ABSTRACT
Objective To study the prevalence of dilated cardiomyopathy and the quasi-latent Keshan disease in villages of non-endemic areas of six Keshan disease endemic provinces in China,and to provide reference values for proposing a elimination standard of keshan disease.Methods County,township and village was selected as the study area by using multi-stage sampling in non-Keshan disease areas of Sichuan,Shanxi,Henan,Shandong and in Keshan disease areas of Chongqing and Yunnan.In each county two townships were selected and in each township one village was chosen.The residents of the villages sampled were surveyed by questionnaire,physical examination,electrocardiogram (ECG) and cardiac echocardiography.Suspected dilated cardiomyopathy patients had chest X-ray.Dilated cardiomyopathy patients were diagnosed according to the criteria proposed by 2006 World Health Organization/International Society and Federation of Cardiology (WHO/ISFC).Results The number of investigated villages was 126 and 54 139 people were surveyed by questionnaire and clinical examination.Ten patients with dilated cardiomyopathy were found,the prevalence was 18.47/100 000(10/54 139),and its 95％ confidence interval was 18.11/100 000-18.84/100 000.A total of 197 patients with quasi-latent Keshan disease were found,the prevalence was 363.88/100 000 (197/54 139),and its 95％ confidence interval was 362.27/100 000-365.49/ 100 000.The prevalence of male quasi-latent Keshan disease was 353.34/100 000(83/23 490) and of female was 372.07/100 000(114/30 639).The number of subjects with normal and abnormal ECG was 45 222 and 8917,respectively,and the rate of abnormal ECG was 16.47％.The highest rate of abnormal ECG was 38.28％ (1585/4141) in Chongqing.The lowest rate of abnormal ECG was 8.10％ (1175/14 507) in Yunnan.The highest detection rate of T wave and ST segment changes was 4.67％ (2528/54 139).In abnormal ECG indices,the detection rate of Henan,Shandong and Chongqing was higher,and all of them were higher than 10.0％.Conclusions We suggest that the reference baselines of dilated cardiomyopathy and quasi-latent Keshan disease in Keshan disease areas of the six provinces in the south of China be 18.47/100 000 and 363.88/100 000,respectively.