关键词: 川崎病, 黏膜皮肤淋巴结综合征, 流行病学研究, 冠状动脉疾病, 疾病特征

Abstract: Background　Kawasaki disease （KD） is a systemic vasculitis associated with coronary artery lesion （CAL），which can lead to cardiomyopathy，myocardial infarction and death. At present，the incidence of KD is increasing year by year and has become the most common cause of acquired heart disease in children，significantly affecting the occurrence of long-term cardiovascular events during adulthood. Understanding the epidemiological characteristics and influencing factors of the disease is of great significance for reducing the incidence of the disease. Objective　To discuss the epidemiological characteristics of KD in Gansu from three aspects：demographic characteristics，time distribution and regional differences，in order to provide scientific basis for the management and prevention of KD in the western region. Methods　The 581 children with KD admitted to the Lanzhou University Second Hospital from January 2012 to December 2019 were selected as the research objects. According to the CAL status of the selected children within 1 month，the children with KD were divided into KD combined with CAL （CAL group） and without CAL （NCAL group）. According to the age of onset，they were divided into four age groups：≤1 year old，>1-3 years old，>3-6 years old and >6 years old. A unified questionnaire was used to collect general information （age，gender，ethnicity，time of onset，etc.） and thecoronary artery color Doppler ultrasound results. Results　（1）Demographic characteristics：among the 581 hospitalized children，the median age of onset of KD was 1.9 （1.2，3.2）years old. The ratio of male to female was about 1.9∶1 and the proportion of males decreased linearly with the increase of age （χ2trend=5.100，P<0.05）. （2）Temporal distribution：the overall number of KD showed an upward trend in different years （χ2trend=122.348，P<0.001）. There were significant differences in the distribution of KD cases in each season（χ2=12.418，P<0.05）. The proportion of children in spring was negatively correlated with their age groups（rs=-1，P<0.001），of which in autumn was positively correlated with the age groups（rs=1，P<0.001）. （3）Regional differences：combined with the geographical location，natural conditions and the current situation of regional economic and social development，Gansu Province was divided into five regions：Hexi，Longzhong，Longdong，Longdongnan and ethnic regions. According to the daily living expenses of urban residents，the average wage of workers and the level of social and economic development，Gansu Province was divided into four types of economic areas from high to low. The number of medical cases increased year by year in Longzhong region（χ2trend=86.011，P<0.001），Longdongnan region （χ2trend=23.848，P<0.001） and ethnic region （χ2trend=17.463，P<0.001）. The number of medical cases in economic class one （χ2trend=54.551，P<0.001），economic class two （χ2trend=20.586，P<0.001），economic class three （χ2trend=14.844，P<0.001） and economic class four （χ2trend=36.013，P<0.001） increased year by year. （4）Influencing factors：the number of KD cases of combined CAL （χ2trend=95.041，P<0.001） and NCAL （χ2trend=38.719，P<0.001） between different years showed an upward trend，especially in the CAL group （χ2trend=9.502，P<0.05）；multivariate Logistic regression analysis showed that age〔OR=3.011，95%CI（1.313，6.907）〕，gender〔OR=1.634，95%CI （1.137，2.349 ）〕and four economic areas〔OR=1.772，95%CI（1.172，2.679）〕were the independent risk factors of CAL. Conclusion　The number of patients with KD in Gansu had a tendency of growth by year，especially in the CAL group.The burden of disease was severe，especially in economically underdeveloped areas. In order to reduce the incidence of KD and its complications，it is necessary to increase public awareness of the severity of the disease，and properly increase prevention and control efforts for male infants in summer （try to intervene in advance for people at high risk of KD，such as immune regulation），establish and improve the KD follow-up mechanism，strengthen the training of primary physicians，conducting multi-center research and continuously monitorthe epidemiological characteristics of KD to obtain important information related to the best prevention strategy，early diagnosis，treatment timing and treatment choice.

Key words: Kawasaki disease, Mucocutaneous lymph node syndrome, Epidemiologic studies, Coronary artery disease, Disease attributes