Objective:The aim of the study was to know the epidemiological behavior and associations of AF in the Mexican population. Materials and methods: Eight thousand six hundred and eighty-six patients from 38 cardiologists participating in REMECAR were analyzed. They were divided by gender and age, the comorbidities studied were obesity, chronic kidney disease (CKD), high blood pressure (HBP), diabetes mellitus (DM), dyslipidemia, stroke, chronic obstructive pulmonary disease (COPD), hypothyroidism, heart failure (HF), and ischemic heart disease (IHD). Program used: IBM SPSS Statistic. Results: AF was diagnosed in 498 patients (5.7%), with higher prevalence in men (6.1% vs. 5.3%) and older age in women (74.3 ± 12.1 vs.