Intraocular pressure fluctuation and the risk of glaucomatous damage deterioration: a Meta-analysis

AIM: To systematically review whether the increased fluctuation of intraocular pressure(IOP) is a risk factor for open angle glaucoma(OAG) progression. METHODS: Scientific studies relevant to IOP fluctuation and glaucoma progression were retrieved from MEDLINE,EMBASE and CENTRAL databases, and were listed as references in this paper. The hazard ratio(HR) was calculated by using fixed or random-effects models according to the heterogeneity of included studies. RESULTS: Individual data for 2211 eyes of 2637 OAG patients in fourteen prospective studies were included in this Meta-analysis. All studies were longitudinal clinical studies with follow-up period ranging from 3 to 8.5 y. The combined HR was 1.23(95%CI 1.04-1.46, P=0.02) for the association between IOP fluctuation and glaucoma onset or progression with the evidence of heterogeneity(P<0.1).Subgroup analyses with different types of IOP fluctuation were also evaluated. Results indicated that the summary HR was 0.98(95%CI 0.78-1.24) in short-term IOP fluctuation group, which showed no statistical significance with heterogeneity, whereas, the combined HR was 1.43(95%CI1.13-1.82, P=0.003) in long-term IOP fluctuation group without homogeneity. Sensitivity analysis further showed that the pooled HR was 1.10(95%CI 1.03-1.18, P=0.004) for long-term IOP fluctuation and visual function progression with homogeneity among studies(P=0.3). CONCLUSION: Long-term IOP fluctuation can be a risk factor for glaucoma progression based on the presentedevidence. Thus, controlling the swing of IOP is crucial for glaucoma or glaucoma suspecting patients.