1 Department of Gastroenterology, Hospital Civil de Guadalajara "Fray Antonio Alcalde", Guadalajara, Jalisco.
2 Department of Welfare and Sustainable Development, Centro Universitario del Norte, Universidad de Guadalajara, Colotlán, Jalisco.
3 Biomedical Research Unit 02, Specialties Hospital, Western National Medical Center, Instituto Mexicano del Seguro Social (IMSS), Guadalajara, Jalisco.
4 Department of Internal Medicine, Hospital Civil de Guadalajara "Fray Antonio Alcalde", Guadalajara, Jalisco.
5 Health Sciences University Center, Universidad de Guadalajara, Guadalajara, Jalisco.
6 Department of Philosophical, Methodological and Instrumental Disciplines, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Jalisco.
7 Department of Geriatrics, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City. Mexico.