Table 2.

Associations of perceived stress score (per 1-point increment) with loneliness and depressive symptoms and the mediation proportion of perceived stress in loneliness and depressive symptoms attributed to sleep quality (N = 734)

Outcomes	β/OR (95% CI)			Mediation proportion, % (95% CI) d	P value
	Model 1 a	Model 2 b	Model 3 c
Loneliness score	0.07 (0.06, 0.08)	0.07 (0.05, 0.08)	0.06 (0.05, 0.08)	5.3 (1.3, 10.0)	0.014
Depression score	0.45 (0.40, 0.49)	0.42 (0.38, 0.46)	0.38 (0.34, 0.42)	9.7 (6.2, 14.0)	< 0.001
Loneliness e	1.17 (1.11, 1.22)	1.17 (1.11, 1.23)	1.16 (1.10, 1.22)	4.3 (-1.9, 13.0)	0.170
Depressive symptoms f	1.34 (1.26, 1.42)	1.36 (1.27, 1.45)	1.35 (1.26, 1.44)	5.8 (2.2, 11.0)	< 0.001

OR, odds ratio; CI, confidence interval

^a Model 1 was adjusted for age, and sex

^b Model 2 was further adjusted for marital status, educational level, occupational status, family income per month, body mass index, physical activity, drinking status, smoking status, psychological disease history, and self-rated health status based on model 1

^c Model 3 was further adjusted for the Pittsburgh Sleep Quality Index score based on model 2

^d The model was adjusted for age, sex, marital status, educational level, occupational status, family income per month, body mass index, physical activity, drinking status, smoking status, psychological disease history, and self-rated health status

^e Participants were considered as experiencing loneliness if they had a loneliness score ≥ 6

^f Participants were considered as having depressive symptoms if they had a depression score ≥ 10