Table 2 Association between baseline characteristics and the trajectories of frailty, cognitive impairment, and depressive symptoms in older adults in China (2011–2018)

Age (every 5-year increase; continuous)

1.93*

(1.77–2.13)

1.16*

(1.07–1.26)

1.68*

(1.55–1.83)

Female (ref: Male)

2.66*

(2.11–3.36)

1.67*

(1.41–1.98)

2.31*

(1.93–2.77)

Human capital

Education (ref: Elementary school or higher)

No formal education

12.99*

(9.84–17.15)

1.37

(1.06–1.76)

23.14*

(18.43–29.07)

Less than elementary school

2.43*

(1.83–3.24)

1.39*

(1.14–1.69)

4.31*

(3.48–5.35)

Work status (ref: Currently working)

Retired

2.66*

(2.08–3.40)

1.49*

(1.23–1.80)

1.12

(0.92–1.37)

Not employed/Never worked

3.05*

(1.57–5.92)

2.19*

(1.31–3.66)

1.17

(0.63–2.17)

Social capital

Not married^a (ref: Married)

1.39

(1.07–1.80)

1.22

(0.98–1.51)

1.33

(1.06–1.66)

Empty nester (ref: Living with children)

0.88

(0.71–1.08)

0.99

(0.84–1.16)

0.89

(0.75–1.06)

No participation in any social activities (ref: Any social activity participation)

1.98*

(1.61–2.45)

1.26

(1.07–1.47)

1.69*

(1.43–2.01)

Financial capital

Childhood family financial situation^b (ref: Same)

A lot better off/somewhat better off

1.28

(0.85–1.93)

1.23

(0.93–1.64)

1.22

(0.90–1.67)

Somewhat worse off/A lot worse off

1.66*

(1.33–2.07)

1.28

(1.08–1.52)

1.15

(0.96–1.38)

Per capita household consumption (ref: Quartile 4)

Quartile 1

1.18

(0.83–1.66)

0.97

(0.74–1.27)

1.58*

(1.19–2.10)

Quartile 2

1.28

(0.91–1.78)

1.06

(0.83–1.37)

1.65*

(1.26–2.18)

Quartile 3

1.08

(0.78–1.50)

1.17

(0.93–1.47)

1.27

(0.97–1.68)

Health capital

Childhood health^c (ref: About average)

Much healthier/somewhat healthier

0.75

(0.59–0.95)

0.85

(0.72–1.02)

0.75*

(0.62–0.90)

Somewhat less healthy/Much less healthy

1.34

(0.97–1.84)

1.47

(1.13–1.91)

1.12

(0.84–1.48)

Self-rated health (ref: Fair)

Very good/good

0.32*

(0.23–0.46)

0.31*

(0.24–0.40)

0.60*

(0.48–0.74)

Poor/very poor

9.76*

(7.69–12.39)

4.59*

(3.83–5.51)

2.23*

(1.81–2.75)

Structural factor

Hukouand residence (ref: Urban hukou, urban residence)

Rural hukou, rural residence

3.98*

(2.83–5.61)

1.40

(1.11–1.75)

4.21*

(3.17–5.60)

Rural hukou, urban residence

2.02*

(1.38–2.95)

0.92

(0.71–1.19)

2.65*

(1.94–3.63)

Urban hukou, rural residence

1.58

(0.75–3.35)

1.13

(0.73–1.74)

1.71

(0.97–3.01)