Which blood pressure measurement, systolic or diastolic, better predicts future hypertension in normotensive young adults?

<jats:p>The impact of age‐related differences in blood pressure (<jats:styled-content style="fixed-case">BP</jats:styled-content>) components on new‐onset hypertension is not known. A follow‐up examination of 93 303 normotensive individuals (mean age 41.1 years) who underwent a health checkup in 2005 was conducted every year for 8 years. The primary end point was new‐onset hypertension (<jats:styled-content style="fixed-case">systolic BP [SBP]</jats:styled-content>/diastolic BP [<jats:styled-content style="fixed-case">DBP]</jats:styled-content> ≥140/90 mm Hg and/or the initiation of antihypertensive medications with self‐reported hypertension). During the mean 4.9 years of follow‐up, 14 590 subjects developed hypertension. The impact of <jats:styled-content style="fixed-case">DBP</jats:styled-content> on the risk of developing hypertension compared with optimal <jats:styled-content style="fixed-case">BP</jats:styled-content> (<jats:styled-content style="fixed-case">SBP</jats:styled-content> <120 mm Hg and <jats:styled-content style="fixed-case">DBP</jats:styled-content> <80 mm Hg) was significantly greater than that of <jats:styled-content style="fixed-case">SBP</jats:styled-content> in subjects younger than 50 years (hazard ratios, 17.5 for isolated diastolic high‐normal vs 10.5 for isolated systolic high‐normal [<jats:italic>P</jats:italic><.001]; 8.0 for isolated diastolic normal vs 4.1 for isolated systolic normal [<jats:italic>P</jats:italic><.001]). Among the subjects 50 years and older, the corresponding effects of <jats:styled-content style="fixed-case">DBP</jats:styled-content> and <jats:styled-content style="fixed-case">SBP</jats:styled-content> were similar. Regarding the risk of new‐onset hypertension, high <jats:styled-content style="fixed-case">DBP</jats:styled-content> is more important than <jats:styled-content style="fixed-case">SBP</jats:styled-content> in younger adults (<50 years) with normal or high‐normal <jats:styled-content style="fixed-case">BP</jats:styled-content>.</jats:p>