Circulating cell-free DNA is associated with mortality and inflammatory markers in nonagenarians: The Vitality 90+ Study

Aging is characteristically accompanied by a low-grade inflammatory state and increased cellular death. In this study, we analyzed the associations between the plasma cell-free DNA (cf-DNA) level and immunoinflammatory factors and 4-year mortality. The distribution of qualitative cf-DNA patterns in relation to the total cf-DNA concentration and the antinuclear antibody (ANA) serostatus was also evaluated. The study population consisted of n = 258 nonagenarians who were participants in the Vitality 90 + Study. Cf-DNA levels were positively correlated with the C-reactive protein (CRP) level, the interleukin-1 receptor antagonist (IL-1ra) level, the serum amyloid A (SAA) level and the indoleamine 2,3-dioxygenase enzyme activity (IDO), weight and chair-stand test time and inversely correlated with the HDL cholesterol level. The total cf-DNA concentration also remained as an independent predictor of 4-year all-cause mortality. A predominance of low-molecular-weight cf-DNA was observed in ANA-seropositive subjects but this cf-DNA pattern was not associated with mortality. The cf-DNA concentration could thus represent a novel biomarker for systemic inflammation and mortality in the elderly.