This study conducted a structural equation modeling analysis to verify the research hypotheses presented and the analyzed goodness of model fit was shown like in <Table 7> below.
In the goodness of model fit, NFI, IFI, and CFI all appeared 0.9 or higher, and so the model was judged to be appropriate.
The results of parametric estimation for verifying the research hypotheses appeared like in <Table 8> below.
<Table 7> Goodness of model fit of the structural model
Index of fit NFI* IFI* CFI*
Standard >.90 >.90 >.90
Goodness of fit 0.905 0.920 0.918
* NFI(Normed fit index): is an index representing how much the proposed model has improved compared to the basic model. If it is generally 0.90 or higher, it is regarded as acceptable.
* IFI(Incremental fit index): has a value from 0 to 1. If it is 0.9 or higher, it is judged as a good fit.
* CFI(Comparative fit index): was developed from the perspective of indicating parameter and distribution of parent population to complement NFI. has a value from 0 to 1. If it is 0.9 or higher, it is judged as a good fit.
<Table 8> Result of parametric estimation in structural model
B S.E. C.R. P β
Patient
state → Care
activity 5.172 .859 6.022 *** .504
Patient
state → Care
burden 1.121 .170 6.580 *** .499
Patient
state → Caregiver
depression .069 .021 3.291 *** .316
Care
activity → Care
burden .231 .109 2.123 .034* .250
Care
activity → Caregiver
depression .028 .043 1.781 .076 .192 Care
burden → Caregiver
depression .500 .061 8.132 *** .518
*p<.05 ***p<.001
As a result of analysis, the impact of patient state on care activity was β=.504***, which appeared significant in the positive (+) direction. And the impact of patient state on care burden was β=.499***, which appeared significant in the positive (+) direction. Also the impact of patient state on depression was β=.250, which appeared significant in the positive (+) direction. In other words, it can be known that if the patient state is worse, the caregiver activity and burden get higher and the depression becomes higher. Therefore, the Research Hypotheses H1-2, H1-3 and H1-1 presented in this study were adopted.
And the impact of care activity on care burden was β=.316***, which appeared significant in the positive (+) direction. In other words, it can be
known that the more the care activity, the higher the care burden.
Therefore, the Research Hypothesis H1-4 presented in this study was adopted.
In addition, the impact of care burden on depression was β=.518***, which appeared significant in the positive (+) direction. In other words, it can be known that the more the care burden, the higher the depression.
Therefore, the Research Hypothesis H1-6 presented in this study was adopted.
But the impact of care activity on depression was β=.192, which appeared not significant. Therefore, the Research Hypothesis H1-5 presented in this study was rejected.
The results so far can be represented like in <Figure 6> below.
SMC: Care activity(.254), Care burden(.507), Caregiver depression(.890)
<Figure 6> Result of direct effect
And the results drawn by verifying the mediating effect hypotheses presented in this study with Sobel test are like in <Table 9> below.
<Table 9> Result of the mediating effect analysis
Pathway z p Result
Patient state
→ Care activity
→ Caregiver depression
.647 .517 Rejected
Patient state
→ Care burden
→ Caregiver depression
5.138 .000*** Adopted
Care activity
→ Care burden
→ Caregiver depression
2.052 .040* Adopted
**p<.01 ***p<.001
As a result of analysis, the mediating effect of care burden between patient state and depression was z=5.138***, which had a significant mediating effect. And the mediating effect of care burden between care activity and depression was z=2.052*, which had a significant mediating effect. But the mediating effect of care activity between patient state and depression was z=0.647, which was not significant in mediating effect.
Therefore, the Research Hypotheses H2-2 and H2-3 presented in this study were adopted and H2-1 was rejected.
As a result of verifying the moderating effect of social activity in structural routes of dementia elderly patient state, caregiver activity,
burden, and depression, the goodness of model fit appeared like in <Table 10> below.
<Table 10> Goodness of fit of the moderating effect model
Index of fit NFI* IFI* CFI*
Standard >.90 >.90 >.90
Goodness of fit .887 .916 .913
* NFI(Normed fit index): is an index representing how much the proposed model has improved compared to the basic model. If it is generally 0.90 or higher, it is regarded as acceptable.
* IFI(Incremental fit index): has a value from 0 to 1. If it is 0.9 or higher, it is judged as a good fit.
* CFI(Comparative fit index): was developed from the perspective of indicating parameter and distribution of parent population to complement NFI. has a value from 0 to 1. If it is 0.9 or higher, it is judged as a good fit.
As IFI and CFI appeared 0.9 or higher in the goodness of model fit, the model was judged to be appropriate.
D. Analysis of Moderating Effect
1. Social Support’s Moderating Effect
The results from the parametric comparative analysis in multiple group analysis to verify the moderating effect of social support presented in this study appeared like in <Table 11> below. At this time, to make social support moderating variable, we recoded the group of less than median
value as ‘low group’ and the group of more than median value as ‘high
low 3.922 1.106 3.545 *** .439
1.302
high 6.083 1.240 4.907 *** .559
Patient
low .188 .177 1.061 .289 .163
.062
high .174 .088 1.977 .048* .286
Care
activity → Care burden
low .069 .033 2.119 .034* .258
1.546
high .068 .030 2.297 .022* .354
Care
activity → Caregiver depression
low .055 .022 2.507 .012* .425
1.268
high .014 .015 .891 .373 .144
Care
As a result of analysis, it appeared that the moderating effect of social support was not significant at C.R<±1.96 in all routes between patient state, care activity, care burden, and depression. Therefore, the Research Hypothesis H3-1, presented in this study was rejected. The analytical
results can be shown by group of social support like in <Figure 7> below.
<Figure 7> Result of the moderating effect of social support
2. Social Activity’s Moderating Effect
The results from the parametric comparative analysis in multiple group analysis to verify the moderating effect of social activity presented in this study are shown like in <Table 12> below. At this time, to make social activity moderating variable, we recoded the group of less than median value as ‘low group’ and the group of more than median value as ‘high group.’
low 2.523 1.029 2.453 0.014* 0.390
2.481*
high 6.776 1.371 4.941 *** 0.487
Patient
state → Care burden
low 1.680 0.253 6.650 *** 0.635
2.855*
high 0.727 0.219 3.326 *** 0.393
Patient
state → Caregiver depression
low 0.257 0.189 1.363 0.173 0.224
0.369 high 0.250 0.120 2.089 0.037* 0.435
Care
activity → Care burden
low 0.067 0.034 1.971 0.048* 0.278
0.034 high 0.051 0.22 2.299 0.022* 0.387
Care
activity → Caregiver depression
low 0.023 0.019 1.205 0.228 0.128
0.061 high 0.024 0.014 1.783 0.075 0.134
Care
burden → Caregiver depression
low 0.435 0.077 5.663 *** 0.830
0.724 high 0.523 0.093 5.605 *** 0.984
*p<.05 **p<.01 ***p<.001
As a result of analysis, in the impact of patient state on care activity, social activity’s moderating effect appeared (C.R=2.481*). In this route, the group of high social activity was β=.487***, which was significantly higher than the group of low social activity (β=.390*). In other words, the impact of patient state on care activity was found to be greater than the group of high social activity.
And in the impact of patient state on care burden, social activity’s moderating effect appeared (C.R=2.855*). In this route, the group of low social activity was β=.635***, which was significantly higher than the group of high social activity (β=.393***). In other words, the impact of patient state on care burden was greater in the group of low social activity.
Therefore, the Research Hypothesis H3-2, presented in this study was partially adopted. The analytical results can be shown by group of social activity like in <Figure 8> below.
<Figure 8> Result of the moderating effect of social activity
Ⅴ. DISCUSSION A. Summary and Discussions
This study was conducted to identify the mediating effect of care activity and burden and the moderating effect of social support and social activity in the relationship between dementia patient state and caregiver depression. Hypotheses were tested with structural equation modeling and the tested results were compared with the findings from the precedent studies as follows:
1. Considerations on Direct Effect
The precedent studies have reported about the relationship between dementia patient state and depression that care situations like dementia elderly’s Activities of Daily Living (ADL) and Problem Behavior (BPSD) and family caregiver’s coping style and social support had an impact on family caregiver depression (Ma and Kim, 1995; Kim, 2002) and that the higher the dependence in dementia elderly’s activities of daily living and the worse the problem behavior, the higher the family caregiver’s depression or stress (Brodaty and Luscombe 1998; Meshefedjian et al., 1998). As can be seen in Jang(2013) or Hong(2016) who reported a similar relationship between dementia patient state and depression, caregiver depression is influenced by dementia patient state. Such a relationship was also drawn from this study.
As reported in many precedent studies on the relationship between burden and depression in dementia patient caregivers (Ryu, 2017, Hong, 2017, Park, 2015), the variables that had the biggest impact on depression were subjective health condition, care period, occupation, self-efficacy, quality of marital relationship before caring, and care burden prior to social support (Park, 2015), and the correlation between dementia patient caregiver’s care burden and depression is high, but both cannot be said as the same concept, and there are different opinions about the directivity, and unlike the care burden that individuals feel because they care for the dementia patients, depression is regarded as a psychological construct that is influenced by care situations including care burden and other different states and care burden is seen as a predictor of depression (Ryu, 2017).
Also, considering Pearlin(1990) and Tennstedt et al.(1989) arguing that care burden had an impact on depression, the same results could also be found in this study.
As can be seen in studies (Kwon et al., 2002) that patient state causes care activity and studies (Song et al. 2013; Bae et al, 2006) that patient state had an impact on care burden, such care activity or burden is associated with the symptoms that dementia patients show. The Ministry of Health and Welfare(2009) reported that among dementia patient’s declined cognitive function, deteriorated activities of daily living, and problem behavior, patient’s problem behavior had the biggest impact on dementia caregiver’s burden, and restlessness and aggressive behavior which are shown in the group of behavioral and psychological symptoms aggravates the relationship with caregiver and the aggravated relationship in turn causes more severe behavioral problems from the patients who are
cared, which is a vicious cycle (Rachel et al., 2005). In fact, dementia patient’s unregulated behavioral and psychological symptom like aggression is the cause why nursing facilities refuse them to admit, which aggravates caregiver burden. Song et al.(2013) stated that dementia severity is judged as declined cognitive disorder, behavioral and psychological symptoms, and activities of daily living, and depending on dementia severity, main caregiver’s time to take care of patients increases and care burden also increases. Compared with the findings from such precedent studies, this study is in the same context with such studies.
Precedent studies present various causes of care burden that dementia patient caregivers feel, but among which, care activity is emphasized. Song et al.(2013) maintained that in case of dementia severity, its severity increases main caregiver’s time to take care of patient and increases care burden, too. Lee et al.(2008) claimed that if the effort and time to take care of dementia elderly increases due to dementia elderly’s problem behavior and dependence, caregivers feel considerable care burden in physical, psychological, and economic aspects. Multiple precedent studies on care burden stated that care period has an impact on care burden and especially mentioned the relationship between role constriction and care period, as one of the care burden factors that dementia elderly caregivers feel strongly. Due to role constriction that threatens the existing ordinary lives, caregiver loses his self-esteem, which leads to anger at the patient and the burden from role constriction aggravates as the time to take care increases and care period cannot be separated in understanding the care burden. The more the care period, the care burden increases, and if one should take care of a patient all day long, care burden is great, and care
burden lessens if sharing the burden rather than if taking care of a patient alone, which shows a close relationship between care period and care burden (Kwon et al. 2015). When compared with the findings from this study based on the reports from such precedent studies, the explanations about the relationship between dementia patient caregiver’s care activity and care burden are in the same context.
However, Park et al.(2005) claimed that as caregivers have to be with dementia elderly all day long, they are socially isolated and their physical health is aggravated and at the same time, care burden increases and depression gets worse. Compared with Kim(2000) or Bae et al.(2018) who reported that caregiver’s activity has an impact on depression, this study shows a different context in that insignificant results were drawn in this study.
2. Considerations on Mediating Effect
As a result of analyzing the mediating effect of care activity and care burden that this study presented as core research hypotheses based on different research findings presented in precedent studies, it was found that the mediating effect of care activity between patient state and depression was not significant, but care burden showed a significant mediating effect in the relationship between dementia patient state and caregiver depression and the relationship between care activity and depression, which showed differentiation from the precedent studies. The moderating effect of social support did not appear in all routes between patient state, care activity, care burden, and depression, but the moderating effect of social activity
appeared significant in the impact of patient state on caregiving activity and the impact of patient state on care burden. This study result shows differentiation from the precedent studies.
3. Considerations on Moderating Effect
That the moderating effect of social support did not appear in this study well represents the care characteristics of dementia patients characterized by chronic stress (Lee, 2003) and is different from the usefulness of social support that appeared in the high level of stressful situations (Clyburn, 2000), which is noteworthy. This means that Korean caregivers use emotional coping styles a lot than American or Canadian family caregivers in stressful situations, which is explained by many scholars (Lee and Kim, 2000; Lee et al., 2002).
The role of social support needs to be analyzed by classifying to subject’s short-term stressful situation and constant stressful situation.
Also in judging the social support by subjective perception part, more structured and detailed testing needs to be attempted by developing definite tools and setting various research subjects and variables. Also as argued by Kim(2001) that low voluntary motivation acts as a care burden determinant, regarding the part that in the moderating effect of social activity, care activity increases more and care burden increases less in the group of high social activity frequency than in the group of low social activity frequency, the relationship between support motive and care activity needs to be examined more specifically.
The policy direction for dementia population is to create an environment
where patients can get along with their families or normal people rather than isolating them into a facility (Hong, 2017), while calling for the changes from disease treatment-centered medical paradigm to care in human correlations paradigm (Kim, 2010). Such direction is in the same context with the policy directions for dementia, for it was verified in this study that caregiver’s social activity has a moderating effect in increasing the caregiving activity and lowering the care burden.
Social participation activity acts positively in forming a recognition that one thinks oneself as valuable for the society, which plays a role in reducing the negative result like depression.
Social relationship is above all important as it helps keep self-identity and maintain living patterns (Atchley, 1999). But social relationship is formed by social participation activity, which consequentially contributes to keeping self-identify and maintaining living patterns. Therefore social participation activity acts positively in maintaining internal and external permanence, which influences reducing depression (Hooyman & Kiyak, 2008).
Based on the analytical results above, we could draw the following suggestions.
First, to reduce the depression of dementia patient caregivers, the caregivers will have to be supported and attended constantly and positively to improve patient state although dementia is an irreversible disease, for such support and attention has a significant impact on patient state and caregiver burden.
Second, given that care activity and care burden play a mediating role in
the relationship between dementia patient state and caregiver depression, the strategic plans for reducing caregiver depression need to be found from care activity and care burden. In other words, to ensure that caregivers involve in care activity more easily and subsequently reduce the care burden, specific support plans including training and direct service provision by care activity needs to be established.
Third, given that social activity has a positive moderating effect in the relationship between dementia patient state and caregiver’s activity or burden and depression, it is necessary to find the strategic plans for reducing the caregiver depression from their social activities. In other words, the structural devices that are effective and available should be established so that caregivers can involve in social activity constantly and stably.
Despite such findings, this study has limitations in generalizing the findings in that it did not target various dementia patient caregivers and did not consider various variables that could predict or cause caregiver depression.
The limitations of this study are as follows:
First, this study has limitations in that as it is based on CREDOS data, it could not use social support and social activity suitable for the intention of this study properly. That is to say, social support, used in this study contained three dimensions: care, moral support, and instrumental support, and social activity contained two dimensions: period and frequency. But the concepts social support and social activity can be more comprehensive and
accordingly measurement methods and scales can also vary. Despite the necessity of accurate measurement tools that can be explanatory of dementia patient caregiver’s social support and social activity specifically, this study could not help but use the social support and social activity questions provided by CREDOS. Therefore, it is considered that further studies need to develop the measurement tools that can predict social support and social activity for dementia elderly caregivers exactly. To this end, Delphi method which is based on the survey of experts, item fit analysis, and factorial analysis and reliability survey that can ensure the validity will have to be used.
Second, as this study is based on the CREDOS data, our analysis of dementia patient caregiver’s social activity was conducted centering on non-economic activities like religious gathering, social gathering, leisure, culture, and sports-related group meeting, reunion, hometown alumni, clan gathering, volunteer work, party meeting, civic group meeting, and interest group meeting. But based on the existing studies that economic activity based on labor reduces depression, there is a need to analyze the economic activity as well as non-economic activity.
Third, this study did not examine the mechanism between social activity and depression sufficiently. The existing studies present that social participation activity has an impact on depression through self-esteem, ego resiliency, and social integration. It is hoped that meaningful results can be drawn by conducting further studies that can reflect such mechanism
Third, this study did not examine the mechanism between social activity and depression sufficiently. The existing studies present that social participation activity has an impact on depression through self-esteem, ego resiliency, and social integration. It is hoped that meaningful results can be drawn by conducting further studies that can reflect such mechanism