Table 1 Characteristics of the study participants according to physical frailty status
Characteristics | Total | Not frail (n = 365) | Pre-frail (n = 364) | Frail (n = 62) | p value for difference between not frail and frail |
|---|---|---|---|---|---|
Age (years), mean (SD) | 69.5 (0.84) | 69.4 (0.88) | 69.6 (0.81) | 69.5 (0.70) | 0.61 |
Female, number (%) | 398 (50.3) | 184 (50.4) | 181 (49.7) | 33 (53.2) | 0.17 |
Epigenetic clock measures (years), mean (SD) | |||||
 Extrinsic epigenetic age acceleration | − 0.39 (7.11) | − 1.03 (7.55) | − 0.08 (6.73) | 1.50 (6.12) | 0.013 |
 Intrinsic epigenetic age acceleration | − 0.45 (5.99) | − 0.78 (6.34) | − 0.23 (5.68) | 0.20 (5.65) | 0.254 |
Number of chronic physical illnesses, median (IQR) | 1 (0–2) | 1 (0–1) | 1 (0–2) | 2 (1–2) | 0.0001 |
Smoking status, number (%) | |||||
 Never | 374 (47.3) | 182 (49.9) | 168 (46.2) | 24 (38.7) | 0.005 |
 Ex-smoker | 334 (42.2) | 154 (42.2) | 155 (42.6) | 25 (40.3) |  |
 Current smoker | 83 (10.5) | 29 (7.95) | 41 (11.3) | 13 (21.0) |  |
Units of alcohol per week, median (IQR) | 6 (0.5–14) | 1 (0–7) | 4.25 (0.5–14) | 0 (0.25–10) | 0.009 |
White blood cell counts (109/L), median (IQR) | |||||
 Basophils | 0.04 (0.03–0.05) | 0.04 (0.03–0.05) | 0.04 (0.03–0.05) | 0.04 (0.03–0.06) | 0.096 |
 Eosinophils | 0.13 (0.08–0.21) | 0.12 (0.07–0.20 | 0.12 (0.08–0.22) | 0.14 (0.08–0.24) | 0.204 |
 Monocytes | 0.49 (0.40–0.61) | 0.48 (0.38–0.58) | 0.52 (0.42–0.63) | 0.51 (0.45–0.61) | 0.034 |
 Lymphocytes | 1.73 (1.40–2.15) | 1.68 (1.37–2.05) | 1.77 (1.41–2.27) | 1.75 (1.48–2.23) | 0.105 |
 Neutrophils | 4.42 (3.29–5.27) | 4.09 (3.23–5.03) | 4.29 (3.31–5.36) | 4.60 (3.63–5.89) | 0.007 |