Do all systems age together?
Aihie Sayer A., Osmond C., Briggs R., Cooper C.
BACKGROUND: Aging changes in different body system are well described, but few studies have considered the relationship between them. OBJECTIVE: The purpose of this study was, therefore, to investigate the interrelationships between markers of aging in different parts of the body. METHODS: A cross-sectional study design was used. Structural and functional markers of aging were measured in a number of different body systems. RESULTS: Conditional independence analysis demonstrated that the aging markers selected clustered into two groups, either related to chronological age or adult height. Visual acuity, lens opacity, hearing threshold, cognitive decline, and the number of teeth were associated with age, while systolic blood pressure and skin thickness were related to height. Grip strength was associated with both. CONCLUSIONS: The differential associations of the aging markers with chronological age and adult height suggest that different systems do not age together. This may have relevance for understanding what underlies aging, and these preliminary findings now require replication in other aging cohorts.