Double product reserve is associated with waist circumference but not body mass index in overweight or obese individuals

Background Obesity is an independent risk factor for cardiovascular disease (CVD). Excessive accumulation of adipose tissue in the myocardium leads to structural and functional changes. Body mass index (BMI) is a parameter used to classify overweight and obesity, but it does not distinguish fat-free mass from fat mass and cannot be used to assess body fat distribution. Recent research suggests that abdominal obesity, as measured by waist circumference, is a risk factor for CVD independent of BMI. Purpose In this study, we aimed to investigate the relationship between double product (DP) reserve as a marker of cardiac workload and body composition in overweight and obese individuals. Methods One hundred and forty-one overweight or obese individuals aged 35-65 years (F:105, M:36, mean age=51.48±7.41/years) were included. Body composition (BMI, (mean±SD=35.61±23.31 kg/m2), waist circumference, body fat percentage, waist/hip ratio) was measured. DP was calculated according to the 6-minute walk test (6MWT), which is a submaximal exercise test to estimate myocardial work. It was calculated by multiplying heart rate (HR) by systolic blood pressure (SBP) at rest and after completion of the 6 MWT. DP reserve was calculated as the difference before and after 6MWT. Results DP reserve was not significantly different according to obesity classification (p=0.210, eta-squared=0.032, 95% CI=0.00-0.09) (Table1). DP reserve showed a weakly correlation with waist circumference (r=0.188, p=0.026). No significant relationship was observed between DP reserve and BMI, waist-to-hip ratio and body fat percentage (p>0.05). Conclusion The results of this study showed that cardiac workload estimated with DP reserve was associated with abdominal obesity but not with other body composition parameters. This finding can be interpreted as increased cardiac stress after submaximal exercise in subjects with increased waist circumference regardless of BMI or body fat percentage in overweight or obese subjects.