Novel Score May Help Determine Risk for Newly Diagnosed AF After Ischemic Stroke

The Coronary, Heart failure, Age, stroke SEverity – LipidEmia, Sugar, prior Stroke (CHASE-LESS) score may be useful in identifying the risk for atrial fibrillation (AF) in patients hospitalized for ischemic stroke, according to a study published in Atherosclerosis.

Secondary stroke prevention is optimized by early detection of AF, but long-term cardiac monitoring of patients who have experienced a stroke is costly and not practical. Investigators sought to devise a simple risk score to predict AF in patients who have experienced a stroke in which stroke severity is accounted for, unlike in most currently available scores. Patients thus-identified can then be prioritized for extended ambulatory electrocardiograph monitoring.

The data of 17,976 patients without AF (mean age, 68.8±12.5 years; 39.9% women) who were hospitalized between 2000 and 2013 for ischemic stroke from the Taiwanese National Health Insurance Research Database were analyzed. Participants were randomly assigned to a score development or a validation cohort. The study’s primary endpoint was newly diagnosed AF within 1 year of the indexed stroke.

In order to derive the CHASE-LESS score, independent predictors’ beta coefficients were converted to integer points, with the integer point sum equaling the risk score. Harrell’s c-index was used to evaluate the score’s discriminatory ability in the validation cohort.

There were 4 positive and 3 negative predictors detected. The components of the CHASE-LESS score were: presence of coronary artery disease (+1 point; hazard ratio [HR], 1.26; 95% CI, 1.06-1.50; P =.009), congestive heart failure (+1 point; HR, 1.44; 95% CI, 1.17-1.78; P =.001), age (+1 point for each 10-year increment; HR, 1.36; 95% CI, 1.27-1.45; P <.001), stroke severity (based on the National Institutes of Health Stroke Scale [NIHSS]; +1 point for NIHSS scores between 6 and 13: HR, 1.47; 95% CI, 1.20-1.82; P <.001; and +4 points for NIHSS ≥14: HR, 3.54; 95% CI, 2.98-4.20; P <.001), hyperlipidemia (−1 point; HR, 0.64; 95% CI, 0.52-0.78; P <.001), diabetes (−1 point; HR, 0.68; 95% CI, 0.57-0.80; P <.001), and previous stroke or transient ischemic attack history (−1 point; HR, 0.65; 95% CI, 0.52-0.81; P <.001).

The median CHASE-LESS score was 6 points. Of the participants, 1029 (6.0%) were diagnosed with AF (incidence rate [IR], 60.7 per 1000 person-years). These patients were older and more often women. The range of IRs was from 8.3 per 1000 person-years in the low-risk group (score, 1 to 3) to 240.4 per 1000 person-years in the high-risk group (score ≥10). Discrimination was sufficient in both the development (c-index, 0.730; 95% CI, 0.711-0.748) and validation (c-index, 0.732; 95% CI, 0.703-0.761) cohorts.

Strengths of the CHASE-LESS scoring system include the ready availability of components, easy bedside calculation, determination at hospital admission, and its development based on a representative nationwide cohort that may reduce selection bias and enhance generalizability.

Study limitations include the use of claims data, the inability to determine the nature of AF diagnoses, possible underestimation of incident AF, lack of consideration of sex differences, and an inability to classify ischemic stroke by subtype.

“This novel score could aid clinicians to identify patients at risk of developing [newly diagnosed] AF and help prioritize patients for advanced cardiac monitoring in real-world practice,” noted the authors. They recommended that future research examine sex-specific models of the stroke/AF relationship.

Disclosures: This research was supported in part by the Ministry of Science and Technology [grant number MOST 107-2314-B-705-001].

The authors declared they do not have anything to disclose regarding conflict of interest with respect to this manuscript.

Reference

Hsieh C-Y, Lee C-H, Sung S-F. Development of a novel score to predict newly diagnosed atrial fibrillation after ischemic stroke: The CHASE-LESS score. Atherosclerosis. 2020;295:1-7. doi:10.1016/j.atherosclerosis.2020.01.003