Age-related macular degeneration (AMD) was found to be associated with relative telomere length in women specifically when investigating older patients.
The study used the Altersbezogene Untersuchungen zur Gesundheit der University of Regensburg study as a participant base. Individuals who lived near Regensburg, were aged at least 70 years, and willing to participate were included in the study. Information on sociodemographic data, lifestyle factors, metabolic parameters, medication use, and general and ocular morbidities were obtained from interview-based questionnaires and medical examinations.
At least 2 images of each eye were taken for each participant; the study also included color fundus photography of the central retina. The images of the eyes were the basis of the 3 groups that participants were split into: no AMD, mild/moderate/severe early AMD, late AMD.
There were 172 participants with late AMD (98 with neovascular AMD, 37 with geographic atrophy, and 37 with a combined subtype) and 455 participants with early AMD. There were 1635 participants without AMD who were also included in the analysis.
Participants without AMD had the longest mean (SD) RTL (0.91 [0.18]) and participants with late AMD had the shortest RTL (0.86 [0.17]).
A regression analysis demonstrated that there was an odds ratio (OR) of 1.08 (95% CI, 1.01-1.15) and 1.09 (95% CI, 0.99-1.20) for the risk of early and late AMD per an RTL decline of 0.1 unit. Increasing RTL increased the probability of being free of AMD and increased RTL also decreased the probability of early and late AMD. The probability of AMD increases as RTL decreases.
Logistic regression models that looked for any AMD as an outcome demonstrated that a deline of 0.1 RTL unit increased the probability for AMD by 8% in an age- and sex-adjusted model (OR, 1.08; 95% CI, 1.02-1.14). The risk estimate per 0.1 RTL unit decrease is comparable to the estimate of a 1-year increase in age (OR, 1.09; 95% CI, 1.07-1.11)
The effect of RTL on AMD was only present in women (OR, 1.14; 95% CI, 0.93-1.10) and not men in the age-adjusted regression model. Distribution of AMD status was similar in both sexes. RTL declined with increasing age whereas AMD risk increased with increasing age.
There were some limitations to this study. There are limitations to color fundus photography, such as false-negative results. More than 96% of participants reported medication use and had comorbidities due to their age, which makes comparison and identification of predictors more difficult. The researchers could not disentangle whether shorter telomeres increased the risk of developing AMD or if they were a marker of aging beyond chronological age. There is a possibility that shorter telomeres were a consequence of AMD or related processes.
The researchers concluded that their research demonstrated an association between short RTL and AMD in the older population that was independent from other risk factors. The association was present in women and was driven by biological age that was, to some extent, independent from chronological age.
The authors said that further studies were needed on the progression of the disease, including follow-up data, to get a better understanding of the pathomechanisms of AMD.
Koller A, Brandl C, Lamina C, et al. Relative telomere length is associated with age-related macular degeneration in women. Invest Ophthalmol Vis Sci. 2022;63(5):30. doi:10.1167/iovs.63.5.30