Incidence rate of recurrent Kawasaki disease and related risk factors: from the results of nationwide surveys of Kawasaki disease in Japan

To investigate the incidence of recurrent Kawasaki disease, and to discuss some of the potential risk factors, data of the 13th and 14th nationwide surveys of Kawasaki disease in Japan were analyzed. To calculate the rate of recurrence, 10 679 patients with 31 501.9 person-years were observed. The mean observation period was 2.95 y. The rate of recurrence was 6.89 per 1000 person-years, with a high incidence within the 12 mo following the first episode. Conclusion: The incidence was high among those under 3 y of age and those with cardiac sequelae during the first episode. None of the other factors affected the incidence.