Collaborative Initial Glaucoma Treatment Study: a summary of results to date

PURPOSE OF REVIEW: This review summarizes the key findings from the Collaborative Initial Glaucoma Treatment Study (CIGTS), which was designed to evaluate whether medical therapy or trabeculectomy is the better initial treatment for patients with open-angle glaucoma (OAG). In addition to examining effects on visual field progression, intraocular pressure control, and visual acuity, the study also examined the effects of medical and surgical treatments on quality of life. RECENT FINDINGS: The 4+-year interim outcomes noted no significant difference in visual field loss between the medically and surgically treated patients. Patients assigned to trabeculectomy had lower intraocular pressures, but demonstrated a greater risk for significant loss of visual acuity and a threefold increased rate of cataract progression. Most quality-of-life measurements were similar in the two treatment arms, except local eye symptoms, which were reported more frequently by the surgically treated patients. SUMMARY: Results from CIGTS do not support altering current treatment practices in the initial management of patients with primary open-angle glaucoma.     

Quality of life in newly diagnosed glaucoma patients : The Collaborative Initial Glaucoma Treatment Study

OBJECTIVE: The Collaborative Initial Glaucoma Treatment Study (CIGTS) was designed to determine whether patients with newly diagnosed open-angle glaucoma are better treated initially by medicine or immediate filtering surgery. This paper describes the quality-of-life (QOL) measurement approach, instruments included, and the CIGTS participants' QOL findings at the time of diagnosis. DESIGN: Baseline results from a randomized, controlled clinical trial. PARTICIPANTS: Six hundred seven patients from 14 clinical centers were enrolled. INTERVENTION: Patients randomized to initial medication received a stepped medical regimen (n = 307). Those randomized to initial surgery underwent a trabeculectomy (n = 300). The baseline interview was conducted before treatment initiation. All baseline and posttreatment QOL assessments were conducted by telephone from a centralized interviewing center. MAIN OUTCOME MEASURES: The primary outcome measure described in this paper was QOL. The QOL instrument is multidimensional and incorporates both disease-specific and generic measures, including the Visual Activities Questionnaire, Sickness Impact Profile, and a Symptom and Health Problem CHECKLIST: RESULTS: The correlations between QOL measures and clinical outcomes were in the expected direction, but relatively weak. At initial diagnosis, difficulty with bright lights and with light and dark adaptation were the most frequently reported symptoms related to visual function, whereas visual distortion was the most bothersome. Approximately half of the patients reported at least some worry or concern about the possibility of blindness. Within the Visual Activities Questionnaire, higher scores on the Peripheral Vision subscale were associated with more field loss (P < 0.01). In regression analyses controlling for sociodemographics and nonocular comorbidities, increased visual field loss was significantly associated with higher dysfunction among five disease-specific QOL measures (P < 0.05). CONCLUSIONS: Newly diagnosed glaucoma patients reported experiencing some visual function symptoms at the time of diagnosis that would not be intuitively expected based on clinical testing. Some discussion about the association between clinical presentation and worry about blindness may reduce unnecessary concern. These results provide the basis for long-term comparisons of the QOL effects of initial medical and surgical treatment for open-angle glaucoma.     

Interim clinical outcomes in the Collaborative Initial Glaucoma Treatment Study comparing initial treatment randomized to medications or surgery.

PURPOSE: To report interim outcome data, using all available follow-up through 5 years after treatment initiation, in the Collaborative Initial Glaucoma Treatment Study (CIGTS). DESIGN: Randomized clinical trial. PARTICIPANTS: Six hundred seven newly diagnosed glaucoma patients. METHODS: In a randomized clinical trial, 607 patients with newly diagnosed open-angle glaucoma were initially treated with either medication or trabeculectomy (with or without 5-fluorouracil). After treatment onset and early follow-up, patients were evaluated clinically at 6-month intervals. In addition, quality of life telephone interviews were conducted at similar frequency to the clinical visits. Patients in both arms of CIGTS were treated aggressively in an effort to reduce intraocular pressure (IOP) to a level at or below a predetermined target pressure specific for each individual eye. Visual field (VF) scores were analyzed by time-specific comparisons and by repeated measures models. MAIN OUTCOME MEASURES: VF loss was the primary outcome variable in CIGTS. Secondary outcomes of visual acuity (VA), IOP, and cataract were also studied. RESULTS: On the basis of completed follow-up through 4 years and partially completed through 5 years, VF loss did not differ significantly by initial treatment. Over the entire period of follow-up, surgical patients had a greater risk of substantial VA loss compared with medical patients. However, by 4 years after treatment, the average VA in the two groups was about equal. Over the course of follow-up, IOP in the medicine group has averaged 17 to 18 mmHg, whereas that in the surgery group averaged 14 to 15 mmHg. The rate of cataract requiring removal was greater in the surgically treated group. CONCLUSIONS: Both initial medical or initial surgical therapy result in about the same VF outcome after up to 5 years of follow-up. VA loss was greater in the surgery group, but the differences between groups seem to be converging as follow-up continues. When aggressive treatment aimed at substantial reduction in IOP from baseline is used, loss of VF can be seen to be minimal in general. Because 4 to 5 years of follow-up in a chronic disease is not adequate to draw treatment conclusions, these interim CIGTS outcomes do not support altering current treatment approaches to open-angle glaucoma.     

The Collaborative Initial Glaucoma Treatment Study: study design, methods, and baseline characteristics of enrolled patients

OBJECTIVE: The Collaborative Initial Glaucoma Treatment Study (CIGTS) is a randomized, controlled clinical trial designed to determine whether patients with newly diagnosed open-angle glaucoma (primary, pigmentary, or pseudoexfoliative) are better treated by initial treatment with medications or by immediate filtration surgery. DESIGN: Randomized, controlled clinical trial. PARTICIPANTS: A total of 607 patients with open-angle glaucoma were enrolled. INTERVENTION: Patients randomized to initial medications (n=307) received a stepped regimen of medications to lower intraocular pressure. Those randomized to initial surgery (n=300) underwent trabeculectomy to lower intraocular pressure. MAIN OUTCOME MEASURES: Progression in visual field loss constitutes the study's primary outcome variable. Secondary outcomes include health-related quality of life, visual acuity, and intraocular pressure. RESULTS: Randomized assignment resulted in a balanced distribution between treatment groups for most demographic and clinical measures assessed at enrollment. More males than females were enrolled (55% were males), and a substantial percentage (38.1 %) of enrollees were blacks. Most enrollees (90.6%) were diagnosed with primary open-angle glaucoma; the remainder had either pseudoexfoliative (4.8%) or pigmentary (4.6%) forms of open-angle glaucoma. CONCLUSIONS: Follow-up of this well-characterized group of patients should provide well-rounded guidance, based on both traditional ophthalmic measures and patients' perspectives on their health-related quality of life, on how best to initially treat open-angle glaucoma.     

慢性闭角型青光眼视野损害的特点

目的　为了了解早中期慢性闭角型青光眼 (chronicangleclosureglaucoma ,CACG)的静态视野损害特点。对象与方法　对象为MD≤ 15dB的慢性青光眼患者 81例 81只眼 ,其中CACG 2 7例 2 7只眼 ,正常眼压性青光眼 19例 19只眼 ,和原发性开角型青光眼 3 5例 3 5只眼。采用Octopus10 1视野计G2程序 ,将视野内 5 9个静点划分为 9个区和中央 1个点 ,通过图中各点的值 ,分别计算每只眼的每个点、区的MD ;再将视野以 0°～ 180°为界 ,分成上下两个半侧视野 ,分别计算和比较上方和下方半侧视野的MD和LV ;最后对中央 9个点 (6°范围 )进行受累情况的判断 ,并进行CACG、POAG和NTG三组组内和组间的比较。结果　CACG组的中央区MD比POAG NTG组要小 (Z =-2 0 69,P =0 0 3 9) ,其余各区和中心点差异无显著性 (Z =-0 0 6～ 1 72 1,P =0 0 9～ 0 95 2 ) ;CACG和POAG上方半侧视野的MD明显比下方的MD要大 (P =0 0 2 4和 0 0 10 ) ,而NTG的上下方视野MD差异无显著性 (P =0 0 77)。CACG、NTG和POAG中央 6°视野的受累率分别是 2 5 9%、5 7 9%和 5 1 9% (P =0 0 40 )。结论　CACG上方半侧视野比下方受损明显 ,与POAG/NTG视野改变模式有所不同的是 ,中央视野比较不易受损。     

Measuring visual field progression in the Early Manifest Glaucoma Trial

AIMS: The Early Manifest Glaucoma Trial (EMGT) (316 eligible eyes) has used a new set of criteria to define visual field progression in glaucoma. This paper provides estimates of the amount of visual field worsening required to reach the EMGT definition of definite perimetric progression. METHODS: In the 148 eyes that reached definite progression, we first determined changes between baseline and the time of definite EMGT progression, both for mean deviation (MD) and for number of highly (p < 0.5%) significantly depressed test points in pattern deviation probability maps. Second, we studied whether such changes depended on baseline MD, intraocular pressure (IOP), age and time to progression, all of which are factors that affect the rate of field progression. RESULTS: In eyes reaching progression, the mean change in MD from baseline was -1.93 dB (SE +/- 0.20) and the mean change in number of significant points was +4.85 (SE +/- 0.35). These changes did not show linear dependency on baseline MD, IOP or time to progression. CONCLUSIONS: The average amount of field deterioration needed to reach EMGT visual field progression has been measured and expressed in more conventional units (i.e. a loss of about - 2dB in MD and an increase in about five highly significant points). These estimates will facilitate the clinical interpretation of the results of EMGT.     

The Collaborative Initial Glaucoma Treatment Study: interim quality of life findings after initial medical or surgical treatment of glaucoma.

OBJECTIVE: To present interim quality of life (QOL) findings in the Collaborative Initial Glaucoma Treatment Study (CIGTS) using all available follow-up through 5 years from treatment initiation. DESIGN: Randomized controlled clinical trial. PARTICIPANTS: Six hundred seven newly diagnosed patients with open-angle glaucoma from 14 clinical centers. INTERVENTION: Patients were randomly assigned to either initial medical therapy or initial trabeculectomy. After treatment initiation and early follow-up, patients received clinical and QOL evaluations at 6-month intervals. QOL assessments were administered by telephone at a centralized interviewing center. MAIN OUTCOME MEASURES: The CIGTS collected comprehensive QOL information that included both generic and vision-specific QOL measures. This article focuses on initial treatment group differences related to symptom reporting, as measured by a Symptom and Health Problem Checklist, and changes in daily visual functioning, as measured by the Visual Activities Questionnaire (VAQ). RESULTS: Across both treatment groups, there was an overall decline in the percent of participants reporting symptoms over time. Of 43 possible symptoms, 12 symptoms were reported with greater frequency by the surgically treated group and 7 symptoms more frequently by the medically-treated group. The surgical patients reported more total Symptom Impact Glaucoma (P = 0.005) and, in particular, more bother related to local eye symptoms. Very few treatment group differences were noted in visual functioning, although surgical patients reported more problems with activities related to their visual acuity (P = 0.024). The percentage of patients across treatment groups reporting worry about blindness was 50% at baseline but declined to approximately 25% over time. CONCLUSIONS: Overall, the QOL impact reported by the two treatment groups as measured by instruments used in this study is remarkably similar, with relatively few significant study group differences observed after up to 5 years of follow-up in the CIGTS. When significant differences in visual function have been detected using the VAQ, they are consistent with the clinical outcomes. To date, the most persistent QOL finding is the increased impact of local eye symptoms reported by the surgical group compared with the medical group. Although no changes are recommended in the treatment of newly diagnosed glaucoma patients at the time of this interim report, further follow-up will allow for more definitive answers to the QOL impact of these two treatment approaches.