Abstract
Purpose: :
Nuclear cataract is an independent predictor of mortality, and has been suggested as a biological marker of aging. Peripheral blood white cell telomere length may also be a biomarker of aging, with shortened telomere length associated with senescence, smoking and obesity as well as several age–related diseases. This study examined the relationship between nuclear cataract, telomere length and age in an unselected cohort of female subjects over the age of 50 years.
Methods: :
Nuclear cataract was measured using lens Scheimpflug photography in 528 female subjects aged 50 to 75 years of age, who were part of a twin study. Nuclear cataract was measured from the central nuclear dip (NUCDIP) of the lens. Telomere length in the form of the mean of the terminal telomere restriction fragments (TRF) from peripheral leucocytes was measured in duplicate using Southern blot. Smoking status was assessed and BMI measured.
Results: :
Both NUCDIP and TRF length were significantly correlated with age (r=0.58 and –0.18, p<0.0001), and with each other (r=0.17, p=0.0001). Multiple regression showed NUCDIP to be significantly associated with age (p<0.001) but association with TRF was only marginal when adjusted for age (p=0.06). Addition of smoking status (p=0.007) and BMI (p=0.69) did not substantially alter the marginal association observed between NUCDIP and TRF adjusted for age.
Conclusions: :
Nuclear cataract is strongly related to age, telomere length and smoking status. While both nuclear cataract and telomere length may be biomarkers of aging, the association between telomere length and nuclear cataract reduced in this population–based sample when effects of age and smoking were taken into account.
Keywords: cataract • clinical (human) or epidemiologic studies: risk factor assessment • aging