CHADS2 Stroke Risk Stratification in Atrial Fibrillation Patients; Community Based Comparison Study

Abstract

Atrial fibrillation (AF) is very common cardiovascular disorder and a major health problem in North Africa. AF associated with increase the risk of stroke and hospitalization. Objectives: To compare stroke risk factors among community people who have atrial fibrillation and those who are not using both CHADS2 Score and Community Stroke Risk Classification (CSRC). Methodology: This was community based descriptive cross-sectional comparison study. Area: North Africa (north of Libya, the capital Tripoli). Time: 2014, one year. Population: Sampling was done from a large cohort of individuals living in the community. Two groups where selected, AF group, which consists of 519 patients who had AF, and control group (602 apparently healthy individuals) who does not have AF. The two groups were selected and matched having the same confounding characters. Both groups were interviewed and screened using CHADS2 Questionnaire as well a local Libyan classification of stroke risk factors called Community Stroke Risk Classification (CSRC). Results: Among population screened (8016) over five years (from 2010 to 2014) the prevalence of AF was 7% (519 patients) and the main age of AF group was 61.2 years with range of 22->70 and SD±16.4. The main age of control group was younger than AF group with main age of 52 years (P<0.001). AF increased with age with more than 89.8% was over frothy years old with males domination over females (P<0.0001). Comparison between AF group and control in stroke risk factors in CHADS2 score showed significant dominations of risk factors over AF group than control; CHF (46.4% versus 24.3% respectively) (P<0.0001). Hypertension (49% versus 34% respectively) (P<0.0001), DM (56% versus 38% respectively) (P<0.0001), TIA (43% versus 19.4% respectively) (P<0.0001) and finally stroke prevalence (Prior stroke) was significantly higher among AF group compared with control group (84% versus 0.9% respectively) (P<0.0001). CHADS2 score was very high among AF group compared to control, with AF group 97.8% had risk points of stroke, where only 2.7% had no risk, where in control group; 66.8% had risk and 33.3% had no stroke risk. High CHADS2 score with ≥3 risk points were dominated with AF group compared with control (P<0.0001) (83.6% versus 66.8% respectively). Community Stroke Risk Classification (CSRC) showed dominations of higher score of ≥3 risk factors among AF group compared with control (66.8% versus 23%) (P<0.0001). However in the intermediate score with 1-2 risk factors, control group was dominated (43.7%) over AF group (31.2%) (P <0.0001). Conclusion: AF is a major risk factor of stroke among north African population (Libya). CHADS2 and CSRC classification scores are very useful tools to be used to evaluate the risk factors of stroke in community population having AF or not.