Description of the participants
A total of 350 participants with a mean age of 71.05 years (SD = 6.22) completed the survey. The percentage of participants with an education level from primary school to university was 51.1%-8%. Of all the participants, 72.9% reported to be married. 154 (44%) were male, and 196(56%) were female as shown in Table 1.
Table 1 Demographic characteristics.
Demographics
|
Classification
|
Frequency
|
Percent
|
Cumulative percent
|
Gender
|
Female
|
196
|
56
|
56
|
|
Male
|
154
|
44
|
100
|
Age
|
60-70
|
155
|
44.3
|
44.3
|
|
70-80
|
143
|
40.9
|
85.1
|
|
>80
|
52
|
14.9
|
100
|
Education level
|
Primary school and below
|
179
|
51.1
|
51.1
|
|
Secondary school
|
93
|
26.6
|
77.7
|
|
High school
|
50
|
14.3
|
92.0
|
|
College graduate or above
|
28
|
8.0
|
100
|
Marital status
|
Married
|
255
|
72.9
|
72.9
|
|
Single (never married, divorced, separated and widowed)
|
95
|
17.1
|
100
|
Household monthly income
|
Low (≤1000 rmb)
|
176
|
50.3
|
50.3
|
|
Middle (1001–2000 rmb)
|
127
|
36.3
|
86.6
|
|
High (>2000 rmb)
|
47
|
13.4
|
100
|
Correlation analyses between the variables
As presented in Table 2, total score of mental health of the elderly was positively related with education level, household monthly income, role-physical, pysical functioning, general health, vitality, social functioning, role-emotional, mental health, total score of quality of life (r=0.618**,0.407**,0.711**, 0.869**, 0.681**, 0.554**, 0.470**,.649**,0.677** and 0.701**, respectively). The total score of mental health of the elderly was negatively correlated with gender, age, marital status, bodily pain(r=-0.108*, -0.395**,-0.131* and -0.303** , respectively).
Table 2 Correlation analysis among variables
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
11
|
12
|
13
|
14
|
15
|
1.gender
|
|
1.000
|
.002
|
-.169**
|
-.013
|
-.062
|
-.108*
|
.051
|
-.056
|
.043
|
-.029
|
.199*
|
.206**
|
-.013
|
.129*
|
.143**
|
|
2.age
|
|
.002
|
1.000
|
-.431**
|
-.288**
|
.019
|
-.395**
|
-.372**
|
-.298**
|
.144**
|
-.332**
|
-.276**
|
-.261**
|
-.319**
|
-.336**
|
-.354**
|
|
3.Eu
|
|
-.169**
|
-.431**
|
1.000
|
.576**
|
-.033
|
.618**
|
.575**
|
.551**
|
-.314**
|
.562**
|
.408**
|
.355**
|
.523**
|
.509**
|
.499**
|
|
4.Hmi
|
|
-.013
|
-.288**
|
.576**
|
1.000
|
.062
|
.407**
|
.400**
|
.409**
|
-.196**
|
.373**
|
.311**
|
.264**
|
.343**
|
.368**
|
.355**
|
|
5.Mar
|
|
-.062
|
.019
|
-.033
|
.062
|
1.000
|
-.131*
|
-.110*
|
-.130*
|
.016
|
-.071
|
-.126*
|
-.097
|
-.076
|
-.124*
|
-.135*
|
|
6.EMH
|
|
-.108*
|
-.395**
|
.618**
|
.407**
|
-.131*
|
1.000
|
.711**
|
.869**
|
-.303**
|
.681**
|
.554**
|
.470**
|
.649**
|
.677**
|
.701**
|
|
7.RP
|
|
.051
|
-.372**
|
.575**
|
.400**
|
-.110*
|
.711**
|
1.000
|
.638**
|
-.382**
|
.728**
|
.826**
|
.730**
|
.720**
|
.925**
|
.891**
|
|
8.PF
|
|
-.056
|
-.298**
|
.551**
|
.409**
|
-.130*
|
.869**
|
.638**
|
1.000
|
-.328**
|
.615**
|
.509**
|
.417**
|
.584**
|
.608**
|
.616**
|
|
9.BP
|
|
.043
|
.144**
|
-.314**
|
-.196**
|
.016
|
-.303**
|
-.382**
|
-.328**
|
1.000
|
-.341**
|
-.285**
|
-.257**
|
-.343**
|
-.325**
|
-.110*
|
|
10.GH
|
|
-.029
|
-.332**
|
.562**
|
.373**
|
-.071
|
.681**
|
.728**
|
.615**
|
-.341**
|
1.000
|
.483**
|
.390**
|
.976**
|
.581**
|
.687**
|
|
11.VT
|
|
.199**
|
-.276**
|
.408**
|
.311**
|
-.126*
|
.554**
|
.826**
|
.509**
|
-.285**
|
.483**
|
1.000
|
.800**
|
.469**
|
.933**
|
.886**
|
|
12.SF
|
|
.206**
|
-.261**
|
.355**
|
.264**
|
-.097
|
.470**
|
.730**
|
.417**
|
-.257**
|
.390**
|
.800**
|
1.000
|
.376**
|
.848**
|
.817**
|
|
13.RE
|
|
-.013
|
-.319**
|
.523**
|
.343**
|
-.076
|
.649**
|
.720**
|
.584**
|
-.343**
|
.976**
|
.469**
|
.376**
|
1.000
|
.564**
|
.669**
|
|
14.MH
|
|
.129*
|
-.336**
|
.509**
|
.368**
|
-.124*
|
.677**
|
.925**
|
.608**
|
-.325**
|
.581**
|
.933**
|
.848**
|
.564**
|
1.000
|
.935**
|
|
15.QOL
|
|
.143**
|
-.354**
|
.499**
|
.355**
|
-.135*
|
.701**
|
.891**
|
.616**
|
-.110*
|
.687**
|
.886**
|
.817**
|
.669**
|
.935**
|
1.000
|
|
Edu: education level; Hmi: Household monthly income;Mar:Marital status; EMH:Elderly Mental Health, PF:Pysical functioning,RP: role-physical; BP:bodily pain; GH:general health;VT: vitality ;SF: social functioning; RE:role-emotional;mental health (MH);QOL:Total score of quality of life
*p < 0.05, **p < 0.01.
Latent profile analysis
Table3 provides the fit indices for the LPA models. Two- and three-class models both had significant LMR and BLRT results at p <0.05. However, the three-class solution provided a better fit than the two-class model, as AIC and BIC for the former were lower, while also showing a good value of Entropy. Therefore, the three-class model was selected as most appropriate.
Table 3 Model fit indices for one- to five-profile pattern of Mental Health dimensions and profile prevalence (%) of LPA
Profiles
|
m
|
Log(L)
|
AIC
|
BIC
|
aBIC
|
Entropy
|
LMR
|
BLRT
|
Category probability (%)
|
1
|
10
|
-5452.36
|
10924.72
|
10963.30
|
10931.58
|
|
|
|
|
2
|
16
|
-4500.29
|
9032.58
|
9094.31
|
9043.55
|
0.984
|
<0.01
|
<0.01
|
78.03/21.98
|
3
|
22
|
-4203.76
|
8451.51
|
8536.39
|
8466.59
|
0.952
|
<0.01
|
<0.01
|
61.29/22.63/16.08
|
4
|
28
|
-3992.92
|
8041.83
|
8149.85
|
8061.02
|
0.935
|
0.0665
|
<0.01
|
43.5/32.31/11.28/12.91
|
5
|
34
|
-3877.53
|
7823.07
|
7954.23
|
7846.37
|
0.932
|
0.4579
|
<0.01
|
24.86/38.12/15.70/9.20/12.14
|
Note. The values in the LMR and BLRT columns are the p values related to LMR and BLRT in comparing fit between models. m = the number of free parameters;AIC = Akaike information criterion; BIC = Bayesian information criterion; aBIC = adjusted Bayesian information criterion; LMR = Lo-Mendell-Rubin;BLRT = Bootstrapped Likelihood Ratio Tests;
As shown in Table 4, the probabilities of Profiles 1, 2 and 3 of the three-profile model were 98%, 97% and 99.9%, respectively. These indices suggested a good discriminability and reliable classification of the three-profile model.
Table 4 Average latent profile probabilities for most likely profile membership (row) by latent profile (column)
Profile
|
1(n=217)
|
2(n=77)
|
3(n=56)
|
1
|
0.98
|
0.02
|
0.000
|
2
|
0.03
|
0.97
|
0.004
|
3
|
0.00
|
0.001
|
0.999
|
Note. The columns refer to latent class, and the rows refer to most likely profile membership.
The scores of the three potential categories of mental health of empty nest elderly are as follows(Figure1, Table5): Profile 1 was the group with low ego, emotion, adaptive capacity, interpersonal communication, and cognitive function. The participants who possessed this profile comprised 61.3% of the sample. All the dimensions are at a lower level. We named this profile “low mental health.” Profile 2 was the group with a moderate level of ego, emotion, adaptive capacity, interpersonal communication, and cognitive function.We named this profile “moderate mental health” . This group comprised 22.6% of the sample. Profile 3 was the group with high level of ego, emotion, adaptive capacity, interpersonal communication, and cognitive function.We named this profile“high mental health,” and it comprised 16.1% of the sample.
Table 5 Mean, standard deviation, and normalized score for mental health dimensions of the three profiles
Dimension
|
Class1
|
Class2
|
Class3
|
Normalized score
|
Ego
|
18.47± 3. 61
|
23.74± 6.44
|
32.50± 2.68
|
35.42±5.70
|
Emotion
|
32. 66 ± 3. 42
|
38. 10 ± 6.49
|
46.41± 3.10
|
45.52±8.69
|
Adaptive capacity
|
43. 68 ± 4. 24
|
49. 28 ± 5.59
|
57.85± 3.64
|
56.01±9.49
|
Interpersonal communication
|
16. 672± 3. 37
|
22. 11± 6.65
|
30.98±2.87
|
30.27±6.16
|
Cognitive function
|
17. 91± 3. 68
|
22. 76± 4. 44)
|
29.88± 3.00
|
26.36±5.46
|
Age, gender, marital status, degree of education, and household monthly income effect on the best-fitting latent profile of mental health’s five dimensions
Gender, age, marital status, degree of education, and household monthly income were the independent variables; three potential categories of mental health were the dependent variable; and multinomial logistical regression was used to verify the significant factors that predicted potential categories of mental health, and take the Class1 as the reference group. The results of the three-step approach showed that when compared to the reference group, age, degree of education and marital status help to predict the potential categories of mental health, while other variables have no significant effect on the potential categories of mental health among empty-nest older adults, as shown in Table 6.
Table 6 Multinomial logistical regression results of demographic data on the three-profile model
Variable
|
|
|
Class2
|
|
|
Class3
|
|
|
|
β
|
SE
|
β/SE
|
P
|
β
|
SE
|
β/SE
|
P
|
Gender
|
-0.68
|
0.35
|
-1.92
|
0.06
|
-0.81
|
0.50
|
-1.62
|
0.11
|
Age
|
-0.08
|
0.03
|
-2.97
|
0.00
|
-0.13
|
0.05
|
-2.68
|
0.01
|
Degree of education
|
1.26
|
0.32
|
3.99
|
0.00
|
2.57
|
0.52
|
4.99
|
0.00
|
Marital status
|
0.08
|
0.23
|
0.34
|
0.73
|
-0.78
|
0.39
|
-2.02
|
0.04
|
household monthly income
|
0.35
|
0.32
|
1.10
|
0.27
|
0.07
|
0.48
|
0.14
|
0.88
|
Comparing quality of life of mental health profiles
To examine the outcomes of the three profiles, we compared the differences between quality of life and the related dimensions of each profile on the SF-36.
Table 7 presents the comparison of SF-36 outcome means among the three profiles
|
Variable
|
low mental health
|
moderately mental health
|
high mental health
|
F
|
ηp2
|
Post hoc
|
|
M
|
SD
|
M
|
SD
|
M
|
SD
|
RP
|
62.95
|
5.26
|
70.53
|
4.98
|
75.91
|
6.72
|
149.72**
|
0.46
|
C1<C2<C3
|
PF
|
53.12
|
2.97
|
58.10
|
2.74
|
64.64
|
5.04
|
283.55**
|
0.62
|
C1<C2<C3
|
BP
|
73.58
|
13.18
|
69.27
|
11.66
|
62.57
|
16.50
|
15.58**
|
0.08
|
C1>C2>C3
|
GH
|
54.65
|
3.78
|
60.40
|
4.84
|
66.54
|
6.48
|
168.06**
|
0.49
|
C1<C2<C3
|
VT
|
59.58
|
12.02
|
69.29
|
10.60
|
76.68
|
11.12
|
57.12**
|
0.25
|
C1<C2<C3
|
SF
|
61.34
|
9.70
|
67.56
|
10.08
|
74.25
|
10.48
|
41.70**
|
0.19
|
C1<C2<C3
|
RE
|
64.81
|
4.99
|
72.47
|
6.52
|
77.86
|
8.96
|
120.63**
|
0.41
|
C1<C2<C3
|
MH
|
58.16
|
6.86
|
65.97
|
6.31
|
72.57
|
6.50
|
119.26**
|
0.41
|
C1<C2<C3
|
*p < 0.05, **p < 0.01.
PF:Pysical functioning,RP: role-physical; BP:bodily pain; GH:general health;VT: vitality ;SF: social functioning; RE:role-emotional;mental health (MH);