Treatment burden and adherence in adults receiving long-term anti-VEGF intravitreal injections for retinal disease: a qualitative evidence synthesis protocol.

introductionRetinal diseases such as neovascular age-related macular degeneration and diabetic macular oedema are leading causes of irreversible vision loss and require intravitreal anti-vascular endothelial growth factor (VEGF) injections over many years. Repeated treatment imposes physical, psychological, social and financial burdens and is associated with reduced adherence and poorer real-world outcomes. Existing research is largely quantitative and does not explain, from patients' perspectives, why people persist with, struggle against or discontinue burdensome treatment. This review will identify, appraise and synthesise qualitative studies to understand the burden of long-term anti-VEGF therapy, how it shapes adherence and the implications for patient-centred nursing care, shared decision-making and injection-service design. METHODS AND ANALYSIS: This protocol is reported in accordance with Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P); the completed synthesis will be reported following Enhancing Transparency in Reporting the Synthesis of Qualitative Research. We will use Thomas and Harden's three-stage thematic synthesis and the Population, Phenomenon of Interest, Context and Study design framework. Eligible studies are primary qualitative studies and independently extractable qualitative components of mixed-methods studies involving adults (≥18 years) receiving long-term anti-VEGF therapy for retinal disease, irrespective of publication language. Initial searches of nine databases (PubMed, Embase, CINAHL, PsycINFO, Web of Science, Scopus, CNKI, Wanfang Data and SinoMed) were conducted from inception between 31 May and 2 June 2026 and will be updated before completion of the review. Citation tracking and thesis-repository searches will supplement the database searches. Two reviewers will independently screen records, extract data and appraise quality using the Joanna Briggs Institute checklist, with disagreements resolved by a third reviewer. Confidence in each finding will be assessed using Grading of Recommendations Assessment, Development and Evaluation-Confidence in the Evidence from Reviews of Qualitative research. ETHICS AND DISSEMINATION: Ethical approval is not required because the review uses published data. Six to eight patients, with up to two family advisers, will help interpret preliminary themes and develop a plain-language summary. Findings will be disseminated through peer-reviewed publication and conference presentation. PROSPERO REGISTRATION NUMBER: CRD420261405614.