Thiazolidinedione Use and Retinal Fluid in the Comparison of Age-Related Macular Degeneration Treatments Trials

BACKGROUND: Thiazolidinediones, commonly used antidiabetic medications, have been associated with an increased risk of development of diabetic macular oedema and increased vascular endothelial cell permeability. Macular neovascularisation in age-related macular degeneration (AMD) and associated fluid leakage may be influenced by thiazolidinediones. This study aims to determine the association between thiazolidinedione usage and retinal morphological outcomes or visual acuity (VA) in patients treated with bevacizumab or ranibizumab for neovascular AMD (nAMD). METHODS: Secondary analysis of data from the Comparison of Age-related Macular Degeneration Treatments Trials. Participant self-reported diabetes status and thiazolidinedione usage at baseline. VA, intraretinal, subretinal and subretinal pigment epithelium fluid, and foveal thickness of retinal layers were evaluated at baseline and during 2-year follow-up. Comparisons of outcomes between thiazolidinedione usage groups were adjusted by macular neovascularisation lesion type in multivariable regression models. RESULTS: Patients taking thiazolidinedione (n=30) had lower adjusted mean VA score at baseline (difference -6.2 letters; p=0.02), greater proportion with intraretinal fluid (IRF) at year 2 (75% vs 50%, adjusted OR 2.8; p=0.04), greater mean decrease in subretinal tissue complex thickness from baseline at year 1 (difference -75.1 um; p=0.02) and greater mean decrease in subretinal thickness at year 1 (difference -41.9 um; p=0.001) and year 2 (difference -43.3 um; p=0.001). CONCLUSIONS: In this exploratory analysis, patients with diabetes taking thiazolidinediones and treated with bevacizumab or ranibizumab for nAMD had worse baseline mean VA, greater reductions in subretinal and subretinal tissue complex thickness from baseline, and greater proportions with IRF comparing to patients not taking thiazolidinediones. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov NCT00593450

Predominantly Persistent Intraretinal Fluid in the Comparison of Age-related Macular Degeneration Treatments Trials

PURPOSE: To describe predominantly persistent intraretinal fluid (PP-IRF) and its association with visual acuity (VA) and retinal anatomic findings at long-term follow-up in eyes treated with pro re nata (PRN) ranibizumab or bevacizumab for neovascular age-related macular degeneration. DESIGN: Cohort within a randomized clinical trial. PARTICIPANTS: Participants in the Comparison of Age-related Macular Degeneration Treatments Trials (CATT) assigned to PRN treatment. METHODS: The presence of intraretinal fluid (IRF) on OCT scans was assessed at baseline and monthly follow-up visits by Duke OCT Reading Center. Predominantly persistent intraretinal fluid through week 12, year 1, and year 2 was defined as the presence of IRF at the baseline and in ≥ 80% of follow-up visits. Among eyes with baseline IRF, the mean VA scores (letters) and changes from the baseline were compared between eyes with and those without PP-IRF. Adjusted mean VA scores and changes from the baseline were also calculated using the linear regression analysis to account for baseline patient features identified as predictors of VA in previous CATT studies. Furthermore, outcomes were adjusted for concomitant predominantly persistent subretinal fluid. MAIN OUTCOME MEASURES: Predominantly persistent intraretinal fluid through week 12, year 1, and year 2; VA score and VA change; and scar development at year 2. RESULTS: Among 363 eyes with baseline IRF, 108 (29.8%) had PP-IRF through year 1 and 95 (26.1%) had PP-IRF through year 2. When eyes with PP-IRF through year 1 were compared with those without PP-IRF, the mean 1-year VA score was 62.4 and 68.5, respectively (P = 0.002), and was 65.0 and 67.4, respectively (P = 0.13), after adjustment. Predominantly persistent intraretinal fluid through year 2 was associated with worse adjusted 1-year mean VA scores (64.8 vs. 69.2; P = 0.006) and change (4.3 vs. 8.1; P = 0.01) as well as worse adjusted 2-year mean VA scores (63.0 vs. 68.3; P = 0.004) and changes (2.4 vs. 7.1; P = 0.009). Predominantly persistent intraretinal fluid through year 2 was associated with a higher 2-year risk of scar development (adjusted hazard ratio = 1.49; P = 0.03). CONCLUSIONS: Approximately one quarter of eyes had PP-IRF through year 2. Predominantly persistent intraretinal fluid through year 1 was associated with worse long-term VA, but the relationship disappeared after adjustment for baseline predictors of VA. Predominantly persistent intraretinal fluid through year 2 was independently associated with worse long-term VA and scar development

Impacts of birds of prey on gamebirds in the UK: a review

The influence of predators on the distribution, density and dynamics of their prey species has long been of interest to ecologists and wildlife managers. Where the prey population is also utilised by humans, conflicts may arise through competition for a limited resource. Because gamebird shooting in the UK provides employment, recreation and income, the impact of birds of prey on gamebird populations has been the subject of intense debate for many years. A variety of approaches has been used to assess the impacts that raptors have on gamebird populations. Here we review the applicability and limitations of the methods used and assess the scientific evidence for population-level and economic impacts of raptors on gamebird populations in the UK. Raptors may, in some situations, take large numbers of gamebirds and may be an important proximate cause of mortality, although few studies have assressed the impacts of raptors on either breeding or pre-shooting densities. Two exceptions are studies of Hen Harrier and Peregrine predation on Red Grouse on moorland in Scotland and Sparrowhawk predation on Grey Partridge on farmland in England. Both these studies suggested that raptors could have population-level impacts when their gamebird prey was already at low density. Studies on predation of captively bred gamebirds suggest that numbers taken by raptors at release pens vary considerably and in a few cases raptors have been documented killing relatively large numbers. On the whole, however, it appears that raptors account for a relatively small proportion of mortality among released birds and the impact on subsequent shooting bags is unknown. We summarise important gaps in current knowledge and recommend specific areas for future research