Multiple strategies were developed to alleviate caregivers’ burdens, including community-based service, popular in Western countries. On the other hand, a home-based service model is more acceptable in the Asian community. Additionally, the deep-rooted filial piety and the sense of obligation for caring for elderly family members16 make hiring a foreign caregiver the favored option in Chinese culture.
Supported by the findings in this study, both home-based service and foreign caregiver provided a significant reduction in primary caregivers’ burden. Currently, there are many home-based services for people with dementia similar to the model in Taiwan worldwide. The Maximizing Independence (MIND) at Home is a home-based dementia care program in the United States that offers specific needs to the person with dementia and their caregiver. In a prospective study, the caregivers showed a reduced burden (ZBI score) and distress after receiving 18 months of the MIND at Home program17. In Singapore, the Hua Mei Dementia Care System (HMDCS) that provides multidimensional care, including caregiver support, also improves ZBI score in 38% of the caregivers18. Meta-analysis has shown home-based service, in either dyadic or carer-directed form, can reduce caregivers’ burden with physical activity programs19,20, education and skill training (Williams et al., 2018), support and counseling20.
A study conducted in Northern Taiwan showed that the ZBI score was higher in families with a foreign caregiver than the families without (median ZBI score: 38.5 vs. 34, p = 0.033)21. The authors suggested that patients with foreign caregivers were older and had more severe neuropsychiatric symptoms than patients without foreign caregivers. Although the control and resource-utilized groups in the present study were relatively matched based on global CDR, gender, and age, the pre-ZBI score in the foreign caregiver group was also higher than the control group (mean pre-ZBI score 24.97 vs. 36.57). The breakdown of global CDR by points showed that the foreign caregiver group had a higher percentage of patients with higher CDR scores (CDR ≥ 2: 42.9% vs. 20.3%); this finding echoes with Lin et al. inferring the severity of dementia contributes to a more significant burden. To take a step further, in the six-month follow-up, the families hiring foreign caregivers showed a significant burden reduction, ΔZBI − 17.99 in the foreign caregiver group compared to ΔZBI of 1.23 in control. A qualitative study conducted in Singapore found caregivers’ relief mostly came from the physical support brought by the hired foreign helper, such as cooking, feeding, and bathing16.
The caregiver burden increased in the community-based services group, which was an unexpected finding. In a previous study, Sussman et al. found that the community-based services (adult day program, institutional respite services, geriatric clinic services, or emotional support services), caregivers’ burden has an inverse relationship to the frequency of day program attended22. An increase in day program attendance in people with dementia tends to relieve caregivers’ burden. A study conducted in sixteen specialized dementia community-based service providers in Maryland, U.S.A. found that offering specialized medical needs attributes to 26% of the changes in ZBI score23. Several possible explanations of conflicting findings include the heterogeneity of the resource type and diverse use frequency in the community-based service group. Factors related to caregivers’ health, which could be a possible confounding variable, were also not considered in the current study.
Yet another possible explanation for the lack of improvement in ZBI score in the community-based service group may be the difference in clinical severity in this group. As mentioned above, participants in the home-based services and foreign caregiver groups have a higher baseline CDR score (21.1% and 42.9% with CDR ≥ 2, respectively), suggesting more severe dementia symptoms, loss of mobility, and a higher level of dependence. On the other hand, the participants in the community-based service group tend to be more mobile, thus causing a higher burden on the caregivers because of behavioral problems but not physical handicaps24. The burden attributed to behavioral symptoms may be less directly responsive to care resources. Future studies can elucidate this further by accounting for mobility when matching the groups.
The subgroup analysis compares three different community-based services to the control group, though not statistically significant. The community elderly stations and the community dementia care center tend to have decreased burden and a higher percentage of not-aggravated ZBI scores than the control group. However, the increased burden was observed in the daycare group. One possible explanation is that care attendants have relatively low care ability and familiarity with dementia patients in daycare centers than community dementia care centers. Other factors that may affect the outcome; the definition of community-based services varies in different studies, leading to the group’s heterogeneity. In addition, the un-uniformed subgrouping method (for example, subgroup by the nature of the services such as medical, emotional, or respite support, or subgroup by type of institution such as daycare center, dementia specialized center, or community center) causing inherited differences in the subgroup analysis in each study and thus its’ external validity suffers.
Several limitations exist in the current study. One common disadvantage is the risk of loss to follow-up; however, this is mitigated by shortening the length of data collection, but doing so generates issues with insufficient observation time. Additionally, the retrospective cohort study’s nature renders unknown confounding factors during data collection, such as participants’ motility status, behavioral and psychological symptoms of dementia, and caregivers’ health conditions.