Blood pressure change with age in salt-sensitive teenagers

Objective: To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing. Methods: Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years. Results: After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P < 0.01; 12.2%±12.0% vs. 2.5%±4.4%, P < 0.001, respectively). There was a similar trend for diastolic blood pressure (8.4±6.4 mmHg vs. 3.7±6.4 mmHg, P = 0.052; 13.2%± 10.6 % vs. 6.8%±10.1%, P = 0.053, respectively). Conclusions: Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.