Genetic and Risk Factors in Exfoliation Glaucoma Patients

Patients & examinations In this prospective non-randomised cohort study, the investigators enrolled patients with exfoliation glaucoma at the Ophthalmology Department of the Skaraborg's Hospital, Skövde, and Sahlgrenska University Hospital, Gothenburg, from 1st January, 2014, to 31st December, 2017. All patients were followed-up for three years ± three months. Informed consent was obtained from all patients. The study protocol was granted ethical approval by the University of Gothenburg (DN:119-12). The study was performed in accordance with the tenets of the Declaration of Helsinki.

At the recruiting visit, an ophthalmic nurse checked the visual acuity of patients with a Snellen's chart and performed a visual field test. Humphrey Field Analysis was performed using the software threshold 24-2. Subsequently, an ophthalmologist measured the intracoular pressure (IOP) with a Goldmann applanation tonometer and performed slit-lamp biomicroscopy, including gonioscopy. Pupils were then dilated with 2.5% phenylephrine and 0.5% tropicamide. After 20 min, the presence of exfoliation was confirmed, and the optic nerve was assessed using a 90-D lens. Subsequently, the central corneal thickness (CCT) was measured using an ultrasound device. The average value of seven measurements was automatically calculated. At the end of the visit, blood samples were collected. The number of medicines was registered as the number of compounds and not the number of bottles used.

Inclusion criteria

• A diagnosis of exfoliation glaucoma based on the criteria established by the European Glaucoma Society Terminology and Guidelines for Glaucoma, i.e., an untreated IOP of ≥21 mmHg, an open anterior chamber angle, glaucomatous visual field defects (at least two repeatable Humphrey 24-2 tests), glaucomatous optic nerve damage, and the presence of exfoliation material.
• Patients must performed at least five reliable visual field tests during the 3-year follow-up, with reliability defined as false positives ≤15%, false negatives ≤20%, and/or fixation losses ≤30%.
• Age ≤85 years at the recruiting visit.

Exclusion criteria

• A diagnosis of advanced glaucoma defined as mean deviation (MD) ≥18 decibel (dB) and/or visual field index (VFI) ≤40% because of 'floor effects,' in which further loss of visual field defects can no longer be detected.
• History of glaucoma surgery other than uneventful cataract surgery or selective laser trabeculoplasty (SLT).
• Other eye diseases (central venous occlusion, retinal detachment, etc.) that could affect the visual fields during the 3-year follow-up.