Abstract
Purpose :
This study examines the potential link between leukocyte telomere length (LTL) and glaucoma traits, based on the hypothesis that shortened LTL can induce cellular apoptosis, a process implicated in glaucoma.
Methods :
This cross-sectional analysis involved 164,250 participants with glaucoma traits and standardized LTL measurements in the UK Biobank cohort. Primary analysis examined LTL length as an independent risk factor for glaucoma prevalence. Secondary analyses examined associations with intraocular pressure (IOP), macular retinal nerve fiber layer (mRNFL), and ganglion cell inner plexiform layer (mGCIPL) thicknesses after controlling for age, sex, ethnicity, deprivation, diabetes, body mass index, systolic blood pressure, physical activity, alcohol, smoking, obesity, and IOP polygenic risk score. Mediation analysis further investigated the relationship between age, LTL, and primary and secondary endpoints.
Results :
Participants were age-stratified (<50 years, 50-60 years, 60-70 years) due to the strong correlation between age and LTL. After adjusting for multiple covariates, there was no significant association between LTL and glaucoma (<50 years: P=0.52; 50-60 years: P=0.81; 60-70 years: P=0.29). Similarly, there was no significant association between LTL and IOP (<50 years: P=0.05; 50-60 years: P=0.07; 60-70 years: P=0.82); mRNFL thickness (<50 years: P= 0.32; 50-60 years: P=0.49; 60-70 years: P=0.23); nor mGCIPL thickness (<50 years: P= 0.64; 50-60 years: P=0.60; 60-70 years: P=0.56).
The mediation analysis indicated that LTL did not mediate the relationship between older age and increasing risk of glaucoma (P=0.47), or the relationship between age and mGCIPL thickness (P=0.40). Interestingly, longer LTL showed a minor suppression effect on the relationship between age and IOP (-1.3% suppression; P=0.01). Furthermore, LTL modestly mediates the relationship between increasing age and thinner mRNFL thickness (2.4% mediation; P=0.005).
Conclusions :
LTL was not associated with prevalent glaucoma or glaucoma-related measures independently of age and other covariates. LTL may partly mediate the relationship between age and mRNFL thickness. This warrants future investigation into how glaucoma-related variables might be modified by known lifestyle factors influencing LTL.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.