Longitudinal telomere length shortening and cognitive and physical decline in later life: the Lothian Birth Cohorts 1936 and 1921

Telomere length is hypothesised to be a biological marker of both cognitive and physical ageing. Here we measure telomere length, and cognitive and physical abilities at mean ages 70, 73 and 76 years in the Lothian Birth Cohort 1936 (LBC1936), and at mean ages 79, 87, 90 and 92 years in the Lothian Birth Cohort 1921 (LBC1921). We investigate whether telomere length change predicts change in cognitive and physical abilities. In LBC1936 telomere length decreased by an average of 65 base pairs per year and in LBC1921 by 69 base pairs per year. However, change in telomere length did not predict change in cognitive or physical abilities. This study shows that, although cognitive ability, walking speed, lung function and grip strength all decline with age, they do so independently of telomere length shortening.