Analysing the Effect of Cognitive Function and Activities of Daily Living on Quality of Life among the Elderly in Malang, Indonesia

Introduction

The elderly represent the final phase of the human life cycle marked by numerous physical and mental changes. Physical changes include gray hair, facial wrinkles, sensory impairments, and reduced immunity [1]. Mentally, older adults may experience personality changes, loss of motivation, and interest [2]. They also often experience social decline characterized by withdrawal from social activities. These changes can affect their health, making them more dependent, and if prolonged, can affect their quality of life (QoL) [3]. In 2023, the elderly population accounted for approximately 26.77% (54 million) in Indonesia; while in entire Southeast Asia, it accounted for about 38% of the population [4]. This number is expected to continue to grow rapidly until 2030 [5, 6].

In addition to the natural aging process, cognitive decline is a common problem among the elderly [7, 8]. Cognitive function is influenced by several factors, including language, reasoning, memory, and intelligence, all of which tend to decline with age [9]. Risk factors that often contribute to cognitive decline in older adults include age, family history, gender, depression, and comorbidities [10]. This decline is due to degeneration of the central nervous system, which can lead to forgetfulness. In some cases, it can progress from mild cognitive impairment to dementia [11]. Research shows that approximately 39% of people aged 50-59 years are forgetful, and in people over 80 years, the rate is over 85% [12, 13]. Although early forgetfulness may not initially interfere with daily functioning, it can develop into more serious conditions that affect psychosocial well-being and daily functioning [14].

While activities of daily living (ADL) assess an older adult’s ability to perform daily tasks such as bathing, toileting, dressing, and moving aound [15]. People who have difficulty performing these tasks may feel less satisfied with life, which may negatively impact their QoL [16]. Low QoL in the elderly is often due to various health problems that make it difficult for them to perform daily tasks [17]. Declining mental abilities, changing social roles, and conditions such as dementia and depression further complicate these problems [18, 19]. Thus, analyzing the factors that influence QoL is crucial to maintaining the health and well-being of older adults. Although studies have been conducted to analyze QoL among the elderly in Indonesia, none have examined the combined effects of cognitive function and ADL on QoL [20, 21]. Consequently, the objective of this study was to analyze the effects of cognitive function and ADL on QoL among the elderly in Malang, Indonesia.

Material and Methods

Study design

This study employed a cross-sectional study design. We recruited 83 elderly people who resided in a nursing home in Malang (Pondok Lansia Al-Islah, Rumah Sosial Gempol Sukun, Komunitas Lansia Joyogrand, and Rumah Sosial Belas Kasih) from April to September 2023. Participants were recruited using purposive sampling methods with the following inclusion criteria: (a) 60 years of age or older, (b) fully conscious and capable of communicating in Indonesian, and (c) willing to participate in this study. Individuals diagnosed with dementia were excluded from participation.

Participants

Table 1 presents the main sociodemographic characteristics and their differences based on QoL indicators. A total of 83 participants were included in this study. Almost 70% of them were aged 65 years or above, and 80.8% were male. Regarding BMI, 45.8% of the respondents were overweight, while 28.9% were obese. Most of the participants were married (54.2%), had secondary education (56.5%) and lived in urban areas (56.6%). Although there were no significant differences in QoL based on sociodemographic characteristics (p>0.05), higher QoL scores were observed among healthy weight participants and university educated participants: 67.32 pts and 68.21 pts, respectively.

Measurements

Short Portable Mental Status Questionnaire (SPMSQ). The Short-Term Portable Mental State Questionnaire (SPMSQ) was developed by E. Pfeiffer [22]. The Indonesian version of the SPMSQ [23] was used to assess the cognitive functions of the participants in this study. The questionnaire consists of 10 questions (Suppl. 1), with incorrect answers scored as 0 pts and correct answers as 1 pt. The score ranges from 0 to 10 pts, with higher scores indicating higher cognitive function. The questionnaire covers various cognitive aspects, including orientation to the environment, attention to current events, thinking skills, short-term and long-term memory, sequential arithmetic skills, and general knowledge. According to previous studies, the Cronbach’s alpha for this instrument is 0.82 [22].

The Barthel Index. The Barthel Index was used to assess ADL [24]. This measurement instrument includes 10 sub-items, including feeding, moving around, personal hygiene, getting on/off the toilet, bathing, walking on flat surfaces, climbing stairs, dressing, and controlling bowel and bladder function. The maximum possible score on this scale was 100, with a higher score indicating higher functional independence. According to previous studies, the Cronbach’s alpha for participants with mild to moderate cognitive impairment for this instrument is 0.91 [25].

Short Form 36. The Short Form 36 (SF-36) questionnaire was employed to assess the QoL in respondents [26]. This instrument allows assessing the physical, mental and social health status of the elderly. The SF-36 questionnaire has previously shown its suitability for clinical research and practice in various populations [27]. This questionnaire includes 36 items that assess 8 domains, viz.: general health, physical functioning, role limitations and physical health status, body pain, energy and vitality, emotional health, and general health. Scores for each domain were converted to scores from 0 to 100, where a higher score corresponds to a higher level of QoL. This instrument demonstrates good validity and reliability in assessing the eldrly in the community context [28].

Sociodemographic characteristics

Participants were also asked to provide sociodemographic data using a self-administered questionnaire. The questionnaire included information on their age (60-64/65-69/70+); gender (male/female); body mass index (BMI) (underweight, healthy weight, overweight, obese); marital status (single/married); educational level (no primary school diploma, primary school, middle school, high school, university) and place of residence (urban/rural).

Statistical analyses

Descriptive univariate statistics included frequency and percentage for categorical variables. For quantitative variables (QoL, cognitive function, and ADL), normality was tested using the Kolmogorov-Smirnov test, which showed that all variables were normally distributed (p>0.05). Then, depending on the type of variable, independent t-test, analysis of variance (ANOVA), or Pearson correlation coefficient were used to evaluate the association between two variables. Multivariate linear regression analysis was performed to examine the relationship between predictors and QoL. The level of statistical significance was set at p<0.05, and all analyses were performed using SPSS version 20 (SPSS, Chicago, IL, USA).

Ethical considerations

Ethical approval for this study was obtained from the Ethics Committee of University of Muhammadiyah Malang, Indonesia (No. E.5.a/231/KEPKUMM/VIII/2023). In addition, all participants signed an informed consent form before data collection.

Results

Table 2 presents the results of the Pearson correlation analysis, which examined the relationship between cognitive function, ADL, and QoL. The results showed that both cognitive function and ADL directly and significantly correlated with QoL (p<0.05), with correlation coefficients of 0.24 and 0.18, respectively. However, no significant correlation was revealed between cognitive function and ADL.

Table 3 presents the results of the multiple linear regression analysis, which examined the predictors of QoL in older adults. After accounting for other variables, cognitive function and ADL were found to be the most significant factors of QoL in the elderly (p<0.05). Higher cognitive function and higher ADL scores were positively associated with higher QoL, with β values of 0.12 and 0.29, respectively. The adjusted R² of this regression model was 0.18.

Discussion

Among the 83 participants recruited in this study, it was found that better cognitive function and higher ADL scores significantly contributed to better QoL among the elderly. This finding is consistent with previous studies [29, 30], which reported that cognitive function plays a critical role in determining QoL as it includes perception, reasoning, problem solving and memory. With age, these cognitive capabilities gradually decline, which can significantly affect the ability to perform daily activities [29-31]. In severe cases, old-age-related mental illnesses can develop [8]. If this condition persists, it can negatively affect QoL. Previous studies [32, 33] also reported that cognitive decline corresponds to a reduction in physical function and health-related quality of life. In addition, their study also found an increase in depression and a decrease in QoL associated with lower cognitive levels among the elderly. Cognitive impairment has been found to have a significant impact on QoL, with studies showing that cognitive decline can reduce QoL by approximately 7% in the elderly [29, 30, 34].

ADL were also directly associated with QoL. A previous study found that independent older adults living in urban areas had twice the QoL as the elderly with disabilities in the same setting [20]. Furthermore, studies have shown that older adults with good ADL functioning were strongly associated with higher QoL. In contrast, lower ADL capacity was strongly associated with depression and lower QoL in three different countries [13,35]. Older adults who have difficulty with ADL due to age, illness, or disability may experience reduced QoL as a result of loss of independence [16, 36]. Therefore, maintaining ADL can contribute to improving QoL [37, 38] as it allows older adults to engage in leisure and social activities that enhance their sense of satisfaction and self-fulfillment. Therefore, improving ADL and cognitive function in older adults should be a primary goal in health and rehabilitation programs aimed at improving QoL of community-dwelling older adults.

Although this study contributes to the understanding of the factors associated with QoL of the elderly in Malang, Indinesia, several limitations should be considered. First, due to the limited number of variables examined, other important factors associated with QoL, such as balance, gait, and functional activity, were not analyzed. Second, the cross-sectional nature of the study does not allow drawing causal inferences regarding the relationships between explanatory factors and QoL. However, despite these limitations, our study provides valuable evidence on the importance of considering cognitive function and ADL in both research and practice to improve QoL of older adults in Malang.

Conclusion

This study showed that cognitive function and ADL were positively associated with improved QoL. Therefore, it is necessary to develop an individualized intervention plan that includes regular assessment of physical function, cognitive function, and ability to perform ADL. In addition, early detection and intervention strategies should be implemented to improve the QoL of the elderly.

Acknowledgments

We would like to thank Pondok Lansia Al-Islah, Rumah Sosial Gempol Sukun, Komunitas Lansia Joyogrand, and Rumah Sosial Belas Kasih for their work and dedication, and all participants who kindly agreed to participate in this study.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional research committee and with the 1964 Declaration of Helsinki and its later amendments. This study was approved by the Institutional Review Board of the Ethics Committee of Muhammadiyah University Malang, Malang, Indonesia, under number E.5.a/231/KEPKUMM/VIII/2023.

Conflict of interest

All contributing authors declare no conflicts of interest regrading this study.