Table 1.

Studies reporting plasma/serum levels of pro-inflammatory markers with aging.

Marker	Study	Main finding
TNFα	Bruunsgaard et al., 2000	↑ plasma [TNFα] in elderly (81 years) vs. young adults (19–31 years)
	Bruunsgaard et al., 1999	↑ plasma [TNFα] in elderly (>80 years) (2.5 pg/ml) vs. young adults (18–30 years) (1.4 pg/ml)
	Paolisso et al., 1998	Significant correlation between age and TNFα (r = 0.64)
	Paik et al., 2013	↑ serum [TNFα] in elderly ♀ (60–79 years) (>9 pg/ml) vs. younger ♀ (30–59 years) (±7 pg/ml)
IL-6	Wei et al., 1992	↑ plasma [IL-6] in elderly (55–75 years) ♂ vs. younger (26–54 years) ♂ and significant correlation between age and IL-6 (r = 0.28)
	Hager et al., 1994	Significant correlation between age and IL-6 (r = 0.47)
	McKane et al., 1994	Significant correlation between age and IL-6 in ♀ (r = 0.48)
	Checouich et al., 1995	Significant correlation between age and IL-6 in ♀ (r = 0.75)
	Cohen et al., 1997	↑ mean log(IL-6) and median IL-6 levels in elderly >90 years vs. elderly 80–89 years vs. elderly 70–79 years
	Harris et al., 1999	↑ log(IL6) values in elderly >80 years (0.96 ± 0.65 pg/ml) vs. 71–72 years (0.73 ± 0.66 pg/ml)
	Ferrucci et al., 2005	↑ plasma [IL-6] in elderly >75 years (>1.4 pg/ml) vs. young adults (20–39 years) (0.6 pg/ml)
hs-CRP	Ferrucci et al., 2005	↑ plasma [CRP] in elderly >75 years (>2.6 mg/l) vs. young adults (20–39 years) (1.0 mg/l)
	Puzianowska-Kuznicka et al., 2016	↑ plasma [CRP] in elderly >80 years (>2.4 mg/l) vs. elderly 65–69 years (2.2 mg/l)
	Paik et al., 2013	↑ serum [CRP] in elderly ♀ (>50 years) (>1.1 mg/l) vs. younger ♀ (30–59 years) (±0.95 g/l)

TNFα, tumor necrosis factor α; IL-6, interleukin 6; hs-CRP, high-sensitive C-reactive protein.