Sodium-Potassium Blood Pressure Trial in Children
Sodium-Potassium Blood Pressure Trial in Children
To examine the effects of nutritional intervention on the rate of rise of blood pressure in
 late childhood and early adolescence.
BACKGROUND:

 Since 1970, children and adolescents with hypertension have been detected with increasing
 frequency. Many of them were thought to have primary or essential hypertension and it
 remained unclear how they should be managed. Additionally, since tracking of blood pressure
 occurred even in early life, it was believed that youngsters with blood pressures
 persistently in the upper deciles for age were at increased risk for later hypertension. No
 clinical trials had been performed in this age group to examine the effects of
 non-pharmacologic or drug therapy in lowering blood pressure. The trial was one of the first
 attempts to examine the effects of a nutritional intervention on the rate of rise of blood
 pressure in late childhood and early adolescence.

 DESIGN NARRATIVE:

 Randomized, partial-blind. After 19,542 fifth to eighth grade students were screened, 210
 (105 boys and 105 girls) from the upper 15 percentiles of blood pressure distribution were
 randomly assigned to one of three groups: low sodium diet (70 mmol sodium intake per day),
 potassium chloride supplementation (normal diet plus 1 mmol/kg potassium chloride per day),
 and placebo (normal diet plus placebo capsule). Capsules for the potassium chloride and
 placebo groups were administered in a double blind protocol. Blood pressure was measured
 every three months for three years. The effect of the intervention was determined by
 comparing the rate of rise (slope) of blood pressure among the groups using a
 random-coefficient growth curve model.
Children in grades 5 through 8 whose systolic blood pressure was greater than or equal to
 120 mm Hg on two visits.