Risk Factors for Coronary Artery Aneurysms in Children With Kawasaki Disease

Background Coronary artery aneurysm (CAA) remains the most serious cardiovascular complication of Kawasaki disease. We sought to identify consistent risk factors for CAA among large contemporary cohorts from Japan and the United States. Methods We conducted a retrospective cohort study including 42 350 children from the 26th and 27th Japanese Nationwide Kawasaki Disease Surveys (2019–2022) and 1216 children from a multiethnic US cohort. Multivariable logistic regression was used to evaluate associations between clinical variables and CAA at 1 month after disease onset ( Z score ≥2.5). Results In both cohorts, baseline coronary artery dilation at diagnosis ( Z score ≥2.5) was strongly associated with CAA 1 month after disease onset (Japan: odds ratio [OR], 22.7 [95% CI, 19.2–26.7]; United States: OR, 13.4 [95% CI, 8.6–21.0]). Age younger than 6 months and intravenous immunoglobulin resistance were also independently associated with increased risk. These associations were also observed for medium to giant CAAs. Stratified analyses demonstrated that intravenous immunoglobulin resistance was most strongly associated with subsequent CAA among children with normal coronary arteries at diagnosis. Conclusions Among large Japanese and US cohorts, coronary artery dilation at diagnosis and age younger than 6 months were consistent predictors of CAA. These associations were also observed for medium to giant CAA, underscoring their relevance for clinically significant coronary outcomes. Early coronary artery assessment provides important prognostic information and may inform cardiovascular risk stratification and management in children with Kawasaki disease.