Trajectories in waist circumference and waist-to-height ratio with left ventricular hypertrophy in childhood

Background and objective: Previous studies have shown positive associations of waist circumference (WC) and waist-to-height ratio (WHtR) with left ventricular hypertrophy (LVH) among children and adolescents. However, most of these studies were cross-sectional or limited to only two time points. We aim to estimate the association of trajectories in WC and WHtR with LVH during childhood.

Methods: Data were from the prospective "Huantai Childhood Cardiovascular Health Cohort Study" conducted from 2017 to 2023 in Huantai County, Zibo City, Shandong Province. Group-based trajectory modeling was used to categorize WC into three groups: low-increasing, moderate-increasing, and high-increasing trajectories. Similarly, WHtR was categorized into three groups: stabilizing, decreasing, and increasing trajectories. Linear and log-binomial regression analyses were used to examine the associations of WC and WHtR trajectories with increased left ventricular mass index (LVMI) and LVH.

Results: A total of 946 children were included, with 51.9% being boys and an average age of 8 years at baseline. After adjustment for potential covariates, children in the high-increasing WC group and the increasing WHtR trajectory group had increased LVMI (β = 5.16 g/m^2.7, 95% confidence interval (CI): 4.37, 5.95 and β = 4.91 g/m^2.7, 95% CI: 4.15, 5.68) and a higher risk of LVH [risk ratio (RR) = 5.84, 95% CI: 3.39, 10.05 and RR = 7.38, 95% CI: 4.14, 13.14] compared to the low-increasing WC group and stabilizing WHtR group, respectively. Interestingly, the moderate-increasing WC and decreasing WHtR trajectory groups still have an increased LVMI (β = 2.83 g/m^2.7, 95% CI: 2.05, 3.61 and β = 2.25 g/m^2.7, 95% CI: 1.50, 3.01) and a higher risk of LVH (RR = 2.04, 95% CI: 1.00, 4.15 and RR = 2.23, 95% CI: 1.06, 4.71) compared to the low-increasing WC group and stabilizing WHtR group, respectively. Similar results were found when stratified by sex.

Conclusion: We found the risk of LVH was not fully eliminated among children with a decreasing WHtR trajectory. These findings underscore the need for early prevention and continuous monitoring of WC and WHtR to help prevent future sub-clinical cardiovascular damage in childhood.