Clinical and Sociodemographic Characteristics of Inflammatory Bowel Disease in Mexico: A Multi-center and Nationwide Study (EPIMEX-IBD)

Abstract

BACKGROUND: The global incidence of Inflammatory Bowel Disease (IBD), Ulcerative Colitis (UC) and Crohn's Disease (CD), is increasing. However, there are no epidemiological or descriptive data from a nationwide study in Mexico. The aim of this study is to describe the clinical and socio-demographical characteristics of Mexican patients with IBD from whole country. METHODS: This is a multi-center study where gastroenterologists and colorectal surgeons were involved from 14 states in Mexico who collected clinical and socio-demographic data of all patients with definitive diagnosis of UC, CD and Indeterminate Colitis (IC) during the period between March and June 2017. Data were analyzed using the statistics program SPSS v.24. A p value <0.05 was considered significant. RESULTS: A total of 1,101 patients was studied, 908 (82.5%) with UC, 174 (15.8%) with CD and 17 (1.5%) with IC from 14 states in Mexico. Female represented 47.2% and male 52.8%. The median age at the time of inclusion in the study was 46 years. The median age at diagnosis was 37 years. Extra-intestinal manifestations were present in 39.1% of patients with UC and 32.8% with CD. The most frequent extra-intestinal manifestations were: arthralgia (28.3%), arthritis (10.8%), osteopenia (5.8%), osteoporosis (3.9%), sacroiliitis (2.8%), primary sclerosing cholangitis (1.8%) and uveitis (1.5%). Most of the patients were born in the most industrialized States of the country, 21.9% being born in Mexico City; 20.2% in Jalisco; 8.8% in State of Mexico and 4.2% in Nuevo Leon. Patients that received attention at public institutions represented 79.7% of the total sample and those which were treated at private centers only 20.3%. In the case of UC: 52.6% of patients had extensive colitis (E3), 17.4% left-sided colitis (E2), 20% distal colitis and 10% no specified extension. In the case of CD: 34.5% of patients reported the following location: colonic (L2), 29.3% ileo-colonic (L3), 17.2% ileal (L1), 2.9% upper tract involvement (L4) and 16.1% no specified location. Most of the patients were under treatment with 5-aminosalicylates (66.3% and 65.5% respectively), followed by steroids (28.7% and 46% respectively), thiopurines (24.9% and 42% respectively) and anti-TNF therapy (16.2% and 37.4% respectively). In the case of UC, 1.9% required surgical treatment and in the case of CD, 17.8%. Patients with CD required surgical treatment more often compared with those with UC (OR=11.36, IC 95%=6.13-21.06, P=0.000). Employee state was associated with higher risk to have diagnosis of UC compared to CD (OR=1.96, IC 95%=1.40-2.75, P=0.000). CONCLUSION(S): In this first multicenter study at national level, UC was 6 times more frequent than CD. The most frequent extent of UC was pancolitis, while in CD was colonic location. Socio-demographic and clinical variables were associated with different clinical outcomes in Mexican patients with IBD.