Neovascular age-related macular degeneration (nAMD) represents one of the leading causes of blindness in both developed and developing countries. This thesis examines inequalities and variations in visual outcomes for people being treated for nAMD, the reasons behind any variation, and how this variation relates to self-reported quality of life.
nAMD began to be treated via intraocular injections with anti-vascular endothelial growth factors (anti-VEGF) after 2006. This thesis drew on the landmark trials that first established the safety and efficacy of anti-VEGF therapy for nAMD.
Using a systematic review, this thesis then investigated whether there were factors that could be identified from the literature that influenced how effective anti-VEGF therapy is in reducing visual loss in patients with nAMD. This thesis highlights the importance of being able to identify modifiable factors, such as number of anti-VEGF injections received, that could lead to better visual outcomes for these patients.
This thesis then goes on to examine levels of variation in visual outcome in nAMD nationally in the UK, as well as further investigating any influencing factors that could not be identified in the systematic review. This was done using a large real-world dataset of over 26,00 patients from seven hospitals. This highlighted significant levels of variation, but struggled to identify definitively further influencing factors, such as ethnicity or social deprivation. This could be because there genuinely was not an associated relationship between these factors and visual outcomes, but certainly in the case of ethnicity, it is particularly apparent that there was an overwhelmingly white population, so there may have not been enough ethnic variation to detect any effect of ethnicity.
This thesis then investigates the link between visual acuity and quality of life, in a prospective study of patients from a teaching hospital in York. However, due to a much-reduced sample size, partly due to the COVID-19 pandemic, this thesis was unable to meaningfully link the two outcomes.
The focus of this thesis was that of identifying and understanding variation in patients being treated for nAMD, within a wider picture of variation and inequality in healthcare in general. It showed variation in visual outcomes, but apart from visual acuity at baseline and number of injections, it was unable to identify other influencing factors. It is therefore concluded that further work with larger sample sizes needs to be undertaken to definitively address the overall aims of this thesis. Along with this, further attention needs to be given to the role of intersectionality of possible influencing factors in visual outcomes. Some of the methodology used in this thesis also need to reconsidered, such as if further prospective work is done, considering using telephone follow-up. There also needs to be consideration of taking into account the effect of the better seeing eye on quality of life.
