center dot PURPOSE: Hypertension (HTN) has been associated with open-angle glaucoma (OAG), but whether elevated blood pressure (BP) alone is associated with OAG known. Whether stage 1 hypertension, as per the American College of Cardiology/American Heart Asso-ciation (ACC/AHA) BP guidelines, increases the risk the disease is uncertain. center dot DESIGN: Retrospective, observational, cohort study. center dot METHODS: A total of 360,330 subjects who were years of age and not taking antihypertensive or antiglau-coma drugs at the time of health examinations between January 1, 2002, and December 31, 2003, were included. Subjects were categorized based on their untreated into normal BP (systolic BP [SBP] < 120 and diastolic BP [DBP] < 80 mm Hg; n = 104,304), elevated (SBP 120-129 and DBP < 80 mm Hg; n = 33,139), stage 1 HTN (SBP 130-139 or DBP 80-89 mm n = 122,534), or stage 2 HTN (SBP >140 or >90mm Hg; n = 100,353). Cox regression analysis performed to calculate hazard ratios (HR) of OAG center dot RESULTS: The mean age of the subjects was 51.17 +/- 8.97 years, and 56.2% were male. During a follow-up period of 11.76 +/- 1.37 years, 12,841 jects (3.56%) were diagnosed with OAG. Multivariable-adjusted HRs (95% CIs) were 1.056 (0.985-1.132) elevated BP, 1.101(1.050-1.155) for stage 1 HTN, 1.114(1.060-1.170) for stage 2 HTN with normal the reference. center dot CONCLUSIONS: The risk for OAG becomes greater with increases in untreated BP. Stage 1 HTN per 2017 ACC/AHA BP guidelines is a significant risk factor for OAG. (Am J Ophthalmol 2023;252: 111-120. 2023 Elsevier Inc. All rights reserved.)