ASCEND-Eye: Rationale, design and baseline characteristics for a sub-study of the ASCEND randomised trial, exploring the effects of aspirin and omega-3 fatty acids on diabetic retinopathy and age-related macular degeneration

Emily Sammons; Louise Bowman; William Stevens; Georgina Buck; Karl Wallendszus; Imen Hammami; Sarah Parish; Jane Armitage; ASCEND Collaborative Group

doi:10.1016/j.conctc.2023.101184

ASCEND-Eye: Rationale, design and baseline characteristics for a sub-study of the ASCEND randomised trial, exploring the effects of aspirin and omega-3 fatty acids on diabetic retinopathy and age-related macular degeneration

Contemp Clin Trials Commun. 2023 Jul 5:35:101184. doi: 10.1016/j.conctc.2023.101184. eCollection 2023 Oct.

Authors

Emily Sammons¹, Louise Bowman¹, William Stevens², Georgina Buck², Karl Wallendszus², Imen Hammami², Sarah Parish², Jane Armitage¹; ASCEND Collaborative Group

Affiliations

¹ Medical Research Council Population Health Research Unit, Clinical Trial Service Unit & Epidemiological Studies Unit, University of Oxford, Nuffield Department of Population Health, Richard Doll Building, Old Road Campus, Roosevelt Drive, Oxford, OX3 7LF, UK.
² Medical Research Council Population Health Research Unit, Clinical Trial Service Unit & Epidemiological Studies Unit, University of Oxford, Nuffield Department of Population Health, Big Data Institute, Old Road Campus, Roosevelt Drive, Oxford, OX3 7LF, UK.

Abstract

Background: Aspirin and omega-3 fatty acids (FAs) have potential disease-modifying roles in diabetic retinopathy (DR) and age-related macular degeneration (AMD), but randomized evidence of these effects is limited. We present the rationale and baseline characteristics of ASCEND-Eye, a sub-study of the double-blind, 2x2 factorial design, randomized placebo-controlled ASCEND (A Study of Cardiovascular Events iN Diabetes) trial of 100 mg aspirin daily and, separately, 1g omega-3 FAs daily for the primary prevention of serious cardiovascular events, in 15,480 British adults, aged 40 years or older with diabetes.

Methods: Eye events will be derived from three sources: 1) participant follow-up questionnaires from ASCEND, 2) electronic NHS Diabetic Eye Screening Programme (DESP) data and 3) responses to the National Eye Institute's Visual Function Questionnaire-25 (NEI-VFQ-25) sent to a subset of participants after the main trial ended. Analytic cohorts and outcomes relevant to these data sources are described. The primary outcome is referable diabetic eye disease, a secondary outcome is incident AMD events.

Results: Participant-reported events were ascertained for the full cohort of randomized individuals who were followed up over 7.4 years in ASCEND (n = 15,480). Linked DESP data were available for 48% of those (n = 7360), and 57% completed the NEI-VFQ-25 (n = 8839). The baseline characteristics of these three cohorts are presented.

Discussion: Establishing the risks and benefits of drugs commonly taken by people with diabetes, the elderly, or both, and finding new treatments for DR and AMD is important. ASCEND-Eye provides the opportunity to evaluate the effect of aspirin and, separately, omega-3 FAs for both conditions.

Study registration: Eudract No. 2004-000991-15; Multicentre Research Ethics Committee Ref No. 03/8/087; ClinicalTrials.gov No. NCT00135226; ISRCTN No. ISRCTN60635500.

Keywords: Age-related macular degeneration; Aspirin; Diabetic retinopathy; Omega-3 fatty acids; Randomized trial.

Associated data

ClinicalTrials.gov/NCT00135226

Abstract

Associated data

Grants and funding