Effect of high myopia on 24-hour intraocular pressure in patients with primary open-angle glaucoma

摘要

Background As intraocular pressure (lOP) and lOP fluctuation are known risk factors for glaucoma,it is important to understand the effects of high myopia on these ocular parameters.The aim of this study was to investigate if primary open-angle glaucoma (POAG) patients with high myopia exhibit higher lOP and greater lOP fluctuations at resting conditions over 24 hours.@@Methods We designed a prospective control clinical study.Eighty-two eyes of 82 high-tension Chinese POAG patients only on prostaglandin analogue locally were divided into 3 groups according to various myopic grades (<-6.0 D,n=27 and between -0.76 and -5.99 D,n=33) or without myopia (-0.75 to 0.75 D,n=22).Single time lOP at 10 am,mean corrected 24-hour lOP,mean corrected night lOP,24-hour lOP fluctuation and lOPs of 10 am,2 pm,6 pm,10 pm,2 am,6 am and 8 am were measured.@@Results The lOP was higher in POAG patients with high myopia over those POAG alone in three ways:the elevated lOP value was 0.65 mmHg measured in single time lOP at 10 am,0.84 mmHg in mean corrected 24-hour lOP,0.97 mmHg in mean corrected night lOP.The 24-hour lOP fluctuation was lower in the two myopia groups than in non-myopia group.Further,using repeated measurement analysis of variance,there was no statistical significance among groups regarding the lOPs at the seven time points (P=0.77) and there was no interaction between groups and time points (P=0.71),but the difference of lOPs at the seven time points in same group was statistically significant (P=0.01).@@Conclusion High-tension POAG patients with high myopia,even on pharmacological glaucoma therapy,still have higher lOp,but 24-hour lOP fluctuation at resting conditions was lower in these patients.