Impact of dementia on the trajectories of quality of life in older adults

Česká verze

Authors: H. Kisvetrová ¹; D. Školoudík ²; R. Herzig ³; M. Vališ ³; B. Jurašková ⁴; J. Tomanová ¹; R. Vaverková ¹; K. Langová ¹ ; Y. Yamada ⁵
Authors place of work: Centrum vědy a výzkumu, Fakulta, zdravotnických věd, UP v Olomouci, Česká republika ¹; Neurologická klinika FN Ostrava, Česká republika ²; Neurologická klinika LF UK a FN Hradec Králové, Česká republika ³; III. interní gerontometabolická klinika, FN Hradec Králové, Česká republika ⁴; Center for Medical Education and, Internationalization, Graduate School, of Medicine, Kyoto University, Japan ⁵
Published in the journal: Cesk Slov Neurol N 2020; 83/116(3): 298-304
Category: Původní práce
doi: https://doi.org/10.14735/amcsnn2020298

Summary

Aim: To assess the quality of life (QoL) and the factors affecting QoL in patients with dementia (PwD) and without dementia, and if dignity belongs to these factors. To define predictors of QoL change over 2 years.

Participants and Methods: The set consisted of 294 PwD (37.1% males; age 79.6 ± 7.5 years; MMSE 22.7 ± 1.7) and 329 patients without dementia (30.1% males; age 72.7 ± 7.0 years; MMSE 29.2 ± 1.3). Prospective longitudinal design (three measurements over 2 years) was used. The questionnaire set included Czech versions of standardized tools for QoL, depression, dignity, attitudes towards aging, physical fitness, self-sufficiency, pain, and a set of socio-demographic data. Paired t-test, chi-square test, Shapiro-Wilk test, Durbin-Watson test, and multivariate linear regression were used for the statistical analysis.

Results: Depression influenced QoL in both groups of respondents. PwD had a higher QoL also associated with a more positive assessment of dignity, better self-sufficiency (all P < 0.001), and a more positive attitude towards aging (P = 0.011). QoL got worse during 2 years only in PwD (P < 0.001). Predictors of deterioration in QoL were male gender (P = 0.021), loneliness ≥ 8 h per day (P = 0.001), partner-free life (P < 0.001), lower frequency of visits (P = 0.039), and higher QoL at baseline (P < 0.001).

Conclusion: Dignity belongs to significant factors of QoL in PwD. Social relationships and social engagement are essential for maintaining the QoL long-term.

Keywords:

dementia – Quality of life – depression – aging – dignity – attitude – social involvement

Introduction

There are currently around 50 million people with dementia in the world, and this number is projected to rise to 152 million by 2050. The prevalence of dementia increases exponentially at the age of over 60 and varies between regions. Estimates range from 4.6% in Central Europe, including the Czech Republic, to 8.7% in North Africa and the Middle East [1,2]. Dementia is thus a global social and health phenomenon, with an impact on society as a whole. Dementia syndrome is caused by neuro-degenerative disorders (in degenerative dementia) and other aetiologies (e.g. post-traumatic or vascular dementia) that affect cognitive abilities, leading to a progressive loss of self-sufficiency in daily life and of the ability to engage in social activities. All this has a negative impact on the quality of life of older adults [3]. The initial stage of dementia is characterized by memory impairment, which is mainly true for Alzheimer's disease [4], communication disorders, and impaired executive or visual-spatial functions, which is characteristic of frontotemporal dementia, vascular, and dementia with Lewy bodies. However, the individual is able to realize his or her illness, and this often leads to uncertainty and mood swings (depression, anxiety). The individual gains reassurance and certainty by observing a regular daily regimen and accustomed rituals. The performance of the complex cognitively focused daily activities of an individual experiencing health issues with negative consequences for their quality of life may also be affected. Promoting the quality of life of older adults in the early stages of dementia has therefore become one of the key objectives of healthcare [5,6].

Quality of life is a multidimensional construct, based on an individual's subjective experience with his/her own life and objective criteria in the context of the culture and values of the society in which he/she lives [7]. In recent years, research has focused on self-assessment of quality of life and the factors that affect it in older adults with or without dementia [8-11]. In older adults with dementia, a reduced quality of life is often associated with the loss of functional ability and self-sufficiency in daily life activities (ADL) [12], the fear of falling [13], restriction of social participation [14,15], chronic pain [16], and negative attitudes towards ageing [17]. Also, the depression that is often found in older adults is considered to be a significant variable affecting the quality of life of people with dementia [18]. The above factors usually coincide with those found among patients without dementia [19]. Until now, however, when the trajectory of the quality of life has been examined, the assessment of the dignity among older adult has not been included among the variables.

The aim of our study was to work out an assessment of the quality of life and the factors that affect it among patients in the early stages of dementia and those without dementia, and whether dignity is among these factors, and, additionally, to define predictors of changes in the quality of life over the course of two years.

Methods

Respondents

The research group consisted of two groups of respondents. The first group consisted of patients in the early stage of dementia who met the inclusion criteria: 1) age ≥ 60 years; 2) diagnosed with any type of dementia in the early stage (diagnosis according to MSK 10: F00, F01-F03) with the Mini Mental State Examination (MMSE) score of 20-25 points; 3) contact with the family member providing care at least once a week. The respondents were approached through neurological and geriatric outpatient departments, where they were being treated for dementia. The second group consisted of patients without dementia who met the inclusion criteria: 1) age ≥ 60 years, 2) without a diagnosis of dementia; 3) the MMSE score of 26-30 points. The patients were approached through general practitioners’ surgeries. The exclusion criteria for both groups of patients were: 1) permanent institutional care; 2) complete immobility; 3) a severe mental disorder (schizophrenia, bipolar disorder); 4) terminal stages of the disease.

The study took place in the years 2017–2019 in three regions of the Czech Republic (Olomouc, Ostrava, and Hradec Králové). The study used a prospective longitudinal design, covering three stages of measurement, in which the respondents completed the questionnaire set separately or as a structured interview with the researcher once they had been enrolled in the study, and then after 12 and 24 months.

Questionnaire battery

The questionnaire battery included a set of Czech versions tools for assessing quality of life – Quality of Life–Alzheimer's Disease (QOL-AD); depression – Geriatric Depression Scale (GDS); dignity – Patient Dignity Inventory (PDI-CZ); attitude to ageing – Attitude to Ageing questionnaire (AAQ); fear of falling – Falls Efficacy Scale - International (FES-I); physical fitness – Short Physical Performance Battery (SPPB); self-sufficiency in ADL – Bristol Activities of Daily Living Scale (BADLS-CZ); pain – Horizontal Visual Analogue Scale (HVAS). In addition, sociodemographic and clinical characteristics were recorded in all respondents: age, gender, education, social situation, frequency of social contacts, and basic hearing and vision examinations.

Instruments

Quality of Life–Alzheimer's Disease (QOL-AD) focuses on the assessment of the patient's current quality of life. It includes 13 items with 4-point Likert scale. The overall QOL-AD score ranges from 13 to 52 points, with a higher score indicating a higher quality of life [20,21].

The Geriatric Depression Scale (GDS) is a valid and reliable tool for depression screening that can be used even in individuals with mild to moderate dementia [22]. It contains 15 self-assessment items and the total GDS score ranges from 0 to 15 points.

The Patient Dignity Inventory (PDI-CZ) contains 25 items with a five-point Likert scale to identify problems that may cause concern about dignity in an individual [23,24]. The total PDI-CZ score ranges from 25 to 125 points. The suitability of PDI-CZ for use in older adults with dementia has been confirmed [25].

The Bristol Activities of Daily Living Scale (BADLS-CZ) contains basic and instrumental ADL, from completely independent to completely dependent. The questionnaire is completed by a person close to the patient who evaluates the performance of twenty activities in the patient's life. The overall score for BADLS-CZ ranges from 0 (completely independent) to 60 points (completely dependent) [26].

The Short Physical Performance Battery (SPPB) contains three functional tests that evaluate balance, walking speed over a distance of four metres, and repeated getting up from a chair. The overall score is 0 to 12 points [27]. The tool is also valid for older adults with dementia [28].

The Attitude to Ageing questionnaire (AAQ) evaluates subjective perceptions of ageing. It contains 24 items divided into three domains. The overall AAQ score is between 24 and 120 points. A higher score points to a more positive attitude towards ageing and old age [29]. It has been confirmed that even older adults with dementia are able to validly answer questions about their attitudes towards ageing [30].

The Falls Efficacy Scale - International (FES-I) has 16 items providing information on the degree of fear of falling for a number of activities of everyday life [31]. The overall score ranges from 16-64, with a higher score indicating greater fear of falling. The research used the Czech version of FES-I [32], which is also valid for older adults with dementia [33].

The Horizontal Visual Analogue Scale (HVAS) consists of a 10-cm line on which the patient records the level of subjectively perceived pain (no pain to extreme pain). HVAS can be successfully used for most patients with mild to moderate dementia [34].

Statistical analysis

The sample size calculation was based on an expected 0.5-point difference in QOL-AD tests over 24 months between the patients diagnosed with dementia and without it, a = 0.05 (two-tailed) and b = 0.8. Assuming that 30% of the participants would not complete the study, at least 290 respondents had to be addressed for each group.

The file was described using absolute and relative frequencies (mean, standard deviation [SD], and median). A comparison of the patient groups in quantitative analysis was carried out by a t-test for independent samples. A comparison of the quantitative variables of the first and third measurements was carried out using a paired t-test. Regarding qualitative variables, the groups were compared using the chi-square test. All tests were performed at a statistical significance level of 0.05. Stepwise was used to find significant predictors of the quality of life. Variables were included in the model as independent predictors: age, gender, education, social conditions (living alone – no), social activities (social events, visits, telephone contact, time spent alone), hearing and vision impairment, cognitive impairment, pain, physical fitness, self-sufficiency in ADL, depression, fear of falling, attitudes to ageing, and dignity. Normality was verified by the Shapiro-Wilk test. The independence of the residues was verified by the Durbin-Watson test, where values close to 2 indicate the absence of autocorrelation. Multi-collinearity was verified using the VIF (variance inflation) factor, where VIF > 10 indicates the possibility of multi-collinearity between dependent variables. The data in our study met the assumptions of multivariable linear regression. The quality of the model was evaluated by the coefficient of determination R² and adjusted R². The statistical software IBM SPSS Statistics for Windows, Version 23.0 (IBM Corp., Armonk, NY, USA), was used for statistical processing.

Results

In the first phase, 623 respondents were involved in the research, including 294 patients diagnosed with dementia at an early stage (109 [37.1%] males; mean age 79.6 ± 7.5 years; MMSE 22.7 ± 1.7) and 329 patients without dementia (99 [30.1%] males; mean age of 72.7 ± 7.0 years; MMSE = 29.2 ± 1.3). Their demographic data is presented in Table 1. The patients with dementia were significantly older (p < 0.001), had a lower level of education (p = 0.004), took part in social activities less often (p = 0.036), had a lower frequency of telephone contact with friends and family members (p = 0.002), spent more time alone (p < 0.001), and had hearing (p = 0.026) and vision disorders (p < 0.001).

The patients with and without dementia differed significantly across all the scales that were examined – Table 2. By comparing the results of the first (input) and control measurements after 24 months, it was found that among the patients with or without dementia, the levels of cognition, physical fitness, and degree of self-sufficiency (for all p < 0.0001) had deteriorated significantly and the fear of falling (p = 0.0002 among the patients with dementia and p < 0.0001 among the patients without dementia) had increased. The patients with dementia also experienced a deterioration in their quality of life (p < 0.0001) and pain assessment (p = 0.022). The patients without dementia had experienced a significant deterioration in their attitudes towards ageing (p = 0.0001) and assessment of dignity (p = 0.006) – Table 3.

Identification of the factors that affect the quality of life was carried out in the first measurement. Among the patients with dementia, dignity has been shown to be one of the factors influencing quality of life. Those who rated their dignity more positively (p < 0.0001) had a higher degree of self-sufficiency (p < 0.0001), a more positive attitude towards ageing (p = 0.011), and a lower level of depression (p < 0.0001). The patients without dementia had a better quality of life associated with lower levels of depression (p < 0.0001), less fear of falling (p = 0.0002), lower pain intensity (p = 0.009), female sex (p = 0.004), more frequent participation in social events (p = 0.004), and higher frequency of telephone contacts (p = 0.019) – Table 4.

The quality of life at the control examination 24 months after inclusion in the study only worsened among the patients with dementia. Therefore, factors that may have caused this difference were sought. The difference between the QOL-AD score values in the first and third measurements represented a dependent variable in the multidimensional linear regression model. The effect on the size of the change in the quality of life (the difference between the first and third measurements) among the patients with dementia had gender (a greater deterioration in the quality of life of the men [average = 2.8] than of the women [average = 1.8]; p = 0.021). Furthermore, it was the time spent alone daily (in those respondents who spent less than eight hours alone, there was a greater deterioration in quality of life [average values = 2.6 vs. 1.1]; p = 0.001). Social situations were also important predictors (those respondents who lived alone experienced a greater deterioration in their quality of life [average values = 3.2 vs. 1.7]; p = 0.0005) and frequency of visits (those respondents who had a lower frequency of visits experienced a greater deterioration in their quality of life [average values = 3.5 vs. 1.9]; p = 0.039). Other predictors were the overall scores of the first QOL-AD and BADLS-CZ measurements. Those patients with dementia who had a higher quality of life (a higher QOL-AD score) experienced a greater change in 24 months (greater deterioration in the quality of life; p < 0.0001). On the contrary, higher self-sufficiency (BADLS-CZ) at the input measurement correlated with a minor change in the quality of life (p = 0.011) – Table 5.

Discussion

The study presented demonstrated that the quality of life only worsened among the patients with dementia over the course of two years, while there was no change in the quality of life among the patients without dementia. The factors affecting the quality of life of the respondents were related to depression, dignity, attitude to ageing, fear of falling, pain, self-sufficiency in the ADL, and social involvement.

The initial evaluation (the first phase of research) showed that dignity is among the factors influencing the quality of life. Furthermore, it was confirmed that depression was the only factor with a persuasive factor affecting the quality of life among the patients with and without dementia. This corresponds to earlier findings that the severity of depression has a negative effect on the quality of life [18]. Early diagnosis and treatment of depression is therefore a key clinical priority for improving the quality of life among older adults. Dignity and attitudes towards ageing only affected the quality of life among the patients with dementia. Dignity as a multidimensional construct includes perception, knowledge, and emotion related to a sense of both self-worth and self-esteem, as well as to the respect and respect expressed by individuals. Patients in the early stages of dementia are aware of the deterioration of their cognitive abilities, often perceived as a stigma that reduces their self-esteem [15] and related personal dignity, which is negatively reflected in their assessment of their quality of life. Evidence that dignity is an important factor influencing the quality of life of older adults with dementia living at home has not yet been reported in other studies. In the early stages of dementia, a negative attitude towards ageing tends to be associated with the awareness of a gradual decline in cognitive abilities [35], which in turn significantly worsens the quality of life. Among the patients with dementia, the degree of self-sufficiency in the ADL was further affected by the rate of self-sufficiency, as with other authors [36-37]. The relationship between the intensity of pain and the quality of life was confirmed only among the patients without dementia. This may be related to the lowered ability of dementia patients to assess pain, which is often affected by impaired communication or short-term memory problems [38]. Social engagement (frequency of participation in social activities and telephone contact with relatives and friends) affected the quality of life only among the patients without dementia. This corresponds to the results of an earlier study, which stated that a low frequency of social relations is associated with a decrease in the quality of life of older adults [39].

After 24 months, the quality of life significantly deteriorated only among the patients with dementia. The predictors of this change were being male, the level of self-sufficiency in the ADL, and the degree of social engagement (variables: living alone, time spent alone during the day, and the frequency of visits). Social relations and social activities form a major source of personal subjective well-being, which includes both a positive assessment of the current situation and a balance of positive and negative emotions among patients with dementia [39]. Verloo et al. also state that more frequent visits by friends and family members have a positive impact on the quality of life of dementia patients [40]. Unlike our study, Ydstebø et al. [36] confirmed only a small reduction in the quality of life after 18 months among patients with dementia. The difference can be explained by the greater heterogeneity of their research population in relation to age and cognitive and functional limitations than was the case in our study. Because of the highly subjective nature of the quality of life, it is also possible that the generally positive or negative perception of life of some individuals had a stronger effect on the assessment of the quality of life than dementia.

Several limitations of our study should also be mentioned. First, patients with dementia were enrolled without distinguishing between different types of dementia, for which there could be different factors influencing their quality of life. Second, the group of respondents consisted only of older adults living in a domestic environment; therefore the results cannot be generalized to the entire older adult population. Third, other factors that could also have had an impact on the assessment of the quality of life, such as treatment for depressive manifestations, the economic security of the older adults, or comorbidity, were not monitored in the research.

Conclusion

The results of our study showed that depression was a common factor that influenced the quality of life among the patients with or without dementia in the initial assessment (the first phase of the project). Among the patients with dementia, a higher quality of life was further associated with a more positive assessment of dignity. It has been confirmed that dignity is one of the factors influencing the quality of life. Other factors that affected the quality of life of the older adults with dementia were their attitudes towards ageing and a higher degree of self-sufficiency. The patients without dementia had a better quality of life associated with less fear of falling, lower pain intensity, being female, more frequent participation in social events, and higher frequency of phone contacts.

The magnitude of the change in the quality of life after 24 months in older adults with dementia was affected by being male, the time spent alone daily, life without a partner (living alone), the frequency of visits, and the level of the quality of life and self-sufficiency at the first measurement. The results thus confirm the crucial importance of social relations and social engagement in maintaining the quality of life in the longer term in the early stages of dementia in older adults. Our findings can be useful in planning community strategies for older adults with dementia, both nationally and internationally.

Ethical principles

The study was conducted in accordance with the Helsinki Declaration of 1975 (and its revisions from 2004 and 2008). The study was approved by the Ethics Committee of the Faculty of Health Sciences of Palacký University Olomouc (UPOL-85361/1040-2015). All the respondents signed an informed consent to participation in the study. The study was registered prior to the inclusion of the first patient at: www.clinicaltrials.gov (Identified: NCT02845830).

Grant support

Supported from the programme project of the Ministry of Health of the Czech Republic with reg. No. 16-28628A. All rights under intellectual property protection regulations are reserved.

Conflict of interest

None of the authors declares a conflict of interest.

doc. PhDr. Helena Kisvetrová, Ph.D.

Centrum vědy a výzkumu

Fakulta zdravotnických věd UP v Olomouci

Hněvotínská 3

775 15 Olomouc

e-mail: helena.kisvetrova@upol.cz

Přijato k recenzi: 18. 12. 2019

Přijato do tisku: 2. 4. 2020

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