STROKE RISK CLASSIFICATION BY CHADS2 SCORE IN COMMUNITY POPULATION IN ABSENCE OF ATRIAL FIBRILLATION

Abstract

CHADS2 score is a proven, simply calculated, essential tool for estimating cardioembolic risk (mainly stroke) in
patients with nonvalvular atrial fibrillation (AF). The CHADS2 score is used in clinical practice to guide decisions
regarding antiplatelet and anticoagulation therapy. The study aimed to evaluat the performance of the CHADS2
score & Community Stroke Risk Classification (CSRC) to classify stroke risk factors in population without AF. This
study was conducted as a community based descriptive cross-sectional study in North Africa (North West of Libya),
among individuals living in Tripoli area "the capital". It was done by Department of Community & Family Medicine, Faculty of Medicine, University of Tripoli. Duration of the study was five years from 1/1/2010 to 31/12/2014.
Data was collected using CHADS2 and CSRC scores; Total of 7497 individuals (52.8% males & 48.2% females)
were interviewed by taking detailed histories (present, past, medical, hospital admission), checking of any available
investigations, discharge letters and medical reports and perform medical examinations. Among 7497 screened,
64.2 % (4814) had risk factors (RF) of stroke and 35.8% (2682) have no risk on CHADS2 score corresponds to low
stroke risk. Among population having CHADS2 risk score, 64.3% (3096) have intermediate risk score, corresponds
to intermediate or moderate stroke risk. 1719 (35.7%) had high risk score corresponds to a greater high stroke risk.
On Community Stroke Risk Classification (CSRC), majority of the population having stroke risk score grades with
one or more risk factors (64.2%). Among 4814 had risk factors of stroke, The analysis showed significant difference
in CSRC score grades (P<0.01), the majority of the population having intermediate score grades (1-2
RF)(69.4%)(P<0.001), IRS1 (41.4%) and IRS2 (27.9%). High score prevalence (≥3 RF) was 30.6%, with decrease
in percentages with HRS3 (16.5%), HRS4 (9.5%), HRS5 (3.7%) and the lowest is HRS6 (0.9%). Males showed
significant raise compared with females in all score grades especially in intermediate score risk (1-2 RF) (P<0.004).
Intermediate score (1-2 RF) is dominated in all study age groups compared with high scores (3-6 RF)(P<0.001);
16-49 years (67% for 1-2 RF, 33% for 3-6 RF) and 50-80 years (51.1% for 1-2RF, 48.5% for 3-6RF). Hypertension
and Diabetes were the major risk factors of stroke on all scores and highest among intermediate score (1-2 RF)
(P<0.001). This study confirmed that stroke is a major public health problem in North Africa. CHADS2 & CSRC
scores are very useful and simple method to classify stroke among population without AF.