Does active smoking really influence the course of Crohn's disease? A retrospective observational study

Can we change the natural course of inflammatory bowel disease?

Inflammatory bowel diseases (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), are lifelong diseases characterized by chronic inflammation of the gastrointestinal tract leading to its progressive and irreversible destruction. Whether early initiation of IBD-specific therapy impacts the long-term course of the disease remains unclear and has to be further explored in prospective disease-modification trials. Historically, surgery and hospitalization rates have been the surrogate markers to measure disease progression in IBD, providing an overview of the effectiveness of medical therapies. However, neither surgery nor hospitalization necessarily reflects a fail in therapeutic medical management, and many confounding factors make them biased outcomes. The Selecting Endpoints for Disease-Modification Trials consensus has defined the disease-modification endpoints required for these trials, including the impact of the disease on patient's life (health-related quality of life, disability, and fecal incontinence), the mid-term disease complications (bowel damage in CD, IBD-related surgery and hospitalizations, disease extension in UC, extra-intestinal manifestations, permanent stoma, short bowel syndrome), and the development of dysplasia/cancer and mortality in the long term. Most available data in the literature regarding the impact of current therapies on disease progression focused on anti-tumor necrosis factor agents and are based on retrospective or post-hoc studies. Thus, prospective disease-modification trials are pressingly required to explore the effectiveness of early intensified treatment in patients with severe disease or at risk for disease progression.

Prognostic biomarkers to identify patients likely to develop severe Crohn's disease: a systematic review

BACKGROUND

Identification of biomarkers that predict severe Crohn's disease is an urgent unmet research need, but existing research is piecemeal and haphazard.

OBJECTIVE

To identify biomarkers that are potentially able to predict the development of subsequent severe Crohn's disease.

DESIGN

This was a prognostic systematic review with meta-analysis reserved for those potential predictors with sufficient existing research (defined as five or more primary studies).

DATA SOURCES

PubMed and EMBASE searched from inception to 1 January 2016, updated to 1 January 2018.

REVIEW METHODS

Eligible studies were studies that compared biomarkers in patients who did or did not subsequently develop severe Crohn's disease. We excluded biomarkers that had insufficient research evidence. A clinician and two statisticians independently extracted data relating to predictors, severe disease definitions, event numbers and outcomes, including odds/hazard ratios. We assessed risk of bias. We searched for associations with subsequent severe disease rather than precise estimates of strength. A random-effects meta-analysis was performed separately for odds ratios.

RESULTS

In total, 29,950 abstracts yielded just 71 individual studies, reporting 56 non-overlapping cohorts. Five clinical biomarkers (Montreal behaviour, age, disease duration, disease location and smoking), two serological biomarkers (anti-Saccharomyces cerevisiae antibodies and anti-flagellin antibodies) and one genetic biomarker (nucleotide-binding oligomerisation domain-containing protein 2) displayed statistically significant prognostic potential. Overall, the strongest association with subsequent severe disease was identified for Montreal B2 and B3 categories (odds ratio 4.09 and 6.25, respectively).

LIMITATIONS

Definitions of severe disease varied widely, and some studies confounded diagnosis and prognosis. Risk of bias was rated as 'high' in 92% of studies overall. Some biomarkers that are used regularly in daily practice, for example C-reactive protein, were studied too infrequently for meta-analysis.

CONCLUSIONS

Research for individual biomarkers to predict severe Crohn's disease is scant, heterogeneous and at a high risk of bias. Despite a large amount of potential research, we encountered relatively few biomarkers with data sufficient for meta-analysis, identifying only eight biomarkers with potential predictive capability.

FUTURE WORK

We will use existing data sets to develop and then validate a predictive model based on the potential predictors identified by this systematic review. Contingent on the outcome of that research, a prospective external validation may prove clinically desirable.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016029363.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 45. See the NIHR Journals Library website for further project information.

Selecting End Points for Disease-Modification Trials in Inflammatory Bowel Disease: the SPIRIT Consensus From the IOIBD

BACKGROUND AND AIMS

Inflammatory bowel diseases (IBD), encompassing Crohn's disease (CD) and ulcerative colitis (UC), are chronic and disabling disorders. Prospective disease-modification trials to prevent disease progression are eagerly awaited. However, disease progression is not clearly defined. The objective of the Selecting End PoInts foR Disease-ModIfication Trials (SPIRIT) initiative was to achieve international expert consensus on the endpoints to be used in future IBD-disease modification trials.

METHODS

This initiative under the auspices of the International Organization for the Study of Inflammatory Bowel Diseases (IOIBD) began with a systematic literature search to evaluate the current evidence on the definition of disease progression in IBD. On October 22, 2019, a consensus meeting took place during the United European Gastroenterology Week (UEGW) Congress in Barcelona, during which predefined proposed statements were discussed in a plenary session and voted on anonymously. Agreement was defined as at least 75% of participants voting for any one statement.

RESULTS

The group agreed that the ultimate therapeutic goal in both CD and UC is to prevent disease impact on patient's life (health-related quality of life, disability, fecal incontinence), midterm complications (encompass bowel damage in CD, IBD-related surgery and hospitalizations, disease extension in UC, extraintestinal manifestations, permanent stoma, short bowel syndrome), and long-term complications (gastrointestinal and extraintestinal dysplasia or cancer, mortality).

CONCLUSIONS

Recommendations on which goals to achieve in disease-modification trials for preventing disease progression in patients with IBD are proposed by the SPIRIT consensus. However, these recommendations will require validation in actual clinical studies before implementation in disease-modification trials.

Long-Term Follow-Up, Association between CARD15/NOD2 Polymorphisms, and Clinical Disease Behavior in Crohn's Disease Surgical Patients

Background

CARD15/NOD2 is the most significant genetic susceptibility in Crohn's disease (CD) even though a relationship between the different polymorphisms and clinical phenotype has not been described yet. The study is aimed at analyzing, in a group of CD patients undergoing surgery, the relationship between CARD15/NOD2 polymorphisms and the clinical CD behavior after a long-term follow-up, in order to identify potential clinical biomarkers of prognosis.

Methods

191 surgical CD patients were prospectively characterized both for the main single nucleotide polymorphisms of CARD15/NOD2 and for many other environmental risk factors connected with the severe disease form. After a mean follow-up of 7.3 years, the correlations between clinical features and CD natural history were analyzed.

Results

CARD15/NOD2 polymorphisms were significantly associated with younger age at diagnosis compared to wild type cases (p < 0.05). Moreover, patients carrying a 3020insC polymorphism presented a larger Δ between diagnosis and surgery (p = 0.0344). Patients carrying an hz881 and a 3020insC exhibited, respectively, a lower rate of responsiveness to azathioprine (p = 0.012), but no difference was found in biologic therapy. Finally, the risk of surgical recurrence was significantly associated, respectively, to age at diagnosis, to familial CD history, to diagnostic delay, to arthritis, and to the presence of perioperative complications.

Conclusions

3020insC CARD15 polymorphism is associated with an earlier CD onset, and age at CD diagnosis < 27 years was confirmed to have a detrimental effect on its clinical course. In addition, the familiarity seems to be connected with a more aggressive postoperative course. Finally, for the first time, we have observed a lower rate of responsiveness to azathioprine in patients carrying an hz881 and a 3020insC.

Smoking Status at Diagnosis and Subsequent Smoking Cessation: Associations With Corticosteroid Use and Intestinal Resection in Crohn's Disease

BACKGROUND

The impact of smoking at diagnosis and subsequent smoking cessation on clinical outcomes in Crohn's disease (CD) has not been evaluated in a population-based cohort.

METHODS

Using a nationally representative clinical research database, we identified incident cases of CD between 2005 and 2014. We compared the following outcomes: overall corticosteroid (CS) use; flares requiring CS; CS dependency and intestinal surgery between smokers and non-smokers at time of CD diagnosis. Differences in these outcomes were also compared between persistent smokers and smokers who quit within 2 years of diagnosis.

RESULTS

We identified 3553 patients with a new CD diagnosis over the study period of whom 1121 (32%) were smokers. Smokers at CD diagnosis had significantly higher CS-use (56 versus 47%, p < 0.0001), proportionally more CS flares (>1 CS flare/year: 9 versus 6%, p < 0.0001), and higher CS dependency (27 versus 21%, p < 0.0001) than non-smokers. Regression analysis identified smoking at diagnosis to be associated with a higher risk of intestinal surgery (HR 1.64, 95% CI 1.16-2.52). There was a significantly higher proportion of 'quitters' who remained steroid-free through follow-up in comparison to 'persistent smokers' (45.4 versus 37.5%, respectively, p = 0.02). 'Quitters' also had lower rates of CS dependency compared to 'persistent smokers' (24 versus 33%, p = 0.008).

CONCLUSIONS

Smokers at CD diagnosis have higher CS-use, CS dependency and higher risk of intestinal surgery. Quitting smoking appears to have beneficial effects on disease related outcomes, including reducing CS dependency highlighting the importance of offering early smoking cessation support.

Current smoking improves ulcerative colitis patients' disease behaviour in the northwest of China

Introduction

The incidence of ulcerative colitis has increased tremendously over the past few decades, and caused much more attention in China. Several studies have revealed that both environmental and genetic factors play crucial roles in the formation and development of this disease. Among the environmental factors, the smoking condition is highly significant. Although current smoking has been associated with a protective effect on both the development and progression of ulcerative colitis (UC), the clinical characteristics of UC patients with current smoking in China is still unclear.

Aim

To clarify the relationship between current smoking and the UC in the northwest of China, patients diagnosed with ulcerative colitis in the General Hospital of Ningxia Medical University from 2003.03 to 2012.09 were assessed.

Material and methods

Data were collected about clinical features, cigarette smoking conditions, disease location, and therapeutic requirements. A total of 421 patients were included in this study, at diagnosis, 341 (81%) patients were non-smokers, and the current smokers amounted to 80 (19%).

Results

As for disease location, there were no differences between the current smokers and non-smokers regarding proctitis and extensive colitis, but the current smokers had less left-sided colitis than non-smokers (p = 0.049). Based on the Modified Mayo score, heavier smokers had lower scores than other smokers and non-smokers. For the therapeutic requirements, current smokers needed fewer corticosteroids than non-smokers (p = 0.048).

Conclusions

We found that current smoking is closely associated with a protective factor for UC.

The Faroese IBD Study: Incidence of Inflammatory Bowel Diseases Across 54 Years of Population-based Data

BACKGROUND AND AIMS

Inflammatory bowel diseases [IBDs] include Crohn's disease [CD], ulcerative colitis [UC], and IBD unclassified [IBDU]. In 2010 and 2011, the ECCO-EpiCom study found the worldwide highest incidence of inflammatory bowel disease [IBD] in the Faroe Islands: 83 per 100 000 [European Standard Population, ESP]. The present study assessed the long-term time trends in IBD incidence in the Faroese population.

METHODS

In this population-based study, data were retrieved from the National Hospital of the Faroe Islands and included all incident cases of CD, UC, and IBDU diagnosed between July 1960 and July 2014. Patients of all ages were included and diagnoses were defined according to the Copenhagen Diagnostic Criteria.

RESULTS

A total of 664 incident IBD patients were diagnosed: 113 with CD, 417 with UC, and 134 with IBDU. Of these, 51 [8%] were diagnosed with paediatric-onset IBD. Between 1960 and 1979, a total of 55 persons were diagnosed; 105 in 1980-89; 166 in 1990-99; 180 in 2000-09; and 158 in 2010-14. This represented an increase in the age-standardised IBD incidence rate from 7, 25, 40, and 42 to 74 per 100 000 [ESP]. For CD, the increase was from 1 to 10, for UC from 4 to 44, and for IBDU from 2 to 21 per 100 000 [ESP].

CONCLUSIONS

The high IBD incidence was found to be a relatively new phenomenon. The observed increase is unlikely to be an artefact resulting from, for instance, better registration. Our study indicated a real and increasing disease burden resulting from changing-so far unidentified-exposures.

Systematic review with meta-analysis: the adverse effects of tobacco smoking on the natural history of Crohn's disease

BACKGROUND

Tobacco smoking is a well-established risk factor for the development of Crohn's disease, and this may lead to a more complicated disease course. However, recent evidence suggests that many patients with Crohn's disease are unaware of this fact.

AIM

To perform a systematic review and meta-analysis of the effects of smoking on disease course in Crohn's disease.

METHODS

A search of MEDLINE, EMBASE and EMBASE classic was carried out (up to July 2015) to identify observational studies reporting data on smoking and rates of surgery or flares of disease activity in patients with Crohn's disease. Dichotomous data were pooled to obtain odds ratios (ORs) for flares of disease activity or need for surgery, with 95% confidence intervals (CIs).

RESULTS

The search identified 33 eligible studies. Compared with nonsmokers, smokers had increased odds of flare of disease activity (OR, 1.56; 95% CI, 1.21-2.01), flare after surgery (OR, 1.97; 95% CI, 1.36-2.85), need for first surgery (OR, 1.68; 95% CI, 1.33-2.12) and need for second surgery (OR, 2.17; 95% CI, 1.63-2.89). The odds of these outcomes among ex-smokers diminished upon smoking cessation, with ORs comparable to those among nonsmokers and, in the case of flare or second surgery, significantly lower than smokers.

CONCLUSIONS

Smokers with Crohn's disease have a more complicated disease course than nonsmokers, and quitting smoking may ameliorate this. Patients should be reminded of the detrimental effects of smoking on the course of their disease, and smoking cessation advice should be provided to reduce disease burden and costs in these patients.

Delayed diagnosis is influenced by the clinical pattern of Crohn's disease and affects treatment outcomes and quality of life in the long term: a cross-sectional study of 361 patients in Southern Italy

OBJECTIVES

Three patterns of Crohn's disease (CD) have been described. Our aim was to investigate for differences in diagnostic delay between patterns of CD, and differences in treatment outcomes, need for surgery and quality of life (QoL).

PATIENTS AND METHODS

This is a cross-sectional study. First, the data of CD patients observed at our IBD Referral Centre between 2000 and 2009 were analysed. We gathered demographical characteristics and data on the onset of clinical symptoms, progression until diagnosis and treatment. The risk of delayed diagnosis was computed for each pattern. We then asked patients to fill the Inflammatory Bowel Disease Questionnaire (IBDQ). QoL scores of patients receiving a diagnosis within 18 months from the onset of symptoms were matched with those of the remaining patients.

RESULTS

Three-hundred and sixty-one patients were identified. The mean age of the patients at the onset of symptoms and at diagnosis was 30 ± 14 and 32 ± 14 years. The penetrating pattern showed an association only with perianal symptoms at onset (P = 0.0015). The risk of delayed diagnosis was 21, 27 and 59% for inflammatory, stricturing and penetrating patterns. We found a significant difference between penetrating and nonpenetrating patterns (P = 0.043). A delayed diagnosis was associated with poorer treatment outcomes, QoL and higher surgery rate.

CONCLUSION

Our study suggests a correlation between delayed diagnosis and the CD pattern. The delay in diagnosis between the CD subtypes can influence outcomes and QoL.

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.

An overview of the natural history of inflammatory bowel diseases

Inflammatory bowel disease includes two main conditions: Crohn's disease (CD) and ulcerative colitis (UC). Natural history studies of these two entities have shown relevant differences in several clinical outcomes, mainly a more chronic and persistent (although often subclinical) inflammatory activity and the development of complications related to long-term tissue damage in CD. This led in recent years to different long-term therapeutic strategies in each disease. In this article, we review the main phenotypic features of UC and CD at the time of disease diagnosis and their changes along the course of the disease, as well as their consequences regarding drug therapy and surgical requirements.

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.