TY - JOUR
T1 - The Low-pressure Glaucoma Treatment Study (LoGTS)
T2 - Study design and baseline characteristics of enrolled patients
AU - Krupin, Theodore
AU - Liebmann, Jeffrey M.
AU - Greenfield, David S.
AU - Rosenberg, Lisa F.
AU - Ritch, Robert
AU - Yang, John W.
N1 - Funding Information:
The LoGTS organization consists of 13 clinical centers. The study protocol and informed consent were approved by Institutional Review Boards at all participating centers. A Data Center for masked computer analysis of the visual fields is located at University Eye Specialists, Chicago, and a Data Center for the optic disc photographs is located at University Eye Specialists, Chicago, and the Hamilton Glaucoma Center of the University of California, San Diego. The randomization assignment list is maintained and masked study medications are provided directly to the clinical centers by Fountain Valley Pharmacy (Fountain Valley, CA). Optic disc, visual field, and coordinating centers are masked from each other. Data on treatment effects and the randomization code are not provided during the course of the study. The study is supported by an unrestricted grant from Allergan, Inc. (Irvine, CA) to the Low-Pressure Glaucoma Study Group and the Chicago Center for Vision Research (Chicago, IL).
Funding Information:
Supported by an unrestricted grant to the Low-Pressure Glaucoma Study Group from Allergan, Inc., Irvine, California, and the Chicago Center for Vision Research, Chicago, Illinois.
Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 2005/3
Y1 - 2005/3
N2 - Objective: The Low-Pressure Glaucoma Treatment Study (LoGTS) seeks to evaluate visual field stability in low-pressure glaucoma patients randomized to intraocular pressure reduction in both eyes with topical twice daily brimonidine tartrate 0.2% versus twice daily timolol maleate 0.5%. This article describes the LoGTS design and presents baseline characteristics of the subjects. Design: Randomized, multicenter, double-masked clinical trial. Participants: Low-pressure glaucoma patients 30 years of age or older were identified. Exclusion criteria included an untreated pressure of more than 21 mmHg, advanced visual field loss, and contraindications to study medications. Interventions: Randomization of both eyes to double-masked monotherapy with brimonidine or timolol. Follow-up visits included Humphrey 24-2 full-threshold perimetry, tonometry every 4 months, and annual optic disc photography. Main Outcome Measure: Progression of visual field loss. Results: One hundred ninety patients were randomized between 1998 and 2000. Mean age (±standard deviation) was 64.9±10.7 years. Women comprised 59.5% of the patients. Fifty-three patients (27.9%) had unilateral field loss. The 137 patients with bilateral field loss were older than those with unilateral field loss: 65.7 versus 62.3 years of age (P<0.05). Mean untreated diurnal intraocular pressures were similar between the eyes of the bilateral patients (mean, 15.5 mmHg in both eyes) and unilateral patients (mean, 16.0 mmHg in field loss vs. 15.6 mmHg in fellow eyes). Visual field mean deviation for all eyes was -5.4±4.7 decibels. Central corneal thickness in 168 phakic patients was 543 ± 35 μm (range, 435-655 μm); thickness was less than 500 μm in 15 eyes and was more than 600 μm in 11 eyes. Mean vertical cup-to-disc ratio for all eyes was 0.67±0.15. Unilateral field loss patients had a larger cup-to-disc ratio in the field loss eye (0.75±0.12) than the fellow eye with a normal field (0.60±0.17, P<0.0001). Disc hemorrhage was present at baseline in 29 patients (32 eyes). Conclusions: The LoGTS was successfully able to recruit and enroll patients with open-angle glaucoma and statistically normal intraocular pressure into a longitudinal, prospective clinical trial comparing 2 different glaucoma medications. Baseline characteristics of note were a preponderance of females, unilateral field loss in 27.9% of participants, and frequent optic disc hemorrhage. Central corneal thickness had a normal distribution and did not account for false low-pressure measurements in LoGTS patients.
AB - Objective: The Low-Pressure Glaucoma Treatment Study (LoGTS) seeks to evaluate visual field stability in low-pressure glaucoma patients randomized to intraocular pressure reduction in both eyes with topical twice daily brimonidine tartrate 0.2% versus twice daily timolol maleate 0.5%. This article describes the LoGTS design and presents baseline characteristics of the subjects. Design: Randomized, multicenter, double-masked clinical trial. Participants: Low-pressure glaucoma patients 30 years of age or older were identified. Exclusion criteria included an untreated pressure of more than 21 mmHg, advanced visual field loss, and contraindications to study medications. Interventions: Randomization of both eyes to double-masked monotherapy with brimonidine or timolol. Follow-up visits included Humphrey 24-2 full-threshold perimetry, tonometry every 4 months, and annual optic disc photography. Main Outcome Measure: Progression of visual field loss. Results: One hundred ninety patients were randomized between 1998 and 2000. Mean age (±standard deviation) was 64.9±10.7 years. Women comprised 59.5% of the patients. Fifty-three patients (27.9%) had unilateral field loss. The 137 patients with bilateral field loss were older than those with unilateral field loss: 65.7 versus 62.3 years of age (P<0.05). Mean untreated diurnal intraocular pressures were similar between the eyes of the bilateral patients (mean, 15.5 mmHg in both eyes) and unilateral patients (mean, 16.0 mmHg in field loss vs. 15.6 mmHg in fellow eyes). Visual field mean deviation for all eyes was -5.4±4.7 decibels. Central corneal thickness in 168 phakic patients was 543 ± 35 μm (range, 435-655 μm); thickness was less than 500 μm in 15 eyes and was more than 600 μm in 11 eyes. Mean vertical cup-to-disc ratio for all eyes was 0.67±0.15. Unilateral field loss patients had a larger cup-to-disc ratio in the field loss eye (0.75±0.12) than the fellow eye with a normal field (0.60±0.17, P<0.0001). Disc hemorrhage was present at baseline in 29 patients (32 eyes). Conclusions: The LoGTS was successfully able to recruit and enroll patients with open-angle glaucoma and statistically normal intraocular pressure into a longitudinal, prospective clinical trial comparing 2 different glaucoma medications. Baseline characteristics of note were a preponderance of females, unilateral field loss in 27.9% of participants, and frequent optic disc hemorrhage. Central corneal thickness had a normal distribution and did not account for false low-pressure measurements in LoGTS patients.
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U2 - 10.1016/j.ophtha.2004.10.034
DO - 10.1016/j.ophtha.2004.10.034
M3 - Article
C2 - 15745762
AN - SCOPUS:14644435009
VL - 112
SP - 376
EP - 385
JO - Ophthalmology
JF - Ophthalmology
SN - 0161-6420
IS - 3
ER -