1 research outputs found
Detection of a novel, integrative aging process suggests complex physiological integration
Abstract: Many studies of aging examine biomarkers one at a time, but complex systems theory and
network theory suggest that interpretations of individual markers may be context-dependent.
Here, we attempted to detect underlying processes governing the levels ofmany biomarkers
simultaneously by applying principal components analysis to 43 common clinical biomarkers
measured longitudinally in 3694 humans from three longitudinal cohort studies on two continents
(Women’s Health and Aging I & II, InCHIANTI, and the Baltimore Longitudinal Study on
Aging). The first axis was associated with anemia, inflammation, and low levels of calcium
and albumin. The axis structure was precisely reproduced in all three populations and in all
demographic sub-populations (by sex, race, etc.); we call the process represented by the
axis “integrated albunemia.” Integrated albunemia increases and accelerates with age in all
populations, and predicts mortality and frailty – but not chronic disease – even after controlling
for age. This suggests a role in the aging process, though causality is not yet clear.
Integrated albunemia behaves more stably across populations than its component biomarkers,
and thus appears to represent a higher-order physiological process emerging from the
structure of underlying regulatory networks. If this is correct, detection of this process has
substantial implications for physiological organizationmore generally