Effect of Lowering IOP in Glaucoma Suspects With HM (GSHM)

Effect of Medically Lowering Intraocular Pressure in Glaucoma Suspects With High Myopia: A Randomized Controlled Trial

Currently, whether and when intraocular pressure (IOP) lowering medication should be used in glaucoma suspects with high myopia (HM) is still a dilemma. Randomized trials are required to evaluate whether IOP lowering influences the incidence of glaucoma suspect progression in HM eyes.

Study Overview

• Status: Recruiting
• Conditions: High Myopia; Glaucoma, Suspect
• Intervention / Treatment: Drug: IOP lowering eye drops

Detailed Description

HM is associated with increased prevalence of glaucoma. However, accurate diagnosis of glaucoma in HM is a challenge. More and more viewpoints had been raised that HM eyes with optic disc head damage or/and visual field (VF) defects should been classified as glaucoma suspects.

IOP is the only modifiable parameter in glaucoma and glaucoma suspect patients. However, the decision to begin treatment to lower IOP in the glaucoma suspect patient is complex, especially for glaucoma suspects with HM. There are lack of guideline and consensus of treatment choices. Therefore, it is necessary to investigate the effect of medically IOP lowering on the progression of glaucoma suspects with HM.

• Study Type: Interventional
• Enrollment (Anticipated): 264
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Xiulan Zhang, MD, PhD; Phone Number: +86 13570166308; Email: zhangxl2@mail.sysu.edu.cn
• Study Contact Backup: Name: Fengbin Lin; Phone Number: +86 13826067110; Email: linfb52@163.com

Study Locations

• China
  • Guangdong
    • Guangzhou, Guangdong, China, 510060
      • Recruiting
      • Zhongshan Ophthalmic Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 33 years to 63 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. Aged between 35 and 65 years.
2. Diagnosed with high myopia (spherical equivalent ≤ -8.00 diopters or axial length ≥ 26.5 mm).
3. Diagnosed with glaucoma suspect, which cannot be explained by myopic macular changes, or other retinal and neurologic condition.
4. IOP ≥ 12 mmHg and ≤ 24mmHg on at least 2 visits, as measured by Goldmann applanation tonometry.
5. An open anterior chamber angle as based upon gonioscopy.
6. Best corrected visual acuity (BCVA) ≥ 6/12.

Exclusion Criteria:

1. Allergy to prostaglandins.
2. Advanced VF loss (MD worse than 16 dB) or a threat to fixation (sensitivity 10 dB or worse affecting either or both test points closest to the point of fixation in the upper hemifield and at either or both of the corresponding test points in the lower hemifield) in either eye.
3. Previous IOP-lowering surgery in the study eye (i.e. trabeculectomy, Ahmed glaucoma valve implantation, any laser trabeculoplasty).
4. Previous cataract surgery in the study eye.
5. Previous corneal refractive surgery in the study eye.
6. Clinically significant or progressive retinal disease such as proliferative diabetic retinopathy, retinal detachment, central retinal vein occlusion, or retinitis pigmentosa in the study eye.
7. Chronic, recurrent or severe inflammatory eye disease in the study eye (from screening), such as chronic or recurrent uveitis.
8. Obvious corneal and iris lesions, or severe cataracts interfering with fundus examinations, or monophtalmia.
9. Need for ocular surgery/laser or anticipated need for cataract surgery that would influence the ophthalmological parameters measured in this study during the study period.
10. Other serious systemic diseases (i.e. hypertension, heart disease, diabetes, or rheumatic immune system diseases).
11. Pregnant or nursing women.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Intervention arm; medical reduction of IOP by eyedrops	Drug: IOP lowering eye drops; Latanoprost 0.005% eye drops will be the first choice. If an IOP reduction of 20% is not achieved within three months, timolol 0.5% will be added as second medication. If an IOP reduction of 20% is then not achieved, alphagan 0.2% or alphagan-P 0.15% will be added. If an IOP reduction of 20% is then not achieved, the individual will be excluded from the study.; If necessary, latanoprost will be switched to other prostaglandin eye drops, alphagan (or alphagan-P) will be switched to brinzolamide 1% eye drops.; If necessary, latanoprost and timolol will be switched to Xalacom eye drops, timolol and alphagan will be switched to Combigan eye drops, timolol and brinzolamide will be switched to Azarga eye drops.; Once daily in the evening for prostaglandin eye drops, and twice daily for other eye drops.
No Intervention: control arm; follow up without medication

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
The number of subjects whose visual filed progressed during the follow up	36 months

Secondary Outcome Measures

Outcome Measure	Time Frame
The number of subjects whose optic nerve head morphology including the retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GCIPL) changed during the follow up	36 months
The number of subjects whose myopic maculopathy progressed during the follow up	36 months
The number of subjects whose visual function and quality of life changed during follow up	36 months

Collaborators and Investigators

• Sponsor: Sun Yat-sen University
• Investigators: Principal Investigator: Xiulan Zhang, MD, PhD, Sun Yat-sen University

Publications and helpful links

General Publications

• Leske MC, Hyman L, Hussein M, Heijl A, Bengtsson B. Comparison of glaucomatous progression between untreated patients with normal-tension glaucoma and patients with therapeutically reduced intraocular pressures. The effectiveness of intraocular pressure reduction in the treatment of normal-tension glaucoma. Am J Ophthalmol. 1999 May;127(5):625-6. No abstract available.
• Garway-Heath DF, Crabb DP, Bunce C, Lascaratos G, Amalfitano F, Anand N, Azuara-Blanco A, Bourne RR, Broadway DC, Cunliffe IA, Diamond JP, Fraser SG, Ho TA, Martin KR, McNaught AI, Negi A, Patel K, Russell RA, Shah A, Spry PG, Suzuki K, White ET, Wormald RP, Xing W, Zeyen TG. Latanoprost for open-angle glaucoma (UKGTS): a randomised, multicentre, placebo-controlled trial. Lancet. 2015 Apr 4;385(9975):1295-304. doi: 10.1016/S0140-6736(14)62111-5. Epub 2014 Dec 19. Erratum In: Lancet. 2015 Jul 11;386(9989):136.
• Leske MC, Heijl A, Hyman L, Bengtsson B. Early Manifest Glaucoma Trial: design and baseline data. Ophthalmology. 1999 Nov;106(11):2144-53. doi: 10.1016/s0161-6420(99)90497-9.
• Lin FB, Da Chen S, Song YH, Wang W, Jin L, Liu BQ, Liu YH, Chen ML, Gao K, Friedman DS, Jonas JB, Aung T, Lv L, Liu YZ, Zhang XL; GSHM study group. Effect of medically lowering intraocular pressure in glaucoma suspects with high myopia (GSHM study): study protocol for a randomized controlled trial. Trials. 2020 Sep 29;21(1):813. doi: 10.1186/s13063-020-04748-7.

Study record dates

Study Major Dates

• Study Start (Actual): April 17, 2020
• Primary Completion (Anticipated): October 1, 2024
• Study Completion (Anticipated): October 1, 2024

Study Registration Dates

• First Submitted: March 3, 2020
• First Submitted That Met QC Criteria: March 4, 2020
• First Posted (Actual): March 5, 2020

Study Record Updates

• Last Update Posted (Actual): May 6, 2022
• Last Update Submitted That Met QC Criteria: May 4, 2022
• Last Verified: May 1, 2022

More Information

Terms related to this study

• Keywords: Intraocular Pressure; Glaucoma, Suspect; High myopia
• Additional Relevant MeSH Terms: Eye Diseases; Refractive Errors; Glaucoma; Ocular Hypertension; Myopia; Pharmaceutical Solutions; Ophthalmic Solutions
• Other Study ID Numbers: 2020KYPJ026

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No