Independent relevance of left ventricular hypertrophy for risk of ischaemic heart disease in 25,000 Chinese adults

Abstract

Abstract Background The prevalence of left ventricular hypertrophy (LVH) is strongly related with established cardiovascular disease (CVD) risk factors and, hence, there has been some uncertainty about its independent relevance for ischaemic heart disease (IHD) after taking account of such risk factors. Purpose To examine the associations of LVH with prevalent and incident cases of IHD after adjustment for established risk factors for CVD in a population-based study of Chinese adults. Methods The prospective China Kadoorie Biobank cohort study was conducted in the general population of 5 urban and 5 rural areas in China, with a baseline survey in 2004–2008. A random sample of 24,786 participants had a 12-lead electrocardiogram (ECG) recorded at the second resurvey in 2013–2014. Electronic records of ECG tracings were used to estimate LVH using 5 different criteria (Sokolov, Cornell, Romhilt-Estes, Gubner and Mortara). IHD cases were recorded by linkage to electronic records of hospitalisation, death and disease registries. Cox regression was used to estimate the associations of LVH with prevalent (n=1325) and incident (n=900) cases of IHD after adjustment for age, sex, region, prior vascular disease, smoking, alcohol, SBP, diabetes, lipids and body mass index (BMI). Results The overall prevalence of LVH in the population varied depending on the criteria used for detection (Mortara [10%], Sokolov [14%], Cornell [6%], Romhilt-Estes [4%] and Gubner [1%]). The prevalence of LVH (using Sokolov) increased with age and was higher in men than women (20% vs 10%) and linearly with levels of SBP, but also by ∼10-fold between the 10 regions in China. Irrespective of which criteria were used for detection (Table), LVH was strongly associated with both prevalent and incident cases of IHD after adjustment for age, sex, region and established CVD risk factors. Any one measure of LVH was associated with an adjusted OR (95% CI) of 1.30 (1.10, 1.53) for prevalent IHD and 1.40 (1.20, 1.64) for incident IHD, respectively. Conclusions Overall, 1 in 10 Chinese adults had LVH, and LVH was associated with 30% higher risk of prevalent IHD and 40% higher risk of IHD independent of established CVD risk factors. Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): UK Wellcome Trust