Selective laser trabeculoplasty versus drops for newly diagnosed ocular hypertension and glaucoma: the LiGHT RCT.

Background: Newly diagnosed open-angle glaucoma (OAG) and ocular hypertension (OHT) are habitually treated with intraocular pressure (IOP)-lowering eyedrops. Selective laser trabeculoplasty (SLT) is a safe alternative to drops and is rarely used as first-line treatment.

Objectives: To compare health-related quality of life (HRQoL) in newly diagnosed, treatment-naive patients with OAG or OHT, treated with two treatment pathways: topical IOP-lowering medication from the outset (Medicine-1st) or primary SLT followed by topical medications as required (Laser-1st). We also compared the clinical effectiveness and cost-effectiveness of the two pathways.

Design: A 36-month pragmatic, unmasked, multicentre randomised controlled trial.

Settings: Six collaborating specialist glaucoma clinics across the UK.

Participants: Newly diagnosed patients with OAG or OHT in one or both eyes who were aged ≥ 18 years and able to provide informed consent and read and understand English. Patients needed to qualify for treatment, be able to perform a reliable visual field (VF) test and have visual acuity of at least 6 out of 36 in the study eye. Patients with VF loss mean deviation worse than -12 dB in the better eye or -15 dB in the worse eye were excluded. Patients were also excluded if they had congenital, early childhood or secondary glaucoma or ocular comorbidities; if they had any previous ocular surgery except phacoemulsification, at least 1 year prior to recruitment or any active treatment for ophthalmic conditions; if they were pregnant; or if they were unable to use topical medical therapy or had contraindications to SLT.

Interventions: SLT according to a predefined protocol compared with IOP-lowering eyedrops, as per national guidelines.

Main Outcome Measures: The primary outcome was HRQoL at 3 years [as measured using the EuroQol-5 Dimensions, five-level version (EQ-5D-5L) questionnaire]. Secondary outcomes were cost and cost-effectiveness, disease-specific HRQoL, clinical effectiveness and safety.

Results: Of the 718 patients enrolled, 356 were randomised to Laser-1st (initial SLT followed by routine medical treatment) and 362 to Medicine-1st (routine medical treatment only). A total of 652 (91%) patients returned the primary outcome questionnaire at 36 months. The EQ-5D-5L score was not significantly different between the two arms [adjusted mean difference (Laser-1st - Medicine-1st) 0.01, 95% confidence interval (CI) -0.01 to 0.03;  = 0.23] at 36 months. Over 36 months, the proportion of visits at which IOP was within the target range was higher in the Laser-1st arm (93.0%, 95% CI 91.9% to 94.0%) than in the Medicine-1st arm (91.3%, 95% CI 89.9% to 92.5%), with IOP-lowering glaucoma surgery required in 0 and 11 patients, respectively. There was a 97% probability of Laser-1st being more cost-effective than Medicine-1st for the NHS, at a willingness to pay for a quality-adjusted life-year of £20,000, with a reduction in ophthalmology costs of £458 per patient (95% of bootstrap iterations between -£585 and -£345).

Limitation: An unmasked design, although a limitation, was essential to capture any treatment effects on patients' perception. The EQ-5D-5L questionnaire is a generic tool used in multiple settings and may not have been the most sensitive tool to investigate HRQoL.

Conclusions: Compared with medication, SLT provided a stable, drop-free IOP control to 74.2% of patients for at least 3 years, with a reduced need for surgery, lower cost and comparable HRQoL. Based on the evidence, SLT seems to be the most cost-effective first-line treatment option for OAG and OHT, also providing better clinical outcomes.

Future Work: Longitudinal research into the clinical efficacy of SLT as a first-line treatment will specify the long-term differences of disease progression, treatment intensity and ocular surgery rates between the two pathways.

Trial Registration: Current Controlled Trials ISRCTN32038223.

Funding: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in ; Vol. 23, No. 31. See the NIHR Journals Library website for further project information.