Calculations of mean ocular perfusion pressure before and after exercise are conditioned by the formula used

Abstract

AbstractPurpose: Blood pressure is a key parameter associated with ocular health and glaucoma. Additionally, brachial blood pressure serves to calculate ocular perfusion pressure. The main aim was to evaluate differences between the most used formulas to calculate mean brachial arterial blood pressure and the effects that physical exercise may have in this parameter.Methods: Fifteen physically active, healthy subjects (9 male 6 female, 24.07 ± 3.65 years) voluntarily performed a 15‐minute protocol consisting of combined exercise including, mobility, bodyweight exercises, running, dynamic stretching, and three sets of barbell back squat at low intensities. The formulas compared were 1) diastolic blood pressure (DBP) + 1/3 * (systolic blood pressure [SBP] ‐ DBP); 2) DBP + 0.412 * (SBP – DBP); 3) DBP + (0.333 + (0.0012 * heart rate)) * (SBP ‐ DBP); 4) DBP + (25.361 + 0.047 * heart rate + 0.163 * DBP) * (SBP ‐ DBP); 5) (SBP * DBP) ^ 1/2. A two‐way analysis of variance evaluated the effect of the exercise and the formula used to calculate the mean blood pressure.Results: Significant effects of the exercise (F(1, 14) = 88.66, p < 0.001, η2 = 0.86), formula used (F(1.06, 14.86) = 250.23, p < 0.001, η2 = 0.95), and their interaction (F(1.37, 19.11) = 54.75, p < 0.001, η2 = 0.80) were observed in the resulting values. The post‐hoc results showed significant differences between most of the formulas both preexercise and postexercise.Conclusions: The results presented suggest that caution should be applied when using indirect formulas to estimate mean brachial arterial pressure. Future research should objectively evaluate mean blood pressure with a direct method to find the most reliable formula. Meanwhile, this study is published to raise awareness on the importance of choosing one or other methods when aiming to estimate with formulas physiological parameters related to ocular health.