A meta-analysis of the role of smoking in inflammatory bowel disease

REGENT: a risk assessment and classification algorithm for genetic and environmental factors

The identification of environmental and genetic factors that contribute to disease risk requires appropriate statistical methods and software that can integrate different sources of risk, provide statistical assessment of combined risk factors, and facilitate interpretation of this risk. We have developed an R package, REGENT, to calculate risks conferred by genetic factors and multilevel environmental factors. This is performed at a population level, with the option to also analyse individual-level data. REGENT incorporates variability in risk factors to calculate confidence intervals for risk estimates and to classify the population into different categories of risk based on significant differences from the baseline average member of the population. REGENT is an R package available from CRAN: http://cran.r-project.org/web/packages/REGENT. It will be of value to genetic researchers exploring the utility of the variants detected for their disorder, and to clinical researchers interested in genetic risk studies.

The relationship between urban environment and the inflammatory bowel diseases: a systematic review and meta-analysis

BACKGROUND

The objective of this study was to conduct a systematic review with meta-analysis of studies assessing the association between living in an urban environment and the development of the Crohn's disease (CD) or ulcerative colitis (UC).

METHODS

A systematic literature search of MEDLINE (1950-Oct. 2009) and EMBASE (1980-Oct. 2009) was conducted to identify studies investigating the relationship between urban environment and IBD. Cohort and case-control studies were analyzed using incidence rate ratio (IRR) or odds ratio (OR) with 95 % confidence intervals (CIs), respectively. Stratified and sensitivity analyses were performed to explore heterogeneity between studies and assess effects of study quality.

RESULTS

The search strategy retrieved 6940 unique citations and 40 studies were selected for inclusion. Of these, 25 investigated the relationship between urban environment and UC and 30 investigated this relationship with CD. Included in our analysis were 7 case-control UC studies, 9 case-control CD studies, 18 cohort UC studies and 21 cohort CD studies. Based on a random effects model, the pooled IRRs for urban compared to rural environment for UC and CD studies were 1.17 (1.03, 1.32) and 1.42 (1.26, 1.60), respectively. These associations persisted across multiple stratified and sensitivity analyses exploring clinical and study quality factors. Heterogeneity was observed in the cohort studies for both UC and CD, whereas statistically significant heterogeneity was not observed for the case-control studies.

CONCLUSIONS

A positive association between urban environment and both CD and UC was found. Heterogeneity may be explained by differences in study design and quality factors.

The relationship between urban environment and the inflammatory bowel diseases: a systematic review and meta-analysis

Background

The objective of this study was to conduct a systematic review with meta-analysis of studies assessing the association between living in an urban environment and the development of the Crohn’s disease (CD) or ulcerative colitis (UC).

Methods

A systematic literature search of MEDLINE (1950-Oct. 2009) and EMBASE (1980-Oct. 2009) was conducted to identify studies investigating the relationship between urban environment and IBD. Cohort and case–control studies were analyzed using incidence rate ratio (IRR) or odds ratio (OR) with 95 % confidence intervals (CIs), respectively. Stratified and sensitivity analyses were performed to explore heterogeneity between studies and assess effects of study quality.

Results

The search strategy retrieved 6940 unique citations and 40 studies were selected for inclusion. Of these, 25 investigated the relationship between urban environment and UC and 30 investigated this relationship with CD. Included in our analysis were 7 case–control UC studies, 9 case–control CD studies, 18 cohort UC studies and 21 cohort CD studies. Based on a random effects model, the pooled IRRs for urban compared to rural environment for UC and CD studies were 1.17 (1.03, 1.32) and 1.42 (1.26, 1.60), respectively. These associations persisted across multiple stratified and sensitivity analyses exploring clinical and study quality factors. Heterogeneity was observed in the cohort studies for both UC and CD, whereas statistically significant heterogeneity was not observed for the case–control studies.

Conclusions

A positive association between urban environment and both CD and UC was found. Heterogeneity may be explained by differences in study design and quality factors.

Chronic intestinal inflammation: inflammatory bowel disease and colitis-associated colon cancer

The inflammatory bowel diseases (IBD), including Crohn’s disease (CD) and ulcerative colitis (UC), are chronic inflammatory disorders of the intestine. The prevalence in the United States is greater than 200 cases per 100,000, with the total number of IBD patients between 1 and 1.5 million. CD may affect all parts of the gastrointestinal tract, from mouth to anus, but most commonly involves the distal part of the small intestine or ileum, and colon. UC results in colonic inflammation that can affect the rectum only, or can progress proximally to involve part of or the entire colon. Clinical symptoms include diarrhea, abdominal pain, gastrointestinal bleeding, and weight loss. A serious long-term complication of chronic inflammation is the development of colorectal cancer. A genetic basis for IBD had long been recognized based on the increased familial risk. However, significant discordance for CD in twins, and a much less robust phenotypic concordance for UC, suggested additional factors play a role in disease pathogenesis, including environmental factors. In the past several years, progress in understanding the molecular basis of IBD has accelerated, beginning with the generation of animal models of colitis and progressing to the identification of specific genetic markers from candidate gene, gene linkage, and genome-wide association analyses. Genetic studies have also resulted in the recognition of the importance of environmental factors, particularly the crucial role of the gut microbiota in CD and UC. Altered immune responses to the normal intestinal flora are key factors in IBD pathogenesis. In this research topic, the genetic basis of IBD, the genetic and cellular alterations associated with colitis-associated colon cancer, and the emerging role of the intestinal microbiota and other environmental factors will be reviewed.

[Hungarian data on inflammatory bowel diseases: analytical data on ulcerative colistis]

Prospective data collection seems to be essential in evidence-based medicine. Because of the new therapeutic options, the need for standard data collection and testing has significantly increased. In Hungary, a registry for patients with inflammatory bowel disease has already been set up, which makes it possible for clinicians to collect prospective data on their patients.

AIM

Basic characteristics of the database of patients with ulcerative colitis are presented in this paper.

METHODS

The inflammatory bowel disease registry uses the programme of Microsoft Access database management system. Data are stored in a central server.

RESULTS

The incidence of inflammatory bowel diseases has been permanently increasing in Hungary; however, its overall prevalence is still low among the European countries. The frequent administration of immunosuppressive medications (azathioprine and corticosteroids) and their increased doses worsen the estimation of the activity.

CONCLUSIONS

1., It would be very useful to gain prospective data from all national centres. This kind of database would be able to give a complete picture regarding the Hungarian therapeutical practice. 2., Medications of patients may alter the clinical value of the laboratory findings in the process of determining the severity of the disease.

Assessment of variables associated with smoking cessation in Crohn's disease

BACKGROUND

Patients with Crohn's disease (CD) who smoke have a more complicated disease course.

AIMS

Our primary objective was to assess smoking related variables that were associated with smoking cessation versus continued smoking in patients with CD.

METHODS

A multi-center study identified CD patients who were seen at the University of Chicago and University of Calgary IBD clinics. Patients were categorized into three subgroups: lifetime non-smokers, current smokers, or ex-smokers. Participants completed questionnaires assessing their cigarette smoking behavior. Current smokers were prospectively followed for 6 months to assess smoking status and attempts to quit. Logistic regression analysis was performed to identify factors associated with smoking cessation.

RESULTS

Three hundred patients were enrolled with 148 identifying themselves as lifetime non-smokers, 70 as current smokers, and 82 as ex-smokers. Patients who reported their first cigarette within 5 min of waking were more likely to be current smokers (OR = 21; 95% CI 3.94-107.3) as compared to patients who waited greater than 60 min. Current smokers were more likely to have one or more household members who smoked compared to ex-smokers (P < 0.05). Nearly half (49%) of the current smokers were in the precontemplation stage of change (i.e. no intention to quit smoking). At the 6-month follow-up, only 11% reported they quit smoking.

CONCLUSIONS

Patients who report a short time to first cigarette in the morning may have more difficulty in smoking cessation. Current smokers were more likely to have another smoker in the household compared to ex-smokers. Current smokers had low levels of motivation to quit smoking and consequently with no intervention, very few quit 6 months after the baseline assessment.

A case-only study of gene-environment interaction between genetic susceptibility variants in NOD2 and cigarette smoking in Crohn's disease aetiology

Background

Genetic variation in NOD2 and cigarette smoking are well-established risk factors for the development of Crohn's disease (CD). However, little is known about a potential interaction between these risk factors. We investigated gene-environment interactions between CD-associated NOD2 alleles and cigarette smoking in a large sample of patients with CD.

Methods

Three previously reported CD-associated variants in NOD2 (R702W, G908R, 1007fs) were genotyped in 1636 patients with CD continuously recruited between 1995 and 2010 based on physician referral. Data on history of smoking behaviour was obtained for all participants through a written questionnaire. Using a case-only design, we performed logistic regression analyses to investigate statistical interactions between NOD2 risk alleles and smoking status.

Results

We detected a significant negative interaction between carriership of at least one of the NOD2 risk alleles and history of ever having smoked (OR = 0.71; p = 0.005) as well as smoking at the time of CD diagnosis (OR = 0.68; p = 0.005). Subsequent separate analyses of the three variants revealed a significant negative interaction between the 1007fs variant and history of ever having smoked (OR = 0.64; p = 9 × 10^-4) and smoking at the time of CD diagnosis (OR = 0.53; p = 7 × 10^-5).

Conclusions

The observed significant negative gene-environment interaction suggests that the risk increase for CD conferred simultaneously by cigarette smoking and the 1007fs NOD2 polymorphism is smaller than expected and may point to a biological interaction. Our findings warrant further investigation in epidemiological and functional studies to elucidate pathophysiology as well as to aid in the development of recommendations for disease prevention.

Nicotine modulates the immunological function of dendritic cells through peroxisome proliferator-activated receptor-γ upregulation

We examined the effects of nicotine on differentiation and function of monocyte-derived human dendritic cells (DCs). NiDCs, which were the DCs differentiated in the presence of nicotine, showed lower levels of CD1a. Secretion of IL-12 and TNF-α by lipopolysaccharide (LPS)-stimulated NiDCs was significantly suppressed compared to monocyte-derived DCs grown without nicotine. NiDCs displayed a diminished capacity to induce allogeneic T cell proliferation with a reduced production of IFN-γ, and maintained/enhanced LPS-mediated expression of coinhibitory molecules. Interestingly, NiDCs enhanced the expression of nuclear receptor peroxisome proliferator-activated receptors γ (PPAR γ), which has immunomodulatory properties. Expression of PPAR γ and PPAR γ-target genes was significantly inhibited by pretreatment with d-tubocurarine, antagonist of non-selective nicotinic acetylcholine receptors (nAChR). In addition, reduction of Th1 responses was inhibited after blocking nAChR-mediated signal. These data suggest the effect of nicotine on altering DC immunogenicity by impeding Th1 immunity is partially mediated by upregulation of PPAR γ.

The association between smoking and the development of psoriatic arthritis among psoriasis patients

AIM

To investigate the association between smoking and psoriatic arthritis (PsA) among patients with psoriasis and its interaction with the HLA-C*06 allele.

METHODS

In this exploratory case-control study, smoking status was determined at the time of the diagnosis of arthritis for PsA patients and at their first study visit for psoriasis patients, when they were confirmed not to have PsA. The proportions of patients exposed to smoking were compared in patients with PsA to those with psoriasis alone. A logistic regression model was constructed to test the independent association of smoking and PsA after adjusting for potential confounders. The statistical interaction between HLA-C*06 and smoking was tested through a regression model.

RESULTS

The proportions of current and past smokers were higher in the psoriasis group compared with the PsA group (30.2% vs 23.4% and 26.7% vs 22.3%, p=0.001, respectively). On multivariate analysis being a current smoker versus a lifetime non-smoker remained inversely associated with PsA (OR 0.57, p=0.002), while past smoker versus lifetime non-smoker status was no longer significant. In a subgroup analysis, smoking remained inversely associated with PsA only among patients who were HLA-C*06 negative. Regression analysis revealed that the interaction between smoking status (ever smoked vs lifetime non-smoker) and HLA-C*06 was statistically significant (p=0.01).

CONCLUSION

Smoking may be inversely associated with PsA among psoriasis patients. This association is not present among HLA-C*06-positive individuals.

[The Fetal Tobacco Syndrome - A statement of the Austrian Societies for General- and Family Medicine (ÖGAM), Gynecology and Obstetrics (ÖGGG), Hygiene, Microbiology and Preventive Medicine (ÖGHMP), Pediatrics and Adolescence Medicine (ÖGKJ) as well as Pneumology (ÖGP)]

Over more than 50 years, the nocuous effects of smoking in pregnancy on the fetus are well known. In the first years of science the focus was primarily on restricted fetal growth while in more recent years over 10.000 studies investigated the incomparably big sum of detrimental effects for the unborn's health. In this statement we want to present the recent scientific findings on this topic. The statement is aimed to show all doctors who treat pregnant women the present situation and evidence. In the beginning we give a short overview about the epidemiological situation in Europe. Then we present step by step the health effects with regards to pathophysiology and clinics. Furthermore the reader will learn about possibilities for smoking cessation in pregnancy. The problem of passive-smoking in pregnancy will be dealt with in a separate chapter. At present there is strong evidence that pregnant smoking has a detrimental effect on birth-weight, placenta-associated disease, stillbirth, sudden infant death syndrome (SIDS), childhood overweight, clefts, lung function, asthma, cardiovascular diseases and mental developmental disorders. These factors can be summarized by the term Fetal Tobacco Syndrome. There is supply for more studies for less investigated health effects. Pregnancy is a chance to stop smoking as most women show a high motivation in this period. Hence doctors of all disciplines should inform pregnant women about the detrimental effects of smoking on their unborn child and show them possibilities for smoking cessation.

The potential value of faecal lactoferrin as a screening test in hospitalized patients with diarrhoea

BACKGROUND

Nosocomial diarrhoea is common and its investigation carries a significant healthcare cost. This study aimed to determine the utility of faecal lactoferrin (FL), a readily measurable marker of intestinal inflammation, in hospitalized patients with diarrhoea.

METHODS

FL was quantified in consecutive faecal samples submitted to a hospital pathology laboratory. Patient data were extracted from hospital records. Receiver-operator curve (ROC) analysis was performed in a subset of patients where a decision about low or high likelihood of inflammation could be confidently made. Multivariate analyses were performed to identify associations with an elevated FL. Cost analyses were also performed.

RESULTS

A total of 511 faecal samples from 433 patients (48% male, median age 67 years) was studied. Median FL concentration was 3.4 µg/mL (range 0-288). ROC analysis indicated an optimal cut-off value of 1.25 µg/mL (sensitivity 92%, specificity 97%, negative predictive value 97%) compared with the manufacturer's cut-off of 7.25 µg/mL (60%, 66% and 85% respectively). Multivariate analysis at the lower cut-off minimized potentially confounding variables. Proton pump inhibitor use independently increased (OR 2.3, 95% CI 1.5-3.8) and current smoking reduced (0.61, 0.38-0.99) the likelihood of an elevated FL. Only one out of 32 bacteriological positive samples would have been missed if FL was instituted as a screening test prior to microbiological assessment, which could have reduced laboratory-related costs by up to 56%.

CONCLUSION

In hospitalized patients, a normal FL effectively excludes inflammatory diarrhoea and is proposed as a screening test prior to microbiological assessment of faeces. Prospective evaluation of this approach is warranted.

Aspirin in the aetiology of Crohn's disease and ulcerative colitis: a European prospective cohort study

BACKGROUND

Aspirin has detrimental effects on the gastrointestinal tract mucosa and may play a role in the aetiology of inflammatory bowel disease.

AIM

To investigate if the regular use of aspirin is associated with the development of Crohn's disease (CD) and ulcerative colitis (UC) using, for the first time, a prospective cohort study design.

METHODS

A total of 135,780 men and women in Europe, aged 30-74years, were recruited into the European Prospective Investigation into Cancer and Nutrition study. Participants completed questionnaires at baseline detailing their regular aspirin use and were then followed up to identify those who developed either incident CD or UC. Each case was matched with four controls and odds ratios (OR) were calculated, adjusting for cigarette smoking. Potential interactions between aspirin and smoking were assessed.

RESULTS

A total of 35 participants developed CD and a further 84 were diagnosed with UC. Regular aspirin intake was positively associated with the risk of developing CD (OR=6.14, 95% CI=1.76-21.35). In those who took aspirin and smoked there was no detectable increased risk of CD (OR=0.30, 95% CI=0.03-3.08). No association was found between regular aspirin use and UC (OR=1.29, 95% CI=0.67-2.46).

CONCLUSIONS

A strong positive association between regular aspirin use and CD, but not UC, was observed. The data suggest that regular aspirin use should be measured in epidemiological work on CD. If such findings are consistent in other work then aspirin may affect the development of CD in a middle-aged to elderly population.

Management of Crohn's disease in smokers: is an alternative approach necessary?

Inflammatory bowel disease is a chronic condition with a pathogenic background that involves both genetic and environmental factors. Although important progress has been made regarding the former in the last decade, scarce knowledge is available for the latter. In this sense, smoking remains the most important environmental factor in IBD. Active smoking increases the risk of developing Crohn's disease (CD). Moreover, CD patients who start or continue smoking after disease diagnosis are at risk for poorer outcomes such as higher therapeutic requirements and disease-related complications, as compared to those patients who quit smoking or who never smoked. However, the harmful effect of active smoking is not uniform in all patients or in all clinical scenarios. Interventions designed to facilitate smoking cessation may impact the course of the disease. In this article, the available evidence of the deleterious effects of smoking on CD is reviewed in detail, and alternative therapeutic approaches to CD in smokers are proposed.

Challenges associated with identifying the environmental determinants of the inflammatory bowel diseases

In the last several years there has been an explosion in the discovery of inflammatory bowel disease (IBD) susceptibility genes; however, similar advances in identifying and defining environmental risk factors associated with IBD have lagged behind. Moreover, many studies that have explored the same or similar environmental risk factors of IBD have demonstrated disparate results and come to conflicting conclusions. In order for the field to move forward, it is important to understand and resolve why these differences exist. This significant heterogeneity has blurred the identification of the fundamental environmental determinants of IBD. The purpose of this review article is to explore the factors that have likely contributed to the heterogeneity among observational studies of environmental risk factors in IBD. In doing so, it is hoped that methodological standardization may lead to consistent environmental associations.

Non-Jewish Israeli IBD patients have significantly higher glutathione S-transferase GSTT1-null frequency

BACKGROUND

The involvement of oxidant/antioxidant imbalance in the development of inflammatory bowel disease (IBD) is well documented. Two members of the glutathione S-transferase (GST) family of enzymes, GSTM1 and GSTT1, known to take part in cellular protection against electrophiles, demonstrate common deletion variants (termed null) associated with impaired enzyme function.

AIM

To evaluate the effect of GSTM1/GSTT1 genotype on IBD susceptibility in a Israeli cohort and to study the correlation between GSTM1/GSTT1 genotype, smoking status, and a variety of clinical characteristics of IBD.

METHODS

A cohort of 606 Israeli IBD patients (453 with Crohn's disease [CD] and 153 with ulcerative colitis [UC]) and 528 ethnically matched healthy controls were genotyped for the null variants of GSTM1 and GSTT1. In patients, phenotype-genotype correlations were examined.

RESULTS

Ethnic stratification of healthy controls revealed a higher frequency of GSTT1-null in Jewish and Arab Moslem individuals compared to Druze individuals (P < 0.0005), but no difference in GSTM1-null was found. Comparing IBD patients (both CD and UC) to healthy controls revealed a pattern of lower GSTM1-null and higher GSTT1-null frequencies, which reached significance in Arab Moslem patients. No association was found between NOD2/CARD15 mutation carriage and GSTM1/GSTT1 genotype. No statistically significant association was found between GSTT1-null or GSTM1-null, smoking status, and other phenotypes of CD/UC.

CONCLUSIONS

GSTT1-null appears to be associated with IBD, while GSTM1-null appears to be conversely associated with IBD. No association was found between GSTT1-null or GSTM1-null and specific IBD phenotypes.

Smoking inhibits the frequency of bronchovascular bundle thickening in sarcoidosis

RATIONALE/OBJECTIVES

Smoking has been associated with decreased incidence and prevalence of sarcoidosis, but few studies have evaluated effects of smoking on clinical parameters of the disease. The objectives were to determine the association of smoking with radiographic patterns and to evaluate the associations of these smoking-related radiographic patterns on airflow obstruction in sarcoidosis.

MATERIALS AND METHODS

Clinical data and computed tomography (CT) scans of 124 patients with sarcoidosis were reviewed. CT scans were assessed for lymph nodes, nodules, bronchiectasis, bronchovascular bundle thickening, displaced hilum, fibrosis, ground glass, emphysema, pleural changes, and alveolar opacities. CT patterns were compared between patients with and without a history of smoking. The effect of smoking on the associations between radiographic patterns and airflow obstruction was assessed with multivariable analysis.

RESULTS

Smokers had less frequency of bronchovascular bundle thickening than nonsmokers (11/38 subjects [29%] vs 50/86 subjects [58%], P = .003) and more emphysema (7/38 subjects [18%] vs 1/86 subjects [1%], P = .001). Patients who had bronchovascular bundle thickening were less likely to have ever smoked (11/61 subjects [18%] vs 27/63 subjects [43%], P = .003) or be current smokers (4/61 subjects [7%] vs 15/63 subjects [24%], P = .008). Age (P = .003) and bronchovascular bundle thickening (P = .02) were independent predictors of airflow obstruction. There were no differences in smoking history between patients with airflow obstruction versus those without (10/37 subjects [27%] vs 28/87 subjects [32%], P = .63).

CONCLUSIONS

In patients with sarcoidosis, smoking is associated with decreased frequency of bronchovascular bundle thickening, an important clinical manifestation of the lung disease. Further, bronchovascular bundle thickening and age are the only independent predictors of airflow obstruction, and smoking does not confound these associations.

What can we learn about biofilm/host interactions from the study of inflammatory bowel disease

OBJECTIVES

The aim of this review was to evaluate possible common pathogenic pathways and risk factors in inflammatory bowel disease (IBD) and periodontitis.

MATERIALS AND METHODS

A MEDLINE-PubMed research was conducted.

RESULTS

The pathogenesis of both diseases is multi-factorial leading to a substantial defect of the mucosal barrier, deregulation of the immune response and chronic inflammation of the mucosa. Environmental factors, particularly bacteria, are key factors in the pathogenesis of both diseases. Genetic predisposition is a key factor in the IBD pathogenesis, while a clear role of genetics in the pathogenesis of periodontitis is still unclear. The immune response in IBD is mediated by T lymphocytes as a consequence of a genetic trait associated with T-cell deregulation. On the other hand, in periodontitis plasma cells and lymphocytes are the predominant cells in the chronic inflammatory lesion, with the presence of B cells being proportionally larger than T cells.

CONCLUSION

IBD and periodontitis share several factors in their aetiology and pathogenesis, although they also have distinct characteristics.

Familial aggregation in inflammatory bowel disease: Is it genes or environment?

Inflammatory bowel disease (IBD) develops in genetically susceptible individuals due to the influence of environmental factors, leading to an abnormal recognition of microbiota antigens by the innate immune system which triggers an exaggerated immune response and subsequent bowel tissue damage. IBD has been more frequently found in families, an observation that could be due to either genetic, environmental or both types of factors present in these families. In addition to expanding our knowledge on IBD pathogenesis, defining the specific contribution to familial IBD of each one of these factors might have also clinical usefulness. We review the available evidence on familial IBD pathogenesis.

Ulcerative colitis in smokers, non-smokers and ex-smokers

Smoking is a major environmental factor that interferes in the establishment and clinical course of ulcerative colitis (UC). Firstly, the risk of smoking status impact in the development of UC is reviewed, showing that current smoking has a protective association with UC. Similarly, being a former smoker is associated with an increased risk of UC. The concept that smoking could have a role in determining the inflammatory bowel disease phenotype is also discussed. Gender may also be considered, as current smoking delays disease onset in men but not in women. No clear conclusions can be driven from the studies trying to clarify whether childhood passive smoking or prenatal smoke exposure have an influence on the development of UC, mainly due to methodology flaws. The influence of smoking on disease course is the second aspect analysed. Some studies show a disease course more benign in smokers that in non-smokers, with lower hospitalizations rates, less flare-ups, lower use of oral steroids and even less risk of proximal extension. This is not verified by some other studies. Similarly, the rate of colectomy does not seem to be determined by the smoking status of the patient. The third issue reviewed is the use of nicotine as a therapeutic agent. The place of nicotine in the treatment of UC is unclear, although it could be useful in selected cases, particularly in recent ex-smokers with moderate but refractory attacks of UC. Finally, the effect of smoking cessation in UC patients is summarised. Given that smoking represents a major worldwide cause of death, for inpatients with UC the risks of smoking far outweigh any possible benefit. Thus, physicians should advise, encourage and assist UC patients who smoke to quit.

Smoking and Barrett's esophagus in women who undergo upper endoscopy

BACKGROUND

Cigarette use is associated with esophageal adenocarcinoma, and cross-sectional studies suggest an association between smoking and Barrett's esophagus.

AIMS

We sought to examine prospectively the effect of smoking on the risk for Barrett's esophagus.

METHODS

This was a prospective cohort study among 20,863 women within the Nurses' Health Study who underwent upper gastrointestinal endoscopy for any reason between 1980 and 2006. We assessed the association between smoking and pathologically-confirmed Barrett's esophagus (n = 377). Self-reported data on smoking and potential confounding variables were collected from biennial questionnaires.

RESULTS

Compared with women who never smoked, former smokers of 1-24 cigarettes/day had a multivariate odds ratio for Barrett's esophagus of 1.25 (95% CI 0.99-1.59), former smokers of ≥ 25 cigarettes/day had a multivariate odds ratio of 1.52 (95% CI 1.04-2.22), current smokers of 1-24 cigarettes/day had a multivariate odds ratio of 0.89 (95% CI 0.54-1.45), and current smokers of ≥ 25 cigarettes/day had a multivariate odds ratio of 0.92 (95% CI 0.34-2.54). The risk for Barrett's esophagus increased significantly with increasing pack-years smoked among former (P = 0.008) but not current smokers (P = 0.99), especially when considering exposure ≥ 25 years before index endoscopy. Results were similar among women reporting regular heartburn/acid-reflux one or more times a week, and were not accounted for by changes in weight.

CONCLUSIONS

Heavy, remote smoking is associated with an increased risk for Barrett's esophagus. This finding suggests a long latency period between exposure and development of the disease, even after discontinuation of smoking.

Role of the xenobiotic receptor in inflammatory bowel disease

BACKGROUND

Gene-environment interplay modulates inflammatory bowel diseases (IBD). Dioxin-like compounds can activate the aryl hydrocarbon receptor (AhR) and alter macrophage function as well as T-cell polarization. We hypothesized that attenuation of the AhR signaling pathway will ameliorate colitis in a murine model of IBD.

METHODS

Dextran sulfate sodium (DSS) colitis was induced in C57BL/6 AhR null mice (AhR(-/-) ), heterozygous mice (AhR(-/+) ), and their wildtype (WT) littermates. Clinical and morphopathological parameters were used to compare the groups.

PATIENTS

AhR pathway activation was analyzed in biopsy specimens from 25 IBD patients and 15 healthy controls.

RESULTS

AhR(-/-) mice died before the end of the treatment. However, AhR(-/+) mice exhibited decreased disease activity compared to WT mice. The AhR(-/+) mice expressed less proinflammatory cytokines such as tumor necrosis factor alpha (TNF-α) (6.1- versus 15.7-fold increase) and IL17 (23.7- versus 67.9-fold increase) and increased antiinflammatory IL-10 (2.3-fold increase) compared with the AhR(+/+) mice in the colon. Colonic macrophage infiltration was attenuated in the AhR(-/+) group. AhR and its downstream targets were significantly upregulated in IBD patients versus control (CYP1A1 -19.9, and IL8- 10-fold increase).

CONCLUSIONS

Attenuation of the AhR receptor expression resulted in a protective effect during DSS-induced colitis, while the absence of AhR exacerbated the disease. Abnormal AhR pathway activation in the intestinal mucosa of IBD patients may promote chronic inflammation. Modulation of AhR signaling pathway via the diet, cessation of smoking, or administration of AhR antagonists could be viable strategies for the treatment of IBD.

Smoking and the risk of diverticular disease in women

Background

The relationship between smoking and the risk of diverticular disease is unclear. An observational cohort study was undertaken to investigate the association between smoking and diverticular disease.

Methods

Women in the Swedish Mammography Cohort born between 1914 and 1948 were followed from 1997 to 2008. Information on smoking and other lifestyle factors was collected through questionnaires. Patients with symptomatic diverticular disease were identified from Swedish national registers. Relative risks (RRs) of symptomatic diverticular disease (resulting in hospital admission or death) according to smoking status were estimated using Cox proportional hazards models.

Results

Of 35 809 women included in the study, 561 (1·6 per cent) had symptomatic diverticular disease. In multivariable analysis, current smokers had an increased risk of symptomatic diverticular disease compared with non-smokers after adjustment for age, intake of dietary fibre, diabetes, hypertension, use of acetylsalicylic acid, non-steroidal anti-inflammatory drugs or steroid medication, alcohol consumption, body mass index, physical activity and level of education (RR 1·23, 95 per cent confidence interval 0·99 to 1·52). Past smokers also had an increased risk (RR 1·26, 1·02 to 1·56). Smokers had a higher risk of developing a diverticular perforation/abscess than non-smokers (RR 1·89, 1·15 to 3·10).

Conclusion

Smoking is associated with symptomatic diverticular disease.

Smoking status and response to thiopurines in steroid-dependent inflammatory bowel disease

BACKGROUND

The influence of smoking on inflammatory bowel disease (IBD) susceptibility and on its clinical course is well known, but not its impact on drug efficacy. The aim of this study was to evaluate the response to thiopurines in patients with steroid-dependent IBD according to their smoking habits.

METHODS

The medical records of 163 IBD patients (103 Crohn's disease [CD], 60 ulcerative colitis [UC]) in whom thiopurines were started because of steroid-dependency were reviewed. Therapeutic response was defined by steroid-free clinical remission for at least 6 months after 12 months of starting thiopurines. Clinical data and smoking status at diagnosis, at the time thiopurines were started, and during the follow-up were registered.

RESULTS

A therapeutic response was obtained in 72% of CD and 61% of UC patients. Smoking habits did not influence the rate of response to thiopurines, the need for rescue therapies, or the development of penetrating/stricturing complications (CD) or proximal progression (UC). However, CD responders who continued smoking required new courses of steroids more often during follow-up. No influence of smoking was found when these outcomes were analyzed depending on gender or disease location. In the multivariate analysis, smoking status was the only predictive factor of drug tolerance.

CONCLUSIONS

Active smoking does not influence the response to thiopurines in steroid-dependent IBD, but may decrease the likelihood of drug tolerance.

Investigational new drugs in the treatment of inflammatory bowel disease: a review

The unraveling of the immuno-pathobiology of inflammatory bowel disease (IBD) in the past three decades has ushered in a new era of translational medicine. The biotechnology revolution has resulted in a paradigm shift in how clinicians view and treat IBD. Anti-tumor necrosis factor (TNF)-α strategies using infliximab and adalimumab currently dominate the therapeutic arena. Better understanding of how these biologicals work is driving the quest for loftier therapeutic goals of achieving mucosal healing, sustaining deep remission, and even modifying the natural history of IBD. However, not all patients respond to anti-TNF drugs. Immune-mediated adverse reactions and loss of efficacy with time also limit their use. There are many investigational drugs undergoing active clinical trials. Many have not fulfilled their early promises but some are potentially making the transition from bench to trial and to the bedside in the near future. Clinicians and investigators need to underpin our excitement with caution for the unknown long-term consequences of modulating cytokines and selective adhesion molecules in human. Here we provide an overview of investigational new drugs and other therapeutic strategies currently undergoing clinical trials in IBD.

Trial Protocol: Communicating DNA-based risk assessments for Crohn's disease: a randomised controlled trial assessing impact upon stopping smoking

BACKGROUND

Estimates of the risk of developing Crohn's disease (CD) can be made using DNA testing for mutations in the NOD2 (CARD15) gene, family history, and smoking status. Smoking doubles the risk of CD, a risk that is reduced by stopping. CD therefore serves as a timely and novel paradigm within which to assess the utility of predictive genetic testing to motivate behaviour change to reduce the risk of disease. The aim of the study is to describe the impact upon stopping smoking of communicating a risk of developing CD that incorporates DNA analysis. We will test the following main hypothesis:Smokers who are first degree relatives (FDRs) of CD probands are more likely to make smoking cessation attempts following communication of risk estimates of developing CD that incorporate DNA analysis, compared with an equivalent communication that does not incorporate DNA analysis.

METHODS/DESIGN

A parallel groups randomised controlled trial in which smokers who are FDRs of probands with CD are randomly allocated in families to undergo one of two types of assessment of risk for developing CD based on either: i. DNA analysis, family history of CD and smoking status, or ii. Family history of CD and smoking status. The primary outcome is stopping smoking for 24 hours or longer in the six months following provision of risk information. The secondary outcomes are seven-day smoking abstinence at one week and six month follow-ups. Randomisation of 470 smoking FDRs of CD probands, with 400 followed up (85%), provides 80% power to detect a difference in the primary outcome of 14% between randomised arms, at the 5% significance level.

DISCUSSION

This trial provides one of the strongest tests to date of the impact of communicating DNA-based risk assessment on risk-reducing behaviour change. Specific issues regarding the choice of trial design are discussed.

The TNF-α -308 polymorphism may affect the severity of Crohn's disease

OBJECTIVE

The goal of this project was to analyze the association between Crohn's disease, its clinical features, and the tumor necrosis factor alpha (TNF-α) -308 polymorphism.

METHODS

This is a case-control and cross-sectional study that enrolled 91 patients with Crohn's disease and 91 controls. Patients with Crohn's disease were characterized according to the Montreal Classification, along with their clinical and surgical treatment history. Analysis of the TNF-α -308 polymorphism was performed using a commercial kit. A stratified analysis was applied using an OR (odds ratio) with a 95% confidence interval. The chi-square and Fisher's exact tests were utilized for analysis of the association between the polymorphism and the clinical features of Crohn's disease.

RESULTS

The low producer predicted phenotype was present in 76.9% of Crohn's disease cases and 75.8% of controls (OR 0.94 [0.45-1.97]). The TNF2 allele and the high producer predicted phenotype were more frequent among patients with Crohn's disease penetrating behavior (p = 0.004). The TNF2 allele and the high producer predicted phenotype were also associated with a history of colectomy (p = 0.02), and the TNF2 allele was associated with small bowel resection (p = 0.03).

CONCLUSIONS

The TNF-α -308 polymorphism appears to affect the severity of the disease. However, TNF-α -308 polymorphism does not appear to be important for the susceptibility in the development of Crohn's disease.

An association between dietary arachidonic acid, measured in adipose tissue, and ulcerative colitis

BACKGROUND & AIMS

Dietary arachidonic acid, an n-6 polyunsaturated fatty acid (n-6 PUFA), might be involved in the etiology of ulcerative colitis (UC). We performed a prospective cohort study to determine whether high levels of arachidonic acid in adipose tissue samples (which reflects dietary intake) are associated with UC.

METHODS

We analyzed data collected from 57,053 men and women in the EPIC-Denmark Prospective Cohort Study from 1993 to 1997. Adipose tissue biopsy samples were collected from gluteal regions at the beginning of the study, the cohort was monitored over subsequent years, and participants who developed UC were identified. A subcohort of 2510 randomly selected participants were used as controls. Concentrations of arachidonic acid were measured in adipose tissue samples. In the analysis, arachidonic acid levels were divided into quartiles; relative risks (RR) were calculated and adjusted for smoking, use of aspirin and nonsteroidal anti-inflammatory drugs, and levels of n-3 PUFAs.

RESULTS

A total of 34 subjects (56% men) developed incident UC at a median age of 58.8 years (range, 50.0-69.0 years). Those in the highest quartile for arachidonic acid concentrations in adipose tissue had an RR for UC of 4.16 (95% confidence interval [CI]: 1.56-11.04); a trend per 0.1% increase in arachidonic acid of 1.77 in RR was observed (95% CI: 1.38-2.27). The fraction attributed the highest levels of arachidonic acid was 40.3%.

CONCLUSIONS

Individuals with the highest relative concentrations of arachidonic acid in adipose tissue have a significantly greater risk of developing UC. Dietary modifications might therefore prevent UC or reduce disease symptoms.

Incidence, prevalence, and time trends of pediatric inflammatory bowel disease in Northern California, 1996 to 2006

OBJECTIVE

To examine the incidence and prevalence of pediatric inflammatory bowel disease (IBD) during 1996-2006 in a community-based health-care delivery system.

STUDY DESIGN

Members of Kaiser Permanente Northern California aged 0 to 17 years with IBD were identified by use of computerized medical information with confirmation obtained through review of the medical record.

RESULTS

The average annual incidence of IBD per 100000 was 2.7 (95% confidence interval [CI], 2.3-3.1) for Crohn's disease (CD) and 3.2 (CI, 2.8-3.6) for ulcerative colitis (UC). During the 11-year study period, the annual incidence per 100000 increased from 2.2 to 4.3 for CD (P = .09) and from 1.8 to 4.9 for UC (P < .001). The ratio of incident CD cases to incident UC cases was 0.9 in non-Hispanic whites, 1.6 in African Americans (P = .12), 0.3 in Hispanics (P < .001) and 0.4 in Asians (P = .04). The average length of enrollment during the 11-year study period exceeded 8 years. The point prevalence on December 31, 2006, per 100000 was 12.0 for CD (CI, 9.6-14.4) and 19.5 (CI, 16.5-22.6) for UC.

CONCLUSIONS

In this population the incidence of UC increased significantly by 2.7-fold and CD increased 2.0-fold without reaching statistical significance. Hispanic and Asian children had development of UC more often than CD, suggesting possible etiologic differences across racial and ethnic groups.

Hyperplastic polyposis syndrome is associated with cigarette smoking, which may be a modifiable risk factor

OBJECTIVES

Hyperplastic polyposis syndrome (HPS) confers an increased risk of colorectal cancer and is difficult to manage clinically. Because both polyps and resultant cancers display the CpG island methylator phenotype and mutation of the BRAF oncogene, and because sporadic cancers with these characteristics are associated with cigarette smoking, we hypothesized that cigarette smoking may predispose to the development of HPS.

METHODS

This was a case-control study with two independent control series conducted at a tertiary hospital in Brisbane, Queensland, Australia. Cases comprised patients with HPS (n=32) recruited through the database of the Queensland Familial Bowel Registry, who satisfied the World Health Organization international classification for HPS. Cases were compared with colonoscopy controls (n=298) defined as consecutive patients undergoing colonoscopy for clinical indications, who were free from polyps. We also compared cases with a second set of population controls (n=645) selected at random from a population register serving the catchment area for cases. This was an observational study, and all participants completed a questionnaire to obtain a comprehensive smoking history.

RESULTS

The prevalence rate of current smoking was 47% in HPS patients, 17% in colonoscopy controls, and 12% in population controls. HPS patients were significantly more likely to be current smokers than were either colonoscopy controls (odds ratio (OR)=8.3, 95% confidence interval (CI): 3.0-22.9) or population controls (OR=12.7, 95% CI: 4.9-33.1).

CONCLUSIONS

Cigarette smoking is strongly associated with HPS, thus suggesting that smoking exposure may increase the expression of this condition. Further studies should examine the possible benefits of quitting smoking in HPS patients.

Smoking and atherosclerotic cardiovascular disease: Part I: atherosclerotic disease process

The normal endothelium inhibits platelet and leukocyte adhesion to the vascular surface maintaining a balance of profibrinolytic and prothrombotic activity. Endothelial function is assessed largely as endothelium-dependent vasomotion, partly based on the assumption that impaired endothelium-dependent vasodilation reflects the alteration of important endothelial functions. Atherosclerotic risk factors, such as hypercholesterolemia, hypertension, diabetes and smoking, are associated with endothelial dysfunction. In the diseased endothelium, the balance between pro- and antithrombotic, pro- and anti-inflammatory, pro- and antiadhesive or pro- and antioxidant effects shifts towards a proinflammatory, prothrombotic, pro-oxidative and proadhesive phenotype of the endothelium. A common mechanism underlying endothelial dysfunction is related to the increased vascular production of reactive oxygen species. Recent studies suggest that inflammation per se, and C-reactive protein in particular, may contribute directly to endothelial dysfunction. The loss of endothelial integrity is a hallmark of atherosclerosis and the causal possible link between each individual risk factor, the development of atherosclerosis and the subsequent clinical events, such as myocardial infarction or stroke.

Active and passive smoking behaviour and cessation plans of patients with Crohn's disease and ulcerative colitis

BACKGROUND

Smoking is a remarkable risk factor in inflammatory bowel disease (IBD), with negative effects on Crohn's disease (CD) and positive effects on ulcerative colitis (UC). This makes different changes in smoking behaviour after diagnosis between CD and UC likely. Changes in active smoking, cessation plans and passive smoking were studied in IBD patients.

METHODS

820 IBD patients were sent a questionnaire on active and passive smoking, and cessation plans. A total of 675 (82%) patients (380 CD and 295 UC) responded.

RESULTS

More ever smoking UC patients stopped smoking before diagnosis than CD patients (63% vs 22%; p<0.001), resulting in 30% former smokers at diagnosis in UC and 13% in CD (p<0.001). The smoking cessation rates at and after diagnosis are equal between CD and UC. Half of the CD patients stopped smoking after diagnosis leading to less present smokers in CD than in a control population (26% (95% confidence interval: 21.1%-29.9%) vs 33%). For both CD (22% vs 35%; p=0.044) and UC (24% vs 53%; p=0.024) continuing smokers after diagnosis were less often higher educated than quitters. Cessation plans (89%), passive smoking in childhood and present passive smoking were not different between CD and UC patients.

CONCLUSION

There are no differences in changes in smoking behaviour at and after diagnosis between CD and UC patients, suggesting a lack of knowledge in these patients about the link between their disease and smoking behaviour. However, CD patients seem less refractory to smoking cessation than the general population. Therefore it is worthwhile putting energy in helping CD patients stop smoking.

Anti-inflammatory efficiency of levobupivacaine in an experimental colitis model

AIM: To investigate the efficiency of levobupivacaine in treating experimentally induced colitis in rats.

METHODS: Colitis was induced by trinitrobenzene sulfonic acid and ethanol in 30 rats under general anesthesia, and 10 rats were used as a sham group. Subsequent to induction of colitis, rats were divided into three groups; budesonide group received 0.1 mg/kg budesonide, levobupivacaine group received 10 mg/kg levobupivacaine and saline group received 1 mL saline solution via rectal route for 7 d. In the sham group, only routine rectal catheterization was performed without use of any material. At the end of 7 d, laparotomy and total colectomy were performed for histopathological examination in all rats and blood samples were drawn for measurement of tumor necrosis factor (TNF)-α and interleukin (IL)-6 following cardiac puncture. Macroscopic and microscopic evaluations of the specimens were performed by a pathologist blinded to group assignment of the rats.

RESULTS: Weight loss (P = 0.016) and macroscopic examination scores (P = 0.001) were significantly higher in saline group than others. Histopathological scoring was comparable between all colitis groups (P = 0.350). There was no significant difference in TNF-α levels and IL-6 levels (P = 0.150).

CONCLUSION: The significant improvement in macroscopic scores suggests that levobupivacaine may have topical anti-inflammatory effects in an experimental colitis model; however, this finding was not supported by microscopic findings.

Differences in genetic background between active smokers, passive smokers, and non-smokers with Crohn's disease

OBJECTIVES

Smoking behavior and genetic variations are important factors for the development of Crohn's disease (CD), but studies investigating the interaction between smoking and genetic background are scarce. We studied allelic associations of 19 confirmed variants located in 14 CD-associated genes or loci, in CD patients stratified for active smoking at diagnosis and passive smoking in childhood.

METHODS

Genotyping data of 19 CD-associated single-nucleotide polymorphisms (SNPs) were available for 310 CD patients and 976 controls. Data on active smoking at diagnosis and passive smoking in childhood were obtained through a written questionnaire and a review of medical charts.

RESULTS

The loci associated in smoking, but not in non-smoking, CD patients were 5p13.1 (rs17234657), DLG5 (rs2165047), NKX2-3 (rs10883365), and NOD2 (R702W). The loci associated in non-smoking, but not in smoking, CD patients were IL23R (rs7517847), 5p13.1 (rs9292777), IRGM (rs13361189 and rs4958847), IL12B (rs6887695), and CCNY (rs3936503). PTPN2 (rs2542151) was only associated in the smoking CD cohort (P=0.041), and not in the entire cohort (P=0.23) or in the non-smoking CD cohort (P=0.80). In passively smoking CD patients, associations with 13 SNPs in 9 loci were found, including PTPN2. In non-passive smoking CD patients, only associations with NOD2 (1007fsinsC and G908R) were found.

CONCLUSIONS

The difference in associated genes between smoking and non-smoking CD patients implies a complex gene-environment interaction. Therefore, genetic studies of CD should be stratified for smoking behavior, as otherwise moderately associated genes such as PTPN2 can be missed.

Ulcerative colitis in a Southern European country: a national perspective

BACKGROUND

The incidence, prevalence, and even the clinical behavior of ulcerative colitis (UC) are highly variable in different world regions. In previous studies, Portugal was reported as having a milder clinical behavior. The aim of this study was to apply the Montreal Classification in a large group of UC Portuguese patients in order to describe their clinical characteristics and evaluate variables potentially useful for outcome prediction.

METHODS

A cross-sectional study based on data collected from a nationwide online registry was undertaken.

RESULTS

In all, 2863 patients with UC were included. Twenty-one percent had ulcerative proctitis, 52% left-sided colitis, and 28% extensive colitis. Sixty percent of patients had taken steroids, 14% immunosuppressors, 1% biologicals, and 4.5% were submitted to surgery. Patients with extensive colitis had more severe activity, needing more steroids, immunosuppressors, and surgery. At the time of diagnosis 61% were less than 40 years old and 5% less than 16. Younger patients also had a more aggressive initial course. Thirty-eight percent of patients had only taken salicylates during the disease course and were characterized by a lower incidence of systemic symptoms at presentation (3.8% versus 8.8%, P < 0.001), fewer extraintestinal manifestations (7.7% versus 24.0%, P < 0.001), and a higher prevalence of proctitis (32.1% versus 10.0%).

CONCLUSIONS

A more aggressive phenotype was found in extensive colitis and in the initial course of younger patients, with an increased need for steroids and immunosuppressors. In addition, a significant percentage of patients, particularly with proctitis, showed a milder clinical evolution and were maintained in remission only with salicylates.

Inflammatory bowel disease

Inflammatory bowel diseases (IBDs) encompass ulcerative colitis, Crohn's disease, and indeterminate colitis, all of which are characterized by remission and exacerbation of gastrointestinal symptoms, and a variety of extraintestinal manifestations including those affecting the oral cavity. Although not particularly a cause for mortality, inflammatory bowel diseases are associated with significant morbidity and impact on the quality of life. This article reviews clinical presentation, diagnostic criteria, and therapeutic modalities for the 2 main types of inflammatory bowel disease and discusses manifestations of these conditions in the oral cavity. The role of the oral health care provider in timely recognition and referral for medical work-up as well as management of oral complaints is also emphasized.

Predictors of disease severity in ulcerative colitis patients from Southwestern Ontario

AIM: To understand the demographic characteristics of patients in Southwestern Ontario, Canada with ulcerative colitis (UC) in order to predict disease severity.

METHODS: Records from 1996 to 2001 were examined to create a database of UC patients seen in the London Health Sciences Centre South Street Hospital Inflammatory Bowel Disease Clinic. To be included, patients’ charts were required to have information of their disease presentation and a minimum of 5 years of follow-up. Charts were reviewed using standardized data collection forms. Disease severity was generated during the chart review process, and non-endoscopic Mayo Score criteria were collected into a composite.

RESULTS: One hundred and two consecutive patients’ data were entered into the database. Demographic analyses revealed that 51% of the patients were male, the mean age at diagnosis was 39 years, 13.7% had a first degree relative with inflammatory bowel disease (IBD), 61.8% were nonsmokers and 24.5% were ex-smokers. In 22.5% of patients the disease was limited to the rectum, in 21.6% disease was limited to the sigmoid colon, in 22.5% disease was limited to the left colon, and 32.4% of patients had pancolitis. Standard multiple regression analysis which regressed a composite of physician global assessment of disease severity, average number of bowel movements, and average amount of blood in bowel movements on year of diagnosis and age at time of diagnosis was significant, R² = 0.306, F (7, 74) = 4.66, P < 0.01. Delay from symptoms to diagnosis of UC, gender, family history of IBD, smoking status and disease severity at the time of diagnosis didnot significantly predict the composite measure.

CONCLUSION: UC severity is associated with younger age at diagnosis and year of diagnosis in a longitudinal cohort of UC patients, and may identify prognostic UC indicators.

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.

Nicotine enemas for active Crohn's colitis: an open pilot study

Background. Smoking has a detrimental effect in Crohn's disease (CD), but this may be due to factors in smoking other than nicotine. Given that transdermal nicotine benefits ulcerative colitis (UC), and there is a considerable overlap in the treatment of UC and CD, the possible beneficial effect of nicotine has been examined in patients with Crohn's colitis. Aims. To assess the efficacy and safety of nicotine enemas in active Crohn's colitis. Patients. Thirteen patients with active rectosigmoid CD; 3 patients were excluded because they received antibiotics. Methods. Subjects were given 6 mg nicotine enemas, each day for 4 weeks, in an open pilot study. At the beginning and end of the trial, a Crohn's disease activity index (CDAI) score was calculated, sigmoidoscopy was performed, and haematological inflammatory markers measured. Results. Mean CDAI decreased from 202 to 153—the score was reduced in 6 patients, unchanged in 3, and increased in one. Frequency of bowel movements decreased in 8 patients and the sigmoidoscopy grade was reduced in 7. Mean C-reactive protein decreased from 22.0 to 12.3 mg/L. There were no withdrawals due to adverse events. Conclusions. In this relatively small study of patients with active Crohn's colitis, 6 mg nicotine enemas appeared to be of clinical benefit in most patients. They were well tolerated and safe.

Risk factors associated with rosacea

BACKGROUND

Although rosacea is a common disease, the cause of disease is still a mystery -Helicobacter pylori infection, genetic predisposition, climatic factors, and detrimental habits are implicated as triggers of rosacea.

OBJECTIVE

The aim of current study is to evaluate several suspected risk factors coincidently.

METHODS

Patients with rosacea from a dermatology clinic and skin-healthy controls from an randomly selected employees' population enrolled the study. Skin status were evaluated by one and same dermatologist. Participants were queried for age, gender, sun-reactive skin type, and detrimental habits using a questionnaire; blood samples for detecting Helicobacter pylori serostatus were collected.

RESULTS

Totally 145 skin-healthy controls and 172 subjects either with flushing episodes or established rosacea included the study. In multivariate analysis, rosacea patients had significantly higher chance to have photosensitive skin types (OR 1.75; 95% CI 1.01-3.04; P < 0.05), positive family history to rosacea (OR 4.31; 95% CI 2.34-7.92; P < 0.0001) or previous smoking status (OR 2.01; 95% CI 1.07-3.80; P < 0.05) comparing with skin-healthy controls. There were no statistically significant differences either in gender, Helicobacter pylori serostatus, caffeine intake, alcohol consumption, occupational environment, or education level between rosacea patients and controls.

CONCLUSION

Rosacea is foremost associated with familial predisposition. There is no association between Helicobacter pylori infection and rosacea in current study.

[Chronic inflammatory intestinal diseases. Pathophysiology and therapy]

The pathogenesis and therapy of chronic inflammatory intestinal diseases are characterized by an obvious discrepancy. There is extensive agreement that the pathogenesis is substantially based on a disruption of the barrier of the intestinal mucous membrane against luminal bacteria. This has been demonstrated in recent years by evidence from various disciplines, in particular from genetics, microbiology, morphology and innate immunology. However, there is also the evidence-based therapy which, as in the past, is aimed against the effectors of the adaptive immune system. In this case the therapy with biologicals is more aggressive and takes the risk of a series of undesired side-effects. This dichotomy of pathological knowledge and therapeutic innovation is not only medically unsatisfactory but also makes it difficult to present a consistent picture of these symptoms. Despite this an attempt will be made to bridge these inconsistencies and to demonstrate possible future developments which will lead to a final causal therapy. An extended version of this article appears in our newly published book "Colitis ulcerosa und Morbus Crohn".

Systematic review: the role of breastfeeding in the development of pediatric inflammatory bowel disease

OBJECTIVES

To assess the current evidence for the role of breastfeeding in the development of early onset inflammatory bowel disease (IBD) with a systematic review.

STUDY DESIGN

An electronic database search was performed (January 1966-January 2008) with keywords related to IBD and breastfeeding, looking specifically for studies that reported outcome in early-onset disease (<16 years of age) and "any exposure" to breast milk as the variables. Meta-analysis of studies included for review was then performed by using a random effects model, and results were expressed as odds ratios (OR) with 95% CIs.

RESULTS

A total of 79 articles were identified, 20 of which were found describing breastfeeding in relation to the development of IBD; 8 of these articles included separate early-onset groups. One study did not describe "any exposure" to breast milk for the early onset group, so 7 studies were included in the meta-analysis. Breast milk exposure had a significant protective effect (OR, 0.69; 95% CI, 0.51-0.94; P = .02) in developing early-onset IBD. A non-significant difference was demonstrated for ulcerative colitis and Crohn's disease individually (OR, 0.72; 95% CI, 0.51-1.02; P = .06; OR, 0.64; 95% CI, 0.38-1.07; P = .09, respectively).

CONCLUSIONS

The current evidence demonstrates a possible protective effect for breast milk in the development of early onset IBD. However, the quality of existing data is generally poor. These findings need to be investigated in well-designed prospective studies.

Phenotypic and genotypic characteristics of inflammatory bowel disease in French Canadians: comparison with a large North American repository

OBJECTIVES

Phenotype characteristics of inflammatory bowel disease (IBD) may differ significantly among ethnic subpopulations. The aim of this study was to characterize the IBD phenotype in French Canadians, the most prominent founder population in North America.

METHODS

Using well-characterized phenotype data in the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)-IBD Genetics Consortium repository on patients with IBD, we compared phenotypic characteristics of 202 French Canadians with those of 1,287 other Caucasian patients. These included diagnosis, anatomical location, disease behavior, extraintestinal manifestations, surgical history, and family history of IBD.

RESULTS

French-Canadian patients with Crohn's disease (CD) were less likely to have stricturing disease (11 vs. 21%, P=0.005; odds ratio (OR): 0.45, 95% confidence interval (95% CI): 0.24-0.85). Using a stringent definition of ethnicity (three out of four grandparents being French Canadians, as opposed to self-report, n=148), French Canadians had a tendency toward developing fistulizing CD (37 vs. 28%, P=0.07), and there was an increased prevalence of sacroiliitis among those with IBD (4 vs. 2%, P=0.045). Among French Canadians, the numbers of current smokers in CD (40 vs. 25%, P=0.006) and former smokers in ulcerative colitis (UC) (35 vs. 20%, P=0.03) were significantly higher. The prevalence of one of the three main variants of nucleotide-binding oligomerization domain containing 2 (NOD2) single-nucleotide polymorphisms (SNPs) among French-Canadian CD patients was 43.2%. The 3020insC SNP correlated with small bowel disease in French Canadians (25 [corrected] vs. 0%, P=0.006).

CONCLUSIONS

French Canadians show an IBD phenotype profile distinct from other Caucasian IBD populations, with an accentuated association between smoking status and IBD. This unique profile may have implications regarding the need for a different approach to the management of IBD in this population.

[Inflammatory bowel disease: genetic or environmental diseases?]

Pathophysiology of inflammatory bowel diseases depends on the interaction between genetic susceptibility and environmental factors leading to a deregulated immune intestinal response resulting in bowel lesions. Epidemiologic variations of inflammatory bowel diseases with time (incidence, prevalence) and space suggest a role for risk environmental factors, but so far only smoking habits and appendectomy have been identified as influencing the risk of occurrence and the course of the diseases. Studies of monozygotic and dizygotic twins and the existence of familial aggregation are strong evidence for an important, but not exclusive, role for genetic susceptibility. Since the discovery of NOD2/CARD15 mutations, numerous genes have been associated with inflammatory bowel diseases, some of them involved in the regulation of innate immunity and cellular clearance of infectious agents (autophagy). Thus, new hypothesis include a key role of mucosal human microbiota which could be partly influenced by environmental factors generated by modern life. The improvement of life hygiene, the change of food composition and habits, the industrial pollution in developed countries, may influence, directly or by the way of modifying intestinal human microbiota, inflammatory bowel diseases risk occurrence.

[Multifactorial etiology and pathogenic factors in inflammatory bowel disease]

All the currently available evidence suggests that the two types of inflammatory bowel disease (IBD), Crohn's disease (CD) and ulcerative colitis (UC), involve a conflict between the immune system of the intestinal mucosa and intraluminal antigens, mainly the intestinal microflora, which are normally tolerated by the immune system. This conflict is modulated by numerous environmental factors and a clear polygenetic predisposition. The present article reviews the behavior of all the etiologic circumstances (microbial, genetic and environmental) and subsequently analyzes the possible pathogenic factors in which the etiologies can be found, namely: dysfunction of the intestinal epithelium, innate immune system alterations, and distortion of the cellular and humoral arms of the acquired immune system. The role of tissue ischemia in CD and expression of "extraintestinal inflammatory metastases", both in CD and UC, are briefly discussed. Finally, the view that IBD may be a spectrum of pathological processes provoked by distinct etiopathogenic factors and the possible biological significance of the growing incidence of this disease in the western world, coinciding with the decline in infectious diseases in this geographical area, are discussed.

Maternal exposure to secondhand cigarette smoke primes the lung for induction of phosphodiesterase-4D5 isozyme and exacerbated Th2 responses: rolipram attenuates the airway hyperreactivity and muscarinic receptor expression but not lung inflammation and atopy

Airway hyperreactivity (AHR), lung inflammation, and atopy are clinical signs of allergic asthma. Gestational exposure to cigarette smoke (CS) markedly increases the risk for childhood allergic asthma. Muscarinic receptors regulate airway smooth muscle tone, and asthmatics exhibit increased AHR to muscarinic agonists. We have previously reported that in a murine model of bronchopulmonary aspergillosis, maternal exposure to mainstream CS increases AHR after acute intratracheal administration of Aspergillus fumigatus extract. However, the mechanism by which gestational CS induces allergic asthma is unclear. We now show for the first time that, compared with controls, mice exposed prenatally to secondhand CS exhibit increased lung inflammation (predominant infiltration by eosinophils and polymorphs), atopy, and airway resistance, and produce proinflammatory cytokines (IL-4, IL-5, IL-6, and IL-13, but not IL-2 or IFN-gamma). These changes, which occur only after an allergen (A. fumigatus extract) treatment, are correlated with marked up-regulated lung expression of M1, M2, and M3 muscarinic receptors and phosphodiesterase (PDE)4D5 isozyme. Interestingly, the PDE4-selective inhibitor rolipram attenuates the increase in AHR, muscarinic receptors, and PDE4D5, but fails to down-regulate lung inflammation, Th2 cytokines, or serum IgE levels. Thus, the fetus is extraordinarily sensitive to CS, inducing allergic asthma after postnatal exposure to allergens. Although the increased AHR might reflect increased PDE4D5 and muscarinic receptor expression, the mechanisms underlying atopy and lung inflammation are unrelated to the PDE4 activity. Thus, PDE4 inhibitors might ease AHR, but are unlikely to attenuate lung inflammation and atopy associated with childhood allergic asthma.

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.

Influence of smoking on colonic gene expression profile in Crohn's disease

Background

The development and course of Crohn's disease (CD) is related to both genetic and environmental factors. Smoking has been found to exacerbate the course of CD by increasing the risk of developing fistulas and strictures as well as the need for surgery, possibly because of an interaction between smoking or nicotine on macrophage function and the intestinal microvasculature. Several genes are involved in the pathogenesis of CD, and in this study the gene expression differences of the descending colonic mucosa were investigated in CD (smokers or never smokers) and controls (smokers or never smokers).

Aim

To identify any difference in gene expression of the descending colonic mucosa between smoking and never-smoking CD patients (and controls) by determining genetic expression profiles from microarray analysis.

Methods

Fifty-seven specimens were obtained by routine colonoscopy from the included material: CD smokers (n = 28) or never-smokers (n = 14) as compared to fifteen healthy controls (8 smokers and 7 never-smokers). RNA was isolated and gene expression assessed with Affymetrix GeneChip Human Genome U133 Plus 2.0. Data were analyzed by principal component analysis (PCA), Wilcoxon rank sum test and multiple linear regressions. Real-time (RT) PCR was subsequently applied to verify microarray results.

Results

The PCA analysis showed no intrinsic clustering of smokers versus never-smokers. However, when Wilcoxon rank sum test corrected with Q values were performed, six known genes were significantly expressed differently in the inflamed CD smokers as compared to the inflamed CD never-smokers: ring finger protein 138 (RNF138), metalothionein 2A (MT2A) and six transmembrane epithelial antigen of the prostate 3 (STEAP3), SA hypertension-associated homolog, PGM2L1 and KCNJ2. The subsequent RT-PCR-analyses verified, however, that only RNF138, MT2A and STEAP3 were significantly up-regulated in CD smokers in specimens with inflammatory activity of the descending colon.

Conclusions

The present study demonstrates that the genes, RNF138, MT2A, and STEAP3 are differently expressed in the inflamed descending colon of smoking versus never-smoking CD patients, which might be of relevance for the poorer clinical course among CD smokers. Many gastroenterologists are still not totally aware of the benefits of smoking cessation in relation to CD, and do not put much effort into getting the patients to quit, therefore more information on the negative effects of smoking, seems warranted.