What Change in Body Mass Index Is Required to Improve Cardiovascular Outcomes in Childhood and Adolescent Obesity through Lifestyle Interventions: A Meta-Regression

Abstract

Background: Using meta-regression, this article aims at establishing the minimum change in BMI-standard deviation score (SDS) needed to improve lipid profiles and blood pressure in children and adolescents with obesity, to aid future trials and guidelines. Methods: Studies with participants involved in lifestyle interventions, aged 4-19 years, with a diagnosis of obesity according to defined BMI thresholds, were considered for inclusion in a large systematic review. Interventions had to report pre-and postintervention (or mean change in) BMI-SDS, plus either systolic blood pressure (SBP), high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, and/or triglycerides (TGs). Random-effects meta-regression quantified the relationship between mean change in BMI-SDS and mean change in cardiovascular outcomes. Results: Seventy-one papers reported various cardiovascular measurements and mean change in BMI-SDS. Fifty-four, 59, 46, and 54 studies were analyzed, reporting a change in SBP, HDL, LDL, and TG, respectively. Reduction in mean BMI-SDS was significantly related to improvements in SBP, LDL, TG, and HDL (p < 0.05); BMI-SDS reductions of 1, 1.2, and 0.7 ensured a mean reduction of SBP, LDL, and TG, respectively, although an equivalent value for HDL improvement was indeterminate. Conclusion: Reductions in mean BMI-SDS of >1, >1.2, or >0.7 are likely to reduce SBP, LDL, and TG, respectively. Further studies are needed to clarify the optimal duration, intensity, and setting for interventions. Consistency is required regarding derived BMI values to facilitate future systematic reviews and meta-analyses.

Impact of Lifestyle Intervention Programs for Children and Adolescents with Overweight or Obesity on Body Weight and Selected Cardiometabolic Factors—A Systematic Review

“…Ho et al [ 54 ] showed that lifestyle interventions reduced BMI by an average of 1.25 kg/m 2 (BMI z-score: −0.1), and a significant reduction in LDL-C and TG levels and blood pressure in children and adolescents with overweight or obesity aged ≤18 years. Similarly, an analysis of data from 71 studies assessing the effect of weight reduction on the parameters of the lipid profile and blood pressure showed that a decrease in BMI z-score by > 1.2 is a likely factor in reducing the level of LDL-C and by > 0.7 for TG and by > 1 for SBP [ 60 ]. Other researchers indicate a reduction in cardiometabolic risk with a decrease in BMI z-score by ≥ 0.25 in adolescents with obesity, and greater health benefits can be achieved with a decrease in BMI z-score by a minimum of 0.5 [ 61 ].…”

Impact of short-term change of adiposity on risk of high blood pressure in children: Results from a follow-up study in China

“…A reduction of only 0.86%-3.59% of BMI could lead to beneficial effect on HBP in our study. However, a recent meta-analysis of 54 lifestyle intervention studies in pediatric populations showed that reduction of >1 mean BMI SDS is related to improved SBP [7]. Considering the difference of race, and age in different studies, it is hard to compare or make a final quantification of the minimum favorable BMI reduction for metabolic health.…”

“…The association between obesity and blood pressure (BP) levels or hypertension has been demonstrated in numerous cross-sectional studies [4][5][6]. Also, intervention studies against obesity showed that weight management will additionally benefit BP profile [7]. But in a natural life course, it remains unclear whether the change of general or abdominal fat accumulation status without intervention would impact the risk of HBP in childhood.…”

“…A previous weight management study among overweight children show that the reduction of just 5% of body mass index (BMI) is associated with improvements in lipid profiles and insulin sensitivity in six months [8], and a meta-analysis of lifestyle intervention studies showed that BMI standard deviation score (SDS) reduction of >1 SDS is associated with better BP profiles [7]. However, in a natural life course without intervention, for obese children the minimum range of adiposity reduction proposed to reduce the HBP risk is not known now.…”

Changes in Body Composition and Cardiometabolic Risk Factors in Relation to the Reduction in Body Mass Index in Adolescents with Obesity

“…A recently published meta-regression study [19] concluded that a minimum 0.6 decrease in BMI-SDS is imperative in order to attain any improvement in fat mass. Furthermore, a systematic review with meta-analysis [20] and several meta-regression studies [21,22] concluded that reductions in BMI-SDS are likely to improve cardiovascular outcome in childhood and adolescent obesity; nevertheless, at present, they are unable to recommend a de nite value of BMI-SDS reduction indispensable to improve markers of metabolic health. In other words, the reduction in BMI-SDS required to improve both body composition and the pro le of cardiovascular risk factors by means of lifestyle interventions has not yet been fully established.…”