Stress and salt sensitivity in childhood hypertension

The pressure response to sodium is heterogeneous among individuals with normal blood pressure and in hypertensives. Nevertheless, sodium restriction is typically recommended for everyone with hypertension. As reviewed here, categorization of an individual as salt sensitive has important prognostic and therapeutic implications. Determination of salt sensitivity is typically accomplished by assessment of the pressure response to administration of an oral or intravenous sodium load. We discuss an alternative way to administer a sodium load through stress exposure. Animal and human studies have demonstrated signifi cant sodium retention during and after stress which in effect generates positive sodium balance and thus delivers a sodium load. Individuals demonstrating this response develop a volume-dependent elevation of the blood pressure. Similar to fi ndings in salt-sensitive populations, target organ changes have also been associated with impaired sodium handling during stress. This pattern of sodium retention in response to stress has been improved or reversed after treatment with antihypertensive medications that block the renin-angiotensin-aldosterone system. The variability of the pressure response to dietary sodium intake and to stress should be considered in our strategies to prevent and control hypertension.