Phenotypic concordance in familial inflammatory bowel disease (IBD). Results of a nationwide IBD Spanish database

Genes vs environment in inflammatory bowel disease: an update

INTRODUCTION

Inflammatory bowel diseases (IBDs) are known to be caused by a combination of genetic and environmental factors that vary in their influence on the development of the disease. Environmental exposures seem to influence IBD susceptibility, whereas genetic background is thought to modulate the impact of the environment on disease course and phenotype.

AREAS COVERED

A broad review of the involvement of genes and the environment in IBD pathogenesis was performed, and information regarding the main genetic and environmental factors - categorized into lifestyle factors, drugs, diet, and microbes - was updated. Monogenic very early onset IBD (VEO-IBD) was also discussed.

EXPERT OPINION

In the upcoming years, better understanding of gene-environment interactions will contribute to the possibility of a better prediction of disease course, response to therapy, and therapy-related adverse events with the final goal of personalized and more efficient patient management.

Clinical Phenotype and Disease Course of Inflammatory Bowel Disease: A Comparison Between Sporadic and Familial Cases

BACKGROUND

The role of genetic and environmental factors in inflammatory bowel disease's (IBD) clinical course is not fully clear. We aimed to assess the clinical phenotype, disease course, and prognosis of familial IBD in comparison with sporadic cases.

METHODS

We conducted a prospective national matched case-control study of registered IBD patients in the Iranian Registry of Crohn's and Colitis (IRCC) recruited from 2017 until 2020. Sporadic and familial IBD patients were matched based on age, sex, and disease duration. Data on demographics, past medical disease, family history of IBD, disease type, clinical phenotype, extraintestinal manifestations, IBD medications, IBD activity using the IBD-control-8 questionnaire and the Manitoba IBD index, emergency visits in the past 12 months, admissions in the past 3 months, history of colon cancer, IBD-related surgeries, and aggressive phenotype were gathered. Variable distributions were compared between sporadic and familial cases.

RESULTS

Overall, 5231 patients with ulcerative colitis (UC, 18.3% familial) and 1438 patients with Crohn's disease (CD, 16.7% familial) were registered in the IRCC. Age at diagnosis was similar between familial and sporadic cases. After matching, 3523 UC patients and 908 CD patients were enrolled in the study. Extraintestinal manifestations, UC extent, CD location and behavior, anti-TNF use, disease activity, colon cancer, IBD-related surgeries and the aggressive phenotype were similar between these sporadic and familial cases.

CONCLUSIONS

The prevalence of familial UC and CD cases in Iran was more similar to western countries, and family history did not show a predictive value for disease phenotype, course, and outcomes in our study.

Clinical and Demographic Profile of Inflammatory Bowel Disease Patients in a Reference Center of São Paulo, Brazil

Background

Crohn's disease (CD) and ulcerative colitis (UC) are chronic inflammatory diseases of the gastrointestinal tract with an increasing incidence in developing countries.

Purpose

To report clinical and demographic data of CD and UC at a referral center for inflammatory bowel disease (IBD) in São Paulo.

Patients and Methods

We conducted a retrospective cross-sectional study on adult patients with established IBD. Demographic and clinical data were obtained by medical records analysis from the IBD Outpatient Clinic of EPM-UNIFESP, from October 1997 to October 2017.

Results

Of 658 patients included, 355 had UC (54%) and 303 had CD (46%). UC was more prevalent in women than CD (219 [61.7%] vs 152 [50.2%], p=0.003). The median time between the onset of symptoms and diagnosis was 13 (5-38) months, with a longer duration for CD patients. CD mostly affected the ileocolonic location (47.9%). CD patients with stricture, fistula and/or perianal disease (213/303, 70.3%) were younger at diagnosis, had a longer disease duration, higher rates of corticosteroid, immunomodulatory, and biological therapy, hospitalization, and referral to surgery, compared to patients without complication. Extensive colitis was the most common extension of UC (50.6%), which was more frequently associated with younger age at diagnosis, hepatobiliary disease, increased need for hospitalization, higher use of immunomodulatory, and biologic therapy, compared to patients with less extensive disease. In the last 5 years, CD patients were more frequently on biologic and/or immunomodulatory (70.9%) therapy, and UC patients often received salicylates (78.1%) and immunomodulatory (28.1%) treatments. There was a consistent reduction in salicylate usage for CD in the last 5 years compared to the total period of follow-up.

Conclusion

Despite the increasing incidence, we highlight the diagnostic delay and a more complicated CD and extensive UC in this cohort, reflecting a high need for immunomodulatory and biological treatment, hospitalization, and surgery.

Conjugal inflammatory bowel disease: a systematic review and European survey

Background

The frequency of inflammatory bowel disease (IBD) is increased after marriage to an individual with the disease. Importantly, the offspring of these couples have a significant risk for developing the disease. Herein, we aimed to better characterize conjugal IBD.

Methods

A systematic literature search was conducted with predetermined search criteria. Relevant manuscripts reporting on couples with IBD and their offspring were selected. Concomitantly, a cross-sectional survey was conducted of couples where both members were affected with IBD, as well as their offspring, and electronically distributed by patients’ associations.

Results

We identified 20 reports of IBD in couples, for a total of 68 couples. Of these, 66% were concordant regarding IBD type and 66% were diagnosed after cohabitation. The overall prevalence of IBD in the offspring of these couples was 29%. Our survey identified 58 couples with IBD, with 62% being concordant regarding IBD type; 42.9% were diagnosed prior to cohabitation, in 12.5% one spouse was diagnosed before and the other after cohabitation, and in 44.6% the onset of disease occurred after cohabitation for both. The prevalence of IBD in children born from these couples was 10%. The probability of developing disease in the progeny was 2% at 10 years, 12% at 15 years, and 16% at 20 years of age.

Conclusions

IBD in couples occurs mostly after marriage to an individual with disease or after many years of cohabitation. In a modern cohort, the risk for the progeny was around 16% by the age of 20, lower than previously reported.

Concordance regarding disease type and phenotypic characteristics among patients with familial inflammatory bowel disease

BACKGROUND AND AIMS

The phenotypic concordance among familial cases of inflammatory bowel disease (IBD) has been rarely reported. Thus, the present study aimed to evaluate the concordance regarding disease type and phenotypic features in a large cohort of Korean patients with IBD.

METHODS

A total of 6647 patients with IBD who visited the Asan Medical Center between June 1989 and September 2016 were enrolled in the study. When at least two familial cases existed in our cohort, they were included in the concordance analysis (κ index). The concordance between younger and older members for IBD type [Crohn's disease (CD) and ulcerative colitis (UC)] and phenotypic characteristics such as disease extent and location, disease behavior, the use of medication, and need for surgery were evaluated.

RESULTS

A positive family history of IBD was noted in 216 patients with CD (7.0%) and in 238 patients with UC (6.7%). Of all patients, 167 consanguineous pairs in 146 families were identified. The crude concordance rate for IBD type was 82.6% with a κ index of 0.656 [95% confidence interval (CI): 0.545-0.768, good concordance]. There was mild concordance for disease location in CD (κ = 0.256; 95% CI: 0.007-0.505) and for the use of antitumor necrosis factor agents in UC (κ = 0.354; 95% CI: -0.049-0.757). The concordance for IBD type and several phenotypes in first-degree relative pairs was better than that in the entire pairs.

CONCLUSIONS

Disease type and phenotypic characteristics of patients with familial IBD may be anticipated.

Change in Prevalence of Family History During Long-term Follow-up of Patients With Pediatric-onset Inflammatory Bowel Disease

OBJECTIVES

The aim of the study was to prospectively study changes in prevalence of positive family history (FH+) in pediatric-onset inflammatory bowel disease (IBD) in contrast to previously published cross-sectional data.

METHODS

An observational cohort study was performed using a prospective pediatric-onset IBD database including 485 patients with disease duration ≥10 years as of December 2016. Proband characteristics and FH+ were obtained at diagnosis and subsequently from the database, medical records, and follow-up telephone interviews in 2006 and 2016.

RESULTS

Updated 2016 information was obtained from 322 (66%) patients and included in analysis with median follow-up of 18 years (interquartile range 14, 26). Prevalence of FH+ increased from 13.7% at diagnosis to 26.6% at 20 years for first-degree relatives and from 38.5% to 52.2% for all relatives. At 20-year follow-up, an additional 10.0% of probands had a sibling, 6.1% had a parent, 1.9% had a grandparent, and 4.5% had a cousin diagnosed with IBD. FH+ at diagnosis was associated with greater risk for additional FH+ at 20 years (43% vs 22%, P < 0.001). Non-Jewish Caucasians had significantly lower risk of a FH+ compared to Jewish Caucasians (P = 0.002), but similar risk to African Americans (P = 0.55). FH+ at diagnosis was not associated with disease type (P = 0.33) or age at diagnosis (P = 0.24).

CONCLUSIONS

This prospective study documents changes in family history of IBD in pediatric-onset IBD patients over time. Prevalence of FH+ increased for first-degree and all relatives at 20 years by 12.9% and 13.7%, respectively. FH+ at diagnosis was associated with a 2-fold greater likelihood of subsequent FH+ at 20 years.

Characteristics of inflammatory bowel disease in patients of Roma/Gypsy ethnicity. A case-control study

BACKGROUND

Peculiarities of inflammatory bowel disease (IBD) have been explored in ethnic groups, such as Asians, Hispanics, and Afro-Americans, but not in other ethnic minorities, such as Roma/Gypsies.

METHODS

In a retrospective, hospital-based study, all adult Roma/Gypsy patients included in the IBD databases of seven Spanish centres were identified as cases. For each Roma/Gypsy patient, a Caucasian patient, matched for several demographic features, was searched as a control. Data on phenotypic features, therapeutic requirements, and familial aggregation were recorded.

RESULTS

Sixty-eight Roma/Gypsy patients were identified, 29 of them being women. The mean age at diagnosis of IBD was 24.9±9.5years, and the mean time elapsed since diagnosis was 96.6±72.2months. Roma/Gypsy IBD patients showed a significantly higher rate of familial aggregation (43%) than their Caucasian controls (9%) (p=0.00001). CD in Roma/Gypsies had more often a complicated pattern (mainly penetrating) while UC patients showed a marked trend to more often developing extraintestinal manifestations. In addition, Roma/Gypsy IBD patients had a somewhat greater need for immunosuppressants, biological agents or surgery.

CONCLUSIONS

These are the first data on IBD in Roma/Gypsy patients. Familial aggregation is the most prominent feature in these patients, suggesting a predominant role of genetics in its pathogenesis.

The Phenotype of Celiac Disease Has Low Concordance between Siblings, Despite a Similar Distribution of HLA Haplotypes

The factors determining the presentation of celiac disease are unclear. We investigated the phenotypic concordance and the distribution of human leukocyte antigen (HLA) risk haplotypes in affected siblings. One hundred sibling pairs were included. Clinical and histological parameters and HLA haplotypes were compared between the first diagnosed indexes and their siblings. The phenotype was categorized into gastrointestinal, extra-intestinal, malabsorption/anemia, and asymptomatic. The phenotype was fully concordant in 21 pairs. The most common concordant phenotype was gastrointestinal (14 pairs). Indexes had more anemia/malabsorption and extra-intestinal symptoms than siblings (45% vs. 20%, p < 0.001 and 33% vs. 12%, p < 0.001, respectively). Twenty siblings and none of the indexes were asymptomatic. The indexes were more often women (81% vs. 63%, p = 0.008). They were also more often seronegative (11% vs. 0%, p = 0.03) and younger (37 vs. 43 year, p < 0.001), and had more severe histopathology (total/subtotal atrophy 79% vs. 58%, p = 0.047) at diagnosis. The indexes and siblings were comparable in other disease features. Pairs with discordant presentation had similar HLA haplotypes more often than the concordant pairs. The phenotype was observed to vary markedly between siblings, with the indexes generally having a more severe presentation. HLA did not explain the differences, suggesting that non-HLA genes and environmental factors play significant roles.

Exclusive enteral nutrition protects against inflammatory bowel disease by inhibiting NF‑κB activation through regulation of the p38/MSK1 pathway

Although enteral nutrition therapy for inflammatory bowel disease has been confirmed to be an effective treatment method, the exact mechanism responsible for the effects of enteral nutrition remains unclear. The aim of the present study was to investigate the protective effect of exclusive enteral nutrition (EEN) against colitis, and to elucidate the potential mechanisms by inhibiting p65 activation via regulating the p38/mitogen‑ and stress‑activated protein kinase‑1 (MSK1) pathway. Experiments were performed by establishing dextran sulfate sodium (DSS)‑mice colitis and picrylsulfonic acid solution (TNBS)‑induced rat colitis, and the results demonstrated that EEN treatment attenuated body weight loss, colon length shortening and colonic pathological damage caused by colitis. EEN also inhibited inflammatory cells infiltration and decreased myeloperoxidase and inducible nitric oxide synthase activities. Furthermore, EEN significantly reduced the production of pro‑inflammatory mediators in serum and the colon. Mechanically, EEN suppressed activation of p65 by inhibiting the p38/MSK1 pathway. In conclusion, the present study demonstrated that EEN attenuated DSS‑ and TNBS‑induced colitis by inhibiting p65 activation via regulating the p38/MSK1 pathway, thus suggesting that EEN is effective in the treatment of colitis.

Familial and ethnic risk in inflammatory bowel disease

Familial aggregation in inflammatory bowel disease (IBD) has been established for several decades, reflecting shared genetic and environmental susceptibility. A positive family history remains the strongest recognizable risk factor for the development of IBD and is reported in around 8-12% of IBD patients. Crohn’s disease shows a more frequent familial pattern than ulcerative colitis. The risk of developing IBD in first-degree relatives of an affected proband is increased 4- to 8-fold. The risk for twins and children born from couples who both have IBD is also substantially higher; a cumulative effect of the number of family members affected has been described, with the highest incidence being described for families with three or more affected members. Herein, we review the available evidence regarding familial IBD, and briefly discuss the variation of IBD across different races and ethnicities, hoping to provide a useful update and a practical guide that can serve clinicians as a guide for counseling.

Disease severity and treatment requirements in familial inflammatory bowel disease

PURPOSE

Several studies demonstrate an increased prevalence and concordance of inflammatory bowel disease among the relatives of patients. Other studies suggest that genetic influence is over-estimated. The aims of this study are to evaluate the phenotypic expression and the treatment requirements in familial inflammatory bowel disease, to study the relationship between number of relatives and degree of kinship with disease severity and to quantify the impact of family aggregation compared to other environmental factors.

METHODS

Observational analytical study of 1211 patients followed in our unit. We analyzed, according to the existence of familial association, number and degree of consanguinity, the phenotypic expression, complications, extraintestinal manifestations, treatment requirements, and mortality. A multivariable analysis considering smoking habits and non-steroidal-anti-inflammatory drugs was performed.

RESULTS

14.2% of patients had relatives affected. Median age at diagnosis tended to be lower in the familial group, 32 vs 29, p = 0.07. In familial ulcerative colitis, there was a higher proportion of extraintestinal manifestations: peripheral arthropathy (OR = 2.3, p = 0.015) and erythema nodosum (OR = 7.6, p = 0.001). In familial Crohn's disease, there were higher treatment requirements: immunomodulators (OR = 1.8, p = 0.029); biologics (OR = 1.9, p = 0.011); and surgery (OR = 1.7, p = 0.044). The abdominal abscess increased with the number of relatives affected: 5.1% (sporadic), 7.0% (one), and 14.3% (two or more), p=0.039. These associations were maintained in the multivariate analysis.

CONCLUSIONS

Familial aggregation is considered a risk factor for more aggressive disease and higher treatment requirements, a tendency for earlier onset, more abdominal abscess, and extraintestinal manifestations, remaining a risk factor analyzing the influence of some environmental factors.

Influence of a Positive Family History on the Clinical Course of Inflammatory Bowel Disease

BACKGROUND AND AIMS

Previous studies on the difference in phenotypes and disease course between familial and sporadic inflammatory bowel disease (IBD) have been controversial, although family history is considered to increase the risk of developing IBD.

METHODS

The influence of family history on phenotype and disease course of IBD was analysed in 2805 Korean patients with Crohn's disease (CD) and 3266 with ulcerative colitis (UC). Familial IBD was defined as the existence of one or more first-, second- and/or third-degree relatives affected with CD or UC.

RESULTS

A positive family history of IBD was noted in 191 patients with CD (6.8%) and 212 patients with UC (6.5%). In the patients with CD, the probability of anti-TNF use was higher in the familial cases than in the sporadic cases (56.3 vs 43.4%, respectively, at 10 years, p = 0.019). When analysed after excluding patients who had undergone intestinal resection within 1 year of diagnosis, the cumulative probability of intestinal resection was higher in the familial cases than in the sporadic cases (55.0 vs 32.2%, respectively, at 10 years; p = 0.007). In multivariate analysis, family history was an independent risk factor for the time to first intestinal resection in patients with CD (hazard ratio: 1.61, 95% confidence interval: 1.13-2.29; p = 0.009). In patients with UC, younger age at diagnosis and more females were observed in the familial cases (p < 0.001).

CONCLUSIONS

The present study suggests the possibility of a more aggressive clinical course of CD in familial compared with sporadic cases.

Hospital Admissions, Biological Therapy, and Surgery in Familial and Sporadic Cases of Inflammatory Bowel Disease: A Population-Based Cohort Study 1977-2011

BACKGROUND

Easily accessible predictors of disease course in inflammatory bowel disease (IBD) are scarce, and it remains largely unknown whether a family history of IBD predicts the course of Crohn's disease (CD) and ulcerative colitis (UC). We aimed to compare the course of disease in familial and sporadic cases of IBD in a nationwide cohort study.

METHODS

From national registries, covering a population of 8,295,773 individuals, we obtained information on date and year of diagnosis of IBD cases, gender, age, and family ties. Using Cox regression, we estimated hazard ratios for IBD-related hospitalization, biological treatment, and surgery in familial versus sporadic cases of IBD.

RESULTS

A total of 27,886 IBD cases, including 1006 IBD-relative pairs, were followed-up for up to 16 years, totaling 164,979 person-years. We observed no difference in risk of hospital admissions between familial and sporadic cases of IBD. However, patients with familial CD had significantly higher risk of major surgery than sporadic CD cases after 2 years of disease duration (hazard ratio, 1.62; 95% confidence interval, 1.26-2.07). Also, sensitivity analysis suggested a slightly reduced time from diagnosis to first tumor necrosis factor-α inhibitor treatment among familial CD and UC cases as compared with sporadic cases.

CONCLUSION

We found only minor differences in surgery rates and tumor necrosis factor exposure, between familial and sporadic cases of IBD. These findings may represent purely social rather than functional effects, which is consoling for newly diagnosed CD or UC patients with a family history of IBD.

Host-microbiome interaction in Crohn’s disease: A familiar or familial issue?

An impaired interaction between the gut and the intestinal microbiome is likely to be the key element in the pathogenesis of Crohn’s disease (CD). Family studies have provided invaluable information on CD pathogenesis and on its etiology. Relatives share the same genetic risk of developing the disease as affected subjects. Relatives also exhibit similar features relating to their host-microbiome interaction, namely genetic variants in loci involved in detecting bacteria, a greater sero-reactivity to microbial components, and an impaired intestinal permeability. The burden of environmental factors such as cigarette smoking and dysbiosis also seems to be particularly relevant in these genetically predisposed subjects. Diet is emerging as an important factor and could account for the changing epidemiology of CD in recent years. Despite the pivotal role of genetics in the disease’s pathogenesis (especially in familial CD), screening tests in healthy relatives cannot be recommended.