Characteristics of participants
Table 1 showed the demographic characteristics of the study objects and a Univariate analysis of life satisfaction with different features. Of the 306 chronic patients, 185 (60.5%) were men and 121 (39.5%) were women. The age range of chronic patients was 45 96 years, with an average age of 64.19 ± 9.83 years. The number of married participants reached 96.1%. At least 51.6% of the respondents live in the city. The majority lived with their spouses (78.8%). The proportion of respondents with medical insurance was 81.7%. Most of the participants stated that they attend social activities occasionally (59.8%). There were differences between life satisfaction in education level, economic situation, and health level. The distribution of diseases among the 306 middle-aged and elderly persons with chronic diseases was shown in Table 2, and the top four diseases were hypertension (45.1%), hepatic diseases (33%), endocrine-metabolic diseases (31%), and heart diseases (29.4%).
Table 1. Univariate analysis of life satisfaction of chronic patients with different characteristics (N=306).
Variables
|
Group
|
N(%)
|
Mean±SD
|
F/t
|
P
|
Gender
|
Male
|
185(60.5)
|
32.54±7.32
|
0.230
|
0.818
|
|
Female
|
121(39.5)
|
32.34±7.61
|
|
|
Age
|
45-64
|
153(50.0)
|
32.36±7.81
|
0.247
|
0.782
|
|
65-74
|
109(35.6)
|
32.81±7.56
|
|
|
|
≥75
|
44(14.4)
|
31.93±5.60
|
|
|
Maritai status
|
Married
|
294(96.1)
|
32.56±7.47
|
0.737
|
0.479
|
|
Single
|
2(0.7)
|
30.50±2.12
|
|
|
|
Divorce
|
10(3.3)
|
29.80±6.56
|
|
|
Education level
|
Primary school and below
|
118(38.6)
|
31.89±6.69
|
2.827
|
0.025
|
|
Junior high school
|
91(29.7)
|
31.11±7.30
|
|
|
|
Senior high school or technical secondary school
|
56(18.3)
|
34.52±6.63
|
|
|
|
Junior college
|
19(6.2)
|
35.26±10.58
|
|
|
|
Bachelor degree or above
|
22(7.2)
|
33.41±9.12
|
|
|
Economic situation
|
In the black
|
130(42.5)
|
34.41±6.73
|
8.374
|
0.001
|
|
Balance of payments
|
136(44.4)
|
31.20±7.47
|
|
|
|
Live beyond one’s income
|
40(13.1)
|
30.40±8.13
|
|
|
Residence
|
Urban
|
158(51.6)
|
33.37±7.48
|
2.509
|
0.083
|
|
Suburb
|
30(9.8)
|
31.20±7.86
|
|
|
|
Rural
|
118(38.6)
|
31.56±7.15
|
|
|
Living condition
|
With spouse
|
241(78.8)
|
32.72±7.67
|
0.749
|
0.523
|
|
With relatives other than spouse
|
45(14.7)
|
31.93±6.43
|
|
|
|
Alone
|
16(5.2)
|
30.88±6.03
|
|
|
|
Other
|
4(1.3)
|
28.75±8.30
|
|
|
Health insurance
|
Free medical care
|
15(4.9)
|
32.87±8.48
|
0.911
|
0.436
|
|
Medical insurance
|
250(81.7)
|
32.72±7.18
|
|
|
|
Other insurance
|
28(9.2)
|
30.57±8.24
|
|
|
|
No
|
13(4.2)
|
30.92±9.16
|
|
|
Social activities
|
Non-participation
|
59(19.3)
|
32.34±7.03
|
2.290
|
0.103
|
|
Occasionally attend
|
183(59.8)
|
31.89±6.86
|
|
|
|
Regularly attend
|
64(20.9)
|
34.19±9.03
|
|
|
Health level
|
Very poor
|
25(8.2)
|
29.64±7.30
|
2.993
|
0.019
|
|
Poor
|
108(35.3)
|
31.19±6.60
|
|
|
|
Average
|
145(47.4)
|
33.63±7.45
|
|
|
|
Good
|
25(8.2)
|
33.49±8.92
|
|
|
|
Very good
|
3(1.0)
|
36.33±13.20
|
|
|
Table 2. Disease status of the patient (N=306).
|
Yes
|
NO
|
Disease distribution
|
N (%)
|
N (%)
|
1 Cardiac
|
90(29.4)
|
216(70.6)
|
|
2 Hypertension
|
138(45.1)
|
168(54.9)
|
|
3 Vascular
|
38(12.4)
|
268(87.6)
|
|
4 Respiratory
|
83(27.1)
|
|
223(72.9)
|
|
5 EENT
|
31(10.1)
|
|
275(89.9)
|
|
6 Upper GI
|
44(14.4)
|
|
262(85.6)
|
|
7 Lower GI
|
55(18.0)
|
|
251(82.0)
|
|
8 Hepatic
|
101(33.0)
|
|
205(67.0)
|
|
9 Renal
|
49(16.0)
|
|
257(84.0)
|
|
10 Other GU
|
49(16.0)
|
|
257(84.0)
|
|
11 Musculo-Skeletal-Integumentary
|
87(28.4)
|
|
219(71.6)
|
|
12 Neurological
|
82(26.8)
|
|
224(73.2)
|
|
13 Endocrine-Metabolic
|
95(31.0)
|
|
211(69.0)
|
|
14 Psychiatric/Behavioral
|
16(5.2)
|
|
290(94.8)
|
|
Bivariate correlation analysis
Table 3 showed the correlational analysis between the study variables. Successful aging was negatively correlated with depression (r = - 0.214, P < 0.01) and positively correlated with life satisfaction (r = 0.337, P < 0.01). Depression was negatively correlated with life satisfaction (r = - 0.278, P < 0.01). The scores for successful aging, depression, and life satisfaction were 51.63 ± 7.22, 7.25 ± 4.36, and 32.46 ± 7.43, respectively.
Table 3. Correlation analysis between successful aging, life satisfaction, and depression among chronic patients (n=306).
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
11
|
1 PHQ9
|
1
|
|
|
|
|
|
|
|
|
|
|
2 Intrinsic dimensions
|
-0.284**
|
1
|
|
|
|
|
|
|
|
|
|
3 Social dimensions
|
-0.239**
|
0.738**
|
1
|
|
|
|
|
|
|
|
|
4 External dimensions
|
-0.237**
|
0.636**
|
0.748**
|
1
|
|
|
|
|
|
|
|
5 Perspective dimensions
|
-0.266**
|
0.791**
|
0.770**
|
0.747**
|
1
|
|
|
|
|
|
|
6 BMLSS
|
-0.278**
|
0.877**
|
0.889**
|
0.871**
|
0.919**
|
1
|
|
|
|
|
|
7 Domain statement
|
-0.152**
|
0.317**
|
0.326**
|
0.281**
|
0.312**
|
0.323**
|
1
|
|
|
|
|
8 Wellness resources
|
-0.156**
|
0.241**
|
0.327**
|
0.213**
|
0.236**
|
0.278**
|
0.599**
|
1
|
|
|
|
9 Positive spirit
|
-0.224**
|
0.259**
|
0.299**
|
0.184**
|
0.262**
|
0.258**
|
0.605**
|
0.656**
|
1
|
|
|
10 Valued relationship
|
-0.187**
|
0.247**
|
0.319**
|
0.234**
|
0.240**
|
0.272**
|
0.487**
|
0.614**
|
0.665**
|
1
|
|
11 SAI
|
-0.214**
|
0.319**
|
0.378**
|
0.273**
|
0.314**
|
0.337**
|
0.813**
|
0.833**
|
0.872**
|
0.831**
|
1
|
**: p < 0.01.
|
|
|
|
|
|
|
|
|
|
|
|
|
Linear regression analysis
We examined the mediating role of depression on the relationship between successful aging and life satisfaction with PROCESS 3.3 macro (model 4) proposed by Hayes after controlling for the demographic variables of education level, economic situation, and health level (Table 4). Model 1 showed that successful aging was positively associated with life satisfaction (β = 0.340, P < 0.001), and successful aging explained the total of 19.50% of the life satisfaction (F = 18.214, P < 0.001, ΔR² = 0.195). Model 2 showed that successful aging was negatively associated with depression (β = -0.140, P < 0.001), and successful aging explained the total of 15.80% of the depression (F = 14.098, P < 0.001, ΔR² =0.158). Model 3 showed that depression was negatively associated with life satisfaction (β = -0.249, P < 0.001), and the explanation of successful aging for life satisfaction decreased from 19.5% to 21.3% (F = 16.227, P < 0.001, ΔR² = 0.213).
Table 4. Linear regression analysis results.
Predictors
|
Model 1 (Life satisfaction)
|
Model 2 (Depression)
|
Model 3 (Life satisfaction)
|
|
β
|
SE
|
t
|
95%CI
|
β
|
SE
|
t
|
95%CI
|
β
|
SE
|
t
|
95%CI
|
Education lever
|
0.324
|
0.333
|
0.974
|
-0.330,0.979
|
0.198
|
0.200
|
0.991
|
-0.195,0.591
|
0.373
|
0.330
|
1.132
|
-0.276,1.023
|
Economic situation
|
-1.824
|
0.588
|
-3.102
|
-2.982,-0.667
|
0.730
|
0.353
|
2.068
|
0.035,1.426
|
-1.643
|
0.587
|
-2.800
|
-2.797,-0.488
|
Health level
|
2.065
|
0.487
|
4.241
|
1.107,3.023
|
-1.779
|
0.292
|
-6.084
|
-2.355,-1.204
|
1.622
|
0.511
|
3.174
|
0.616,2.628
|
Successful aging
|
0.340
|
0.054
|
6.298**
|
0.234,0.446
|
-0.140
|
0.032
|
-4.317**
|
-0.204,-0.076
|
0.305
|
0.055
|
5.539**
|
0.197,0.413
|
Depression
|
|
|
|
|
|
|
|
|
-0.249
|
0.095
|
-2.620**
|
-0.436,-0.062
|
R²
|
|
|
0.195
|
|
|
|
0.158
|
|
|
|
0.213
|
|
F
|
|
|
18.214
|
|
|
|
14.098
|
|
|
|
16.227
|
|
**: p < 0.01
Mediating effect analysis
AMOS 23.0 was used to construct a structural equation model with successful aging as the independent variable, depression as the mediator variable, and life satisfaction as the dependent variable. The structural model was estimated and tested using the great likelihood approach (Fig. 1). The model was corrected once according to the correction index, and the corrected model was shown in Figure 2. Both the pre-correction and post-correction fit indices indicated that the model fits well and was acceptable, and was better after correction, as shown in Table 5. The bias-corrected nonparametric percentile Bootstrap method was used to repeat the sampling 5000 times and set 95% confidence intervals for the mediating effect test, and the results of the mediating effect analysis of the modified model were shown in Table 6. The 95% confidence intervals for the direct and indirect effects of successful aging on life satisfaction did not contain 0. The above indicated that the partial mediation effect model for depression was valid, with a mediation effect of 0.058, which accounted for 13.67% of the total variance.
Table 5. Structural equation model fit index.
Fitness
|
Default Model
|
Modified Model
|
Standard
|
Assessment
|
CMIN/DF
|
2.483
|
1.782
|
1-3
|
Acceptable
|
GFI
|
0.958
|
0.970
|
>0.9
|
Acceptable
|
AGFI
|
0.925
|
0.944
|
>0.9
|
Acceptable
|
NFI
|
0.961
|
0.973
|
>0.9
|
Acceptable
|
CFI
|
0.976
|
0.988
|
>0.9
|
Acceptable
|
IFI
|
0.976
|
0.988
|
>0.9
|
Acceptable
|
TLI
|
0.965
|
0.982
|
>0.9
|
Acceptable
|
PNFI
|
0.667
|
0.648
|
>0.5
|
Acceptable
|
PGFI
|
0.678
|
0.658
|
>0.5
|
Acceptable
|
RMSEA
|
0.070
|
0.051
|
<0.08
|
Adapt
|
Table 6. Analysis of the effects between successful aging and life satisfaction.
Effect
|
Model path
|
Effect value
|
SE
|
LLCI
|
ULCI
|
Proportion of effect
|
Total effect
|
X→Y
|
0.424
|
0.066
|
0.303
|
0.567
|
100%
|
Indirect effect
|
X→Y
|
0.058
|
0.022
|
0.025
|
0.117
|
13.67%
|
Direct effect
|
X→Y
|
0.366
|
0.07
|
0.237
|
0.513
|
86.33%
|