Mediating Role of Depression Between Diabetes Management Self-Efficacy and Diabetes Self-Care Behavior Among Elderly Type 2 Diabetes Mellitus Patients in China

Figures & data

Table 1 Participants’ Demographic Characteristics, Diabetes-Related Characteristics, Self-Care Behavior, Self-Efficacy, and Depression (n = 240)

Variable	Mean (SD)	N(%)
Age (years)	73.76 (7.01)
60–74		128 (53.3)
75–89		112 (46.7)
Gender
Male		108 (45.0)
Female		132 (55.0)
Marriage
Married		184 (76.7)
No married		56 (23.3)
Education
Primary school or below		83 (34.6)
Junior high school		85 (35.4)
Senior high school		41 (17.1)
College or above		31 (12.9)
Household monthly income (CNY)
<2000		36 (15.0)
2000–4000		91 (37.9)
>4000		113 (47.1)
Diabetes duration (years)	12.47 (8.08)
1–10		129 (53.8)
>10		111 (46.2)
Personal monthly expenditure on diabetes (CNY)
<200		87 (36.3)
200–400		105 (43.7)
>400		48 (20.0)
BMI	23.73 (2.93)
≥24		104 (35.8)
Self-care behavior (SDSCA total)	37.84 (12.27)
Better self-care behavior		54 (22.5)
General diet	9.76 (4.28)
Specific diet	7.32 (2.63)
Exercise	5.83 (4.09)
Blood sugar testing	4.74 (4.59)
Foot care	4.17 (5.08)
Medication taking	6.02 (2.12)
Self-efficacy	139.12 (40.18)
High level		89 (37.1)
Depression	5.03 (4.30)
Depressed		112 (46.7)
No depressed		128 (53.3)

Note: SDSCA was used to evaluate the level of self-care behavior.

Abbreviation: SDSCA, the Summary of Diabetes Self-Care Activities.

Table 2 Comparison of Participants’ Demographic and Diabetes-Related Characteristics with Self-Care Behavior

Self-Care Behavior	Group	Mean (SD)	t	p value
SDSCA total	Marriage		1.979	0.049*
	Married	38.70 (12.49)
	Unmarried	35.01 (11.14)
	Education		−3.048	0.003**
	Primary school or below	34.58 (10.19)
	Junior high school or above	39.57 (12.93)
	Personal monthly expenditure on diabetes (CNY)		−2.288	0.023*
	≤200	35.46 (12.09)
	>200	39.20 (12.20)
	BMI		2.265	0.024*
	<24	39.40 (12.24)
	≥24	35.81 (12.07)
	Self-efficacy		−6.116	0.000***
	Medium and below level	34.38 (11.57)
	High level	43.71 (11.19)
	Depression		4.050	0.000***
	Depressed	40.75 (13.38)
	Non-depressed	34.52 (9.92)
General diet	Age (years)		−3.528	0.001**
	60–74	8.87 (4.54)
	75–89	10.78 (3.73)
	Diabetes duration (years)		−2.752	0.006**
	1–10	9.06 (4.53)
	>10	10.57 (3.84)
	BMI
	<24	10.63 (4.03)	3.711	0.000***
	≥24	8.62 (4.36)
	Self-efficacy		−6.151	0.000***
	Medium and below level	8.54 (4.36)
	High level	11.82 (3.26)
	Depression		3.144	0.002**
	Depressed	8.85 (4.12)
	Non-depressed	10.55 (4.28)
Specific diet	Household monthly income (CNY)		−2.247	0.026*
	≤4000	6.97 (2.65)
	>4000	7.73 (2.56)
Exercise	Gender		2.011	0.045*
	Male	6.42 (4.07)
	Female	5.36 (4.06)
	Marriage		3.340	0.001**
	Married	6.31 (3.94)
	Unmarried	4.27 (4.21)
	Education		−3.827	0.000***
	Primary school or below	4.48 (3.93)
	Junior high school or above	6.54 (4.00)
	Self-efficacy		−5.381	0.000***
	Medium and below level	4.80 (4.04)
	High level	7.58 (3.57)
	Depression		6.324	0.000***
	Depressed	4.18 (3.96)
	Non-depressed	7.28 (3.64)
Blood sugar testing	Personal monthly expenditure on diabetes (CNY)		−2.155	0.032*
	≤200	3.90 (4.12)
	>200	5.22 (4.79)
Foot care	Marriage		2.443	0.015*
	Married	4.61 (5.30)
	Unmarried	2.73 (4.00)
	Education		−3.501	0.001**
	Primary school or below	2.63 (3.87)
	Junior high school or above	4.99 (5.46)
	Household monthly income (CNY)		−2.249	0.025*
	≤4000	3.48 (4.77)
	>4000	4.95 (5.33)
	Personal monthly expenditure on diabetes (CNY)		−2.533	0.012*
	≤200	3.08 (4.63)
	>200	4.79 (5.24)
	Self-efficacy		−5.478	0.000***
	Medium and below level	2.87 (4.18)
	High level	6.38 (5.71)
	Depression		3.247	0.001**
	Depressed	5.15 (5.80)
	Non-depressed	3.05 (3.85)
Medication taking	Diabetes duration (years)		−2.069	0.040*
	1–10	5.75 (2.37)
	>10	6.32 (1.75)
	Self-efficacy		2.342	0.020*
	Medium and below level	6.26 (1.76)
	High level	5.60 (2.59)

Notes: SDSCA was used to evaluate the level of self-care behavior. *p < 0.05; **p < 0.01; ***p < 0.001.

Abbreviation: SDSCA, the Summary of Diabetes Self-Care Activities.

Table 3 Correlation Between Self-Efficacy, Depression and Self-Care Behavior

Outcome Variables	1	2	3
1. Self-care behavior	1.00	–	–
2. Self-efficacy	0.311**	1.00	–
3. Depression	−0.264**	−0.486**	1.00

Note: **p < 0.01.

Table 4 The Mediation Effect of Depression Between Self-Efficacy and Self-Care Behaviors

Participants	Variable	Path c		Path c’ and b		Path a		Path a×b
		B	SE	B	SE	B	SE	B	SE	LLCI	ULCI
Total	Self-efficacy	0.095***	0.019	0.073***	0.021	−0.052***	0.006
	Depression	–	–	−0.423*	0.120	–	–	0.022*	0.011	0.004	0.046
	R^2adj	0.097		0.113		0.237
	F	25.420		15.137		73.738
Age:60–74	Self-efficacy	0.094***	0.025	0.104***	0.029	−0.049***	0.009
	Depression	–	–	0.203	0.266			−0.010	0.013	−0.036	0.015
	R^2adj	0.098		0.103		0.212
	F	13.751		7.144		33.795
Age:75–89	Self-efficacy	0.091**	0.028	0.034	0.031	−0.054***	0.009
	Depression	–	–	−1.061***	0.288	–	–	0.058**	0.020	0.027	0.104
	R^2adj	0.088		0.188		0.258
	F	10.558		12.655		38.174

Notes: ***p < 0.001; **p < 0.01; *p < 0.05.

Figure 1 Schematic model of depression as the mediator between self-efficacy and self-care behaviors.