Exercise positively impacts global longitudinal strain (GLS) in women at risk of developing cardiovascular disease

Abstract

Abstract Funding Acknowledgements Type of funding sources: Other. Main funding source(s): Australian Government Research Training Scholarship. Background/Introduction Cardiovascular (CV) disease accounts for one in three deaths in women globally each year, with hypertension (HTN) and type 2 diabetes (T2DM) recognised as primary modifiable risk factors for its development. Global longitudinal strain (GLS) is a highly sensitive CV imaging measure that detects early signs of myocardial dysfunction prior to clinical abnormalities arising, and is a strong prognostic indicator for future CV dysfunction and mortality. However, the effect of exercise on GLS in women with HTN or T2DM is unclear. Purpose This study aimed to determine if exercise positively impacts GLS in women with HTN or T2DM. Changes in peak aerobic fitness (VO2peak) were also explored. Methods A randomised crossover trial was performed at our university between August 2021-December 2022. Fifteen women (aged 64.1 ± 4.7) diagnosed with HTN (n=12) and T2DM (n=3) participated. Participants completed an 8-week exercise and 8-week control period, separated by a washout period of 21.6 ± 14.2 weeks. Comprehensive 2D and 3D resting echocardiography and exercising testing were performed pre-and-post each arm to measure GLS (%) and VO2peak (ml/kg/min). The exercise intervention consisted of three supervised aerobic exercise sessions per week for eight consecutive weeks, performed at a moderate intensity. Nine participants were required to provide 80% power to detect an absolute mean difference in GLS of 1.7 between groups (10% relative change in GLS from a baseline GLS of −17%), with an alpha of 0.05. A linear mixed effect model was used to compare outcomes between (exercise vs control) and within (pre- vs. post-intervention) groups for GLS and VO2peak. All participants who completed at least one arm of the trial were included in analyses. Results Nine participants completed the crossover, with four completing the control arm only, and two completing the exercise arm only. Exercise adherence was high (86.6%). GLS (%) increased significantly following exercise (−16.8 ± 1.5 to −18.4 ± 1.8; p = <0.001), but not control (−17.2 ± 2.0 to −16.9 ± 1.4; p = 0.585). Similarly, a significantly improvement in VO2peak (ml/kg/min) was observed following exercise (18.0 ± 2.1 to 19.2 ± 2.6; p = <0.001), but not control (17.5 ± 2.7 to 17.2 ± 2.7; p = 0.269). There was a significant between-group difference for both GLS (p = <0.001) and VO2peak (p = 0.011) (figure 1). Conclusion(s) Aerobic exercise positively impacts GLS in women at risk of developing CV disease. Due to its high sensitivity, GLS could be used to measure the effectiveness of aerobic exercise programs in populations at risk of developing CV disease, before changes in traditional clinical measures are expected to occur.