The arterial stiffness and pulse pressure are predictors of intraocular pressure in a middle-aged population

The vascular theory posits that glaucoma is associated to ocular blood flow alterations. However, there is uncertainty regarding the association of arterial stiffness index (ASI) and pulse pressure (PP) to intraocular pressure (IOP). This study investigates the relationship between ASI and PP, and IOP, using the UK Biobank population. Among 89,930 participants of the UK Biobank population, ASI and PP were assessed, and their correlations with IOP were estimated using multiple linear and logistic regressions adjusted for age, sex, BMI, diabetes, dyslipidemia, mean blood pressure, heart rate, tobacco smoking status, previous CV diseases and antihypertensive therapy. Youden indices were determined for ASI at a value of 9.41 m/s and for PP at 49.18 mmHg to determine IOP > 21mmHg. After adjustment for all covariates, ASI > 9.41 m/s was significantly correlated with IOP levels, B = 0.054 [0.031; 0.076] and with IOP > 21 mmHg, OR = 1.057 [1.004-1.113]. PP > 49.18 mmHg was significantly associated with IOP levels, B = 0.378 [0.345; 0.401] and with IOP > 21 mmHg, OR = 1.558 [1.474-1.648]. Similar results were observed when considering ASI and PP at continuous levels. When considering participants with IOP < 21 mmHg (N = 83,079), ASI > 9.41 m/s and PP > 49.18 mmHg were significantly associated with IOP levels, B = 0.015 [0.008; 0.021], B = 0.286 [0.266; 0.306], respectively. We demonstrated that increased ASI and PP levels are associated with increased IOP. These findings provide new insight into the vascular theory between IOP and ASI.