Journal 
Ⅰ. Background
Stroke is a serious, chronic, non-infectious disease with serious negative effects on health. Stroke is the leading cause of death and disability in adults, with high incidence; survival, mortality , and recurrence rates; and economic burden. The risk factors for stroke are categorized as indirect and direct factors. Indirect risk factors include age, race, and genetic factors, while direct risk factors include hypertension, diabetes, hyperlipidemia, heart disease, smoking, drinking, diet, overweight or obesity, sedentariness, and psychological factors(Roth et al., 2020). Cognition refers to the process of acquiring or applying knowledge and processing information such as perception, memory, thinking, imagination, and language. The factors associated with cognitive impairment included decreased local blood flow in the brain, blockage of nerve pathways, and abnormal neuronal metabolism after a stroke. The risk of cognitive impairment varies according to the site of the stroke. For instance, stroke in the frontal lobe caused by damages to the anterior cerebral artery(ACA) has the greatest effects on cognitive function. Strokes in the temporal lobe, parietal lobe, occipital lobe, and thalamus caused by damage to the middle cerebral artery(MCA) and posterior cerebral artery(PCA) are also related to impaired cognitive function(Rava et al., 2021).
Neuroplasticity comprises the theoretical basis of cognitive training. Cognitive training must consider motor dysfunction, cognitive function, anxiety, depression, and other psychological developmental characteristics of patients with stroke and their effects on attention, perception, memory, thinking, emotional ability, and cognitive flexibility(Carey et al., 2019.) Thus, specific goals must be set, and personalized training programs developed . The cognitive training methods that are currently commonly used in clinical practice include occupational therapy, computer-aided and virtual techniques, telecognitive rehabilitation, implicit memory methods, error-free learning methods(Brogan, Ciccone, & Godecke, 2021).
Many patients with stroke have functional impairments such as cognitive, sensory, language, motor, and swallowing disorders, emotional disorder, which affect their normal lives (Schöttke et al., 2020). Depression is a kind of emotional disorder. Patients with stroke face challenges in accepting the difficulties in performing the activities of daily living due to sudden physical dysfunction. These patients may also develop psychological reactions such as fear, rejection, depression, and irritability from concerns about their prognosis (Yang et al., 2019). The delayed recovery of body functions and serious burden of their disability on their family and life lead to despair, concern, depression, and anxiety in patients with stroke. Some patients also show a lack of positivity and become excessively dependent on others as they remain bedridden. Additionally, patients may lose confidence in treatment, do not actively participate in treatment, and may be dissatisfied with their family's interest and recommendations from the medical staff, eventually leading to treatment failure (Adamit, Shames, & Rand, 2023).
Sikora et al. (2004) reported that cognitive function is highly correlated with health-related quality of life. Park et al. (2010) showed that the current functional status in patients with chronic stroke was significantly related to the current health-related quality of life and that comorbidities, cognitive impairment, depression, age, and marital status affected the health-related quality of life. Previous studies mostly focused on the depression scale and factors related to the activities of daily living to assess the quality of life of patients with stroke; however, relatively few studies have evaluated the effects of cognitive training on cognitive function, daily life activities, depression, and anxiety in these patients.
Therefore, this study assessed the effects of cognitive training on cognitive function, depression, anxiety, and activities of daily living in patients with stroke. We aimed to provide basic data on various treatments to improve the activities of daily living and quality of life of patients with stroke.
Ⅱ. Methods
1. Study participants
This study included a total of 64 patients who were hospitalized at M medicine hospital in M city within 4 weeks of being diagnosed with stroke over 16 months, from January 2019 to April 2021. Patients who satisfied the selection criteria and who voluntarily agreed to participate after fully acknowledging the purpose and methods of the study were included. The selection criteria were as follows. First, patients diagnosed with stroke by computed tomography(CT) or magnetic resonance imaging(MRI). Second, patients with no visual or auditory deficits and no difficulties in communication. Third, patients with no brain herniation and no change in intracranial pressure. Fourth, patients without progressive neurological disorders(Table 1).
2. Measurement method
1) Cognitive function
The MMSE is the most commonly used tool worldwide to evaluate cognitive function. It is a proven tool used worldwide in epidemiology studies and clinical practice. The test time is as short as 10 minutes. The tool consisted of: 10 items (10 points) related to orientation in time and space, 3 items related to memory registration (3 points), attention and concentration according to calculation ability (5 points), memory recall (3 points), 5 items on language (8 points), and visuospatial function on drawing overlapping pentagons (1 point). As described previously, cut-offs of <15, 16-24, and 25-30 points were used to divide cognitive function into severe impairment, mild impairment, and normal function (Khaw et al., 2021).
2) HDRS
The HDRS comprised 17 items used to assess depression, including physical symptoms. Nine items related to depressed mood, feeling of guilt, suicide, work and activities, retardation, agitation, psychic anxiety, somatic anxiety, and hypochondriasis were scored from 0 to 4 points, while seven items related to insomnia(early), insomnia(middle), insomnia(late), somatic gastrointestinal symptoms, somatic general symptoms, genital symptoms, and insights were scored from 0 to 2 points. The item on loss of weight was scored from 0 to 2 points in the present study. The total score ranged between 0 and 52 points, with scores of 0-6, 7-17, 18-24, >24 points indicating normal status, mild depression, moderate depression, and severe depression, respectively (Obeid et al., 2018).
3) HAM-A
The HAM-A is a semi-structured interview tool comprising 14 items used to assess the severity of anxiety symptoms; these items are divided into factors related to symptoms of mental anxiety and physical symptoms. The interviewer evaluated the severity of each item on a 5-point scale (0-4 points) to calculate the total score, with scores of 0-7, 8-14, 15-23, and >24 points indicating normal, mild anxiety, moderate anxiety, and severe anxiety, respectively(Thompson, 2015).
4) Activities of daily living
The MBI was used to evaluate the independent function and activities of daily living of patients. It is used to comprehensively evaluate functional impairment based on independence in performing activities of daily living. The score reflects the level of assistance required for activities of daily living. The tool consisted of 10 items on daily activities: grooming, bathing, feeding, dressing, toilet use, stairs, bowels, bladder, mobility, and transfer. Each item was scored on a 5-point scale, with the total score ranging from 0 to 100 points. Scores of 0-24, 25-49, 50-74, 75-90, and 91-99 points indicated complete, severe, moderate, mild, and minimal dependence, respectively. The reported test-retest and interrater reliability were .89 and. 95, respectively(Lee et al., 2020;Yang et al., 2021).
3. Intervention method
This study was conducted from January 2019 to April 2021 and included those patients who were hospitalized for the treatment of stroke during this period and satisfied the selection criteria. All participants received conventional physical therapy provided by the institution, while the EG underwent the additional cognitive training program provided in this study.
1) Cognitive training program
The cognitive training program was based on the cognitive rehabilitation training method described by Jang, Lee, & Jung (2018). The program consisted of tracing and writing, dotted line drawing, connecting related things, counting numbers, and coloring. Tasks appropriate for the educational level of the individual participants were selected. Two occupational therapists with more than 5 years of clinical experience performed the training, the program was conducted twice weekly for 8 weeks. Each session lasted for 30 minutes and a total of 8 hours of cognitive training was provided(Table 2).
2) General physical therapy
All participants underwent general physical therapy(GPT). The GPT protocol was developed from traditional neuro-developmental treatment(NDT) based on motor control theory and motor learning. The GPT was conducted by physical therapists to assess the functional limitations of each patient and improve postural control, selective movement, and activities of daily living (Díaz-Arribas et al., 2020). The GPT protocol consisted of static stretching that applied external force for a certain time in a specific position, dynamic stretching performed by the participants for preventive purposes after training of patients and caregivers, functional electrical stimulation(FES) to the paralyzed motor unit that lost voluntary control to induce muscle contraction through electrical stimulation. GPT was provided five times weekly for 8 weeks. Each session lasted for 30 minutes and 1 hour long in the EG and CG, respectively.
4. Data Analysis
Data were analyzed using IBM SPSS Statistics for Windows, version 21.0. Shapiro-wilk was conducted to verify the general characteristics of the research subjects. Analysis of covariance(ANCOVA) was conducted to compare cognitive function, depression scale, anxiety scale, and activities of daily living between the two groups. Paired t-tests were used to verify statistical significance within the groups.
Ⅲ. Results
1. Comparison of variable in the between groups
The difference in cognitive function(p<.001), HDRS(p<.05), HAM-A(p<.05), MBI score(p<.05) between the groups was significant(Table 3).
2. Comparison of variable within the groups
The difference in cognitive function(p<.05), HDRS(p<.05), HAM-A(p<.05), MBI score(p<.05) whitin the EG was significant. but not significantly change in the CG(Table 4)
Ⅳ. Discussion
Stroke is a neurological deficit caused by injuries to blood vessels in the brain. Depending on the damaged area of brain tissue, various neurological disorders such as decreased consciousness, cognitive impairment, sensory and motor dysfunction, and speech disorders are observed(Dritsas, & Trigka, 2022;Li et al., 2015). Approximately 73% of patients with stroke experience a decrease in their occupational and social roles and independence due to physical and cognitive impairment. Functional impairment limits activities of daily living, which leads to further restrictions in economic activities and social participation (Oros et al., 2016;Park, & Park, 2014). Cognitive impairment not only negatively affected motor skill acquisition, memory and judgment, and quality of life but also limited autonomy in activities of daily living. In our study, we assessed the effects of an 8-week cognitive rehabilitation program on the cognitive function, depression, anxiety, and daily life activities of patients with stroke.
Koch et al. (2020) showed improvement in cognitive function in the group where cognitive training and resistance training were combined, Bo et al. (2019) reported a significant difference in cognitive function in the group combining aerobic exercise compared to the group that only intervened with aerobic exercise. Ploughman et al. (2019) assessed the effects of aerobic exercise combined with cognitive training improved cognitive function. Consistent with these findings, we observed significant improvements in cognitive function in EG treated with a combination of cognitive training and exercise therapy. Amorós-Aguilar et al. (2021) has been shown to have neurological benefits, including increased synaptic plasticity, neural circuit reorganization, and reduced secondary damage and neuronal loss, of physical exercise and physical activity on cognitive recovery after stroke. As in previous studies, complex interventions of various methods with the addition of aerobic training are required.
Kootker et al. (2020) reported that a cognitivebehavioral intervention method improved depression and corrected negative cognitive behavior in patients with stroke to promote the recovery of nerve and physical functions. MacDonald (2017) reported that regular psychological involvement combined with neurological treatment and nursing was important for improving the depressive state of patients with stroke. In another study, An, & Kim (2017) showed a significant reduction in depression in a group of patients with stroke patients who underwent a CCRP. Ahrens et al. (2023) reported significantly reduced depression and anxiety in a group of patients with stroke who received cognitive-behavioral therapy. Barrows, & Thomas (2019) also reported significant differences in depression and anxiety in a group of patients who underwent cognitive training using a tablet PC. Consistent with these results, in this study, EG who received a cognitive rehabilitation program showed a significant difference in anxiety and depression after intervention. It is thought that cognitive training combined with exercise therapy helped reduce depression and anxiety due to the reduction of negative thoughts through cognitive restructuring and neurophysiological changes.
Chen et al. (2022) reported that digital OT cognitive function training significantly improved activities of daily living in patients with stroke. Cho, & Lee (2019) reported that Head Mount Display with computerized cognitive therapy significantly improved cognitive function and activity of daily living performance in patients with stroke. In another study, Bennett et al. (2002) assessed cognitive and perceptual functions and activities of daily living in the 6-year follow-up of patients with stroke. Patients with impaired perception, spatial skills, and problem-solving abilities at baseline assessment, showed decreased basic daily activities such as moving, washing, bathing, dressing, eating, and toileting. In contrast, patients with impaired attention and memory showed reduced instrumental daily living activities. Consistent with these findings, we observed significant differences in the activities of daily living in the EG that received a cognitive rehabilitation program. Physical function affects activities of daily living. However, detailed observation and approaches that also consider cognitive function and emotional and perceptual dysfunction, including depression and anxiety help to better understand patient difficulties in specific activities of daily living and establish effective rehabilitation treatment strategies.
Ⅴ. Conclusion
This study assessed changes in cognitive function, depression, anxiety, and activities of daily life after a cognitive rehabilitation program in stroke patients. The cognitive rehabilitation program improved cognitive function and activities of daily life while decreasing depression and anxiety. This intervention method was shown to be a scientific and effective method that may be clinically valuable for the treatment of patients with stroke. Future studies are needed to conduct a more systematic and specific training program in a larger sample size to assess the effects of cognitive therapy in patients with stroke.
