Table 1 Characteristics of all participants with and without depression

Centenarians (%)

837 (54.10%)

247 (78.41%)

590 (47.89%)

Age (year)^a

94.75 ± 9.46

99.18 ± 7.85

93.62 ± 9.51

Women (%)

1115 (72.07%)

270 (85.71%)

845 (68.59%)

Ethnic Han (%)

1388 (89.72%)

278 (88.25%)

1110 (90.09%)

SBP (mmHg)^a

150.91 ± 24.59

152.06 ± 24.94

150.62 ± 24.51

DBP (mmHg)^a

77.97 ± 13.40

77.45 ± 13.68

78.10 ± 13.34

RBC (10¹²/L)^a

4.20 ± 0.66

4.00 ± 0.63

4.25 ± 0.66

Hemoglobin (g/L)^a

119.03 ± 18.28

112.73 ± 18.04

120.65 ± 18.00

MCHC (g/L)^a

313.46 ± 13.13

312.44 ± 13.16

313.72 ± 13.12

WBC (10⁹/L)^a

6.21 ± 1.77

6.14 ± 1.69

6.23 ± 1.79

Neutrophil^a

0.56 ± 0.17

0.57 ± 0.11

0.56 ± 0.18

CRP (mg/L)^a

0.57 ± 2.06

0.71 ± 1.71

0.53 ± 2.14

Immunoglobulin A (g/dL)^a

3.57 ± 1.74

3.79 ± 2.29

3.51 ± 1.57

Immunoglobulin G (g/dL)^a

15.91 ± 3.82

16.11 ± 4.11

15.86 ± 3.75

Immunoglobulin M (g/dL)^a

1.14 ± 0.65

1.13 ± 0.82

1.15 ± 0.60

Immunoglobulin E (g/dL)^a

9.71 ± 30.57

8.91 ± 17.94

9.92 ± 33.03

Complement C3 (mg/dL)^a

105.24 ± 24.13

102.78 ± 21.62

105.87 ± 24.70

Complement C4 (mg/dL)^a

25.91 ± 9.05

25.36 ± 8.47

26.05 ± 9.20