Abstract
Background/Aim: To investigate the effects of an exercise training program on physical and cognitive function in older patients with dementia. Patients and Methods: Thirty-eight patients with early-middle dementia (31 females and seven males), aged 80.6±6.9 years, residents in an Elderly Care Unit, either completed a 36-week structured exercise program (Intervention Group, IG; n=19), or received the usual medical care (Control Group, CG; n=19). Before and after the 36-week intervention, cognitive function was evaluated in both groups by Mini-Mental State Examination (MMSE) and depression by Geriatric Depression Scale (GDS); physical function was assessed using handgrip test, Timed Up to Go (TUG), Berg Balance Scale (BBS) and Chair-Stand Test (CST), and daily living functionality by Functional Rating Scale for Symptoms of Dementia (FRSSD). Results: As a result of exercise intervention, participants scored better in all functional and cognitive test assessments compared to the control group, as reflected by absolute and relative (%) differences in all metrics after the 36-week exercise program (p<0.001). Conclusion: A 36-week supervised exercise training program was found to result in significant improvements in physical and cognitive function of elderly patients in early to middle stages of dementia at an Elderly Care Unit. The promising results of this study shed more light on the adaptability of elderly patients with early and mild dementia to long-term exercise training and verified the feasibility of applying such programs in this clinical population.
- Cognitive impairment
- dementia
- exercise training
- elderly patients
- functional capacity
- physical activity
- prevention
As the population ages, health and social care services will come under pressure to serve elderly people with a wide range of chronic diseases that are accompanied by physical and cognitive impairment, including older adults with dementia. Dementia is a syndrome, commonly of a chronic or progressive nature, that leads to deterioration in cognitive function (i.e., the ability to process thought) beyond what might be expected due to the usual consequences of biological aging. It affects memory, thinking, orientation, comprehension, calculation, learning capacity, language, and judgment, whereas consciousness is not affected (1). The impairment in cognitive function is commonly accompanied by and occasionally precedes the changes in mood, emotional control, behavior, or motivation (2, 3).
Although age is the strongest known risk factor for dementia, it is not an inevitable consequence of aging. Further, dementia does not affect exclusively older people as young-onset dementia (defined as the onset of symptoms before the age of 65 years) accounts for up to 9% of cases (4, 5). Worldwide, around 55 million people have dementia, with over 60% of them living in low- and middle-income countries. As the proportion of older people in the population is increasing in almost every country, the number of people with dementia is expected to rise to 78 million in 2030 and 139 million in 2050 (1). Dementia is currently the seventh leading cause of death among all diseases and one of the major causes of disability and dependency among older people worldwide (6). Furthermore, these patients need the care of 2-3 people from their family environment and, thus, dementia has physical, psychological, social, and economic impacts on the patient’s family, and society in general (1). In Greece, according to epidemiological data 160,000 people suffer from dementia, and 280,000 from mild cognitive, which is considered a precursor of dementia.
Physical exercise is effective in improving the physical functioning of Elderly Care Unit (ECU) residents with dementia. Additionally, exercise training programs can help mitigate or delay the decline in activities of daily living of patients with mild to moderate dementia (7, 8). Specifically, in most daily activities, balance along with lower limb muscle weakness have been identified as independent risk factors for falls in patients with dementia, while the fear of falling is also a risk factor for inactivity, thus creating a vicious circle for these patients (9). Fear of falling is also responsible for the inability to perform functional tasks, such as walking, sitting-to-stand transfer, walking speed, climbing steps, and lower body dressing (10). Improving balance and muscle function, apart from reducing fall incidence, may increase mobility in people with dementia via improving their confidence. Thus, exercise training programs may contribute to the prevention of functional decline and the improvement of balance in the elderly with dementia, while physical exercise has also been found to be beneficial for the cognitive function of these patients (11, 12).
Therefore, the aim of this study was to investigate the efficacy of a structured exercise training program on the physical and cognitive function in ECU patients with early- to middle-stage dementia, hypothesizing that this long-term intervention would positively affect both their cognitive functioning and functional capacity for activities of daily living.
Patients and Methods
Patients. The inclusion criteria for participating in the study were: (i) Diagnosis of dementia (early- to middle-stage), (ii) age 75 to 85 years, (iii) ability to hear and understand spoken Greek sufficiently, (iv) a score on the Mini-Mental State Examination (MMSE) of between 10 and 24 (13), (v) stable medical condition for at least 6 months, and (vi) ability to complete the 6-minute walking test (6MWT). The exclusion criteria were the patient being medically unstable, psychotic, or having communication problems. All residents were screened by an adaptive physical activity educator and a neurologist using the Functional Rating Scale for Symptoms of Dementia (FRSSD) (14) and MMSE a week before the initiation of the exercise training intervention. Out of a total of 57 nursing home residents, 38 met the inclusion criteria (Figure 1). Specifically, 31 female and seven male elderly patients with early- to middle-stage dementia volunteered to participate in the study and were randomly assigned to either the exercise training intervention (IG) or the control (CG) group on a 1:1 basis (Table I). The study was approved by the National and Kapodistrian University of Athens Medical School (111/15-04-2019) in collaboration with the Elderly Care Unit and written informed consent was given either by the patients or their legal guardians, while all experimental procedures conformed to the Declaration of Helsinki.
Flowchart of the participant selection process.
Somatometric, demographic and clinical characteristics of the study participants at baseline.
Experimental design. This study was a 36-week randomized, controlled, single-blind study of elderly individuals with early- to middle-stage dementia living in an ECU. After assessing the level of frailty, physical performance and cognition, informed consent was taken (15), and participants were randomized using a 1:1 ratio to the IG or the CG (Table I). A physical therapist, not involved in the intervention and not being among the staff of the ECU, and an exercise scientist then assessed the physical performance, while a neurologist evaluated cognition, behavior, and depression. The personnel of the institution were also blinded to the group allocation of the participants. After completion of the exercise program, both groups were re-evaluated.
Exercise training program. Patients in the IG were instructed to exercise 3 days per week (2 days in the morning before lunch and 1 day in the afternoon) for 50 minutes per session, for 36 consecutive weeks under the supervision of an exercise scientist. Each session included a 10-minute standardized warm-up, 12 strengthening exercises for upper and lower limbs and the body, as well as four exercises for improving balance. The initial training volume was low; during the first 4 weeks, one set of eight repetitions per exercise was carried out; this was progressively increased to three sets of 12 repetitions during the last 4 weeks of the training program. Strength training for upper extremities included lifting light weights, range-of-motion exercises, and biceps strengthening exercises, whilst lower extremity exercises included leg extension and squatting in the form of repeated chair stand-ups. Balance and co-ordination training included exercises using hoops, balls and lines on the ground, as well as one-leg balancing exercises.
In the present study members of the intervention group participated at the exercise as a group. Group exercise programs are considered most effective for patients with early- or mid-stage dementia and several studies have shown that group exercise is feasible for these patients (4, 7, 8, 16). Thus, the exercise training program utilized in this study was not individualized, although each participant was encouraged to exercise according to his/her physical capacity. Although there were inter-individual differences regarding physical capacity, no significant variation was observed during the sessions, which were accompanied by music. Reasons for missing a session were behavioral, cognitive, or physical inability to perform the exercises, or medical reasons, such as influenza, illness, or pneumonia.
Control group. Participants in the CG received routine medical care and had light recreational activities, such as playing games, painting, watching TV, listening to music, and having conversations without participating in any form of exercise. All participants were assessed at baseline and after the completion of the 36-week exercise training program.
Physical function assessment. Muscle strength was evaluated by a handgrip strength test using a handheld dynamometer (Deyard EH101, electronic hand dynamometer 90 kg/200 lbs; Shen Zhen Shi Yong Hua E-Commerce Co., Ltd, Shenzhen, PR China) and measurements were performed on both hands. The participants were instructed to grip the dynamometer as strongly as they could, and verbal motivation was given by the assessor. The testing protocol consisted of three maximal isometric contractions (3 seconds each) for each hand with a 1-minute rest between trials and the maximum value was recorded. The handgrip strength test has excellent reliability when used in the elderly with h mild cognitive impairment, or early- or middle-stage dementia (17).
Physical capacity and static-dynamic balance were evaluated using the Time Up to Go test (TUG), which has excellent reliability in older adults (18). The participants were asked to rise from a chair with armrests (seat 43 cm high), walk 3 meters with or without aid, turn, and return to the chair, at a regular pace. Time recording began once the participants shifted their weight forward to stand up and ended when the participants returned and sat in the chair. The participants were allowed to use the armrests during the sit–stand and stand–sit movements.
Balance ability was evaluated using a 14-item Berg Balance Scale (BBS), which involves different tasks, such as functional balance control, transfer, turning and stepping. Each is scored on a five-point ordinal scale, ranging from 0-4, with 0 indicating the lowest level of function, and 4 the highest, resulting in a maximum total score of 56. The test has excellent reliability for older adults in a clinical setting (19-21).
Lower limb strength and endurance were evaluated using the Chair-Stand Test (CST). The participants were instructed to rise from and sit on a chair (seat 43 cm high) without armrests, with their hands on the opposite shoulder, crossed at the wrists. The number of times they rise from the chair in 30 seconds is the score. The reliability of the test has been evaluated in older adult nursing home residents (20, 22).
Exercise capacity was evaluated using the 6MWT, which was performed according to the instructions of the American Thoracic Society (22). Specifically, the participants were instructed to walk in a 15-meter corridor from end to end, at their own pace, with or without assistance, while attempting to cover as much distance as possible in the allotted 6-minute time. The maximum distance walked in 6 minutes was assessed. The test has been found to have excellent reliability in nursing home residents with dementia (23, 24).
Daily living functionality and cognitive function assessment. The FRSSD (14) was used to assess the functioning of each patient in 14 activities of daily living: Eating, dressing, incontinence, speech, sleeping, face recognition, personal hygiene, and memory for names, episodic memory, vigilance, global confusion, orientation (place), emotion, and social behavior. The rating scale ranges from 0 to 3 points (0: independence in activities without help, 3: dependence with complete help). FRSSD is extremely reliable for use in the elderly with mild cognitive impairment and early or middle dementia (25).
Cognitive performance was evaluated using the MMSE (13), which is a 11-item questionnaire that examines five areas of cognitive function, i.e., orientation in time and place, memory, attention, naming, comprehension, execution of oral and written instructions, and written language. The maximum score in this questionnaire is 30. A score below 24 was found to be indicative of patients with possible dementia, though scoring in MMSE has been shown to be affected by education, race, and socio-economic level of the scorer (26).
Depression was evaluated using Geriatric Depression Scale. This scale consists of 15 yes/no questions and each question is scored either as 0 or 1 point. Of the 15 items, 10 indicate the presence of depression when answered positively, while the rest indicate depression when answered negatively. Scores of 0-4 are considered normal, depending on age, education, and complaints; 5-8 indicate mild depression; 9-11 indicate moderate depression; and 12-15 indicate severe depression (26). All the above scales/questionnaires have been adapted to and validated for the Greek population (26, 27).
Data analysis. Data were analyzed with SPSS Statistics v.25.0 software (IBM Corporation, Armonk, NY, USA). The normality of data was evaluated using the Shapiro-Wilks test. The TUG and MMSE data were found to be normally distributed as were the absolute and relative (%) differences between pre and post intervention values for the CST. Therefore, two-way analysis of variance for independent samples with repeated measures on one factor (time) with Greenhouse-Geisser corrections was used to investigate differences between groups after 36 weeks of exercise training for TUG and MMSE. Absolute and relative (%) differences between the two groups after intervention were evaluated with independent Student’s t-test for the CST and MMSE, whereas for the rest of the evaluations, Mann-Whitney test was applied. Associations between variables were analyzed by Pearson correlation coefficient (r). Data are expressed as the means±standard deviation in tables and as means±standard error in figures. Statistical significance was set at p<0.05.
Results
There were no significant differences in somatometric and demographic characteristics between the groups at the start of the exercise intervention program (Table I). Participants in the IG completed 117 exercise sessions during a period of 36 weeks and all of them completed the study (100% attending rate).
All functional and cognitive data before and after intervention for the two groups are presented in Table II and Table III, respectively. The relative differences after intervention in each group and their comparisons, with the corresponding significance for each functional and cognitive assessment have also been incorporated in Figure 2 and Figure 3, respectively.
Baseline (pre) and post-intervention values for all functional parameters (mean±standard deviation), and their difference.
Baseline (pre) and post-intervention values for all cognitive parameters, and their difference (mean±standard deviation).
The relative difference (%) for all functional parameters. *Significantly different from CG at p<0.001. BBS: Berg Balance Scale; CG: control group; CST: 30-second chair-stand test; HG: hand grip; IG: intervention group; 6MWT: 6-minute walk test; TUG: Timed Up to Go.
The relative difference (%) for all cognitive parameters. *Significantly different from the control group (CG) at p<0.001. CG: Control Group; MMSE: Mini-Mental State Exam; FRSSD: Functional Rating Scale for Symptoms of Dementia; GDS: Geriatric Depression Scale; IG: intervention group.
Physical function. Muscle strength: At baseline, maximal isometric handgrip strength was similar in both groups, while no significant changes were found following the intervention in either group compared to baseline values (p>0.05) (Table II). However, the absolute differences were higher in IG (Table II), and the relative differences were also higher in IG, indicating an improvement at the end of the program compared to CG participants, who demonstrated an average decrease of 11.8±10% compared to baseline (Figure 2).
Functional mobility: At baseline, TUG scores, reflecting mobility, static-dynamic balance, and locomotion performance, did not differ between the two groups (p=0.38). Following the 36-week intervention period, there was a significant improvement in TUG values in the IG group, whereas a deterioration of the TUG score was observed in CG (Table II). Consequently, absolute (Table II) and relative differences were lower in IG, whereas in CG, an increase was observed (Figure 2).
Regarding the CST scores, after the completion of the intervention period, there was a significant improvement in CST values in the IG group as a result of the exercise program, with a deterioration in CG as indicated by the absolute (Table II) and relative differences (Figure 2).
Balance: As a result of the 36-week intervention period, there was a significant improvement in BBS score in the IG and a deterioration in the CG [Table II and Figure 2].
Exercise capacity. Following the completion of the exercise training program, the 6-minute walking distance was improved in IG whereas it decreased in CG, resulting in a significant difference between groups (Table II and Figure 2).
Interestingly, the handgrip strength was positively correlated with balance (r=0.95, p<0.005), 6MWT (r=0.72, p<0.001), and TUG physical performance (r=0.45, p<0.05).
Daily living functionality and cognitive function. This baseline MMSE score was different between groups (p=0.033). However, CG experienced a decline after the 36-week exercise intervention program (p<0.001), whereas in IG, the MMSE score was maintained (Table III). Consequently, absolute (Table III) and relative differences (Figure 3) were also different in favor of the IG.
A similar response was observed in the Geriatric Depression Scale scores, where patients in the IG exhibited a decrease in their depression as a result of exercise, while participants in the CG demonstrated an increase in depression (Table III and Figure 3).
Moreover, for the FRSSD score, absolute (Table III) and relative differences (Figure 3) between groups were also different in favor of IG, as after the 36-week exercise program, the response for patients in CG increased whereas that for those in IG decreased. Interestingly, the MMSE score was positively correlated with depression (r=0.66, p<0.001) and FRSSD (r=0.64, p<0.001).
Discussion
This study investigated the effects of a long-term exercise training program on patients characterized by early to middle stages of dementia and lived at an ECU. The main finding of our study was that regular group exercise results in beneficial effects on functional mobility, improving muscle strength, distance covered in the 6MWT and balance, as well as on daily functionality, improving the FRSSD scale and reducing the rates of depression in older patients with early- to middle-stage dementia. Our findings are consistent with previous studies that investigated the effect of group exercise on ECU residents (11, 28, 29). More specifically, it has been demonstrated that patients with Alzheimer’s disease living in an ECU exhibited significant improvements in functional mobility and the distance covered during the 6MWT after a training program that consisted of 30 minutes of self-paced assisted walking three times a week for 16 weeks (30, 31).
Physical activity has been suggested to improve cognitive and mental function, reducing the risk of age-related cognitive impairment in health and disease (32). Specifically, physical activity interventions of moderate to vigorous intensity might induce a sequence of biochemical, physiological, and structural changes in the brain. Indeed, the improvement of cerebral blood flow, neurotrophic factor release, neurogenesis, immune system efficacy, and metabolism, acting synergistically against inflammatory processes and the atrophy of brain structures, which might lead to a minimization of cognitive impairment and dementia (5, 33). Furthermore, motor coordination and balance activities included in exercise training programs have been found to influence cognition, executive function, and balance positively, potentially through the activation of specific cortical connections (34). Moreover, the clinical significance of these functional mobility- and balance-improving activities is high considering that prevention of falls is of great importance in elderly people suffering from dementia, as they are at high risk of falling and are characterized by poor outcomes and particularly high mortality rates (35). A meta-analysis that included seven related randomized controlled trials demonstrated that exercise effectively reduced the risk of falls in elderly patients with cognitive impairment (36). Moreover, good performance in the TUG test (37) and BBS (38) have been negatively correlated with the risk of falls. Overall, considering these reports, the significant improvements in BBS and TUG revealed in our study highlight the clinical importance of a regular exercise training program for patients suffering from dementia.
Moreover, patients with dementia have been demonstrated to suffer from a progressive loss of global cognitive function. Previous studies have reported an average 12-month cognitive decline of 2.3 MMSE points in individuals with dementia diseases (11, 28, 39). In our study, global cognitive function of patients in the exercise training group improved by 2 MMSE points following the 36-week physical exercise intervention, without this improvement being significant compared with the control group. Our findings are in line with previous studies (4, 40), suggesting that a 36-week exercise training intervention does not appear to be adequate to induce significant neural adaptations in patients with early- to middle-stage dementia.
Furthermore, maximal isometric handgrip strength has been widely used to evaluate physical function and frailty in older adults (16). In our study, no significant improvement in handgrip strength was found in IG following the exercise training program, even though improvements were observed in other physical function parameters, as indicated by the TUG and CST improved scores, suggesting that maximal handgrip strength may not be a definitive tool for measuring overall muscle strength and physical function in these patients (41).
In addition, this study revealed that in both groups, the mean distance covered in the 6MWT at baseline (321 m and 312.6 m for the IG and the CG group respectively) was almost half that expected (over 600 m) for healthy people of the same age, indicating that these patients had poorer exercise capacity compared with healthy age-matched people. However, the significant increase in the mean distance covered in the 6MWT by the patients in IG suggests that the exercise training intervention was sufficient to lead to improvements in cardiovascular and overall physical function in patients with early- to middle-stage of dementia, corroborating previous findings (23, 42, 43).
Our study has limitations, such as its relatively small sample size and the fact that it was conducted in elderly populations with a current diagnosis of early- to middle-stage of dementia living in an ECU. Thus, our findings might not be generalized to dementia patients with different characteristics, e.g., those having serious comorbidities or living with their own families.
In conclusion, a structured long-term exercise training intervention of moderate intensity was found to be beneficial for elderly patients with early to middle stages of dementia that live in ECU, improving their daily living functionality, physical function, functional mobility, and depression. These results highlight the feasibility and clinical importance of implementing such exercise programs in this clinical population and the adaptability of elderly patients with early and mild dementia to long-term exercise training. Moreover, these findings might be a valuable resource for further identifying the optimum characteristics of exercise training for patients with dementia and for developing strategies for the prevention and treatment of aging-associated cognitive and functional impairments.
Acknowledgements
The Authors are grateful to the study participants for their invaluable contribution to this research.
Footnotes
Authors’ Contributions
MB and AP contributed to the study conception and design. Material preparation, data collection and analysis were performed by MB, IP, KL and CC. Statistical analysis was performed by EC and CC. Supervision and validation were conducted by AP, MM, SP and MK. The first draft of the article was written by MB and all Authors edited the final version. All Authors read and approved the final article.
Conflicts of Interest
The Authors declare no conflicts of interest.
- Received July 15, 2023.
- Revision received September 15, 2023.
- Accepted September 22, 2023.
- Copyright © 2024 The Author(s). Published by the International Institute of Anticancer Research.
This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY-NC-ND) 4.0 international license (https://creativecommons.org/licenses/by-nc-nd/4.0).
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