Introduction

The growth in both the number and proportion of older adults has become a trend of population development in many countries around the word. The World Health Organization predicts that by 2030, the number of the older people (aged 60 years and over) will increase by 400 million to 1.4 billion (Lee et al. 2019). The world’s population of older people will double to 2.1 billion by 2050 (Lee et al. 2019). This increase is occurring at an unprecedented pace, particularly in developing countries. China has become an ageing society and has a rapidly aging population (Jiao et al. 2020; Liao et al. 2020). By 2018, there were 249 million older adults (aged 60 years and over) in China, accounting for 17.9% of the total population (Huang et al. 2019). Expectations are that, by 2030, the percentage of older people in China will account for 24.6% of the world (Yin et al. 2020). Prevalence rates concerning dementia are increasing rapidly along with the accelerating trend of population aging (Makino et al. 2021; Zhang et al. 2019b). The 2015 World Alzheimer Report revealed that China had the largest share of dementia patients in that year. The number of older adults with dementia has reached 9.5 million, accounting for 40% and 20% of the total percentage of older adults with dementia in the Asia-Pacific region and the world, respectively. This number was expected to exceed 16 million by 2030 (; Zhang et al. 2019a, c). Dementia is a common condition that mainly occurs in senior citizens. One of the clinical features of dementia is a decline in cognitive functioning that is severe enough to impact activities of daily living and social functioning (Arvanitakis et al. 2019; Macoir et al. 2021), and is the main cause of disability, mortality, and care dependence in older adults (Jia et al. 2020). It will also increase the medical economic burden on the elderly (Fishman 2017), affecting equality and convenience of access to healthcare services.

Different countries guarantee equal access to healthcare services for individuals, including members of minorities, through laws, organizational structures, and other means (Orzechowski et al. 2020; Rosenlund et al. 2017; Straiton et al. 2018). Furthermore, equality and convenience of access to healthcare services is not only a major policy concern to achieve health equity in various countries (Lee et al. 2014), but also an important guarantee for achieving the goals of the global health service system. Additionally, it plays a critical role in improving the general level of health (Baghri and Ghahramani 2018). The World Health Organization highlights that good health is essential to achieve the Sustainable Development Goals (World Health Organization 2022). Therefore, equal and convenient access to healthcare services could help achieving these goals by improving the health levels of the population, strengthening universal health coverage, and reducing healthcare service inequality. With the increasing aging population, the issue of equality and convenience in access to healthcare for seniors has received considerable critical attention. Older people often have high needs for healthcare, but frequently experience obstacles accessing it owing to a number of factors (Zhang et al. 2019a). Several studies have addressed this issue by examining factors related to healthcare service utilization among senior citizens, including sociodemographic characteristics (e.g., age, gender), income, region, and health insurance (Li et al. 2018; Naz et al. 2021; Ryvicker and Sridharan 2018).

Some researchers maintain that vulnerable groups are often at a disadvantage in the utilization of healthcare services owing to the influence of their own and external environment (Orzechowski et al. 2020; Rivenbark and Ichou 2020). Older people with dementia, as a vulnerable group, have a decline in cognitive function, and their life and social functions are affected and may even lead to disability. Therefore, they may have higher healthcare needs, but there may be more factors affecting their healthcare usage than for older people without dementia. However, many studies have focused on the healthcare service utilization in nursing facilities (Gaugler et al. 2005). Some studies examined treatment and care of elderly people with dementia (Kowalska et al. 2019; Possin et al. 2019). A systematic review of patients with dementia showed that they frequently used medical services but less frequently used community services (Chu et al. 2020). Furthermore, a prospective longitudinal study reported that age, affective symptoms, and dementia state may influence healthcare service utilization in older adults with dementia (Ydstebø et al. 2015). Thus far, there has been little discussion about the healthcare service utilization among older adults with dementia, and no large-scale studies have been performed to investigate the prevalence and profiles of utilization of healthcare services among this population.

The current study aimed to identify the utilization of healthcare services among older people with dementia to ameliorate this situation. The overall purpose of this study was to identify the prevalence of utilization of healthcare services and its relevant factors among seniors with dementia. To achieve this, we set specific objectives. Firstly, we compared the prevalence of utilization of healthcare services between older adults with dementia and those without. Secondly, we explored the factors that affect the utilization of healthcare services among older adults with dementia. Therefore, the findings presented in this thesis add to our understanding of healthcare service utilization among the elderly with dementia, which should be of value to practitioners wishing to improve the health of this special population and equal access to healthcare services.

Methods

Data and sample

We used data from the Health Service Survey of Shandong Province, which was conducted in 2018. The Shandong Health Service Survey covered a total of 17 prefectures across the province, and 20 counties, 100 towns, and 200 villages were randomly selected through a multistage stratified cluster sampling method. The sampling unit was households, and 60 households were randomly selected from each sampling village. Finally, a total of 12,938 households, consisting of 35,264 individuals, were included in the sample. After obtaining verbal informed consent from interviewees, face-to-face interviews were conducted individually for all members of each selected household by trained personnel using a structured household questionnaire. After the interviews, the survey quality instructors examined the responses for each person carefully to ensure quality. In principle, respondents were required to answer all items of the questionnaire by themselves. However, those who were not at home or unable to respond were replaced by their family members who were familiar with their situation during the survey. This survey was organized by the relevant departments of the government, and the selected respondents actively cooperated with it. Therefore, the survey sample population is an excellent representation of the population aged 60 years and above in Shandong Province.

Given that our focus was on older adults, this study considered those who were aged 60 years and above, and 8847 respondents were included.

Variables

Dependent variables

Two measures of the utilization of healthcare services were used as dependent variables: (1) “Utilization of outpatient care” was defined as “visiting physicians when ill within the last 2 weeks”; (2) “Utilization of inpatient care,” was defined as “use of inpatient services when referred by doctors for hospital admission during the previous year.”

Independent variables

Based on Andersen’s model (Andersen and Newman 1973; Zhou et al. 2015), we categorized the independent variables into three types: predisposing, enabling, and need variables. (a) Predisposing variables. In the present paper, these variables include gender (male, female), age (60–69, 70–79, ≥80), marital status (married or other) and education (never attended school, primary, junior, high and above). (b) Enabling variables. We classified residence (urban, rural), health insurance (Medical Insurance for Urban Employees (MIUE) scheme, medical insurance for rural and urban residents), road distance to the nearest hospital, time to the nearest hospital. (c) Need variables. Illness in the past 2 weeks and non-communicable chronic disease (NCDs) in the past 6 months were used as measures of need.

Data analysis

The statistical package IBM SPSS Statistics for Windows version 23.0 (IBM Corp., 2015) was used to analyse the data. Regarding the general baseline characteristics, data were described by numbers and proportions. A chi-square test was performed to compare the significance of baseline characteristics and utilization of healthcare services between the participants with and without dementia. In addition, preliminary analyses were conducted using a chi-square test to check which factors were related to the utilization of healthcare services. Whether an individual had used healthcare services was then used as a dichotomous variable. A multivariate logistic regression was further employed and the variables with statistical significance were included in the analysis, to assess the explanatory factors for outpatient care and inpatient care service utilization. Statistical significance was set at the 5% level.

Results

The general baseline characteristics of the selected older adults are shown in Table 1. Among the respondents, 261 (3.0%) had dementia and 8586 (97.0%) did not (non-dementia). There were significant differences in age, marriage status, educational status, residence status, enrolment in medical insurance, illness within 2 weeks, and NCDs within 6 months before the survey between these two groups (P<0.05), but gender, road distance, and time to the nearest hospital did not differ significantly between them.

Table 1 Baseline characteristics of the participants according to their cognitive function (2018)
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Men accounted for 50.6% and 48.3% of participants in the dementia and non-dementia groups, respectively, and there was no significant difference in gender between these two groups. The dementia group aged 80 years and older accounted for 23.0% of all participants—a percentage higher than that in the non-dementia group (8.3%). The proportion of married participants in the dementia group (73.6%) was lower than that in the non-dementia group (84.0%). Approximately 46.7% of participants in the dementia group never attended school—a percentage significantly higher than that of the non-dementia group (30.8%). Participants who lived in rural areas account for 64.8% of those in the dementia group—a percentage higher than that in non-dementia group (51.2%). The enrolment rate of MIUE in the dementia group (10.7%) was significantly lower than that of the non-dementia group (22.5%), but the enrolment rate of medical insurance for rural and urban residents among the dementia group (90.0%) was generally higher than that for the non-dementia group (77.8%). The prevalence rates of illness within 2 weeks before the survey were 62.5% and 52.8%, respectively, and those of NCDs in the past 6 months among the dementia and non-dementia groups were 65.9% and 54.5% respectively. The differences in the above two indicators were statistically significant between the two groups.

Table 2 indicates the differences in utilization of healthcare services among participants. Overall, the proportion of respondents who used outpatient care and inpatient care was 40.6% and 76.9%, respectively. When comparing the utilization of healthcare services between the older people with dementia and those without, we found that the rate of outpatient care in dementia and non-dementia groups were 44.8% and 40.5%, respectively, and there was no significant difference between the two (P=0.269). The results also show that the rate of inpatient care utilization among the dementia group (80.8%) was slightly higher than that among the non-dementia group (76.7%), but the difference had no statistical significance (P=0.403).

Table 2 Comparison of utilization of healthcare service between participants with and without dementia (2018)
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We compared the rate of outpatient utilization by a chi-square test in the different subgroups of dementia (Table 3). The output shows that older adults with dementia who were married (P=0.026) and had experienced NCDs within the past 6 months (P=0.033) were less likely to use outpatient care. However, those who lived in rural areas (P=0.006) tended to use outpatient care.

Table 3 Factors associated with outpatient care utilization among participants with dementia in Shandong (2018)
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Multi-logistic regression analysis was used to find the determinants associated with the utilization of outpatient care. Older people with dementia who were married and had experienced NCDs within the past 6 months were less likely to use outpatient care. Compared with older people whose marriage status was “other,” the odds of utilizing outpatient care were 0.468 times (95% CI: 0.223–0.979) lower for older people who were married. In terms of chronic disease, the odds of utilizing outpatient care were 0.275 times (95% CI: 0.101–0.752) lower for older people who had experienced NCDs within the past 6 months than for those who had not. The seniors with dementia who lived in rural areas tended to use outpatient care. The odds of utilizing outpatient care were 2.950 times (95%CI: 1.403–6.201) higher in this group than in the urban group.

Table 4 shows the influencing factors linked with the utilization of inpatient care. A chi-square test was performed to compare the utilization of inpatient care between participants with dementia and those without; however, no factors were found to be associated with inpatient care utilization. According to the multi-logistic regression analysis, there were no explanatory factors for the utilization of inpatient care services.

Table 4 Factors associated with inpatient care utilization among participants with dementia in Shandong (2018)
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Discussion

With the change of population structure, the improvement in living standards, and the extension of life expectancy, older adults with dementia have gradually become a research hotspot. In a meta-analysis conducted in 2018, 96 previous studies were combined. The results reported that the overall prevalence of dementia among people aged 60 years and older in China was 5.3% (4.3–6.3) (Wu et al. 2018). According to a nationwide study in 2015, the overall weighted prevalence of older people with dementia was 4.22% (2.27–6.17) for the Chinese adults aged 60 years and older (Qi et al. 2021). Moreover, studies have shown that in 2013, the prevalence of dementia in China was 5.60% (3.50–7.60) for individuals aged 65 years and older (Huang et al. 2019). An observational study of older people aged ≥60 years and residing in rural areas of northern China conducted between 2011 and 2012 showed that the prevalence rate of dementia was 7.7% among 5578 enrolled study participants (Ji et al. 2015). Our findings suggest that 3.0% of participants in the survey sample had dementia. This proportion is lower than that of previously reported levels (Ding et al. 2014). This result may be explained by the fact that, in this study, dementia was self-reported, and there may be situations where people are ill with dementia but have not yet been diagnosed. Another possible explanation for this is the variation of dementia prevalence according to the geographic locations (Wu et al. 2018). Previous study had shown that there may be unknown differences in the cause of dementia across geographical locations (GBD 2019 Dementia Forecasting Collaborators 2022).

Consistent with previous reports, this study found that older adults with dementia had a higher prevalence of illness within the past 2 weeks and NCDs within the past 6 months, which indicates that they have poorer health status than those without dementia (Bickel et al. 2018). A rapid decline in cognitive and functional skills is commonly observed among older people with dementia (Hartley et al. 2017), which may increase their frustration and negatively affect their mental health. Such feelings of frustration and negative psychological emotion will further affect their physical health and ability to perform activities of daily living (ADLs) (Animasahun and Chapman 2017). As such, seniors with dementia may have higher healthcare needs than those without dementia, which is in line with previous studies (Arsenault-Lapierre et al. 2023).

In addition, according to Andersen’s model (Andersen and Newman 1973), the utilization of healthcare services is based on healthcare needs. Our findings reveal that the rate of outpatient care and inpatient care utilization among older people with dementia is slightly higher than that of older people without dementia, which indicates the unequal needs for healthcare between the two subgroups. Our study shows that older adults with dementia are more likely to have higher healthcare needs than those without dementia. This indicates that it is terribly important to explore the influencing factors for the higher prevalence of utilization of healthcare services in older people with dementia and to formulate appropriate plans to meet the needs of such a vulnerable and special group.

An interesting finding in this study is that the seniors with dementia who had experienced NCDs within the past 6 months experienced statistically lower utilization of outpatient care than those who had not experienced NCDs, which is different from other studies conducted with older people in general (Kim and Lee 2016). There are two possible explanations for such result. First, as a vulnerable population lacking ADLs, the health status of older people with dementia is more likely to be affected by NCDs than that of others, and this group is more likely to experience obstacles to healthcare utilization. Second, older adults with dementia who have NCDs receive much more social support (Cohen et al. 2020), which not only reduces the incidence of other ailments (such as trauma, falls, etc.), but also improves the convenience of at-home care services, reducing the necessity for outpatient care. As a result, the other needs for healthcare services for older adults with dementia who are chronically ill are reduced. Further studies on seniors with dementia should be conducted to verify this finding.

Similar to previous studies, the present study reveals that older adults with dementia from rural areas tend to access outpatient care (Wu et al. 2018). According to the characteristics of rural China, the findings should, therefore, provide an impetus to strengthen the health publicity and education of the older adults with dementia and their families to improve their health awareness. A special and person-centred care supplement to existing schemes (e.g., family physicians) or a combination of community care and medical assistance policies targeting older people with dementia may be effective to meet their healthcare needs when required. It is also noted that older adults with dementia whose marriage status is “other” were far more likely to use outpatient care in this study. It is possible that this result is due to the fact that these individuals receive less partner support and consider the serious consequences (e.g., disability) of not using healthcare services when required. Furthermore, no statistically significant factors were found in the utilization of inpatient care. Further research will have to be conducted on this aspect.

There are also several limitations in this study. First, the sample size of older adults with dementia was too small to fully represent the healthcare service usage status of this population group in China. Second, the information about dementia status and healthcare service utilization was self-reported, leading to the possibility of recall bias and a low diagnosis rate. Third, a period of 2 weeks was used when measuring the utilization of outpatient care. However, it is inevitable that issues related to disease course and seasonal variation will arise, particularly with the development of acute diseases. Fourth, in terms of the depth of the study, we employed a cross-sectional design to explore the healthcare service utilization among older adults. Therefore, the relationship between identified factors and the utilization of healthcare services cannot be interpreted as cause and effect, and this study could only provide the possible influencing factors for healthcare service utilization.

Older people with dementia, as a vulnerable group, may have higher healthcare needs, and the factors affecting the utilization of healthcare may be more severe than among older adults without dementia. Thus far, however, there have been minimal studies about healthcare service utilization among older adults with dementia. The current study identified the utilization of healthcare services among older people with dementia and ameliorated this situation. Furthermore, this study identified the prevalence of utilization of healthcare services and its relevant factors among this special population. The findings presented in this thesis could add to our understanding of prevalence of the utilization of healthcare services and its associated factors. That is very important for further developing targeted interventions to meet the needs for such a vulnerable and special population.

Conclusion

This study reveals that older adults with dementia have poorer health status and higher healthcare needs than those without dementia. The findings indicate that the utilization of outpatient care for older adults with dementia could be affected by marriage status, residence, and NCDs. No statistical factors were found to affect the utilization of inpatient care. Comprehensive health publicity and education and a combination of community care and medical assistance targeting older adults with dementia is essential to further increase healthcare service utilization when required.