Original Article
Incidence and phenotype at diagnosis of inflammatory bowel disease. Results in Spain of the EpiCom studyIncidencia y fenotipo al diagnóstico en la enfermedad inflamatoria intestinal. Resultados del estudio EpiCom en España

https://doi.org/10.1016/j.gastrohep.2015.03.001Get rights and content

Abstract

Introduction

Incidence of inflammatory bowel disease (IBD) is increasing progressively. Few recent epidemiological prospective studies are available in Spain. The Epicom study, a population-based inception cohort of unselected IBD patients developed within the European Crohn's and Colitis Organization, was started in 2010. Vigo is the only Spanish area participating.

Objective

To describe the incidence of IBD in the Vigo area and the phenotypical characteristics at diagnosis and to compare them with previous data available in Spain.

Material and methods

Epidemiological, descriptive, prospective, and population-based study. All incident cases of IBD during 2010 and living in the Vigo area at diagnosis were included. The Copenhagen Diagnostic criteria were used to define cases. Background population at the start of the study was 579,632 inhabitants. Data were prospectively entered in the EpiCom database.

Results

A total of 106 patients were included (57.5% men, median age 39.5 years). Of them 53 were diagnosed of as Crohn's disease (CD), 47 ulcerative colitis (UC) and six IBD unclassified (IBDU). The incidence rate per 100,000 per year for patients aged 15 years or older was 21.4 (10.8 for CD, 9.4 for UC, 1.2 IBDU). Including pediatric population incidence rates were 18.3 (10.3 CD, 8.7 UC, 1.2 IBDU). Median time since onset of symptoms until diagnosis was 2 months.

Conclusions

The incidence rate of IBD in Vigo is the highest compared to former Spanish cohorts, especially in CD patients. Median time since onset of symptoms until diagnosis is relatively short.

Resumen

Introducción

La incidencia de la enfermedad inflamatoria intestinal (EII) va paulatinamente en aumento. En España escasean los estudios epidemiológicos prospectivos recientes. En 2010 se inició el estudio Epicom, un estudio demográfico de cohortes de inicio de pacientes con EII no seleccionados que se desarrolla en el marco de la Organización Europea de Enfermedad de Crohn y Colitis Ulcerosa. La de Vigo es la única zona española participante.

Objetivo

Describir la incidencia de la EII en el área de Vigo y las características fenotípicas en el momento del diagnóstico y compararlas con los datos previos disponibles sobre España.

Material y métodos

Estudio epidemiológico, descriptivo, prospectivo y demográfico. Se incluyeron todos los casos de EII incidentes durante el año 2010 en residentes de la zona de Vigo. Para definir los casos se emplearon los criterios diagnósticos de Copenhague. La población del entorno al inicio del estudio era de 579.632 habitantes. Los datos se incluyeron en la base de datos EpiCom de manera prospectiva.

Resultados

Se incluyó un total de 106 pacientes (57,5% varones, mediana de edad de 39,5 años). De ellos, 53 fueron diagnosticados con enfermedad de Crohn (EC), 47 con colitis ulcerosa (CU) y 6 con EII no clasificado (EIINC). La tasa de incidencia anual por 100.000 para pacientes de 15 años o más fue de 21,4 (10,8 para EC; 9,4 para CU; 1,2 para EIINC). Si se incluye la población pediátrica, la tasa de incidencia fue de 18,3 (10,3 para EC; 8,7 para CU; 1,2 para EIINC). La mediana de tiempo para la aparición de los síntomas hasta el diagnóstico fue de 2 meses.

Conclusiones

La tasa de incidencia de la EII en Vigo es la más alta en comparación con antiguas cohortes españolas, sobre todo en el caso de los pacientes con EC. La mediana de tiempo para la aparición de los síntomas hasta el diagnóstico es relativamente breve.

Introduction

Inflammatory bowel diseases (IBD), Crohn's disease (CD) and ulcerative colitis (UC) are chronic inflammatory diseases of the gastrointestinal tract of unknown etiology. High quality epidemiological studies of unselected patients are essential in order to assess the real burden of IBD. Incidence and prevalence are highly variable among different countries, with IBD being more common in industrialized than in non-industrialized countries. For adult patients, the incidence rates vary between 0.1–20.2 for CD and 0.5–31.5 per 100,000 person-years for UC.1, 2 Traditionally, North America, Scandinavia and United Kingdom are considered the areas of highest incidence. In recent years, incidence is progressively increasing in all geographic settings,1, 3, 4 but there are studies that show a change in this trend, with stabilization or decrease in areas with previously high incidence.5, 6 The reasons for this rising incidence are uncertain. An increase in disease awareness, improved access to healthcare and diagnostic procedures, or true changes in life-style and environmental factors as a consequence of the socio-economic transition from ‘developing’ to ‘developed’ in many countries could all account for some of the changes.7, 8

Population-based inception cohorts, including incident (newly diagnosed) patients, offer the most valid picture when studying the occurrence and natural course of the disease. However, due to difficulties in executing and maintaining population-based cohorts, the capability of performing this type of study is limited in most countries.9

Spain is considered a low-incidence region compared with northern European countries,5 but few recent prospective studies are available and they show variable data in terms of incidence.10, 11, 12, 13, 14, 15, 16, 17

The European Crohn's and Colitis Organization's (ECCO) Epidemiological Committee (EpiCom) study is a prospective, population-based cohort of unselected IBD patients diagnosed in 2010 within well described geographical areas, aiming to investigate if an east-west gradient exists across European countries and to identify environmental factors involved in these differences. The study was carried out in 31 centers from 22 European countries, covering a total background of 10.1 million people.2 In Spain, Vigo is the only area participating in the EpiCom study.

The aim of this study within the ECCO-EpiCom cohort was to describe the incidence of IBD in the Vigo area and the disease phenotype characteristics at diagnosis as well as to compare them with previous data available in Spain.

Section snippets

Study centers

This is an epidemiological, descriptive, prospective, population-based study developed in the Vigo area. Vigo area is located in the South-West of Galicia, in the Atlantic coast, and includes 26 municipalities. Cases were collected from hospitals included in the public health system (Complexo Hospitalario Universitario de Vigo and Hospital POVISA). Patients who belonged to Vigo area and were diagnosed in private Hospitals (mainly Hospital POVISA, Hospital Fatima and Hospital Perpetuo Socorro)

Statistical analysis

Background population at the start of the study was 579.632 inhabitants. The incidence rate (number of new cases/100,000 inhabitants) was calculated. Age-standardized annual incidence rates were obtained using the European Standard population using 10-year age groups (from 15 to 65 years), and including also a pediatric specific group and a >65 years old group. The qualitative variables are expressed as number (n) and percentage. The quantitative variables are expressed as the mean and range.

Incidence and disease phenotype characteristics of the Vigo 2010 cohort

During the study period, 106 patients were diagnosed of IBD (102 aged 15 years or older, four pediatric patients). Of them, 53 (50%) were diagnosed with CD, 47 (44.3%) with UC and 6 (5.7%) IBDU. The incident rate (per 100,000 per year) for patients aged 15 years or older was 21.4 (10.8 for CD, 9.4 for UC and 1.2 for IBDU). Including pediatric population, incidence was reduced to 18.3 (10.3 CD, 8.7 UC and 1.1 IBDU). Age-standardized incidence rates are shown in Fig. 1.

With respect to gender, 61

Discussion

The results of our study, compared with previously published data (Table 2, prospective studies), show the highest incidence rate described so far in Spain, mainly due to an increasing incidence of CD. This agrees with a recently published systematic review that reported an increasing incidence of IBD worldwide.1 Focusing in Spain, the trend of the incidence of CD shows a notable increase in the last decade.23

Comparing different geographical areas could lead to a bias in the interpretation of

Funding

This work has not received any public or private funding.

Conflict of interest

The authors declare no conflict of interest.

Acknowledgement

We thank Johan Burisch (Copenhagen), Pia Munkholm (Copenhagen) and Peter Lakatos (Budapest) for their useful comments.

References (37)

  • J. Burisch et al.

    East-West gradient in the incidence of inflammatory bowel disease in Europe: the ECCO-EpiCom inception cohort

    Gut

    (2014)
  • B.A. Jacobsen et al.

    Increase in incidence and prevalence of inflammatory bowel disease in northern Denmark: a population-based study, 1978–2002

    Eur J Gastroenterol Hepatol

    (2006)
  • S. Shivananda et al.

    Incidence of inflammatory bowel disease across Europe: is there a difference between north and south? Results of the European Collaborative Study on Inflammatory Bowel Disease (EC-IBD)

    Gut

    (1996)
  • F. Molinié et al.

    Opposite evolution in incidence of Crohn's disease and ulcerative colitis in Northern France (1988–1999)

    Gut

    (2004)
  • J. Burisch et al.

    Inflammatory bowel disease epidemiology

    Curr Opin Gastroenterol

    (2013)
  • C.C. Frangos et al.

    Inflammatory bowel disease: reviewing an old study under a new perspective

    Gut

    (2007)
  • J. Burisch

    Crohn's disease and ulcerative colitis. Occurrence, course and prognosis during the first year of disease in a European population-based inception cohort

    Dan Med J

    (2014)
  • E. Brullet et al.

    Epidemiological study on the incidence of inflammatory bowel disease in 4 Spanish areas. Spanish Group on the Epidemiological Study of Inflammatory Bowel Disease

    Med Clin (Barc)

    (1998)
  • Cited by (0)

    View full text