Hemodynamic responses to exercise in obese children and adolescents before and after overweight reduction

Effect of bariatric surgery on blood pressure response to exercise in a severely obese population

BACKGROUND

Exaggerated blood pressure response to exercise is a cardiovascular risk factor associated to higher morbidity and mortality. Severely obese patients have an increased risk of exercise-induced hypertension (EIH). We aimed to assess the blood pressure response to exercise in patients with severe obesity who underwent bariatric surgery as well as the main determinants of this response.

METHODS

We used data from the ACTIVE clinical trial, in which 60 severely obese patients who underwent bariatric surgery were enrolled. Anthropometric measurements, abdominal and mid-thigh computed tomography scans and maximal exercise testing were performed before bariatric surgery, as well as 3 and 6 months post-surgery. EIH was defined as a maximal SBP ≥210 mmHg for men and ≥190 mmHg for women.

RESULTS

At baseline, 62% of patients had EIH. At 6 months, we observed an EIH resolution rate of 39%. The main determinant of EIH resolution was sex. Actually, patients with EIH resolution were mostly women without resting hypertension and a lower amount of visceral adipose tissue.

CONCLUSION

These results suggest that bariatric surgery is efficient to resolve EIH, particularly in women with initially a better anthropometric profile.

The Impact of the Weight Status on Cardiovascular Parameters Related to Physical Effort in Young Athletes

Excess weight leads to an impaired cardiovascular response to physical exertion even at a young age. Sports training during youth promotes cardiovascular adaptations. The aim of the study is to verify the impact of weight status on cardiovascular parameters related to physical effort in young people who engage in competitive sports. A retrospective study was conducted on 8307 young athletes (5578 males and 2729 females) aged 6–18 years (mean age 13.9 ± 2.2 years). The data concerning graded exercise tests of young athletes in normal weight and overweight were compared. Approximately, 13.4% of the sample had excess weight. Young overweight athletes show a higher resting heart rate as well as systolic and diastolic pressure than young normal weight athletes. Excess weight condition leads to a reduction in the duration of the graded exercise test, reaching higher blood pressure values at the end of the test compared to those with normal weight. After four min from the end of the test, heart rate and systolic/diastolic blood pressure remained higher in the young overweight athletes. Excess weight affects cardiovascular parameters both at rest and in response to physical exertion during youth; however, competitive sport seems to be able to keep these parameters within the normal range even in young overweight athletes.

Cardiovascular disease risk in healthy children and its association with body mass index: systematic review and meta-analysis

OBJECTIVES

To describe the association and its magnitude between body mass index category, sex, and cardiovascular disease risk parameters in school aged children in highly developed countries.

DESIGN

Systematic review and meta-analysis. Quality of included studies assessed by an adapted version of the Cochrane Collaboration's risk of bias assessment tool. Results of included studies in meta-analysis were pooled and analysed by Review Manager version 5.1.

DATA SOURCES

Embase, PubMed, EBSCOHost's cumulative index to nursing and allied health literature, and the Web of Science databases for papers published between January 2000 and December 2011.

REVIEW METHODS

Healthy children aged 5 to 15 in highly developed countries enrolled in studies done after 1990 and using prospective or retrospective cohort, cross sectional, case-control, or randomised clinical trial designs in school, outpatient, or community settings. Included studies had to report an objective measure of weight and at least one prespecified risk parameter for cardiovascular disease.

RESULTS

We included 63 studies of 49 220 children. Studies reported a worsening of risk parameters for cardiovascular disease in overweight and obese participants. Compared with normal weight children, systolic blood pressure was higher by 4.54 mm Hg (99% confidence interval 2.44 to 6.64; n=12 169, eight studies) in overweight children, and by 7.49 mm Hg (3.36 to 11.62; n=8074, 15 studies) in obese children. We found similar associations between groups in diastolic and 24 h ambulatory systolic blood pressure. Obesity adversely affected concentrations of all blood lipids; total cholesterol and triglycerides were 0.15 mmol/L (0.04 to 0.25, n=5072) and 0.26 mmol/L (0.13 to 0.39, n=5138) higher in obese children, respectively. Fasting insulin and insulin resistance were significantly higher in obese participants but not in overweight participants. Obese children had a significant increase in left ventricular mass of 19.12 g (12.66 to 25.59, n=223), compared with normal weight children.

CONCLUSION

Having a body mass index outside the normal range significantly worsens risk parameters for cardiovascular disease in school aged children. This effect, already substantial in overweight children, increases in obesity and could be larger than previously thought. There is a need to establish whether acceptable parameter cut-off levels not considering weight are a valid measure of risk in modern children and whether methods used in their study and reporting should be standardised.