Appendectomy, smoking habits and the risk of developing ulcerative colitis: a case control study in private practice setting

Ethnic Differences in the Smoking-related Risk of Inflammatory Bowel Disease: A Systematic Review and Meta-analysis

BACKGROUND AND AIMS

The association between smoking and inflammatory bowel disease [IBD] relies on old meta-analyses including exclusively non-Jewish White populations. Uncertainty persists regarding the role of smoking in other ethnicities.

METHODS

We systematically searched Medline/PubMed, Embase, and Scopus for studies examining tobacco smoking and the risk of developing IBD, ie, Crohn's disease [CD] or ulcerative colitis [UC]. Two authors independently extracted study data and assessed each study's risk of bias. We examined heterogeneity and small-study effect, and calculated summary estimates using random-effects models. Stratified analyses and meta-regression were employed to study the association between study-level characteristics and effect estimates. The strength of epidemiological evidence was assessed through prespecified criteria.

RESULTS

We synthesised 57 studies examining the smoking-related risk of developing CD and UC. Non-Jewish White smokers were at increased risk of CD (29 studies; relative risk [RR]: 1.95, 95% confidence interval [CI]: 1.69‒2.24; moderate evidence). No association was observed in Asian, Jewish. and Latin-American populations [11 studies; RR: 0.97; 95% CI: 0.83-1.13], with no evidence of heterogeneity across these ethnicities. Smokers were at reduced risk of UC [51 studies; RR: 0.55, 95% CI: 0.48-0.64; weak evidence] irrespectively of ethnicity; however, cohort studies, large studies, and those recently published showed attenuated associations.

CONCLUSIONS

This meta-analysis did not identify any increased risk of CD in smokers in ethnicities other than non-Jewish Whites, and confirmed the protective effect of smoking on UC occurrence. Future research should characterise the genetic background of CD patients across different ethnicities to improve our understanding of the role of smoking in CD pathogenesis.

Epidemiological and clinical aspects of ulcerative colitis in west of Iran: a cross sectional study

Introduction

One of the forms of inflammatory bowel disease (IBD) that causes inflammation and ulcers in colon is ulcerative colitis (UC). This study was aimed to determine the epidemiological and clinical aspects of patients with ulcerative colitis in the west of Iran.

Methods

In this cross sectional study, we evaluated 150 patients with definite diagnosis of UC who referred to a subspecialty gastroenterology clinic in Khorramabad, Iran. The study was performed from May 2014 to August 2015 by using census method. Demographic characteristics as well as patients’ clinical profiles were extracted using a checklist. Disease severity was determined by the Truelove and Witt’s classification of ulcerative colitis (UC). Data were analyzed using SPSS software, version 17 for windows (IBM Inc., NY, US).

Results

A total of 150 patients with definite diagnosis of UC were analyzed, including 84 (56 %) women and 66 (44 %) men (male/female ratio = 1.27). The mean age of patients was 33.7 ± 12.5 years with an age range of 17–98 years. The age of the majority of patients was 20–29 and most of them (56 %) were women and living in urban areas (70.7 %). The most common site of the involvement in colon was rectosigmoid (66 patients, 44 %). Severity of the disease was mild in 36 patients (24.1 %), moderate and severe in 74 and 40 patients (49.3 and 26.6 %), respectively. The most common clinical manifestation of the patients was dysentery (68 %) and then rectorrhagia (60 %). Only 12 of all patients (7.8 %) mentioned a positive family history of IBD in their first degree kinfolks. Ten patients (6.7 %) had a history of regular smoking and four of them (2.6 %) mentioned a history of appendectomy. Four patients (5.3 %) had a positive history of smoking by their mothers during their pregnancy.

Conclusion

The results of this study demonstrate differences and similarities in demographic and clinical characteristics of UC in this part of Iran in comparison to other parts of the country.

Influence of environmental factors in the development of inflammatory bowel diseases

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

The Link between the Appendix and Ulcerative Colitis: Clinical Relevance and Potential Immunological Mechanisms

The human appendix has long been considered as a vestigial organ, an organ that has lost its function during evolution. In recent years, however, reports have emerged that link the appendix to numerous immunological functions in humans. Evidence has been presented for an important role of the appendix in maintaining intestinal health. This theory suggests that the appendix may be a reservoir or 'safe house' from which the commensal gut flora can rapidly be reestablished if it is eradicated from the colon. However, the appendix may also have a role in the development of inflammatory bowel disease (IBD). Several large epidemiological cohort studies have demonstrated the preventive effect of appendectomy on the development of ulcerative colitis, a finding that has been confirmed in murine colitis models. In addition, current studies are examining the possible therapeutic effect of an appendectomy to modulate disease course in patients with ulcerative colitis. This literature review assesses the current knowledge about the clinical and immunological aspects of the vermiform appendix in IBD and suggests that the idea of the appendix as a vestigial remnant should be discarded.

Exposome in IBD: recent insights in environmental factors that influence the onset and course of IBD

It is generally agreed that environmental factors trigger the onset and cause flares of inflammatory bowel disease. Although we have learned much about genetic susceptibility factors of inflammatory bowel disease in recent years, our knowledge on these environmental factors is limited. The sum of all environmental factors a human is exposed to during lifetime has been termed the exposome. The challenge of investigating the exposome is discussed in this overview. The environmental exposure of a subject causes changes in the intestinal microbiota and subsequently changes the epigenetic imprinting of the mucosa and the associated immune system. Some relevant environmental factors have been investigated in recent years in inflammatory bowel disease and other (auto)inflammatory disease. These factors can be categorized in air pollution, diet, drugs, stress, infections, water pollution, food additives, and lifestyle. Examples from those categories and their potential pathophysiological mechanism are discussed.

Increased risk of pulmonary tuberculosis among patients with appendectomy in Taiwan

The aim of this study was to determine whether there is a relationship between appendectomy and pulmonary tuberculosis in Taiwan. We designed a case-control study by analyzing the database from the Taiwan National Health Insurance Program. In total, we found 11,366 individuals (aged 20 years and older) with newly diagnosed pulmonary tuberculosis as the case group and 45,464 individuals without pulmonary tuberculosis as the control group from 1998 to 2011. The case group and the control group were matched on sex, age, and index year of diagnosing pulmonary tuberculosis. Using the multivariable unconditional logistic regression model, we measured the odds ratio (OR) and 95 % confidence interval (CI) for the risk of pulmonary tuberculosis associated with appendectomy and other comorbidities. After controlling for covariables, the multivariable unconditional logistic regression model disclosed that the OR of pulmonary tuberculosis was 1.4 in appendectomized patients (95 % CI = 1.13, 1.75) when compared to individuals without appendectomy. In further analysis, comorbidity with chronic obstructive pulmonary diseases (OR = 4.63, 95 % CI = 3.21, 6.68), pneumoconiosis (OR = 7.80, 95 % CI = 1.43, 42.5), chronic kidney diseases (OR = 5.65, 95 % CI = 1.79, 17.8), or diabetes mellitus (OR = 2.11, 95 % CI = 1.30, 3.44) increased the risk of pulmonary tuberculosis in appendectomized patients. Individuals with appendectomy are at a 1.4-fold increased risk of pulmonary tuberculosis. Comorbidities, including chronic obstructive pulmonary disease, pneumoconiosis, chronic kidney diseases, and diabetes mellitus, enhance the risk of pulmonary tuberculosis.

Perfil dos pacientes ambulatoriais com doenças inflamatórias intestinais

INTRODUÇÃO: As doenças inflamatórias intestinais são enfermidades crônicas, que afetam significativamente a qualidade e expectativa de vida dos pacientes. Existe polimorfismo clínico e a abordagem terapêutica tem sido modificada nos últimos anos. OBJETIVO: Reavaliar o perfil dos pacientes em acompanhamento ambulatorial analisando o comportamento das doenças, sua prevalência e conduta terapêutica. MÉTODOS: Foi realizado um estudo transversal da última atualização da base de dados dos pacientes de ambulatório de doença inflamatória intestinal em 2010. Os itens analisados foram sexo e idade dos pacientes, tipo da doença (retocolite ulcerativa ou doença de Crohn), localização da doença, tipo de medicação em uso, e se os pacientes estavam sintomáticos ou assintomáticos na última consulta. RESULTADOS: Foram estudados 171 pacientes. O sexo feminino mostrou-se predominante (60,8%) e a média de idade dos pacientes foi de 42,3, variando de 16 a 84 anos. Em relação ao tipo de doença inflamatória, a retocolite ulcerativa mostrou-se mais prevalente (58,5%). As localizações mais frequentes na retocolite ulcerativa foram pancolite e retite, ambas com 26% (n=26). Na doença de Crohn a localização ileocolônica foi a mais prevalente, com 47,9% (n=34), sendo seguida pela colônica com 25,4% (n=18). A monoterapia foi a mais utilizada, correspondendo a 54,4% dos pacientes, sendo que os imunossupressores foram as drogas de uso mais frequente (35,5%). A associação de medicamentos foi necessária em 36,3% dos casos, sendo a combinação mais frequente salicilato local com sistêmico em 33,9%. Nos portadores de retocolite ulcerativa 82% estavam em uso de salicilatos, seja local ou sistêmico. Na doença de Crohn 57,7% faziam uso de imunossupressores. Em relação à atividade da doença na última consulta, 71,3% dos pacientes apresentavam-se assintomáticos. CONCLUSÃO: A retocolite ulcerativa foi pouco mais prevalente que a doença de Crohn, sendo pancolite e retite as localizações mais frequentes. Na doença de Crohn a localização ileocolônica foi a mais encontrada seguida pela colônica. A monoterapia com imunossupressores foi o esquema terapêutico mais utilizado. A maioria dos pacientes apresentava-se assintomático na última consulta.

The role of heme oxygenase and carbon monoxide in inflammatory bowel disease

Inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn's disease, is a chronic and recurrent inflammatory disorder of the intestinal tract. Since the precise pathogenesis of IBD remains unclear, it is important to investigate the pathogenesis of IBD and to evaluate new anti-inflammatory strategies. Recent evidence suggests that heme oxygenase-1 (HO-1) plays a critical protective role during the development of intestinal inflammation. In fact, it has been demonstrated that the activation of HO-1 may act as an endogenous defensive mechanism to reduce inflammation and tissue injury in various animal intestinal injury models induced by ischemia-reperfusion, indomethacin, lipopolysaccharide-associated sepsis, trinitrobenzene sulfonic acid or dextran sulfate sodium. In addition, carbon monoxide (CO) derived from HO-1 has been shown to be involved in the regulation of intestinal inflammation. Furthermore, administration of a low concentration of exogenous CO has a protective effect against intestinal inflammation. These data suggest that HO-1 and CO may be novel therapeutic molecules for patients with gastrointestinal inflammatory diseases. In this review, we present what is currently known regarding the role of HO-1 and CO in intestinal inflammation.

Clinical course of ulcerative colitis

To provide a review of studies on prognosis in ulcerative colitis by reviewing the relevant population-based cohort studies. On the basis of incidence and population studies, ulcerative colitis has a favourable clinical course, with good quality of life, a chronic course characterized by at least one relapse, and a surgery rate of 30% after 10 years from diagnosis. Patients affected by severe ulcerative colitis have a higher risk of colectomy, and some clinical variables may predict the disease's clinical course. Most patients respond to steroids and only a low percentage become dependent, or non-responders to steroids. Patients who have a long-lasting ulcerative colitis (>10 years) or are affected by an extensive disease have an increased risk of developing colorectal cancer, while those treated with immunosuppressants for long period of time may have an increased risk of developing lymphomas. Data on mortality in ulcerative colitis patients are not homogeneous, but if a real risk exists it is in patients with extensive or severe disease. The evidence that patients with severe ulcerative colitis are often non-smokers may explain why in one study the mortality rate was lower.