Epidemiological Characteristics Of Major Abnormal ECG And Study Of MA-ECC And Metabolic Syndrome As Predictive Markers Of Cardiovascular Disease In Shanghai Adults

Aims：1. To evaluate the prevalence and epidemiological characteristics of major abnormalECG (MA-ECG) changes in Shanghai adults.2. To explore the risk factors associated with MA-ECG changes.3. To evaluate the predictive value of Metabolic Syndrome and MA-ECG forCardiovascular disease(CVD).Methods：Firstly, a cross-sectional dataset from a prevalence survey of diabetes and metabolicsyndrome (MetS; Shanghai Diabetes Study [SHDS]) conducted in2007-2008wasanalyzed. This study investigated5,526subjects (20-75years old) from six areas (Huayang,Pengpu, Tianmu, Linfen, Anting and Gongyeyuan) in Shanghai. Data regardingdemographic information, disease history and relevant family history were collected.Physical examination and laboratory tests were performed and subjects underwent a rest12-lead electrocardiogram (ECG) test. ECG records were coded according to theMinnesota criteria and classified as either MA-ECG or non-MA-ECG. The complete datafrom5,364subjects (2003men,3361women) were evaluated.Secondly, the two follow-up datasets from the SHDS and the Shanghai DiabetesStudy II (SHDS II;20-75years old) were pooled to assess the predictive value of MA-ECG for CVD. Participants who had ECG records at the baseline and had been assessedfor CVD were included in this analysis. Patients with evidence of CVD at the baselinewere excluded. Data from2,510subjects (995men and1515women) of the Huayangcommunity (at baseline from September1998to November2001) from the SHDS wereused, for whom follow-up assessments for MetS and CVD were conducted twice(December2003to November2004and October2011to April2012). Data of2,957subjects of the Anting and Huayang from the SHDS II study (1,077men and1,880women)communities were included, and a follow-up study of MetS and CVD was performed between July2011and May2012. Finally,1,637participants from the SHDS (1,059subjects for the first follow-up phase;578for the second follow-up phase) and1,889participants from the first follow-up phase of the SHDS II were included in this study.Results：1. The standardized prevalence of MA-ECG was7.3%(7.0%in men,7.7%inwomen). In both genders, the age-specific prevalence of MA-ECG significantly increasedwith age (Ptrend<0.01). The age-specific prevalence of MA-ECG in the youth, the middleaged and the elderly were2.3%,7.7%, and17.3%, respectively, in men; and3.3%,8.8%and16.4%, respectively, in women (both Ptrend<0.01).2. The three most common MA-ECG forms were arrhythmia (28.8%), bundle branchblock (26.5%) and ST segment depression (20.0%) in men, and they were ST segmentdepression (44.6%), arrhythmia (23.0%) and combined MA-ECG (11.8%) in women.3. Multivariate logistic regression analysis showed that besides age, CHD was theonly independent risk factor of MA-ECG in men, with corresponding ORs of2.33-2.39;while in women, menopause (OR value:1.72-1.85) and hypertension (OR value:1.33-1.34)were main factors related to MA-ECG.4. In SHDS II, after a3.8-year follow-up, the ID of MA-ECG in individuals withoutMA-ECG was10.0/1000person-year (survivors:9.8/1000person-year, death:0.2/1000person-year), compared to12.8/1000person-year (survivors:12.8/1000person-year, death:0) in those with MA-ECG. In SHDS, after a follow-up of11.2years, the incidence density(ID) of CVD for participants without MA-ECG was9.7/1000person-year (survivors:5.9/1000person-year, death:3.8/1000person-year), while it reached24.9/1000person-year (survivors:15.6/1000person-year, death:9.3/1000person-year) in those with MA-ECG.5. Cox regression analysis indicated that when follow-up period was greater than5years, MA-ECG was the only independent risk factor for CVD after adjusting for age andMetS (hazard ratio (95%CI):2.53(1.24-5.18)). Compared with those without MA-ECG atthe baseline, the risk of developing CVD increased by1.5times for people with MA-ECG(P<0.05). However, for participants with <5years of follow-up, MA-ECG was notassociated with the risk of CVD (P=0.235). Conclusions：1. MA-ECG in middle-aged and elderly individuals is prevalent, with arrhythmia andST segment depression being the most frequent forms.2. Age, CHD and hypertension are main risk factors of MA-ECG in Shanghai adults.3. Compared to individuals with normal ECG patterns at baseline, the ID of CVDsignificantly increases in people with MA-ECG.4. MA-ECG has a long-term predictive value on the incidence of CVD after a average11.2-year follow-up period.