Age-related macular degeneration (AMD) is aetiologically linked to immunological ageing and dysfunction. One aspect of this is the altered neutrophil-tolymphocyte ratio (NLR), which in other domains have been associated with inflammation and angiogenesis, and therefore investigated in patients with AMD in several papers. In this systematic review and meta-analysis, we summarize findings in patients with AMD in relation to NLR, both qualitatively and quantitatively. We searched PubMed/MEDLINE, EMBASE, Web of Science, and the Cochrane Central and identified six studies from where we extracted data on 1178 individuals (777 patients with AMD and 401 healthy controls). Patients with AMD had a higher NLR (weighted mean difference: 0.37, CI 95% 0.08 to 0.66, p = 0.013) when compared to healthy controls. In subgroup analyses, we did not find a significant difference between patients with dry AMD and healthy controls (weighted mean difference: 0.34, CI 95% À0.03 to 0.69, p = 0.068), but did find a strong significant difference between patients with neovascular AMD and healthy controls (weighted mean difference: 0.54, CI 95% 0.23 to 0.86, p = 0.00068). Hence, we find that the association between AMD and elevated NLR may have stronger relevance to the neovascular subtype of AMD. However, the clinical value of measuring the NLR remains unclear.

Age‐related macular degeneration (AMD) is the most common cause of visual impairment in the developed world. A number of patients experience complex lifelike visual experiences—Charles Bonnet syndrome (CBS). In this systematic review, our aim was to provide an overview of the CBS literature in relation to AMD, to determine the prevalence of CBS in patients with AMD and to provide an overview of associated demographical and clinical aspects. We searched the literature databases PubMed/MEDLINE, EMBASE, Web of Science, the Cochrane Central, and PsycINFO on 22 March 2019 for studies evaluating the prevalence of CBS in patients with AMD. Two independent authors extracted the data and evaluated risk of bias. Studies were reviewed qualitatively in the text and quantitatively in a meta‐analysis including subgroup analyses for differences between demographic and clinical factors. We identified 18 studies with data on >4303 patients with AMD. We found an overall prevalence of CBS of 15.8% (95% confidence interval: 11.0%–21.2%). When looking at consecutively recruited patients with neovascular AMD from the clinic, prevalence of CBS was 7.2% (95% confidence interval: 4.3%–10.6%). Among visitors to visual rehabilitation centres, prevalence of CBS was 31.6% (95% confidence interval: 21.7%–42.3%). Taken together, we find that CBS is rather common in patients with AMD.