Abstract P285: Relationship Between Body Mass Index, Waist Measurement, Six-Minute Walk Performance and Whole-Body Strength in Adults With Cardiovascular Disease: Findings From the Lifestyle Heart Health Study

Abstract

Introduction: Cardiovascular disease (CVD) is the leading cause of death, killing 17.9 million people annually worldwide. Key risk factors include physical inactivity, overweight/obesity, high blood pressure, high cholesterol which worsen with age, and smoking and excessive alcohol intake. Six-minute walk (6MW) performance and whole-body muscle strength are both related to cardiovascular mortality and also worsen with age, particularly in the absence of physical activity. The aims of this study were to understand levels of cardiovascular risk and compliance to usual medical treatment (medication, lifestyle modifications) in a high socioeconomic Australian population, and to identify relationships between key risk factors, 6MW and muscle strength. A secondary aim was to help inform development of the Lifestyle Heart Health Education Program. Methods: This was a cross-sectional study of 473 people with CVD in Sydney. Class was classified based on the Australian socioeconomic index for areas. Conditions were defined according to Australian national guidelines. Medical history, body mass index (BMI), waist measurement, whole-body muscle strength and 6MW measurements were assessed. Simple linear and stepwise regressions were used to assess potential relationships. Results: Mean age of the cohort was 66.8±11.6; range 21-94 yrs; 68.5% female; socioeconomic index was deemed high. All participants had CVD, of which 25% were on aspirin. Hypertension was prevalent in 65% (38% on anti-hypertensives); 65% had dyslipidaemia (40% on a statin); 91% had a BMI over 26.0; and 85% of males and 80% of females had a waist measurement over gender-specific heart health recommendations. Less than 3% of the cohort smoked, and less than 10% consumed alcohol at a level deemed high-risk. Almost 20% of the cohort were at risk of CV mortality according to 6MW performance with scores less than 350 metres. Waist measurement, BMI, and blood pressure were the greatest risk factors across the cohort. Muscle strength (r=-0.34; r 2 =0.17; p<0.001) and 6MW performance (r=-0.37; r 2 =0.17; p<0.001) both decreased with age. BMI and age were the most significant predictors of 6MW (r=-0.45; r 2 =0.20; p=0.004) and whole-body strength (r=0.49; r 2 =0.24; p<0.001) in females; waist and age were the most significant predictors of 6MW (r=-0.38; r 2 =0.14; p=0.11) and whole-body strength (r=0.41; r 2 =0.17; p=0.04) in males. Conclusion: Whilst alcohol and smoking campaigns are working to reduce consumption of these harmful substances, low cardiorespiratory and muscular fitness and overweight/obesity remain highly prevalent. Population-level interventions such as the Lifestyle Heart Health Program that aim to reduce weight and waist and improve physical activity, walking ability and muscle strength are urgently needed to reduce cardiovascular risk and mortality.