Background: Improper sodium handling during stress (i.e. sodium retention) increases the risk of cardiovascular events, such as hypertension. Efficient identification of these retainers,therefore, is important in clinical practice. We developed a protocol to identify these patients that can be implemented into Standard of Care.
Methods: The protocol was tested using 19 patients (aged 10-19) in an outpatient clinic. Urine samples and blood pressure were obtained prior to and following a normal physician visit to establish baseline and stress values, respectively.
Results: 44% (8/19) of subjects were sodium retainers, retaining 3.2 mEq/hr, or approximately 73.5 mg of sodium with a systolic blood pressure (BP) increase of 5.4 mm Hg during the visit. 7/8 of these retainers were hypertensive. Excretors filtered 6.2 mEq/hr (141.6 mg) of sodium and showed a small decrease in systolic BP by 0.7 mm Hg.
Conclusions: Our results indicate that the normal stress of a physician visit can induce pressure natriuresis in patients and that this protocol could serve as a clinically efficient method for identifying sodium retainers at increased risk for cardiovascular disease.