is a complex and multifactorial disease that is influenced by a combination of genetic and environmental factors. While genetic factors play a key role in the development of the disease, environmental factors also play a significant role in influencing the risk of developing CD. By looking at present understanding of CD pathogenesis, we emphasize the important factors involved in the development of this illness, such as nucleotide-binding oligomerization domain-2, smoking, and vitamin D. Understanding the interplay between genetic and environmental factors is crucial for developing effective strategies for preventing and treating this chronic inflammatory bowel disease.

Effects of smoking on clinical treatment outcomes amongst patients with chronic inflammatory diseases initiating biologics: secondary analyses of the prospective BELIEVE cohort study

The prevalence and disease burden of chronic inflammatory diseases (CIDs) are predicted to rise. Patients are commonly treated with biological agents, but the individual treatment responses vary, warranting further research into optimizing treatment strategies. This study aimed to compare the clinical treatment responses in patients with CIDs initiating biologic therapy based on smoking status, a notorious risk factor in CIDs. In this multicentre cohort study including 233 patients with a diagnosis of Crohn's disease, ulcerative colitis, rheumatoid arthritis, axial spondyloarthritis, psoriatic arthritis or psoriasis initiating biologic therapy, we compared treatment response rates after 14 to 16 weeks and secondary outcomes between smokers and non-smokers. We evaluated the contrast between groups using logistic regression models: (i) a "crude" model, only adjusted for the CID type, and (ii) an adjusted model (including sex and age). Among the 205 patients eligible for this study, 53 (26%) were smokers. The treatment response rate among smokers (n = 23 [43%]) was lower compared to the non-smoking CID population (n = 92 [61%]), corresponding to a "crude" OR of 0.51 (95% CI: [0.26;1.01]) while adjusting for sex and age resulted in consistent findings: 0.51 [0.26;1.02]. The contrast was apparently most prominent among the 38 RA patients, with significantly lower treatment response rates for smokers in both the "crude" and adjusted models (adjusted OR 0.13, [0.02;0.81]). Despite a significant risk of residual confounding, patients with CIDs (rheumatoid arthritis in particular) should be informed that smoking probably lowers the odds of responding sufficiently to biological therapy. Registration: Clinical.Trials.gov NCT03173144.

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.

Factors associated with surgical resection in patients with Crohn's disease: long-term evaluation

PURPOSE

To evaluate patient characteristics and factors associated with surgical resection in patients with Crohn's disease (CD).

METHODS

An analysis was performed on data from 295 patients with CD in follow-up from 2001 to 2018. Medical record data comprised age, gender, location, behavior and duration of the CD, smoking, and extraintestinal manifestation. Patients were divided into two groups according to the presence or absence of surgical resection.

RESULTS

Out of the 295 patients with CD, 155 underwent surgical resection (53.2% male, mean age: 43.88 ± 14.35 years). The main indications for surgery were stenosis (44.5%), clinical intractability (15.5%), and intra-abdominal fistulas (15.5%). Smoking (p < 0.001), longer CD duration (p < 0.0001), ileo-colonic location (p = 0.003), stenosing behavior (p < 0.0001), and fistulizing behavior (p < 0.0001) were significantly associated with surgical resection. Initial use of biological was significantly more frequent in the group of patients without surgical resection (p < 0.001).

CONCLUSIONS

Patients with CD still frequently need surgical treatment. Smoking (current or past), longer disease time, stenosing and fistulizing behavior, and ileo-colonic localization in CD patients were associated with a higher risk of surgery. Awareness about factors associated with unfavorable outcome allows such patients to be treated more appropriately.

Current Approach to Risk Factors and Biomarkers of Intestinal Fibrosis in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), especially Crohn's disease (CD), characterized by a chronic inflammatory process and progressive intestinal tissue damage, leads to the unrestrained proliferation of mesenchymal cells and the development of bowel strictures. Complications induced by fibrosis are related to high rates of morbidity and mortality and lead to a substantial number of hospitalizations and surgical procedures, generating high healthcare costs. The development of easily obtained, reliable fibrogenesis biomarkers is essential to provide an important complementary tool to existing diagnostic and prognostic methods in IBD management, guiding decisions on the intensification of pharmacotherapy, proceeding to surgical methods of treatment and monitoring the efficacy of anti-fibrotic therapy in the future. The most promising potential markers of fibrosis include cartilage oligomeric matrix protein (COMP), hepatocyte growth factor activator (HGFA), and fibronectin isoform- extra domain A (ED-A), as well as antibodies against granulocyte macrophage colony-stimulating factor (GM-CSF Ab), cathelicidin (LL-37), or circulatory miRNAs: miR-19a-3p and miR-19b-3p. This review summarizes the role of genetic predisposition, and risk factors and serological markers potentially contributing to the pathophysiology of fibrotic strictures in the course of IBD.

Comprehensive review and update of stricturing Crohn's disease

Up to 50% of patients with Crohn's disease develop a stricture within 10 years of diagnosis. Crohn's strictures can compose of inflammation, fibrosis or smooth muscle expansion and usually a combination of these. There have been numerous new developments in imaging modalities in determining the composition of Crohn's strictures. Magnetic resonance imaging remains the best upfront imaging modality to characterize Crohn's strictures. Gastrointestinal ultrasound (GIUS) has an increasing role in clinical practice, particularly for monitoring stricture response as a treat-to-target tool. Novel imaging techniques to differentiate between fibrosis and inflammatory strictures have been developed including contrast-enhanced GIUS, strain or shear wave elastography with GIUS and multiple new magnetic resonance imaging (MRI) protocols, including diffusion weighted, delayed contrast enhancement and magnetization transfer MR protocols. However, these techniques require further validation and standardization. Regarding therapeutics, anti-tumor necrosis agents with a treat-to-target strategy have the highest quality evidence in treating strictures and can lead to stricture regression in some cases. Endoscopic balloon dilatation remains a mainstay in the treatment algorithm of treating predominantly fibrostenotic Crohn's strictures, particularly those which are symptomatic, < 5 cm in length and not causing prestenotic dilatation. Endoscopic balloon dilatation has greater effectiveness in anastomotic strictures. Surgery remains an important treatment option in Crohn's strictures, with segmental resection and stricturoplasty having their own advantages and disadvantages. Kono-S anastomosis may be superior to conventional anastomosis for endoscopic recurrence; however, further high-quality studies are required to confirm this. Using risk stratification models such as the BACARDI risk model is important to guide management decisions between a medical and surgical approach. Early post-operative medical prophylaxis with an advanced therapy is an important consideration to prevent disease recurrence. This review expands on the above topics, highlights research gaps and provides a suggested investigation and management pathway in stricturing Crohn's disease.

Fibrotic Strictures in Crohn's Disease: Mechanisms and Predictive Factors

Fibrotic strictures are one of the most severe complications of Crohn's Disease (CD). They occur in about 50% of patients at five years and in 70% at ten years of the diagnosis. The only treatment available for symptomatic fibrotic strictures is surgical resection and endoscopic dilation. Both strategies are associated with a high rate of recurrence, and with multiple surgical resections, which pose the threat of surgical morbidity and short bowel syndrome. Therefore, it is crucial to identify, early, the patients more prone to develop intestinal fibrosis to intensify follow-ups, switch to more aggressive treatments, and suggest lifestyle modifications. Scarce data are available concerning biomarkers and genetic determinants to predict which patient will develop intestinal fibrosis. Biologic or clinical markers would be useful to determine this subgroup of CD patients and to predict the onset of intestinal fibrosis and, ideally, its severity. Furthermore, the identification of environmental risk factors may suggest lifestyle changes aimed at modifying the natural course, thus decreasing the risk of complicated CD. In this review, we will critically revise clinical, environmental, genetic, and serologic factors that have been associated with a complicated CD course with a particular focus on the fibrostenosing phenotype and their possible implications as predictive factors of intestinal fibrosis.

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.

Best practices on immunomodulators and biologic agents for ulcerative colitis and Crohn's disease in Asia

The Asia-Pacific Working Group on Inflammatory Bowel Disease was established in Cebu, Philippines, under the auspices of the Asia-Pacific Association of Gastroenterology with the goal of improving inflammatory bowel disease care in Asia. This consensus is carried out in collaboration with Asian Organization for Crohn's and Colitis. With biologic agents and biosimilars becoming more established, it is necessary to conduct a review on existing literature and establish a consensus on when and how to introduce biologic agents and biosimilars in conjunction with conventional treatments for ulcerative colitis and Crohn's disease in Asia. These statements also address how pharmacogenetics influences the treatments of ulcerative colitis and Crohn's disease and provides guidance on response monitoring and strategies to restore loss of response. Finally, the review includes statements on how to manage treatment alongside possible hepatitis B and tuberculosis infections, both common in Asia. These statements have been prepared and voted upon by members of inflammatory bowel disease workgroup employing the modified Delphi process. These statements do not intend to be all-encompassing, and future revisions are likely as new data continue to emerge.

Best practices on immunomodulators and biologic agents for ulcerative colitis and Crohn's disease in Asia

The Asia-Pacific Working Group on inflammatory bowel disease (IBD) was established in Cebu, Philippines, under the auspices of the Asian Pacific Association of Gastroenterology with the goal of improving IBD care in Asia. This consensus is carried out in collaboration with Asian Organization for Crohn's and Colitis. With biologic agents and biosimilars becoming more established, it is necessary to conduct a review on existing literature and establish a consensus on when and how to introduce biologic agents and biosimilars in the conjunction with conventional treatments for ulcerative colitis (UC) and Crohn's disease (CD) in Asia. These statements also address how pharmacogenetics influence the treatments of UC and CD and provide guidance on response monitoring and strategies to restore loss of response. Finally, the review includes statements on how to manage treatment alongside possible hepatitis B and tuberculosis infections, both common in Asia. These statements have been prepared and voted upon by members of IBD workgroup employing the modified Delphi process. These statements do not intend to be all-encompassing and future revisions are likely as new data continue to emerge.

Smoking and Inflammatory Bowel Disease: A Comparison of China, India, and the USA

BACKGROUND

Cigarette smoking is thought to increase the risk of Crohn's disease (CD) and exacerbate the disease course, with opposite roles in ulcerative colitis (UC). However, these findings are from Western populations, and the association between smoking and inflammatory bowel disease (IBD) has not been well studied in Asia.

AIMS

We aimed to compare the prevalence of smoking at diagnosis between IBD cases and controls recruited in China, India, and the USA, and to investigate the impact of smoking on disease outcomes.

METHODS

We recruited IBD cases and controls between 2014 and 2018. All participants completed a questionnaire about demographic characteristics, environmental risk factors and IBD history.

RESULTS

We recruited 337 participants from China, 194 from India, and 645 from the USA. In China, CD cases were less likely than controls to be current smokers (adjusted odds ratio [95% CI] 0.4 [0.2-0.9]). There was no association between current or former smoking and CD in the USA. In China and the USA, UC cases were more likely to be former smokers than controls (China 14.6 [3.3-64.8]; USA 1.8 [1.0-3.3]). In India, both CD and UC had similar current smoking status to controls at diagnosis. Current smoking at diagnosis was significantly associated with greater use of immunosuppressants (4.4 [1.1-18.1]) in CD cases in China.

CONCLUSIONS

We found heterogeneity in the associations of smoking and IBD risk and outcomes between China, India, and the USA. Further study with more adequate sample size and more uniform definition of smoking status is warranted.

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.

Health Maintenance in Inflammatory Bowel Disease

PURPOSE OF REVIEW

Patients with inflammatory bowel disease (IBD) are not receiving preventative care services at the same rate as the general population. IBD patients are at increased risk for infections, osteoporosis, and certain malignancies secondary to their disease and as they are on immunosuppressive therapy. They are a younger population and often times consider their gastroenterologist as their primary care physician. In this review, we discuss up-to-date evidence pertaining to vaccine-preventable illnesses in the immunosuppressed IBD patient, screening for bone health, cervical cancer, skin malignancies, psychological wellbeing, and smoking cessation.

RECENT FINDINGS

Vaccinations are recommended in the IBD population as they are immunosuppressed and at increased risk for acquiring influenza and pneumonia. Not only are they at greater risk to acquire it but they also have a much severe complicated course. Ideally, IBD patients should be vaccinated prior to initiating immunosuppression and most inactive vaccines can be administered to them while they are on therapy. All IBD patients should be encouraged to stop smoking and have adequate vitamin D intake along with appropriate applicable cancer screenings. Gastroenterologists must work in collaboration with primary care providers along with other specialists to help provide our patients well-rounded care for their IBD.

Preoperative optimization of patients with inflammatory bowel disease undergoing gastrointestinal surgery: a systematic review

PURPOSE

Surgical management of inflammatory bowel disease (IBD) is a challenging task. The aim of preoperative optimization (PO) is to decrease the risk of complications and reduce the length of postoperative stay. The aim of this study was to review and grade the available evidence, attain clear recommendations, and point out potential future research.

METHODS

Studies were identified from electronic databases (PubMed, Embase, and Cochrane Library) and scanning reference lists in relevant papers. English-written studies examining PO in adult patients with IBD were included. Eight PO factors were investigated.

RESULTS

Management of IBD is a multidisciplinary task. Steroid withdrawal is recommended while steroid stress dose is not recommended. Thiopurines appear to be safe, but it may be prudent to plan the procedure remotely from the last dose of an anti-TNF agent. Nutritional risk screening is recommended to unveil and correct any malnutrition. Thrombosis prophylaxis prior to surgery is well supported by evidence while extended 4-week prophylaxis needs further research. Percutaneous ultrasound or CT-guided drainage for intra-abdominal abscesses is recommended, but it is unclear for how long supplementary antibiotics (ABs) should be used. Oral AB 24 h prior to open surgery might improve outcome if given as complementary to IV perioperative AB. Mechanical bowel preparation is not supported by evidence. Comorbidities must be treated accordingly prior to surgical intervention. Smoking cessation can be beneficial for wound healing.

CONCLUSION

Multimodel PO intervention in IBD patients is recommended.

Smoking is Associated with Higher Disease-related Costs and Lower Health-related Quality of Life in Inflammatory Bowel Disease

BACKGROUND AND AIMS

Smoking affects the course of inflammatory bowel disease [IBD]. We aimed to study the impact of smoking on IBD-specific costs and health-related quality-of-life [HrQoL] among adults with Crohn's disease [CD] and ulcerative colitis [UC].

METHODS

A large cohort of IBD patients was prospectively followed during 1 year using 3-monthly questionnaires on smoking status, health resources, disease activity and HrQoL. Costs were calculated by multiplying used resources with corresponding unit prices. Healthcare costs, patient costs, productivity losses, disease course items and HrQoL were compared between smokers, never-smokers and ex-smokers, adjusted for potential confounders.

RESULTS

In total, 3030 patients [1558 CD, 1054 UC, 418 IBD-unknown] were enrolled; 16% smoked at baseline. In CD, disease course was more severe among smokers. Smoking was associated with > 30% higher annual societal costs in IBD (€7,905 [95% confidence interval €6,234 - €9,864] vs €6,017 [€5,186 - €6,946] in never-smokers and €5,710 [€4,687 - €6,878] in ex-smokers, p = 0.06 and p = 0.04, respectively). In CD, smoking patients generated the highest societal costs, primarily driven by the use of anti-tumour necrosis factor compounds. In UC, societal costs of smoking patients were comparable to those of non-smokers. Societal costs of IBD patients who quitted smoking > 5 years before inclusion were lower than in patients who quitted within the past 5 years (€ 5,135 [95% CI €4,122 - €6,303] vs €9,342 [€6,010 - €12,788], p = 0.01). In both CD and UC, smoking was associated with a lower HrQoL.

CONCLUSIONS

Smoking is associated with higher societal costs and lower HrQoL in IBD patients. Smoking cessation may result in considerably lower societal costs.

Smoking influences the need for surgery in patients with the inflammatory bowel diseases: a systematic review and meta-analysis incorporating disease duration

Background

Studies examining the association between smoking and the need for surgery in patients with Crohn’s disease and ulcerative colitis have reached inconsistent conclusions. These studies often do not differentiate between patients undergoing early surgery and patients having surgery later in their disease course. Our study examined the association between smoking status and time to first bowel resection in patients with Crohn’s disease and ulcerative colitis.

Methods

We searched MEDLINE and EMBASE for studies (n = 12) reporting on the association between smoking status (current, former, and never) and surgery in IBD, and incorporated disease duration in the analysis. Hazard ratios (HR) with 95% confidence intervals (CI) were pooled across studies using random effects models.

Results

Current smokers with Crohn’s disease were at increased risk of intestinal resection compared to never smokers (HR 1.27, 95% CI 1.08 to 1.49); however, there was no difference in the need for surgery when comparing former and never smokers (HR 1.11, 95% CI 0.95 to 1.30). In patients with ulcerative colitis, there was no difference in the need for colectomy when comparing current smokers to never smokers (HR 0.98, 95% CI 0.67 to 1.44). Former smokers with ulcerative colitis were at increased risk of colectomy (HR 1.38, 95% CI 1.04 to 1.83) compared to never smokers.

Conclusions

Current smokers with Crohn’s disease are at increased risk of surgery, while former smokers with ulcerative colitis have increased risk of colectomy.

Electronic supplementary material

The online version of this article (doi:10.1186/s12876-016-0555-8) contains supplementary material, which is available to authorized users.

Evolution of disease phenotype in pediatric-onset Crohn's disease after more than 10 years follow up-Cohort study

BACKGROUND

Pediatric-onset Crohn's disease (CD) is a heterogeneous disorder which is subjected to progression and complications in a substantial proportion of patients.

AIMS

We aimed to assess the progression in pediatric-onset CD phenotype on long term follow up.

METHODS

Medical charts of pediatric onset CD patients with at least 10 years follow-up were analyzed retrospectively. Disease phenotype was determined at diagnosis and during follow up at different time points. Phenotype was determined according to the Paris classification. The impact of possible predictors on phenotype progression was assessed as well as the association between different therapeutic regimens during disease course and phenotype progression.

RESULTS

Progression of disease location, behavior, and perianal involvement was observed in 20%, 38% and 20% of patients, respectively, after a median follow-up of 16.4 (±4.4) years. Microscopic ileocolonic disease at diagnosis was significant predictors for progression of disease extent. Treatment with anti tumor necrosis factor-ɑ agents and number of flares per years of follow-up were associated with progression of disease extent, behavior and perianal involvement.

CONCLUSION

Disease extent, behavior and prevalence of perianal disease change significantly over time in pediatric-onset CD. In our cohort, most clinical, laboratory and endoscopic parameters do not serve as predictors for long-term disease progression.

Hospitalizations for Acute Myocardial Infarction Are Decreased Among Patients with Inflammatory Bowel Disease Using a Nationwide Inpatient Database

BACKGROUND

Questions remain regarding the true prevalence of cardiovascular events such as myocardial infarction (MI) among patients with inflammatory bowel disease (IBD). Using the Nationwide Inpatient Sample (NIS), we aimed to compare the proportion of hospitalizations for acute MI among patients with IBD with that of the general population.

METHODS

This study used data from years 2000 to 2011 in Nationwide Inpatient Sample, the largest publicly available all-payer inpatient database in the United States. International Classification of Diseases, Ninth Revision, Clinical Modification discharge codes were used to identify adult patients with discharge diagnoses of IBD (ulcerative colitis or Crohn's disease), acute MI, and multiple comorbid risk factors for cardiovascular disease. The independent effect of a diagnosis of IBD on risk of acute MI was examined using a multivariable logistic regression model controlling for multiple confounders. Data were analyzed using SAS survey procedures and weighted to reflect national estimates.

RESULTS

We identified 567,438 hospitalizations among patients with IBD and 78,121,000 hospitalizations among the general population. Patients with IBD were less likely to be hospitalized for acute MI than patients in the general population (1.3% versus 3.1%, P < 0.001). In adjusted analyses, the odds of hospitalization for acute MI among patients with IBD were decreased when compared with the general population (odds ratio, 0.51; 95% confidence interval, 0.50-0.52).

CONCLUSIONS

Despite prior reports of a potentially increased risk of acute MI among patients with IBD, in a nationwide inpatient database, lower rates of acute MI were demonstrated in the IBD population when compared with the general population.

Patients With Inflammatory Bowel Disease Are Unaware of the Impact of Smoking on Their Disease

BACKGOUND

Tobacco is one of the most significant risk factors for inflammatory bowel disease (IBD).

GOALS

The main objective was to assess the knowledge of patients with IBD regarding the effects of tobacco on their disease. Secondary objectives were to determine the source of their knowledge, the influence of their knowledge on their intent to quit smoking, and the association between patients' characteristics and their knowledge.

STUDY

Patients with IBD completed a self-administered questionnaire on demographic data, severity of disease, and effects of tobacco on their disease.

RESULTS

In total 259 patients [182 with Crohn's disease, 77 with ulcerative colitis (UC)] participated. The prevalence of current smokers, exsmokers, and nonsmokers was 19.6%, 40.2%, and 40.2%, respectively. Patients with Crohn's disease were more aware of the effects of tobacco on their disease compared with those with UC (57.7% vs. 13.0%, P<0.0001). In informed patients, the main source of information was the gastroenterologist (56.9%). The intent to quit smoking was superior in informed patients compared with those uninformed (78.6% vs. 47.8%, P=0.046). Older patients (odds ratio=0.97, P=0.01) and patients with UC (odds ratio=0.11, P<0.0001) were less likely to be informed.

CONCLUSIONS

Only half of patients with IBD are aware of the risks of smoking associated with their disease, whereas their intent to quit smoking is directly related to their awareness. In the scope of IBD's treatment, management of smoking cessation should be undertaken in all smokers.

Smoking is Associated With Extra-intestinal Manifestations in Inflammatory Bowel Disease

BACKGROUND AND AIMS

Smoking affects the course of disease in patients with ulcerative colitis (UC) and Crohn's disease (CD). We aimed to study the association between smoking and extra-intestinal manifestations (EIMs) in inflammatory bowel disease (IBD).

METHODS

We cross-sectionally explored the association between smoking and EIMs in IBD in three cohort studies: (1) the COIN study, designed to estimate healthcare expenditures in IBD; (2) the Groningen study, focused on cigarette smoke exposure and disease behaviour in IBD; and (3) the JOINT study, evaluating joint and back manifestations in IBD.

RESULTS

In the COIN, Groningen and JOINT cohorts, 3030, 797 and 225 patients were enrolled, of whom 16, 24 and 23.5% were current smokers, respectively. Chronic skin disorders and joint manifestations were more prevalent in smoking IBD patients than in non-smokers (COIN, 39.1 vs 29.8%, p <0.01; Groningen, 41.7 vs 30.0%, p <0.01) in both CD and UC. In the JOINT cohort, smoking was more prevalent in IBD patients with joint manifestations than in those without (30.3 vs 13.0%, p <0.01). EIMs appeared to be more prevalent in high- than in low-exposure smokers (56.0 vs 37.1%, p = 0.10). After smoking cessation, the prevalence of EIMs in IBD patients rapidly decreased towards levels found in never smokers (lag time: COIN cohort, 1-2 years; Groningen cohort, within 1 year).

CONCLUSIONS

There is a robust dose-dependent association between active smoking and EIMs in both CD and UC patients. Smoking cessation was found to result in a rapid reduction of EIM prevalence to levels encountered in never smokers.

Impact of Smoking Cessation on the Clinical Course of Crohn's Disease Under Current Therapeutic Algorithms: A Multicenter Prospective Study

OBJECTIVES

Given the importance of tobacco smoking (TS) as the only environmental factor repeatedly linked to the development of the Crohn's disease (CD), it is surprising that very few prospective studies have assessed whether TS is associated with an increased frequency of clinical relapse. Our aim was to evaluate the current impact of TS on disease relapse and the clinical benefit of quitting smoking in the present era of widespread use of anti-TNF drugs and immunosuppressants.

METHODS

This was a multicenter prospective cohort study, which included 573 CD patients in clinical remission with various smoking habits. All smokers were advised to quit. Patients not exposed to tobacco before inclusion (non- and former smokers), continuing smokers, and quitters were compared regarding differences in disease outcomes during a follow-up of 4 years.

RESULTS

A total of 148 continuing smokers, 190 nonsmokers, 160 former smokers, and 75 quitters were included. In comparison with nonsmokers, continuing smokers relapsed more frequently with an incidence rate ratio of 1.53 (95% confidence interval (CI): 1.10-2.17). Former smokers and quitters had similar relapse incidences compared with nonsmokers. Smoking was an independent predictor for disease relapse in the multivariate analysis (hazard ratio: 1.58 (95% CI 1.20-2.09). In the time-dependent analysis, continuing smokers had earlier relapse, regardless of anti-TNF or immunosuppressant use.

CONCLUSIONS

Continuing smokers have more disease relapses, and patients who quit smoking have a similar relapse incidence compared with nonsmokers.

Influence of environmental factors in the development of inflammatory bowel diseases

Idiopathic inflammatory bowel diseases (IBD), Crohn's disease (CD) and ulcerative colitis (UC), are multifactorial diseases that are manifested after disruption of a genetic predisposed individual and its intestinal microflora through an environmental stimulus. Urbanization and industrialization are associated with IBD. Epidemiological data, clinical observations and family/immigrants studies indicate the significance of environmental influence in the development of IBD. Some environmental factors have a different effect on the subtypes of IBD. Smoking and appendectomy is negatively associated with UC, but they are aggravating factors for CD. A westernized high fat diet, full of refined carbohydrates is strongly associated with the development of IBD, contrary to a high in fruit, vegetables and polyunsaturated fatty acid-3 diet that is protective against these diseases. High intake of nonsteroidal antiinflammatory drug and oral contraceptive pills as well as the inadequacy of vitamin D leads to an increased risk for IBD and a more malignant course of disease. Moreover, other factors such as air pollution, psychological factors, sleep disturbances and exercise influence the development and the course of IBD. Epigenetic mechanism like DNA methylation, histone modification and altered expression of miRNAS could explain the connection between genes and environmental factors in triggering the development of IBD.

The Neuromodulation of the Intestinal Immune System and Its Relevance in Inflammatory Bowel Disease

One of the main tasks of the immune system is to discriminate and appropriately react to “danger” or “non-danger” signals. This is crucial in the gastrointestinal tract, where the immune system is confronted with a myriad of food antigens and symbiotic microflora that are in constant contact with the mucosa, in addition to any potential pathogens. This large number of antigens and commensal microflora, which are essential for providing vital nutrients, must be tolerated by the intestinal immune system to prevent aberrant inflammation. Hence, the balance between immune activation versus tolerance should be tightly regulated to maintain intestinal homeostasis and to prevent immune activation indiscriminately against all luminal antigens. Loss of this delicate equilibrium can lead to chronic activation of the intestinal immune response resulting in intestinal disorders, such as inflammatory bowel diseases (IBD). In order to maintain homeostasis, the immune system has evolved diverse regulatory strategies including additional non-immunological actors able to control the immune response. Accumulating evidence strongly indicates a bidirectional link between the two systems in which the brain modulates the immune response via the detection of circulating cytokines and via direct afferent input from sensory fibers and from enteric neurons. In the current review, we will highlight the most recent findings regarding the cross-talk between the nervous system and the mucosal immune system and will discuss the potential use of these neuronal circuits and neuromediators as novel therapeutic tools to reestablish immune tolerance and treat intestinal chronic inflammation.

The Influence of Second-Hand Cigarette Smoke Exposure during Childhood and Active Cigarette Smoking on Crohn's Disease Phenotype Defined by the Montreal Classification Scheme in a Western Cape Population, South Africa

Background

Smoking may worsen the disease outcomes in patients with Crohn’s disease (CD), however the effect of exposure to second-hand cigarette smoke during childhood is unclear. In South Africa, no such literature exists. The aim of this study was to investigate whether disease phenotype, at time of diagnosis of CD, was associated with exposure to second-hand cigarette during childhood and active cigarette smoking habits.

Methods

A cross sectional examination of all consecutive CD patients seen during the period September 2011-January 2013 at 2 large inflammatory bowel disease centers in the Western Cape, South Africa was performed. Data were collected via review of patient case notes, interviewer-administered questionnaire and clinical examination by the attending gastroenterologist. Disease phenotype (behavior and location) was evaluated at time of diagnosis, according to the Montreal Classification scheme. In addition, disease behavior was stratified as ‘complicated’ or ‘uncomplicated’, using predefined definitions. Passive cigarette smoke exposure was evaluated during 3 age intervals: 0–5, 6–10, and 11–18 years.

Results

One hundred and ninety four CD patients were identified. Cigarette smoking during the 6 months prior to, or at time of diagnosis was significantly associated with ileo-colonic (L3) disease (RRR = 3.63; 95%CI, 1.32–9.98, p = 0.012) and ileal (L1) disease (RRR = 3.54; 95%CI, 1.06–11.83, p = 0.040) compared with colonic disease. In smokers, childhood passive cigarette smoke exposure during the 0–5 years age interval was significantly associated with ileo-colonic CD location (RRR = 21.3; 95%CI, 1.16–391.55, p = 0.040). No significant association between smoking habits and disease behavior at diagnosis, whether defined by the Montreal scheme, or stratified as ‘complicated’ vs ‘uncomplicated’, was observed.

Conclusion

Smoking habits were associated with ileo-colonic (L3) and ileal (L1) disease at time of diagnosis in a South African cohort.

Extraintestinal manifestations of inflammatory bowel disease and the influence of smoking

AIMS

To define the number/frequency of organ systems affected by extraintestinal manifestations (EIMs), to identify factors affecting the clinical course of inflammatory bowel disease (IBD) and EIM development, and to determine the impact of smoking, disease duration and location on the diagnosis of EIMs in Crohn's disease (CD) and ulcerative colitis (UC).

METHODS

IBD patients were derived from a single university colorectal surgery practice. Smoking data were obtained through a modified Behavioral Risk Factor Surveillance System survey. The frequencies of arthritis/arthralgia, primary sclerosing cholangitis (PSC), ocular and cutaneous EIMs were determined.

RESULTS

Of the 757 patients evaluated (CD 488, UC 269), 50% had ≥1 EIM. Arthritis/arthralgia, cutaneous and ocular EIMs were significantly higher in frequency in CD compared to UC patients. Prolonged disease duration was associated with increased prevalence of arthritis/arthralgia in IBD (p ≤ 0.001) as well as PSC (p = 0.049), ocular (p = 0.030) and cutaneous (p = 0.009) EIMs in CD. Disease location affected the occurrence of EIMs in CD. Smoking appeared to increase the prevalence of ocular EIMs in UC (p = 0.026).

CONCLUSION

Arthritis/arthralgia, cutaneous and ocular EIMs occurred in a significantly higher proportion of CD patients. CD patients with longer disease duration had a significantly higher prevalence of PSC, ocular and cutaneous EIMs. Smoking was found to increase ocular EIMs in UC.

The association between childhood environmental exposures and the subsequent development of Crohn's disease in the Western Cape, South Africa

Background

Environmental factors during childhood are thought to play a role in the aetiolgy of Crohn's Disease (CD). However the association between age at time of exposure and the subsequent development of CD in South Africa is unknown.

Methods

A case control study of all consecutive CD patients seen at 2 large inflammatory bowel disease (IBD) referral centers in the Western Cape, South Africa between September 2011 and January 2013 was performed. Numerous environmental exposures during 3 age intervals; 0–5, 6–10 and 11–18 years were extracted using an investigator administered questionnaire. An agreement analysis was performed to determine the reliability of questionnaire data for all the relevant variables.

Results

This study included 194 CD patients and 213 controls. On multiple logistic regression analysis, a number of childhood environmental exposures during the 3 age interval were significantly associated with the risk of developing CD. During the age interval 6–10 years, never having had consumed unpasteurized milk (OR = 5.84; 95% CI, 2.73–13.53) and never having a donkey, horse, sheep or cow on the property (OR = 2.48; 95% CI, 1.09–5.98) significantly increased the risk of developing future CD. During the age interval 11–18 years, an independent risk-association was identified for; never having consumed unpasteurized milk (OR = 2.60; 95% CI, 1.17–6.10) and second-hand cigarette smoke exposure (OR = 1.93; 95% CI, 1.13–3.35).

Conclusion

This study demonstrates that both limited microbial exposures and exposure to second-hand cigarette smoke during childhood is associated with future development of CD.

Smoking in inflammatory bowel disease: impact on disease course and insights into the aetiology of its effect

The chronic intestinal inflammation that characterises Crohn's disease and ulcerative colitis arises from a complex interplay between host genotype, the immune system, and the intestinal microbiota. In addition, environmental factors such as smoking impact on disease onset and progression. Individuals who smoke are more likely to develop Crohn's disease, and smoking is associated with recurrence after surgery and a poor response to medical therapy. Conversely, smoking appears protective against ulcerative colitis and smokers are less likely to require colectomy. The mechanism by which smoking exerts its impact on disease and the rational for the dichotomous effect in patients with Crohn's disease and ulcerative colitis is not clear. Recent evidence suggests that smoking induces alterations to both the innate and acquired immune system. In addition, smoking is associated with a distinct alteration in the intestinal microbiota both in patients with active Crohn's disease and healthy subjects.

Escherichia coli-host macrophage interactions in the pathogenesis of inflammatory bowel disease

Multiple studies have demonstrated alterations in the intestinal microbial community (termed the microbiome) in Crohn’s disease (CD) and several lines of evidence suggest these changes may have a significant role in disease pathogenesis. In active and quiescent disease, both the faecal and mucosa-associated microbiome are discordant with matched controls with reduced biodiversity, changes in dominant organisms and increased temporal variation described. Mucosa-associated adherent, invasive Escherichia coli (E. coli) (AIEC), pro-inflammatory and resistant to killing by mucosal macrophages, appear to be particularly important. AIEC possess several virulence factors which may confer pathogenic potential in CD. Type-1 pili (FimH) allow adherence to intestinal cells via cell-surface carcinoembryonic antigen-related cell adhesion molecules and possession of long polar fimbrae promotes translocation across the intestinal mucosa via microfold (M)-cells of the follicle-associated epithelium. Resistance to stress genes (htrA, dsbA and hfq) and tolerance of an acidic pH may contribute to survival within the phagolysosomal environment. Here we review the current understanding of the role of mucosa-associated E. coli in Crohn’s pathogenesis, the role of the innate immune system, factors which may contribute to prolonged bacterial survival and therapeutic strategies to target intracellular E. coli.

Is it possible to change phenotype progression in Crohn's disease in the era of immunomodulators? Predictive factors of phenotype progression

OBJECTIVES

Crohn's disease (CD) induces cumulative structural damage, initially characterized by a non-stenosing non-penetrating behavior (B1) with progression over time to a fibro-stenosing (B2) and/or penetrating phenotype (B3). Our aim was to assess the long-term evolution of disease behavior of CD and determine what factors predict phenotype progression.

METHODS

This was a study based on prospectively collected data from a CD database in an inflammatory bowel disease outpatient clinic. B1 corresponds to a non-stenosing non-penetrating disease, B2 to a stenosing behavior, and B3 to a penetrating one.

RESULTS

Seven hundred and thirty-six patients with CD (368 female) were followed up for 12.3 years (± 8.4), with 87.0% of them exhibiting B1 phenotype at diagnosis. Of these patients, 28.5% progressed to B2 phenotype and 23.5% to B3. Fifty percent of the patients started azathioprine treatment before phenotype change and 13.9% started anti-tumor necrosis factor-α (anti-TNFα) treatment before phenotype change. Monotherapy with azathioprine before phenotype change as well as combination therapy with azathioprine/anti-TNFα before phenotype change delayed disease progression (B1-B2 or B3) in comparison with patients who did not receive treatment (P<0.001). The hazard ratio (HR) for disease progression was lower for both monotherapy with azathioprine (HR: 0.15, P<0.001) or combination therapy with anti-TNFα (HR: 0.33, P<0.001). Upper gastrointestinal tract involvement, male gender, and steroid use were associated with an early progression of phenotype from B1 to B2 or B3 (P<0.001). The HR for disease progression was higher in patients who used steroids without criteria of dependence or resistance (HR: 2.67, P<0.001) and was even higher in patients with criteria of dependence or resistance (HR: 6.44, P<0.001). Longer delays between CD diagnosis and beginning of therapy with azathioprine and/or anti-TNFα were associated with disease progression. The longer the duration of treatment, the less likely the disease progression.

CONCLUSIONS

Monotherapy with azathioprine before behavior change as well as combination therapy with azathioprine and anti-TNFα before behavior change delays phenotype progression of CD, whereas upper gastrointestinal tract involvement, male gender, and steroid use with or without criteria of steroid dependence are associated with a higher risk for disease progression.

Influence of medical treatment, smoking and disease activity on pregnancy outcomes in Crohn's disease

OBJECTIVE. Little is known about predictors for adverse pregnancy outcomes among women with Crohn's disease (CD). In this population-based study, we examined pregnancy outcomes in CD stratified by medical treatment and smoking status while accounting for disease activity. METHODS. In two Danish regions with a population of 1.6 million, we identified 154 CD women who had given birth within a 6-year period. We combined questionnaire data, prescription data, data from medical records and population-based medical databases. We used logistic regression to estimate prevalence odds ratios (POR) for adverse pregnancy outcomes by different predictors. RESULTS. Among 105 (80%) respondents, 55 (52%) reported taking medication during pregnancy. The majority (95%) were in disease remission. The children's mean birth weight did not differ by maternal medical treatment. As expected, smoking was a predictor of low birth weight. Mean birth weight in children of smokers in medical treatment was significantly reduced by 274 g compared with children of non-smokers who received medical treatment. In children of women without medical treatment, this difference was 126 g between smokers and non-smokers. Women in medical treatment did not have an increased risk of preterm delivery (POR 0.71; 95% confidence interval (CI) 0.18-2.79), congenital malformations (POR 0.60; 0.10-3.76) or cesarean section (POR 1.40; 0.63-3.08). CONCLUSIon. In CD, smoking was negatively associated with child birth weight. This association was most pronounced among women who received medical treatment. Maternal medical treatment for CD did not seem to be a risk factor for adverse pregnancy outcomes.

Smoking does influence disease behaviour and impacts the need for therapy in Crohn's disease in the biologic era

BACKGROUND

Recently, the notion that smoking may adversely affect Crohn's disease (CD) outcomes has been challenged by the suggestion that the widespread use of immunosuppressants and anti-TNF drugs might offset the adverse effects of tobacco.

AIM

To reassess the influence of tobacco smoking on disease phenotype and complications on a time-dependent analysis, taking into account the different therapeutic interventions.

METHODS

We designed a retrospective cohort study of 3224 patients with Crohn's disease. The data were collected from the Spanish national inflammatory bowel disease registry (ENEIDA), including information regarding demographics, clinical characteristics, disease complications, therapeutic interventions and smoking status. Patients were classified as nonsmokers, smokers and former smokers, according to their present and past smoking habits.

RESULTS

In the univariate analysis, smokers had more strictures (22.6% vs. 19.3%, P < 0.05) and less colonic involvement (7.2% vs. 10.9%, P < 0.05), and were more frequently under treatment with steroids (91.6% vs. 85.8%, P < 0.05), immunosuppressants (73.5% vs. 63.6% P < 0.05) or anti-TNF drugs (31.4% vs. 25.1%, P < 0.05) than nonsmokers. In the time-dependent multivariate analysis, smokers were found to have a significantly decreased survival free of stricturing disease (HR: 1.5, CI 95% 1.18-1.90) or perianal complications (HR: 1.50, CI 95% 1.01-1.46), and had a higher risk for requiring thiopurine therapy (HR: 1.20, CI 95% 1.05-1.30).

CONCLUSION

These results suggest that, despite the widespread use of immunosuppressants and anti-TNF drugs, smokers with Crohn's disease still have a more severe disease course, with increased therapeutic requirements when compared with nonsmokers.

Is current smoking still an important environmental factor in inflammatory bowel diseases? Results from a population-based incident cohort

BACKGROUND

Previous studies suggest that smoking is an important environmental factor in inflammatory bowel diseases (IBDs), with dichotomous effects in ulcerative colitis (UC) and Crohn's disease (CD). The aim of this study was to analyze the relationship between smoking and IBD risk in a population-based database from Veszprem Province, which included incident cases diagnosed between January 1, 1977, and December 31, 2008.

METHODS

Data from 1420 incident patients were analyzed (UC: 914, age at diagnosis: 38.9 years; CD: 506, age at diagnosis: 31.5 years). Both inpatient and outpatient records were collected and comprehensively reviewed. Overall, smoking frequency in the adult general population was 36.1%.

RESULTS

Of patients with CD, 47.2% were current smokers at diagnosis. Smoking was more frequent in male patients (P = 0.002) and was associated with an increased risk of CD (odds ratio, 1.96; 95% confidence interval, 1.63-2.37; P < 0.001). In contrast, current smoking was protective against UC (odds ratio, 0.33; 95% confidence interval, 0.27-0.41). The effect of smoking was linked to gender (in CD, more deleterious in male patients) and age at diagnosis and was most prominent in young adults, with a difference already being seen in 18- to 19-year-olds. In CD, a change in disease behavior (P = 0.02), location from ileal or colonic to ileocolonic (P = 0.003), arthritis/arthropathy (P = 0.002), need for steroids (P = 0.06), or AZA (P = 0.038) was more common in current smokers. Smoking in UC was associated with more extensive disease (P = 0.01) and a tendency for decreased need for colectomy (P = 0.06).

CONCLUSIONS

Current smoking was associated with the risk of IBD. This effect was linked to gender and age at diagnosis and was most prominent in young adults. No association was observed in pediatric or elderly patients. The deleterious and protective effects of smoking on the course in CD and UC were partially confirmed.

High smoking cessation rate in Crohn's disease patients after physician advice--the TABACROHN Study

INTRODUCTION

Tobacco smoking has a significant impact on the development of Crohn's disease (CD) and its clinical course, making smoking cessation one of the main goals in CD therapeutic strategy.

AIMS

To evaluate the effectiveness of an advice-based smoking cessation strategy among CD patients.

METHODS

We have performed a prospective multicenter study which enrolled 408 CD smokers. At inclusion all patients were instructed about the risks of smoking and subsequently followed every 3 months. Each center used additional smoking cessation strategies based on available resources. Urinary cotinine and exhaled carbon monoxide levels were evaluated in a subgroup of patients.

RESULTS

Median study follow up was 18 months. 31% of the patients achieved complete smoking cessation and 23% were smoking-free at the end of their follow up with 8% of smoking relapse. Most patients not achieving smoking cessation did not change their smoking habit with only 5% presenting a decrease in tobacco load. 63% of patients willing to quit smoking received help from another specialist, most frequently the pulmonologist (47%). Surprisingly, most patients (88%) tried to quit smoking with no pharmacological therapy and bupropion, varenicline and nicotine replacement treatment were used in few patients. Urinary cotinine and exhaled CO levels tested in a subgroup of patients proved to have a good correlation with the self-reported smoking habit. No predictors of successful smoking cessation were identified.

CONCLUSION

Our results underline that an anti-tobacco strategy mostly based on CD patients's education and counseling is feasible and effective in helping patients reach complete abstinence.

Clinical factors predictive of Crohn's disease complications and surgery

Crohn's disease (CD) is a progressive disease that is subdivided into three phenotypes: inflammatory, stricturing and penetrating. At diagnosis, most CD patients have inflammatory disease. However, the natural history of CD is one of progression over time to structural complications of the gastrointestinal tract (strictures and fistulae) requiring hospitalizations and surgeries. There is now evidence that early treatment with immunosuppressants and biologics can halt the development of inflammatory damage/fibrosis because of their potential to induce complete mucosal healing. This change in the natural course of CD, mediated by mucosal healing, is associated with a reduction in the incidence of serious complications (those requiring hospitalization and surgeries). Nevertheless, the clinical course of CD varies considerably from one patient to another, and the exact point at which immunosuppressants and/or biologics should be used has not yet been established. Given the difficulty in predicting which individuals will progress to complications and the fact that these therapeutic agents are associated with certain risks (lymphomas and opportunistic infections), efforts are underway to identify the risk factors that will facilitate the classification of patients into high-risk and low-risk groups at the time of diagnosis and to tailor therapy accordingly. This paper is a review of the currently available evidence on the clinical risk factors predictive of CD complications and surgery.

Evolution of disease phenotype in adult and pediatric onset Crohn's disease in a population-based cohort

AIM

To investigate the evolution of disease phenotype in adult and pediatric onset Crohn's disease (CD) populations, diagnosed between 1977 and 2008.

METHODS

Data of 506 incident CD patients were analyzed (age at diagnosis: 28.5 years, interquartile range: 22-38 years). Both in- and outpatient records were collected prospectively with a complete clinical follow-up and comprehensively reviewed in the population-based Veszprem province database, which included incident patients diagnosed between January 1, 1977 and December 31, 2008 in adult and pediatric onset CD populations. Disease phenotype according to the Montreal classification and long-term disease course was analysed according to the age at onset in time-dependent univariate and multivariate analysis.

RESULTS

Among this population-based cohort, seventy-four (12.8%) pediatric-onset CD patients were identified (diagnosed ≤ 17 years of age). There was no significant difference in the distribution of disease behavior between pediatric (B1: 62%, B2: 15%, B3: 23%) and adult-onset CD patients (B1: 56%, B2: 21%, B3: 23%) at diagnosis, or during follow-up. Overall, the probability of developing complicated disease behaviour was 49.7% and 61.3% in the pediatric and 55.1% and 62.4% in the adult onset patients after 5- and 10-years of follow-up. Similarly, time to change in disease behaviour from non stricturing, non penetrating (B1) to complicated, stricturing or penetrating (B2/B3) disease was not significantly different between pediatric and adult onset CD in a Kaplan-Meier analysis. Calendar year of diagnosis (P = 0.04), ileal location (P < 0.001), perianal disease (P < 0.001), smoking (P = 0.038) and need for steroids (P < 0.001) were associated with presence of, or progression to, complicated disease behavior at diagnosis and during follow-up. A change in disease location was observed in 8.9% of patients and it was associated with smoking status (P = 0.01), but not with age at diagnosis.

CONCLUSION

Long-term evolution of disease behavior was not different in pediatric- and adult-onset CD patients in this population-based cohort but was associated to location, perianal disease and smoking status.

Recommendations for identifying Crohn's disease patients with poor prognosis

Clinical presentation at diagnosis and the disease course of Crohn's disease is heterogeneous and variable over time. The majority of patients with Crohn's disease will develop at least one stricturing or perforating complication requiring surgery during follow-up. New data support a change in the natural history of the disease associated with the advent of biologicals and tailored treatment strategy. Therefore, it is important to identify patients at risk for disease progression as soon as possible. In recent years, much emphasis has been placed on determining important predictive factors. Complex evaluation of factors such as clinical and endoscopic presentation, fecal, serological and routine laboratory tests, and genetic factors is needed. This review summarizes the available evidence and will hopefully assist clinicians when choosing a treatment strategy in everyday practice.

Does smoking influence Crohn's disease in the biologic era? The TABACROHN study

BACKGROUND

While most studies have found a negative effect of smoking on Crohn's disease (CD) phenotype, more recent data have failed to reproduce this association, which might be due to a current wider use of thiopurines and biologic therapy. The TABACROHN study aimed at defining the impact of smoking on CD in the largest published series.

METHODS

This multicenter cross-sectional study included 1170 CD patients. Patients were classified as nonsmokers, current smokers, or former smokers according to their present smoking status. Clinical data regarding disease characteristics, treatment, and complications were collected.

RESULTS

Smokers were more frequently under maintenance treatment when compared to nonsmokers. In addition, current smokers presented higher use of biologic drugs compared to nonsmokers. Tobacco exposure and a higher tobacco load were independent predictors of need for maintenance treatment and stenosing phenotype, respectively.

CONCLUSIONS

In the era of early and widespread use of immunosuppressants and biologics, tobacco exposure is an independent predictor of need for maintenance treatment, specifically biologic therapy. The wider use of biologics and immunosuppressants could account for the existence of no major differences in disease behavior and complications between nonsmokers and current smokers.

Relationship between human intestinal dendritic cells, gut microbiota, and disease activity in Crohn's disease

BACKGROUND

Altered intestinal dendritic cell (DC) function underlies dysregulated T-cell responses to bacteria in Crohn's disease (CD) but it is unclear whether composition of the intestinal microbiota impacts local DC function. We assessed the relationship between DC function with disease activity and intestinal microbiota in patients with CD.

METHODS

Surface expression of Toll-like receptor (TLR)-2, TLR-4, and spontaneous intracellular interleukin (IL)-10, IL-12p40, IL-6 production by freshly isolated DC were analyzed by multicolor flow cytometry of cells extracted from rectal tissue of 10 controls and 28 CD patients. Myeloid DC were identified as CD11c(+) HLA-DR(+lin-/dim) cells (lin = anti-CD3, CD14, CD16, CD19, CD34). Intestinal microbiota were analyzed by fluorescent in situ hybridization of fecal samples with oligonucleotide probes targeting 16S rRNA of bifidobacteria, bacteroides-prevotella, C. coccoides-E. rectale, and Faecalibacterium prausnitzii.

RESULTS

DC from CD produced higher amounts of IL-12p40 and IL-6 than control DC. IL-6(+) DC were associated with the CD Activity Index (r = 0.425; P = 0.024) and serum C-reactive protein (CRP) (r = 0.643; P = 0.004). DC expression of TLR-4 correlated with disease activity. IL-12p40(+) DC correlated with ratio of bacteroides: bifidobacteria (r = 0.535, P = 0.003). IL-10(+) DC correlated with bifidobacteria, and IL-6(+) DC correlated negatively with F. prausnitzii (r = -0.50; P = 0.008). The amount of TLR-4 on DC correlated negatively with the concentration of F. prausnitzii.

CONCLUSIONS

IL-6 production by intestinal DC is increased in CD and correlates with disease activity and CRP. Bacterially driven local IL-6 production by intestinal DC may overcome regulatory activity, resulting in unopposed effector function and tissue damage. Intestinal DC function may be influenced by the composition of the commensal microbiota.

Anti-inflammatory effects of nicotine in obesity and ulcerative colitis

Cigarette smoke is a major risk factor for a number of diseases including lung cancer and respiratory infections. Paradoxically, it also contains nicotine, an anti-inflammatory alkaloid. There is increasing evidence that smokers have a lower incidence of some inflammatory diseases, including ulcerative colitis, and the protective effect involves the activation of a cholinergic anti-inflammatory pathway that requires the α7 nicotinic acetylcholine receptor (α7nAChR) on immune cells. Obesity is characterized by chronic low-grade inflammation, which contributes to insulin resistance. Nicotine significantly improves glucose homeostasis and insulin sensitivity in genetically obese and diet-induced obese mice, which is associated with suppressed adipose tissue inflammation. Inflammation that results in disruption of the epithelial barrier is a hallmark of inflammatory bowel disease, and nicotine is protective in ulcerative colitis. This article summarizes current evidence for the anti-inflammatory effects of nicotine in obesity and ulcerative colitis. Selective agonists for the α7nAChR could represent a promising pharmacological strategy for the treatment of inflammation in obesity and ulcerative colitis. Nevertheless, we should keep in mind that the anti-inflammatory effects of nicotine could be mediated via the expression of several nAChRs on a particular target cell.

Differences in inflammatory bowel disease phenotype between South Asians and Northern Europeans living in North West London, UK

OBJECTIVES

The incidence and prevalence of inflammatory bowel disease (IBD) is increasing throughout Asia. Since the 1950s, there has been substantial migration from South Asia (India, Pakistan, and Bangladesh) to the United Kingdom. The aim of this study was to define the clinical phenotype of IBD in UK South Asians living in North West London, and to compare the results with a white Northern European IBD cohort.

METHODS

The phenotypic details of 367 South Asian IBD patients (273 ulcerative colitis (UC) and 94 Crohn's disease (CD)), undergoing active follow-up in five North West London hospitals, were compared with those of 403 consecutively collected white Northern European IBD patients (188 UC and 215 CD).

RESULTS

The phenotype of IBD differed significantly between the two populations. 63.0% of South Asian UC patients had extensive colitis compared with 42.5% of the Northern European cohort (P < 0.0001). Proctitis was uncommon in South Asian UC patients (9.9 vs. 26.1% in Northern European patients, P<0.0001). In the South Asian CD cohort, disease location was predominantly colonic (46.8%). CD behavior differed significantly between the groups, with less penetrating disease compared with Northern Europeans (P=0.01) and a reduced need for surgery (P=0.003).

CONCLUSIONS

The phenotype of IBD in South Asians living in North West London is significantly different from that of a white Northern European IBD cohort. Knowledge of ethnic variations in disease phenotype may help to identify key genetic, environmental, and behavioral factors contributing to the development of IBD.

Is the disease course predictable in inflammatory bowel diseases?

During the course of the disease, most patients with Crohn's disease (CD) may eventually develop a stricturing or a perforating complication, and a significant number of patients with both CD and ulcerative colitis will undergo surgery. In recent years, research has focused on the determination of factors important in the prediction of disease course in inflammatory bowel diseases to improve stratification of patients, identify individual patient profiles, including clinical, laboratory and molecular markers, which hopefully will allow physicians to choose the most appropriate management in terms of therapy and intensity of follow-up. This review summarizes the available evidence on clinical, endoscopic variables and biomarkers in the prediction of short and long-term outcome in patients with inflammatory bowel diseases.

Early azathioprine/biological therapy is associated with decreased risk for first surgery and delays time to surgery but not reoperation in both smokers and nonsmokers with Crohn's disease, while smoking decreases the risk of colectomy in ulcerative colitis

BACKGROUND/AIMS

Smoking may alter the natural course of Crohn's disease (CD). Smokers are more likely to develop complications, relapses and have a greater risk for surgery. In contrast, in ulcerative colitis (UC), smoking might improve the disease course. Our aim was to assess the combined effect of disease phenotype, smoking, and immunomodulator [azathioprine (AZA), AZA/biological] treatment on the risk of intestinal resection/reoperation in CD and colectomy in UC.

PATIENTS/METHODS

Six hundred and eighty-one inflammatory bowel disease patients were analyzed (CD: 340, male/female: 155/185, duration: 9.4+/-7.5 years; UC: 341, male/female: 174/164, duration: 11.5+/-9.7 years). Patients were interviewed on their smoking habits at the time of diagnosis and during the regular follow-up visits. Medical records were retrospectively analyzed.

RESULTS

Smoking was present in 45.5% in CD and 15.8% in UC. CD patients who underwent at least one bowel resection comprised 46.5%. In an univariate analysis, disease location, behavior, AZA, or AZA/biological use before surgery [odds ratio (OR): 0.26 and 0.22, P<0.001] and smoking (OR: 1.61, P = 0.03) were associated with risk for first surgery. Smoking, AZA, or AZA/biological (P<0.001) use before first surgery and disease behavior were independently associated with risk for surgery in a proportional Cox-regression analysis. Perianal disease (OR: 3.2, P = 0.001) and frequent relapses (OR: 4.8, P<0.001) but not smoking, AZA, or AZA/biological use after first surgery were predictive for reoperation. In UC, the rate of colectomy was 5.6%. Disease location (P = 0.001) and smoking status (P = 0.02) were independently associated with risk for colectomy in a proportional Cox-regression analysis.

CONCLUSION

Our data suggest that early AZA/biological therapy reduces the risk for first operation but not reoperation in CD, in both smokers and nonsmokers. In contrast, smoking was associated with a decreased need for colectomy in UC.

Is the disease course predictable in inflammatory bowel diseases?

During the course of the disease, most patients with Crohn's disease (CD) may eventually develop a stricturing or a perforating complication, and a significant number of patients with both CD and ulcerative colitis will undergo surgery. In recent years, research has focused on the determination of factors important in the prediction of disease course in inflammatory bowel diseases to improve stratification of patients, identify individual patient profiles, including clinical, laboratory and molecular markers, which hopefully will allow physicians to choose the most appropriate management in terms of therapy and intensity of follow-up. This review summarizes the available evidence on clinical, endoscopic variables and biomarkers in the prediction of short and long-term outcome in patients with inflammatory bowel diseases.

[Prediction of the disease course in inflammatory bowel diseases]

Clinical presentation at diagnosis and disease course of both Crohn's disease (CD) and ulcerative colitis (UC) are heterogeneous and variable over time. During follow up, intestinal strictures or perforation may eventually develop at most patients with CD, and significant number of patients will undergo surgery. Much emphasis was laid in recent years on the determination of important predictive factors. Since early introduction of immunomodulators and/or biologicals might be justified in patients at risk for disease progression, so it is important to identify these patients as soon as possible. This review article summarizes the available literature on important clinical, endoscopic, fecal, serological/routine laboratory and genetic factors and hopefully will assist clinicians in the decision making of daily practice when choosing the treatment strategy for their patients with inflammatory bowel diseases.

Effects of tobacco smoke on immunity, inflammation and autoimmunity

Smoking is a central factor in many pathological conditions. Its role in neoplasm, lung and cardiovascular diseases has been well established for years. However it is less acknowledged the cigarette smoking affects both the innate and adoptive immune arms. Cigarette smoke was shown to augment the production of numerous pro-inflammatory cytokines such as TNF-alpha, IL-1, IL-6, IL-8 GM-CSF and to decrease the levels of anti-inflammatory cytokines such as IL-10. Tobacco smoke via multiple mechanisms leads to elevated IgE concentrations and to the subsequent development of atopic diseases and asthma. Cigarette smoke has also been shown activate in many ways macrophage and dendritic cell activity. While it is better evident how cigarette smoke evokes airway diseases more mechanisms are being revealed linking this social hazard to autoimmune disorders, for instance via the production of antibodies recognizing citrullinated proteins in rheumatoid arthritis or by the elevation of anti-dsDNA titers in systemic lupus erythematosus. The current review underlines the importance of smoking prevention and eradication not only in respiratory disorders but also in autoimmune conditions as well.

Perianal disease, small bowel disease, smoking, prior steroid or early azathioprine/biological therapy are predictors of disease behavior change in patients with Crohn's disease

AIM

To assess the combined effect of disease phenotype, smoking and medical therapy [steroid, azathioprine (AZA), AZA/biological therapy] on the probability of disease behavior change in a Caucasian cohort of patients with Crohn's disease (CD).

METHODS

Three hundred and forty well-characterized, unrelated, consecutive CD patients were analyzed (M/F: 155/185, duration: 9.4 +/- 7.5 years) with a complete clinical follow-up. Medical records including disease phenotype according to the Montreal classification, extraintestinal manifestations, use of medications and surgical events were analyzed retrospectively. Patients were interviewed on their smoking habits at the time of diagnosis and during the regular follow-up visits.

RESULTS

A change in disease behavior was observed in 30.8% of patients with an initially non-stricturing, non-penetrating disease behavior after a mean disease duration of 9.0 +/- 7.2 years. In a logistic regression analysis corrected for disease duration, perianal disease, smoking, steroid use, early AZA or AZA/biological therapy use were independent predictors of disease behavior change. In a subsequent Kaplan-Meier survival analysis and a proportional Cox regression analysis, disease location (P = 0.001), presence of perianal disease (P < 0.001), prior steroid use (P = 0.006), early AZA (P = 0.005) or AZA/biological therapy (P = 0.002), or smoking (P = 0.032) were independent predictors of disease behavior change.

CONCLUSION

Our data suggest that perianal disease, small bowel disease, smoking, prior steroid use, early AZA or AZA/biological therapy are all predictors of disease behavior change in CD patients.

Pancreatic cancer patients who smoke and drink are diagnosed at younger ages

BACKGROUND & AIMS

Cigarette smoking is an established risk factor for pancreatic cancer, but there is conflicting evidence regarding the effects of alcohol consumption. The effects of cigarettes and alcohol on age of sporadic pancreatic cancer diagnosis have not been examined; we evaluated the independent and synergistic effects of lifetime cigarette smoking and alcohol consumption on age at pancreatic cancer diagnosis in the United States.

METHODS

We analyzed data on cigarette smoking and alcohol consumption from the IMPAC Services, Inc Cancer Information Resource File (CIRF), collected from June 1, 1993, to December 31, 2003, for 29,239 reported, histologically confirmed cases of pancreatic adenocarcinoma. We also analyzed data on cigarette smoking and alcohol consumption for 820 histologically confirmed cases of pancreatic adenocarcinoma from the University of Michigan Pancreatic Cancer Registry (UMPCR), collected from January 2004 to October 2007.

RESULTS

Current cigarette smokers were diagnosed at significantly younger ages than never smokers, according to data from the CIRF and UMPCR (8.3 and 6.3 y, respectively); the UMPCR data indicated dose effects. Past and current alcohol consumption were associated with younger age at diagnosis in both databases. Current smokers who were current drinkers were diagnosed significantly earlier (CIRF, 10.2 y; UMPCR, 8.6 y) than abstainers. Past cigarette smoking was associated modestly with younger diagnosis age.

CONCLUSIONS

Cigarette smoking and alcohol consumption were associated with younger age at pancreatic cancer presentation and have a combined effect on diagnosis age. Past cigarette smoking is less influential. Smoking cessation programs could help prevent pancreatic cancer.

Effects of active and passive smoking on disease course of Crohn's disease and ulcerative colitis

BACKGROUND

Smoking is a remarkable risk factor for inflammatory bowel disease (IBD), aggravating Crohn's disease (CD) while having beneficial effects on ulcerative colitis (UC). We studied the effects of active and passive smoking in Dutch IBD patients.

METHODS

A questionnaire focusing on cigarette smoke exposure was sent to 820 IBD patients. Returned questionnaires were incorporated into a retrospective chart review, containing details about disease behavior and received therapy.

RESULTS

In all, 675 IBD patients (380 [56%] CD and 295 [44%] UC) responded. At diagnosis there were 52% smokers in CD, 41% in the general population, and 28% in UC. The number of present smokers in CD is lower than in the general population (26% versus 35%). No detrimental effects of active smoking on CD were observed, but passive smokers needed immunosuppressants and infliximab more frequently than nonpassive smokers. Active smoking had beneficial effects on UC, indicated by reduced rates of colectomy, primary sclerosing cholangitis, and backwash-ileitis in active smokers compared to never smokers, and higher daily cigarette dose correlated with less extensive colitis and a lower need for therapy. Furthermore, smoking cessation after diagnosis was detrimental for UC patients, indicated by increased needs for steroids and hospitalizations for patients that stopped smoking after compared to before the diagnosis.

CONCLUSIONS

Active smoking is a risk factor for CD, but does not affect the outcome; passive smoking is detrimental for the outcome of CD patients. In UC, active smoking shows dose-dependent beneficial effects. Our data suggest that passive smoking is a novel risk factor for CD.