Obesity Pillars Roundtable: Obesity and South Asians

Interrupting sitting acutely attenuates cardiometabolic risk markers in South Asian adults living with overweight and obesity

PURPOSE

This study examined the acute effects of interrupting sitting with light-intensity walking on postprandial cardiometabolic risk markers in South Asian adults.

METHODS

South Asians with overweight/obesity (n = 19; body mass index [BMI] > 23 kg·m-2) and normal-weight (n = 8; BMI 18.0-22.9 kg·m-2) aged 48.8 ± 5.6 years completed two, 5-h conditions: (1) prolonged sitting (SIT), and (2) interrupted sitting with 5-min bouts of light-intensity walking every 30-min (INT-SIT). Blood samples and resting expired air samples were collected throughout each condition. Statistical analyses were completed using linear mixed models.

RESULTS

In participants with overweight/obesity, postprandial glucose, triglycerides (TAG) and metabolic load index (MLI) over time were lower, whereas resting substrate utilisation and resting energy expenditure (REE) were higher, in INT-SIT than SIT (all p ≤ 0.05). Compared with SIT (0.18 [95% CI 0.13, 0.22] kcal.min-1), INT-SIT (0.23 [95% CI 0.18, 0.27] kcal.min-1) increased postprandial REE iAUC in participants with overweight/obesity (p = 0.04, d = 0.51). Postprandial TAG concentrations over time were lower in INT-SIT versus SIT (p = 0.01, d = 30) in normal-weight participants, with no differences in any other outcomes for this sample group.

CONCLUSION

These findings suggest that interrupting sitting with 5-min bouts of light walking every 30-min acutely attenuates cardiometabolic risk markers among South Asians living with overweight/obesity, whereas limited effects may be seen in individuals with normal-weight.

System inflammation response index: a novel inflammatory indicator to predict all-cause and cardiovascular disease mortality in the obese population

AIM

This study aims to investigate the relationship between two novel inflammatory markers, namely, the Systemic Inflammatory Response Index (SIRI) and the Systemic Immune Inflammatory Index (SII), as well as the all-cause and cardiovascular disease (CVD) mortality in the obese population.

MATERIALS AND METHODS

We conducted a prospective cohort study based on the data of 13,026 obese adults (age ≥ 18 years) from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2014 and followed until December 2019. SIRI was calculated by the formula: (neutrophil count × monocyte count) / lymphocyte count, while that of SII was: (platelet count × neutrophil count)/lymphocyte count. The association of SIRI and SII with all-cause and CVD mortality was evaluated using Cox regression. In addition, the nomogram was performed to predict 10-year survival probability.

RESULTS

During a median follow-up of 137 months, 1959 and 553 all-cause and CVD deaths were recorded, respectively. Spearman correlation analysis indicated that SIRI and SII were unrelated to almost all baseline characteristics (r < 0.15). Multivariate Cox regression models displayed that each standard deviation (SD) increase in SIRI was associated with a 16% (HR 1.16; 95% CI 1.09-1.24) and 22% (HR 1.22; 95% CI 1.10-1.36) increase in the risk of all-cause and CVD mortality, respectively. Likewise, every SD increase in SII was correlated with a 9% (HR 1.09; 95% CI 1.02-1.16) and 14% (HR 1.14; 95% CI 1.04-1.26) increase in the risk of all-cause and CVD mortality, respectively. The predictive value of SIRI for all-cause and CVD mortality (AUC = 0.601 and 0.624) exceeded that of SII (AUC = 0.528 and 0.539). Moreover, the nomogram displayed a substantial predictive value for 10-year survival (AUC = 0.847) with sensitivity and specificity exceeding 75%.

CONCLUSIONS

In the obese population, SIRI and SII are independent risk factors for all-cause and CVD mortality. Notably, the predictive ability of SIRI for both all-cause and CVD mortality significantly outperforms that of SII, suggesting that SIRI is a more valuable marker of inflammation.