Early Laser Treatment for Diabetic Eye Disease in China : A Pilot Randomized Trial

Study Overview
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Brief Summary
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To compare immediate laser pan-retinal photocoagulation (PRP) treatment of severe or very severe non proliferative diabetic retinopathy (NPDR) stage versus deferral of treatment until the appearance of any proliferative diabetic retinopathy (PDR) in rural and urban patients in China. Interview data from some patients and survey data from ophthalmologists in the study hospitals will help determine acceptability of early treatment, and how to overcome barriers to increased use of this option.

Detailed Description
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China now has the world's largest number of diabetic persons. Population studies show that only 10% of Chinese rural-dwellers with DR receive therapy. The current standard approach to treatment of DR often requires patients to return for multiple examinations over years, before they reach trial-proven criteria for treatment. This long process is ill-suited to support good compliance with care in low-resource settings. Our recent published review suggests that earlier PRP treatment, which could reduce the burden of compliance, may be clinically effective and cost effective, but the current evidence base is insufficient to make a firm recommendation.

Official Title
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Early Laser Treatment for Diabetic Eye Disease in China: The PEARL Pilot Randomized Trial

Conditions
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Diabetic Retinopathy

Intervention / Treatment
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* Procedure: Pan-retinal photocoagulation laser treatment


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adults aged >= 18 years with untreated DR at severe or very severe NPDR stage in either one or both eyes, according to the clinical opinion of the investigator. Sufficiently clear ocular media to allow visualization of the retina and retinal photography in either eye. Capable of giving informed consent. Exclusion Criteria: DR at later stage of retinopathy than severe or very severe (eg, two or more of the 4-2-1 criteria are met) NPDR in either eye, but a patient may be enrolled if one eye has severe or very severe NPDR and the fellow eye has PRP-treated PDR and has been stable after treatment. Clinically significant macular edema in either eye. Dense cataracts or other media opacity preventing visualization of the retina in the eye. History of previous surgical or laser treatment for DR or other retinal conditions in a study eye, including history of anti-VEGF or corticosteroid injection or focal laser for DME within 6 months, or any history of scleral buckle, vitrectomy or other retinal detachment repair. History of other retinal vascular disorders including CRVO, CRAO, BRVO, BRAO in the study eye. Previous cataract or glaucoma surgery is specifically allowed if performed ≥ 6 weeks prior to enrollment. Pregnancy. Severe renal insufficiency treated with hemodialysis treatment, kidney transplant, pancreatic transplant, and intensive insulin therapy initiated within 4 months. Nystagmus, unable to cooperate with laser treatment.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Early Intervention<br>pan-retinal photocoagulation laser treatment applied to the study eye within 2-4 weeks. | Procedure: Pan-retinal photocoagulation laser treatment<br>* PRP initially consists of 1200 - 1600 burns given over 2-3 sessions and separated by2-3weeks by 532-argon laser machine.<br>* Other names: PRP laser treatment;|
| Active Comparator: Standard Care<br>pan-retinal photocoagulation laser treatment deferred until the onset of any PDR. | Procedure: Pan-retinal photocoagulation laser treatment<br>* PRP initially consists of 1200 - 1600 burns given over 2-3 sessions and separated by2-3weeks by 532-argon laser machine.<br>* Other names: PRP laser treatment;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Proportion of eyes progressing to any degree of PDR | The diagnosis of PDR will be made by detecting either active new vessels in the optic nerve head or elsewhere in the retina as determined by fundus photography read by a masked investigator or preretinal/vitreous haemorrhage at any time during the 12 month follow-up period. | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Proportion of early versus standard treated eyes with: Loss of >= 10 and of 15 ETDRS letters |  | 1 year | 
| Mean change in best corrected visual acuity from baseline to week 52. |  | 1 year | 
| Proportion of early versus standard treated eyes with: retinal detachment |  | 1 year | 
| Proportion of early versus standard treated eyes with: increase of diabetic macular edema per Optical Coherence Tomography |  | 1 year | 
| Sensitivity & specificity of the diagnosis of any degree of PDR among study ophthalmologists | Study ophthalmologists will also ascertain the primary outcome measure (diagnosis of any degree of PDR) on the basis of slit-lamp biomicropscopy fundus examination with a contact lens and indirect ophthalmoscopy. We will compare the sensitivity & specificity of the diagnosis of any degree of PDR among study ophthalmologists with the gold stander (diagnosis provided by graders according to the fundus photos.) | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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diabetic retinopathy, Pan-retinal photocoagulation, proliferative, non-proliferative