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Abstract To compare the predictive value of mortality between left ventricular hypertrophy (LVH) defined by Chinese thresholds and defined by international guidelines in hypertension individuals and investigate better indexation methods for LVH in Chinese population. We included 2454 community hypertensive patients with Left ventricular mass (LVM) and relative wall thickness. LVM was indexed to body surface area (BSA), height2 7 and height 1 7. The outcomes were all‐cause and cardiovascular mortality. Cox proportional hazards models were used to explore the association between LVH and the outcomes. C‐statistics and time‐dependent receiver operating characteristic curve (ROC) was used to evaluate the value of those indicators. During a median follow‐up of 49 months (interquartile range 2–54 months), 174 participants (7.1%) died from any cause (n = 174), with 71 died of cardiovascular disease. LVM/BSA defined by the Chinese thresholds was significantly associated with cardiovascular mortality (HR: 1.63; 95%CI: 1.00‐2.64). LVM/BSA was significantly associated with all‐cause mortality using Chinese thresholds (HR: 1.56; 95%CI: 1.14‐2.14) and using Guideline thresholds (HR: 1.52; 95%CI: 1.08‐2.15). LVM/Height1.7 was significantly associated with all‐cause mortality using Chinese thresholds (HR: 1.60; 95%CI: 1.17‐2.20) and using Guideline thresholds (HR: 1.54; 95%CI: 1.04‐2.27). LVM/Height2.7 was not significantly associated with all‐cause mortality. C‐statistics indicated that LVM/BSA and LVM/Height1.7 by Chinese thresholds had better predictive ability for mortality. Time‐ROC indicated that only LVM/Height1.7 defined by Chinese threshold had incremental value for predicting mortality. We found that in community hypertensive populations, race‐specific thresholds should be used to classify LV hypertrophy related to mortality risk stratification. LVM/BSA and LVM/Height1.7 are acceptable normalization method in Chinese hypertension.

Background Left ventricular mass index (LVMI) has been extensively studied for its relationship with mortality but has been typically assessed at a single time point. We, therefore, describe the trajectory of LVMI in a population with hypertension over 6 years to study the subsequent risk of mortality. Methods and Results We assessed LVMI that was collected during annual health examinations in round 1 (2010–2012), round 2 (2013–2014), and round 3 (2015–2016) with 2 allometric scalings, height2.7, and body surface area, in a cohort of participants with hypertension to identify 6‐year trajectories of LVMI by latent class trajectory modeling. We followed up with participants for mortality by latent trajectory from the last echocardiographic examination (September 17, 2014–December 8, 2016) to December 31, 2018. We calculated mortality hazard ratios by assigned trajectory using Cox proportional hazards models. We obtained data for LVMI from 2453 participants (mean age, 61.80 [SD, 12.14] years, 1428 [58.2%] female). We identified 3 trajectories of LVM/H2.7, characterized by maintained low stable (1298 [52.9%]); moderate stable (935 [38.1%]); high stable (220 [9.0%]), as well as 3 trajectories by LVM/body surface area. During a median follow‐up of 2.15 years, 167 participants developed all‐cause mortality, and 71 were cardiovascular mortality. Only the high stable trajectory was associated with a higher risk of all‐cause mortality compared with the low stable trajectory by LVM/H2.7 or LVM/body surface area (all P

Abstract Massive multiple‐input multiple‐output and non‐orthogonal multiple access (MIMO‐NOMA) with low‐resolution analog‐to‐digital converters (ADCs) have been widely considered for the next‐generation wireless communication systems. However, the performance of the system including power‐scaling law has not been well investigated for the practical low complexity receivers. Employing the additive quantization noise model, we derive asymptotic approximate expressions of the spectrum efficiency for the system with group successive interference cancellation (GSIC) receivers over Rician fading channels. Based on these approximations, we conduct a unified asymptotic analysis for the system with linear, SIC, and GSIC receivers. The analysis reveals the transmission power can be scaled by the number of antennas for the system with GSIC receivers and shows the effects of crucial parameters including the number of groups, resolution bits, and antennas on the performance. Given a quality of service, the minimum data transmission power is also calculated for each user and the corresponding approximate power allocation is derived. The asymptotic analysis and the accuracy of the power allocation approximation are then verified by simulation results. Numerical results also demonstrate that high spectrum efficiency and energy efficiency can be achieved by the system with medium‐resolution ADCs and low complexity maximum ratio combining‐GSIC receivers with a small number of groups.