Genetic Risk Factors for Diverticular Disease-Emerging Evidence

Genetic, epigenetic and environmental factors in diverticular disease: systematic review

BACKGROUND

Diverticulosis is a normal anatomical variant of the colon present in more than 70% of the westernized population over the age of 80. Approximately 3% will develop diverticulitis in their lifetime. Many patients present emergently, suffer high morbidity rates and require substantial healthcare resources. Diverticulosis is the most common finding at colonoscopy and has the potential for causing a significant morbidity rate and burden on healthcare. There is a need to better understand the aetiology and pathogenesis of diverticular disease. Research suggests a genetic susceptibility of 40-50% in the formation of diverticular disease. The aim of this review is to present the hypothesized functional effects of the identified gene loci and environmental factors.

METHODS

A systematic literature review was performed using PubMed, MEDLINE and Embase. Medical subject headings terms used were: 'diverticular disease, diverticulosis, diverticulitis, genomics, genetics and epigenetics'. A review of grey literature identified environmental factors.

RESULTS

Of 995 articles identified, 59 articles met the inclusion criteria. Age, obesity and smoking are strongly associated environmental risk factors. Intrinsic factors of the colonic wall are associated with the presence of diverticula. Genetic pathways of interest and environmental risk factors were identified. The COLQ, FAM155A, PHGR1, ARHGAP15, S100A10, and TNFSF15 genes are the strongest candidates for further research.

CONCLUSION

There is increasing evidence to support the role of genomics in the spectrum of diverticular disease. Genomic, epigenetic and omic research with demographic context will help improve the understanding and management of this complex disease.

Distribution and Characteristics of Colonic Diverticula in Northern China

OBJECTIVE

The prevalence of colonic diverticula is rising in eastern countries, possibly related to aging and the adoption of a western lifestyle. However, limited data exist regarding the distribution and endoscopic features of colonic diverticula in this population. This study aimed to assess the number, size, depth, and location of colonic diverticula in our study cohort.

PATIENTS AND METHODS

We collected data from patients who underwent colonoscopy at the Endoscopy Center of Tianjin Medical University General Hospital and Bao Di Clinical College of Tianjin Medical University. We thoroughly evaluated and documented any colonic diverticula encountered during the procedures. Logistic regression analysis was employed to explore associations between participant characteristics and the presence of colonic diverticula.

RESULTS

Our study included a total of 27,021 eligible patients from our colonoscopy database, among whom 1529 individuals (5.67%) exhibited one or more diverticulosis. Patients with colonic diverticula (mean age: 58.6) were significantly older and exhibited a male predominance compared with those without diverticula. Cases of right-sided, left-sided, and bilateral diverticulosis were recorded in 1161 (76.0%), 170 (11.1%), and 198 patients (12.9%), respectively. Patients with right-sided diverticula (mean age: 55.2), more common in males, were younger than those with left-sided diverticula (mean age: 67.1, P < 0.05), which were more frequent in females (P < 0.001). Individuals aged 60 years or older (odds ratio: 4.32, P < 0.001) and those with bilateral diverticulosis (odds ratio: 21.2, P < 0.001) had a higher likelihood of having a greater burden of diverticula.

CONCLUSION

Colonic diverticula in Northern China predominantly manifests as right-sided, more common in males, and associated with older age. Notably, patients with right-sided diverticulosis tend to be younger than those with left-sided diverticula. In addition, a higher burden of diverticula is more prevalent in individuals aged 60 years or older and those with a bilateral distribution pattern.

Development of a Polygenic Risk Score to Predict Diverticulitis

BACKGROUND

Despite its prevalence and associated morbidity, we remain limited in our ability to predict the course of a patient with diverticular disease. Although several clinical and genetic risk factors have been identified, we do not know how these factors relate to one another.

OBJECTIVE

Our aim was to determine whether a polygenic risk score could improve risk prediction for diverticulitis and recurrent diverticulitis compared with a model using only clinical factors.

DESIGN

This is an observational study.

SETTING

The study examines the predictive ability of a polygenic risk score for diverticulitis developed using prior genome-wide association studies and validated using the MyCode biobank.

PATIENTS

This study included patients of European ancestry in the Geisinger Health System who were enrolled in the MyCode Community Health biobanking program.

MAIN OUTCOME MEASURES

The ability of a polygenic risk score to predict diverticulosis, diverticulitis, and recurrent diverticulitis was the main outcome measure of this study.

RESULTS

A total of 60,861 patients were included, of whom 9912 (16.3%) had diverticulosis or diverticulitis (5015 with diverticulosis and 4897 with diverticulitis). When divided into deciles, our polygenic risk score stratified patients by risk of both diverticulosis and diverticulitis with a 2-fold difference in disease risk between the highest and lowest deciles for diverticulitis and a 4.8-fold difference for recurrent complicated diverticulitis. When compared with clinical factors alone, our polygenic risk score was able to improve risk prediction of recurrent diverticulitis.

LIMITATIONS

Our population is largely located in a single geographic region and were classified by disease status, using international classification of diseases codes.

CONCLUSIONS

This predictive model stratifies patients based on genetic risk for diverticular disease. The increased frequency of recurrent disease in our high-risk patients suggests that a polygenic risk score, in addition to other factors, may help guide the discussion regarding surgical intervention. See Video Abstract .

DESARROLLO DE UNA PUNTUACIN DE RIESGO POLIGNICO PARA PREDECIR LA DIVERTICULITIS

ANTECEDENTES:A pesar de su prevalencia y morbilidad asociada, nuestra capacidad para predecir el curso en un paciente con enfermedad diverticular sigue siendo limitada. Si bien se han identificado varios factores de riesgo clínicos y genéticos, no sabemos cómo se relacionan estos factores entre sí.OBJETIVO:Determinar si una puntuación de riesgo poligénico podría mejorar la predicción del riesgo de diverticulitis y diverticulitis recurrente en comparación con un modelo que utiliza solo factores clínicos.DISEÑO:Un estudio observacional que examina la capacidad predictiva de una puntuación de riesgo poligénico para la diverticulitis desarrollada usando estudios previos de asociación amplia del genoma y validada usando el biobanco MyCode.ÁMBITOS Y PACIENTES:Pacientes de ascendencia europea en el Sistema de Salud Geisinger que estaban inscritos en el programa de biobancos MyCode Community Health.PRINCIPALES MEDIDAS DE VALORACIÓN:La capacidad de una puntuación de riesgo poligénico para predecir diverticulosis, diverticulitis y diverticulitis recurrente.RESULTADOS:Se incluyeron un total de 60.861 pacientes, de los cuales 9.912 (16,3%) presentaban diverticulosis o diverticulitis (5.015 con diverticulosis y 4.897 con diverticulitis). Cuando se dividió en deciles, nuestra puntuación de riesgo poligénico estratificó a los pacientes según el riesgo de diverticulosis y diverticulitis con una diferencia de 2 veces en el riesgo de enfermedad entre los deciles más alto y más bajo para diverticulitis y una diferencia de 4,8 veces para diverticulitis complicada recurrente. En comparación con los factores clínicos solos, nuestra puntuación de riesgo poligénico pudo mejorar la predicción del riesgo de diverticulitis recurrente.LIMITACIONES:Nuestra población se encuentra en gran parte en una sola región geográfica y se clasificó por estado de enfermedad utilizando códigos de clasificación internacional de enfermedades.CONCLUSIONES:Este modelo predictivo estratifica a los pacientes en función del riesgo genético de enfermedad diverticular. La mayor frecuencia de enfermedad recurrente en nuestros pacientes de alto riesgo sugiere que un puntaje de riesgo poligénico, además de otros factores, puede ayudar a guiar la discusión sobre la intervención quirúrgica. (Traducción- Dr. Ingrid Melo ).

Seasonal variations in acute diverticular disease hospitalisations in New Zealand

PURPOSE

Seasonal variation of acute diverticular disease is variably reported in observational studies. This study aimed to describe seasonal variation of acute diverticular disease hospital admissions in New Zealand.

METHODS

A time series analysis of national diverticular disease hospitalisations from 2000 to 2015 was conducted among adults aged 30 years or over. Monthly counts of acute hospitalisations' primary diagnosis of diverticular disease were decomposed using Census X-11 times series methods. A combined test for the presence of identifiable seasonality was used to determine if overall seasonality was present; thereafter, annual seasonal amplitude was calculated. The mean seasonal amplitude of demographic groups was compared by analysis of variance.

RESULTS

Over the 16-year period, 35,582 hospital admissions with acute diverticular disease were included. Seasonality in monthly acute diverticular disease admissions was identified. The mean monthly seasonal component of acute diverticular disease admissions peaked in early-autumn (March) and troughed in early-spring (September). The mean annual seasonal amplitude was 23%, suggesting on average 23% higher acute diverticular disease hospitalisations during early-autumn (March) than in early-spring (September). The results were similar in sensitivity analyses that employed different definitions of diverticular disease. Seasonal variation was less pronounced in patients aged over 80 (p = 0.002). Seasonal variation was significantly greater among Māori than Europeans (p < 0.001) and in more southern regions (p < 0.001). However, seasonal variations were not significantly different by gender.

CONCLUSIONS

Acute diverticular disease admissions in New Zealand exhibit seasonal variation with a peak in Autumn (March) and a trough in Spring (September). Significant seasonal variations are associated with ethnicity, age, and region, but not with gender.

THE RELATION BETWEEN THE DIET AND THE DIVERTICULITIS PATHOPHYSIOLOGY: AN INTEGRATIVE REVIEW

BACKGROUND

Diverticulitis is an acute inflammatory process that affects individuals with diverticular disease. Given the sharp increase in the diagnostic rate of such a pathological process, there was also an increased interest in elucidating the possible causes related to the development of this clinical condition. Among the main factors investigated, diet excels, the object of study of this integrative literature review.

METHODS

After searching the virtual health library and PubMed databases, five prospective cohort studies were selected that best answered the guiding question: "Is there a relationship between diet and the incidence of diverticulitis?".

RESULTS

It was observed that the high intake of red meat and the low intake of dietary fiber were the most strongly associated dietary factors with the incidence of this inflammatory process.

CONCLUSION

Therefore, it is evident that choosing healthy eating habits can considerably reduce the incidence of diverticulitis and, consequently, potentially more serious complications directly related to it.