Background and aims: High waist circumference (WC) is associated with left ventricular mass index (LVMI) in childhood. However, no studies have assessed the association between WC change and left ventricular hypertrophy (LVH) in childhood. This study aimed to investigate the association between change in WC status over 2 years on LVH among Chinese children.

Methods and results: Data were from a population-based prospective cohort study in China. Children without LVH at baseline (n = 1067) were assigned to four WC status change groups (persistent normal WC, WC loss, WC gain, and persistent abdominal obesity). Over a 2-year follow-up, 103 (out of 1067) children had LVH. LVMI levels were the highest among the persistent abdominal obesity group (31.5 ± 3.8 g/m ^2.7), lower in the WC gain group (31.0 ± 3.6 g/m ^2.7) and the WC loss group (29.8 ± 3.7 g/m ^2.7), and lowest in the persistent normal WC group (29.1 ± 3.7 g/m ^2.7). Compared with children in the persistent normal WC group, the odds of LVH was highest in the persistent abdominal obesity group [odds ratio (OR) = 3.57, 95% confidence interval (CI): 2.18-5.83], followed by the WC gain group (OR = 2.85, 95% CI: 1.50-5.41). In contrast, the odds of LVH was not increased in the WC loss group (OR = 0.93, 95% CI: 0.21-4.07).

Conclusion: Although these findings highlight the importance of maintaining normal WC in childhood to reduce the odds of developing LVH, our data suggest the increased odds associated with abdominal obesity can be reversed by WC loss.