Blood pressure response to exercise in children and adolescents

Abstract

Blood pressure changes during exercise are part of the physiological response to physical activity. Exercise stress testing can detect an exaggerated blood pressure response in children and adolescent. It is applied for certain clinical conditions, but is also commonly used as part of the assessment of athletes. The interpretation of blood pressure values in response to exercise during childhood and adolescence requires appropriate reference data. We discuss the available reference values and their limitations with regard to device, exercise protocol and normalization. While the link between an exaggerated blood pressure response and cardiovascular events and mortality has been demonstrated for adults, the situation is less clear for children and adolescents. We discuss the existing evidence and propose that under certain circumstances it might be reasonable to have children and adolescents undergo exercise stress testing as a rather non-invasive procedure to add additional information with regard to their cardiovascular risk profile. Based on the existing data future studies are needed to extend our current knowledge on possible links between the presence of certain clinical conditions, the detectability of an exaggerated blood pressure response during childhood and adolescence and the risk of developing cardiovascular morbidity and mortality in later life.

Keywords: adolescents; arterial hypertension; blood pressure (BP); cardiovascular risk; children; exercise; stress test.

FIGURE 1

Feedback loop as the physiological response to physical activity. The central command initiates muscle activity via somatomotor neurons. Simultaneously the vascular, heart and respiratory systems are activated, in part through the increasing sympathetic activity. This leads to a surge in cardiac output and peripheral vascular resistance, which in turn raises (systolic) blood pressure. The change in hemodynamics triggers the baroreceptor reflex, while the metabolic activity of muscle exertion is sensed by chemoreceptors. Figure created with BioRender.com.

FIGURE 2

Possible implementation of exercise stress testing to improve cardiovascular (CV) health screening in children and adolescents. Measurement of resting blood pressure (BP) identifies children and adolescents with elevated BP [i.e., pathologic reading above the 95th percentile according to guidelines (49)], who can be subsequently referred to medical follow up and potential treatment. However, subjects with a normal resting BP (i.e., below the 95th percentile) but presenting with additional CV risk factors (e.g., obesity/adiposity, abnormal lipid status, abnormal glucose tolerance or overt diabetes, a family history of CV disease and/or a severe lack of physical activity) may profit from further evaluation by undergoing exercise stress testing. An exaggerated BP response during exercise stress testing would warrant closer medical follow up. Children and adolescents with normal BP response to exercise as well as those with no other CV risk factors do not need increased medical attention. When performing exercise stress testing one must be aware of the limitations described in this article with regard to device, protocol and reference values. Figure created with BioRender.com.