Background/aims To evaluate the relationship over time between intraocular pressure (IOP) and the rate of macula whole image vessel density (wiVD) loss and whole image ganglion cell complex (wiGCC) thinning in glaucoma
Methods From 62 patients in the Diagnostic Innovations in Glaucoma Study, 59 Primary open-angle glaucoma and 27 glaucoma suspect eyes with mean follow-up of 3.2 years were followed. Optical coherence tomography angiography (OCT-A)-based vessel density and OCT-based structural thickness of the same 6×6 mm GCC scan slab were evaluated. Univariable and multivariable linear mixed models were performed for all eyes and also a subset of them in which peak IOP <18 mm Hg to investigate the effect of IOP parameters on the rate of wiVD and wiGCC change.
Results The mean baseline visual field mean deviation (95% CI) was −3.3 dB (−4.4 to –2.1). Higher mean IOP (−0.07%/year per 1 mm Hg (−0.14 to –0.01), p=0.033), peak IOP (−0.07%/year per 1 mm Hg (−0.13 to –0.02), p=0.004) and IOP fluctuation (IOP SD) (−0.17%/year per 1 mm Hg (−0.32 to 0.02), p=0.026) were associated with faster macular vessel density loss. Faster wiGCC thinning was associated with higher mean IOP (−0.05 µm/year per 1 mm Hg (−0.10 to –0.01), p=0.015), peak IOP (−0.05 µm/year per 1 mm Hg (−0.08 to –0.02), p=0.003) and IOP fluctuation (−0.12 µm/year per 1 mm Hg (−0.22 to –0.01), p=0.032). In eyes with peak <18 mm Hg, faster wiVD progression was associated with higher mean IOP (p=0.042). Faster wiGCC progression was associated with higher mean IOP in these eyes (p=0.025).
Conclusion IOP metrics were associated with faster rates of overall macular microvascular loss and also in the eyes with peak IOP <18 mm Hg. Future studies are needed to examine whether additional IOP lowering reduces the rate of microvascular loss in patients with glaucoma.
Trial registration number NCT00221897.
- Intraocular pressure
Data availability statement
Data are available upon reasonable request. The datasets generated and/or analysed during the current study are available from the corresponding author on reasonable request.
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.
GM and SM contributed equally.
Presented at The paper was presented as a poster presentation at the American Glaucoma Society (AGS) annual meeting in Nashville, Tennessee, 2022.
Contributors GM and SM involved in design and conduct of study. GM, TN, SM, EM, VM, J-HW, KHD and AK contributed to data collection. GM, SM, TN and RNW contributed to analysis and interpretation of data. GM, SM and RNW contributed to writing. GM, TN, SM, EM, VM, J-HW, KHD and AK contributed to critical revision. GM, TN, SM, EM, VM, J-HW, KHD, AK and RNW contributed to approval of the manuscript. RNW had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. RNW is the study guarantor.
Funding National Institutes of Health/National Eye Institute Grants R01EY029058, R01EY034148; UC Tobacco Related Disease Research Program (T31IP1511); an unrestricted grant from Research to Prevent Blindness (New York, New York, USA) and participant retention incentive grants in the form of glaucoma medication at no cost from Novartis/Alcon Laboratories, Allergan, Akorn and Pfizer. The sponsor or funding organisations had no role in the design or conduct of this research.
Competing interests RNW: Financial support—National Eye Institute; Research instruments: Carl Zeiss Meditec, Centervue, Heidelberg Engineering, Konan, Optovue, Topcon; Consultant—Abbvie, Aerie Pharmaceuticals, Allergan, Amydis, Eyenovia, Implandata, Ioptic, Nicox, Topcon.
Provenance and peer review Not commissioned; externally peer reviewed.
Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.