Table 2.

Cox Proportional Hazards Regressions of the Incidence of Dementia (2006–2012) on Social Relationship Measures

	Model 1	Model 2	Model 3	Model 4	Model 5
Sexa	1.22 (0.90 to 1.64)	1.22 (0.91–1.65)	1.20 (0.89–1.61)	1.25 (0.93–1.69)	1.23 (0.92–1.66)
Age: 52–59 years	1 [ref]	1 [ref]	1 [ref]	1 [ref]	1 [ref]
60–69	1.74 (0.91 to 3.34)	1.74 (0.91–3.34)	1.77 (0.92–3.41)	1.72 (0.90–3.30)	1.75 (0.91–3.37)
70–79	6.20 (3.41 to 11.24)*	6.25 (3.44–11.36)*	6.39 (3.52–11.62)*	6.05 (3.33–11.00)*	6.21 (3.41–11.28)*
≥80	18.31 (9.87 to 33.96)*	18.56 (9.96–34.37)*	18.56 (10.06–34.62)*	17.91 (9.66–33.21)*	18.37 (9.89–34.13)*
Education: Lower	1 [ref]	1 [ref]	1 [ref]	1 [ref]	1 [ref]
Intermediate	0.91 (0.67–1.25)	0.92 (0.67–1.26)	0.92 (0.67–1.26)	0.91 (0.67–1.25)	0.93 (0.68–1.27)
Higher	0.90 (0.59–1.37)	0.92 (0.60–1.40)	0.89 (0.58–1.36)	0.91 (0.60–1.39)	0.92 (0.60–1.41)
Wealth (decile)	0.97 (0.92–1.03)	0.97 (0.92–1.03)	0.98 (0.92–1.03)	0.98 (0.93–1.03)	0.98 (0.93–1.04)
Hypertensionb	1.31 (0.99–1.73)	1.30 (0.98–1.71)	1.32 (0.99–1.74)	1.34 (1.02–1.77)*	1.34 (1.01–1.77)*
Diabetesb	1.29 (0.88–1.88)	1.30 (0.89–1.90)	1.34 (0.92–1.97)	1.27 (0.87–1.86)	1.32 (0.90–1.92)
Strokeb	1.29 (0.84–1.97)	1.29 (0.84–1.97)	1.29 (0.84–1.98)	1.29 (0.85–1.98)	1.30 (0.85–1.99)
Coronary heart diseaseb	1.26 (0.90–1.77)	1.25 (0.89–1.77)	1.22 (0.86–1.72)	1.27 (0.90–1.79)	1.24 (0.88–1.75)
Cancerb	1.06 (0.67–1.68)	1.06 (0.67–1.68)	1.08 (0.68–1.70)	1.08 (0.68–1.71)	1.10 (0.69–1.74)
Mobilityc	1.20 (0.86–1.68)	1.20 (0.86–1.69)	1.14 (0.81–1.60)	1.23 (0.88–1.72)	1.17 (0.84–1.65)
Depressiond	1.02 (0.54–1.95)	0.97 (0.50–1.86)	0.79 (0.41–1.55)	1.04 (0.54–1.98)	0.82 (0.41–1.62)
Cognition	0.32 (0.26–0.39)*	0.32 (0.26–0.39)*	0.33 (0.27–0.41)*	0.33 (0.26–0.40)*	0.33 (0.27–0.41)*
Marital statuse	1.77 (1.29–2.44)*	1.77 (1.29–2.44)*	1.96 (1.41–2.71)*	1.98 (1.43–2.73)*	2.11 (1.52–2.92)*
Social isolation: 0		1 [ref]			1 [ref]
1		1.19 (0.89–1.58)			1.11 (0.83–1.48)
2		0.96 (0.52–1.76)			0.88 (0.48–1.62)
3		1.50 (0.54–4.24)			1.22 (0.44–3.40)
Loneliness			1.44 (1.11–1.88)*		1.33 (1.02–1.73)*
Close relationships: 0–1				1 [ref]	1 [ref]
2–3				0.43 (0.26–0.70)*	0.43 (0.26–0.70)*
4–5				0.38 (0.23–0.61)*	0.39 (0.24–0.64)*
6–9				0.34 (0.22–0.53)*	0.36 (0.23–0.57)*
≥10				0.32 (0.20–0.51)*	0.35 (0.22–0.56)*

Notes: Adjusted hazards ratios with 95% confidence intervals. N = 6,677.

^aMale is the reference group.

^bNo illness is the reference group.

^cNo mobility impairment is the reference group.

^dLow depressive symptoms is the reference group.

^eMarried is the reference group.

*p < .05.