Comparison of multiple interventions for older adults with Alzheimer disease or mild cognitive impairment: A PRISMA-compliant network meta-analysis

Relationships between amyloid levels, glucose metabolism, morphologic changes in the brain and clinical status of patients with Alzheimer's disease

OBJECTIVE

The current study was conducted to improve the understanding of relationships between regional cortical amyloid load, glucose metabolism, cortical morphology (volume), and severity of clinical symptoms in patients with AD, MCI, and age-matched controls.

METHODS

To objectivize the radiological evaluation of patients with suspected AD, head-to-head multi-modality imaging studies were conducted using MRI and PET/CT with [¹⁸F]FDG and [¹⁸F]AV45 for visualization and quantitation of brain morphology, glucose metabolism, and amyloid levels, respectively. A total of 84 subjects was studied, including 33 patients with AD, 31 patients with MCI, and 20 age-matched healthy controls (HC). A new quantitative index was calculated as a ratio of regional SUV of [¹⁸F]AV45 (normalized to cerebellar cortex) over the corresponding regional SUV of [¹⁸F]FDG, divided by the corresponding regional volume, measured from the co-registered MRI and normalized to the normal age-matched control group (AV45/FDG/NVol index). Relationships between clinical scores (TMSE, ADAS) and AV45/FDG/NVol indices for different structures of the brain in study groups were determined using linear regression analyses.

RESULTS

A significant direct linear correlation was observed between the AV45/FDG/NVol index and ADAS-Cog test score and an inverse correlation with TMSE score at baseline and with the degree of changes in ADAS and TMSE scores assessed one year later (disease progression). The observed correlations between AV45/FDG/NVol index and clinical scores were higher than those with MRI-based cortical volumes, FDG SUV, or cerebellum-normalized AV45 SUV alone.

CONCLUSIONS

Current study demonstrated that AV45/FDG/NVol index mapping of the brain is a novel quantitative molecular imaging biomarker that correlates with clinical neurocognitive status and may facilitate more accurate diagnosis, staging, and prognosis of AD. Additional larger scale clinical studies are required to further evaluate the efficacy of this new quantitative index as a diagnostic and prognostic biomarker of AD as well as for the evaluation of safety and efficacy of novel agents undergoing clinical trials for therapy of AD.

Four-month treadmill exercise prevents the decline in spatial learning and memory abilities and the loss of spinophilin-immunoreactive puncta in the hippocampus of APP/PS1 transgenic mice

BACKGROUND

Previous studies have reported that exercise could improve the plasticity of hippocampal synapses. However, the effects of exercise on synapses in the hippocampus in Alzheimer's disease (AD) are not completely known.

METHODS

In this study, thirty 12-month-old male APP/PS1 double transgenic mice were randomly divided into a sedentary group (n = 15) and a running group (n = 15). Fifteen 12-month-old male wild-type littermates were assigned to the control group (n = 15). While running mice were assigned to treadmill running for four months, the control mice and sedentary mice did not run during the study period. After Morris water maze testing, five mice in each group were randomly selected for a stereological assessment of spinophilin-immunoreactive puncta in the CA1, CA2-3 and dentate gyrus (DG) of the hippocampus.

RESULTS

Morris water maze testing revealed that while the learning and memory abilities in sedentary APP/PS1 mice were significantly worse than those in wild-type control mice, the learning and memory abilities in running APP/PS1 mice were significantly better than those in sedentary APP/PS1 mice. The stereological results showed that the spinophilin-immunoreactive puncta numbers of the CA1, CA2-3 and DG in the hippocampus of sedentary APP/PS1 mice were significantly lower than those of wild-type control mice and that the numbers of these spines in the CA1, CA2-3 and DG in the hippocampus of running APP/PS1 mice were significantly higher than those of sedentary APP/PS1 mice. Moreover, a running-induced improvement in spatial learning and memory abilities was significantly correlated with running-induced increases in the spinophilin-immunoreactive puncta numbers in the CA1 and DG of the hippocampus.

CONCLUSIONS

Four-month treadmill exercise induced a significant improvement in spatial learning and memory abilities and a significant increase in the number of spinophilin-immunoreactive puncta of the CA1, CA2-3 and DG in the hippocampus of APP/PS1 mice. Running-induced improvements in spatial learning and memory abilities were significantly correlated with running-induced increases in the spinophilin-immunoreactive puncta numbers in the CA1 and DG of the hippocampus.

Pathways of Prevention: A Scoping Review of Dietary and Exercise Interventions for Neurocognition

Alzheimer's disease and related dementias (ADRD) represent an increasingly urgent public health concern, with an increasing number of baby boomers now at risk. Due to a lack of efficacious therapies among symptomatic older adults, an increasing emphasis has been placed on preventive measures that can curb or even prevent ADRD development among middle-aged adults. Lifestyle modification using aerobic exercise and dietary modification represents one of the primary treatment modalities used to mitigate ADRD risk, with an increasing number of trials demonstrating that exercise and dietary change, individually and together, improve neurocognitive performance among middle-aged and older adults. Despite several optimistic findings, examination of treatment changes across lifestyle interventions reveals a variable pattern of improvements, with large individual differences across trials. The present review attempts to synthesize available literature linking lifestyle modification to neurocognitive changes, outline putative mechanisms of treatment improvement, and discuss discrepant trial findings. In addition, previous mechanistic assumptions linking lifestyle to neurocognition are discussed, with a focus on potential solutions to improve our understanding of individual neurocognitive differences in response to lifestyle modification. Specific recommendations include integration of contemporary causal inference approaches for analyzing parallel mechanistic pathways and treatment-exposure interactions. Methodological recommendations include trial multiphase optimization strategy (MOST) design approaches that leverage individual differences for improved treatment outcomes.

Expert Consensus on the Care and Management of Patients with Cognitive Impairment in China

The cognitive disease consensus was prepared by panels of health and public representatives based on actual clinical practice in Geriatric Departments in Chinese hospitals and a systematic literature review. This consensus reflects the medical knowledge accumulated by those experts and provides information about professional medical care and advice. A multidisciplinary panel of specialists (neurologists, psychiatrists, and nursing specialists) reports an expert consensus on the medical knowledge accumulated from those experts and provides information about professional medical care and advice. The recommendations focus on the care and management of older adults with mild cognitive impairment, the objectives and methods of maintaining cognition and training, the assessments and measures of daily care for patients at different stages of dementia, the assessments and coping strategies for the behavioral and psychological symptoms of dementia, principles and suggestions for an appropriate living environment, arrangements for recreational activities, the care and management of patients with end-stage dementia, and suggestions for addressing stress in caregivers.

A 4-Item Case-Finding Tool to Detect Dementia in Older Persons

OBJECTIVES

Brief cognitive tests are recommended in clinical services outside of specialized memory clinics as case-finding tools to reduce the diagnostic gap of dementia. Although the Montreal Cognitive Assessment (MoCA) is among the most widely used brief tests in specialized memory clinics, its length precludes routine use in nonspecialty clinics. This study investigated whether a small subset of MoCA would suffice to match the performance of the full MoCA in detecting dementia and, hence, be useful in nonspecialty clinics.

DESIGN

Cross-sectional test research.

SETTING

Alzheimer's Disease Centers across the United States.

PARTICIPANTS

Participants age ≥65 years (n = 8773).

MEASURES

Participants completed MoCA and were evaluated for dementia. The study sample was split into 2: the derivation sample (n = 4386) was used to develop a short variant of MoCA that best distinguish dementia (using the best-subset-approach with 10-fold cross-validation), while the validation sample (n = 4387) verified its actual performance using area under the receiver operating characteristic-curve (AUC).

RESULTS

A 4-item cognitive test was identified, comprising Clock-drawing, Tap-at-letter-A, Orientation, and Delayed-recall. It demonstrated excellent performance in distinguishing dementia from nondementia (AUC 94.2%) and was comparable to that of MoCA (AUC 93.8%), even across education subgroups. It explained 85.9% of the variability in MoCA and had scores that could be mapped to MoCA with reasonable precision. At the optimal cut-off score of <10, it demonstrated 87.9% sensitivity and 87.6% specificity in detecting dementia.

CONCLUSIONS AND IMPLICATIONS

Using rigorous methods, this study developed a brief cognitive test that is free of charge, takes <5 minutes to complete, covers the key cognitive domains, and has standardized instructions to allow its administration even by nonphysicians. This brief test is well suited as a case-finding tool in nonspecialty clinics (such as in primary care and geriatric clinics) and may improve care-integration with specialized memory clinics that utilize MoCA.

Non-pharmacological therapeutic strategy options for patients with dementia based on cognitive function-A Bayesian network meta-analysis of randomized controlled trials

Dementia represents one of the most common neurodegenerative disorders in older adults. However, it is still unclear whether non-pharmacological therapies (NPTs) are effective or not and which treatment should be preferred. We applied a series of search strategies to identify eligible randomized controlled trials on 1st October, 2018, investigating the effects of NPTs of dementia in the older persons. Pairwise and network meta-analyses were sequentially performed. A total of 31 trials were included, which enrolled 1895 participants and 7 NPTs. Compared with control group, all the NPTs included were statistically beneficial to cognitive function, and our study indicated Comprehensive Therapy(CT) [the surface under the cumulative ranking curve (SUCRA = 92.42%)] might be the best choice for dementia patients. Our study suggests CT might be the optimal NPT for improving the cognitive function of dementia patients. However, the above conclusions need to be further analyzed.

Effectiveness of Exercise Programs on Patients with Dementia: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Exercise programs have been introduced to improve cognitive function, whereas studies showed inconsistent results regarding the effectiveness of exercise programs on patients with dementia. This study aimed to summarize randomized controlled trials (RCTs) to assess the effect of exercise programs on cognition, activities of daily living (ADL), and depression in elderly with dementia. We systematically screened PubMed, Embase, and the Cochrane library for relevant studies throughout November 21, 2018. The pooled standardized mean differences (SMDs) with 95% confidence intervals (CIs) were employed to calculate cognition, ADL, and depression by using random-effects model. A total of 20 RCTs with 2,051 dementia patients were included in final quantitative meta-analysis. There were no significant differences between exercise programs and control regarding cognition (SMD: 0.44; 95% CI: -0.21-1.09; P=0.183), ADL (SMD: 0.50; 95% CI: -0.03-1.02; P=0.066), and depression (SMD: -0.43; 95% CI: -0.90-0.05; P=0.077). Sensitivity analysis results indicated that exercise programs might play an important role in cognition and ADL, whereas the depression level was unaltered by the exclusion of any particular study. Subgroup analyses indicated that exercise programs were associated with increased cognitive levels if the mean age of patients was <80.0 years when compared with usual care and studies with low quality. Moreover, the ADL level was significantly increased in patients receiving exercise programs versus usual care. These results suggested that exercise programs might play an important role in cognition and ADL in patients with dementia. These results required further verification by large-scale RCTs, especially for depression outcomes.

Effect of nutrition on neurodegenerative diseases. A systematic review

Neurodegenerative diseases are characterized by the progressive functional loss of neurons in the brain, causing cognitive impairment and motoneuron disability. Although multifactorial interactions are evident, nutrition plays an essential role in the pathogenesis and evolution of these diseases. A systematic literature search was performed, and the prevalence of studies evaluated the effect of the Mediterranean diet (MeDiet), nutritional support, EPA and DHA, and vitamins on memory and cognition impairment. The data showed that malnutrition and low body mass index (BMI) is correlated with the higher development of dementia and mortality. MeDiet, nutritional support, and calorie-controlled diets play a protective effect against cognitive decline, Alzheimer's disease (AD), Parkinson disease (PD) while malnutrition and insulin resistance represent significant risk factors. Malnutrition activates also the gut-microbiota-brain axis dysfunction that exacerbate neurogenerative process. Omega-3 and -6, and the vitamins supplementation seem to be less effective in protecting neuron degeneration. Insulin activity is a prevalent factor contributing to brain health while malnutrition correlated with the higher development of dementia and mortality.

Perspective: Network Meta-analysis Reaches Nutrition Research: Current Status, Scientific Concepts, and Future Directions

Traditional pairwise meta-analysis (PMA) is a very useful method that pools evidence from one study design type if appropriate; its widespread use in nutrition research is an important phenomenon. Recently, a promising method for more advanced evidence-synthesis, called network meta-analysis (NMA), was introduced. NMA is an extension of PMA that enables simultaneous comparison of multiple interventions. NMA combines direct evidence (i.e., trials comparing 2 interventions directly) and indirect evidence (i.e., from a connected route via ≥1 comparators, e.g. placebo) in a network of studies. NMAs have the potential to advance knowledge in the field of nutrition as they provide insights that cannot be obtained by individual 2-arm randomized controlled trials or PMA. Thus, in this perspective paper, we aim to summarize the current (methodologic) status of published NMAs in nutrition research and emphasize advances and strengths in comparison with traditional PMA through specific examples, and highlight potential pitfalls and limitations. NMA is an emerging methodology in the field of nutrition research. A PubMed search identified only 23 nutrition research-related NMAs published since the inception of journals up to January 8, 2019 (61% of them published since 2017), compared with >5000 published PMAs. Moreover, we aim to highlight the scientific concepts and standards through the use of the following NMA example: "Which type of oils/solid fats offers the greatest impact on blood lipids?" In this regard, we discuss intervention definitions, transitivity/similarity, statistical methods, description and visualization of results, inconsistency, ranking, dissemination bias, assessing the certainty of evidence by Grading of Recommendations Assessment, Development and Evaluation, and reporting guidelines. We expect that rigorously conducted NMAs based on high-quality systematic reviews will become the new evidence synthesis benchmark in nutrition research. However, caution is warranted because abuse and misinterpretations of PMA and NMA findings could hamper the scientific field and possibly decision-making regarding public policy.

Relative Efficacy of a Nutritional Intervention on Cognitive Performance Across the Adult Lifespan and During Early Cognitive Decline

A nutritional supplement has maintained or improved cognitive performance for healthy adults and individuals with mild cognitive impairment (MCI). Performance varied between 93 healthy adults aged 18-73 years versus 43 aged 75-85 years and among individuals with MCI. Healthy adult performance was stratified by age and for MCI as "intact" or "impaired" (Dementia Rating Scale guidelines). Some older individuals performed as well as younger individuals. All intact individuals with MCI maintained baseline performance; only impaired individuals receiving the supplement maintained baseline performance. Variation among elderly individuals can preclude observation of efficacy. Supplementation may maintain rather than improve performance for some individuals.

Cognitive effects of dance-movement intervention in a mixed group of seniors are not dependent on hippocampal atrophy

Dance-movement intervention (DMI) offers multi-component stimulation of cognitive functions, and it may ameliorate cognitive deficits in the elderly. We investigated the effects of intensive DMI on the cognitive performances of healthy seniors (HS) and patients with mild cognitive impairment (MCI). In addition, we evaluated whether the baseline MRI hippocampus-to-cortex volume (HV:CTV) ratio (i.e., a marker of a typical AD-specific brain atrophy and of distribution of neurofibrillary tangles in the brain) has any impact on the DMI-induced cognitive changes. The research cohort consisted of 99 subjects who were randomly assigned (in a 1:1 ratio) to a DMI group or to a control (life-as-usual) group. The DMI group consisted of 49 subjects with an average age of 69.16 years (SD = 5.36), of which 34 were HS (69.4%) and 15 had MCI (30.6%). The control group consisted of 50 subjects aged 68.37 years (SD = 6.10), of which 31 were HC (62%) and 19 (38%) had MCI. The DMI group underwent a 6-month intervention, which consisted of 60 lessons supervised by a qualified instructor. Statistical analysis yielded a significant improvement of the figural fluency task as measured by the five-point test in the DMI group as compared to the control group [t (97) = 2.72; p = 0.008]. The baseline HV:CTV ratio was not associated with cognitive changes on that task or with changes in any cognitive domain's Z scores. We observed DMI-induced effect on the test evaluating executive functions across the spectrum of HS and MCI, which was not dependent on the magnitude of AD-related brain pathology.

Developing a Brief Neuropsychological Battery for Early Diagnosis of Cognitive Impairment

OBJECTIVES

Early diagnosis of cognitive impairment is increasingly emphasized in the literature to facilitate timely preventive interventions. Although bedside cognitive tests such as the Montreal Cognitive Assessment (MoCA) are widely used for such early diagnostic purposes, they may not have comparable performance to a full neuropsychological battery (FNB) in diagnosing early cognitive impairment. This study investigated whether a small subset of neuropsychological tests can be added on to MoCA to match its performance to that of the FNB in discriminating mild cognitive impairment and dementia (MCI/dementia) from normal cognition.

DESIGN

Cross-sectional diagnostic study.

SETTING

Alzheimer's Disease Centers across the United States.

PARTICIPANTS

Older participants (≥50 years) who completed MoCA and the FNB (N = 9187).

MEASURES

The study sample was split into two: the derivation sample (n = 1837) was used to develop a brief neuropsychological battery that best discriminated MCI/dementia (using the best-subset approach with 10-fold cross-validation); while the validation sample (n = 7350) verified its actual performance in discriminating MCI/dementia.

RESULTS

A 3-item neuropsychological battery was identified, comprising MoCA, Benson Complex Figure Recall, and Craft Story 21 Delayed Recall. It had excellent performance in discriminating MCI/dementia from normal cognition (area under the receiver operating characteristic curve [AUROC] 90.0%, 95% confidence interval [CI] 89.2%-90.7%), which was comparable to that of the FNB (AUROC 88.4%, 95% CI 87.6%-89.2%). By contrast, MoCA alone had significantly worse AUROC (86.9%, 95% CI 86.0%-87.7%) than that of the FNB.

CONCLUSIONS/IMPLICATIONS

Using rigorous methods, this study developed a brief neuropsychological battery that maintained the brevity of a bedside cognitive test, while rivaling the diagnostic performance of an FNB in early cognitive impairment. This brief battery offers a viable alternative when the FNB is needed but cannot be feasibly administered in nonspecialty clinics. It can have a wider health systems effect of improving patients' access to accurate diagnosis in early cognitive impairment and facilitating timely interventions to delay the progression of cognitive impairment.

The Optimal Short Version of Montreal Cognitive Assessment in Diagnosing Mild Cognitive Impairment and Dementia

OBJECTIVES

While various short variants of the Montreal Cognitive Assessment (MoCA) have been developed, they have not been compared among each other to determine the most optimal variant for routine use. This study evaluated the comparative performance of the short variants in identifying mild cognitive impairment or dementia (MCI/dementia).

DESIGN

Baseline data of a cohort study.

SETTING

Alzheimer's Disease Centers across the United States.

PARTICIPANTS

Participants aged ≥50 years (n = 4606), with median age 70 (interquartile range 65-76).

MEASURES

Participants completed MoCA and were evaluated for MCI/dementia. The various short variants of MoCA were compared in their performance in discriminating MCI/dementia, using areas under the receiver operating characteristic curve (AUCs).

RESULTS

All 7 short variants of MoCA had acceptable performance in discriminating MCI/dementia from normal cognition (AUC 87.7%-91.0%). However, only 2 variants by Roalf et al (2016) and Wong et al (2015) demonstrated comparable performance (AUC 88.4-88.9%) to the original MoCA (AUC 89.3%). Among the participants with higher education, only the variant by Roalf et al had similar AUC to the original MoCA. At the optimal cut-off score of <25, the original MoCA demonstrated 84.4% sensitivity and 76.4% specificity. In contrast, the short variant by Roalf et al had 87.2% sensitivity and 72.1% specificity at its optimal cut-off score of <13.

CONCLUSIONS/IMPLICATIONS

The various short variants may not share similar diagnostic performance, with many limited by ceiling effects among participants with higher education. Only the short variant by Roalf et al was comparable to the original MoCA in identifying MCI or dementia even across education subgroups. This variant is one-third the length of the original MoCA and can be completed in <5 minutes. It provides a viable alternative when it is not feasible to administer the original MoCA in clinical practice and can be especially useful in nonspecialty clinics with large volumes of patients at high risk of cognitive impairment (such as those in primary care, geriatric, and stroke prevention clinics).

The optimal treatment for improving cognitive function in elder people with mild cognitive impairment incorporating Bayesian network meta-analysis and systematic review

It's widely acknowledged that, as a neurodegenerative aging disease representing an intermediate stage between cognitive intactness and Alzheimer's disease (AD), Mild cognitive impairment (MCI) poses an excessive burden on patients' well-being, family members, health-care providers as well as the whole society. This study focuses on three cognitive interventions proposed by Clare and Woods, which are, Cognitive stimulation (CS), Cognitive training (CT) and Cognitive rehabilitation (CR). Our Network meta-analysis (NMA) aims to compar them with one another to determine the optimal cognitive intervention for elderly adults with MCI in improving their cognitive function. We applied extensive strategies to preliminary literature retrieval to identify relevant randomized controlled trials (RCTs) which scrupulously compared any two of the three cognitive interventions with one another or any one of the three with a control group as the placebo or non-active group in treating elder patients with MCI in accordance with Petersen's criteria. Our NMA of cognitive interventions for patients diagnosed with MCI appraised the relative effectiveness of cognitive interventions across trials simultaneously. Our study attempts to summarize available data to suggest that CS (Mean difference [MD] = 0.95, 95% confidence interval [CI]:0.27, 1.70) and CT (MD = 0.70, [CI]:0.11,1.30) were significantly beneficial to MCI patients for improving their cognition status while CR (MD = 0.59, [CI]:-0.30,1.50) scored lowest. Our study suggested CS was most likely to be the best intervention for improving the cognitive function of MCI patients.

Three months of multimodal training contributes to mobility and executive function in elderly individuals with mild cognitive impairment, but not in those with Alzheimer's disease: A randomized controlled trial

OBJECTIVE

To investigate the effects of a 12-week multimodal physical exercise program on global cognition, executive function and mobility in elderly people with mild cognitive impairment (MCI) or Alzheimer's disease (AD).

DESIGN

Randomized controlled trial (RCT) of two groups in parallel; single-blind.

METHOD

Patients were allocated to a control group (CG; n = 28 comprising MCI = 14 and AD = 14) and an exercise group (EG; n = 28 comprising MCI = 14 and AD = 14). The participants' physical and cognitive abilities were evaluated before and three months after the intervention. The training consisted of a 1-hour supervised program of multimodal physical exercises (aerobic, strength, balance and flexibility) of moderate intensity, delivered twice a week.

RESULTS

The independent t-test of the delta (Δ = post-intervention - pre-intervention) was used to compare the groups (CG x EG) for each diagnosis (MCI and AD). There was a significant difference only in the simple task mobility test (ΔCG: -0.18 ± 0.53; ΔEG: -1.05 ± 0.57; P =  0.03) and in the verbal fluency (ΔCG: -1.30 ± 2.49; ΔEG: 3.16 ± 1.72, P =  0.05) of the elderly with MCI, showing a beneficial effect of the multimodal exercise in this group.

CONCLUSION

Our findings indicate that a 12-week multimodal physical exercise program contributed to improvements in the mobility and executive function of elderly individuals with MCI, but not of those with AD. Although more RCTs are needed, physical exercise should be recommended to those in the early stages of neurocognitive disorder.

Experimental effects of exercise on memory function among mild cognitive impairment: systematic review and meta-analysis

OBJECTIVE

The objective of this study was to evaluate the experimental effects of exercise on memory function among adults with mild cognitive impairment (MCI).

METHODS

A systematic review and meta-analysis were employed. Studies were identified using electronic databases, including PubMed, PsychInfo, SPORTDiscus, and Google Scholar. To be eligible for inclusion, studies had to employ an experimental design, be conducted in humans (no animal models) with mild cognitive impairment, include an exercise intervention arm (either acute exercise or chronic training), and measure memory function (any type) as the outcome measure. Comprehensive Meta-Analysis software was used to compute the standardized mean difference effect size (Cohen's d) and 95% CI using a random-effects model.

RESULTS

In total, 11 studies met our criteria, contributing to 20 effect size estimates. Among the 20 effect size estimates, 13 contributed to a short-term memory recall, with 7 contributing to a delayed/long-term memory recall. The overall weighted mean effect size was d = 0.30 (95% CI: 0.16-0.44; P < 0.001), indicating a small to medium effect of exercise on improving memory function. For the moderation analysis, there was no evidence of a moderation effect for recall duration (Q = 0.004, df(1), P = 0.95), as exercise (vs. control) demonstrated both short-term (d = 0.31; 95% CI: 0.14-0.47; P < 0.001) and long-term memory (d = 0.29; 95% CI: 0.06-0.53; P = 0.013) benefits.

CONCLUSION

Current evidence suggests that exercise may help to improve memory function among those with MCI. Safe and progressive forms of exercise should be promoted among MCI patients.

Mild cognitive impairment: A concept analysis

AIM

To clarify the concept of mild cognitive impairment (MCI) and identify its attributes to enhance understanding of its implications for nursing practice and research.

BACKGROUND

MCI is a concept that has evolved, thus clarification of this concept is essential for the advancement of nursing science.

DESIGN

Walker and Avant's eight steps of concept analysis strategy was used.

DATA SOURCE

Manuals of mental disorders and databases such as PubMed, Springer, PsychINFO, Cumulative Index to Nursing and Allied Health Literature, and Education Resources Information Center (ERIC) from 1982 to 2018.

REVIEW METHODS

A literature search was conducted using keywords such as "mild," "cognitive," "impairment," and "deterioration."

RESULTS

The concept of MCI is defined as the transitional state between cognitive state normal for age and the early manifestation of dementia states. It is characterized by the presence of objective and subjective evidence of impairment in one or multiple cognitive domains, independence in daily activities, can be reversible, and is a risk factor for dementia.

CONCLUSIONS

Clarification of MCI serves as a framework for identification, treatment, and interventions that may support healthy aging in older adults.

Immediate Intervention Effects of Standardized Multicomponent Group Interventions on People with Cognitive Impairment: A Systematic Review

BACKGROUND

There is no curative medical treatment for dementia. Therefore, researchers turned their attention to non-pharmacological treatment approaches. Many reviews analyzed the efficacy of single-component interventions, but there has been no systematic review of multicomponent interventions so far.

OBJECTIVE

The aim was to systematically review studies using standardized multicomponent group interventions for persons with dementia or persons with mild cognitive impairment (MCI) and to analyze their immediate intervention effects.

METHODS

The databases PubMed, PsycINFO, PSYNDEX, and CINAHL were systematically searched. We included randomized controlled trials with people with MCI or dementia, which implemented interventions with at least two components that targeted different outcome domains. Additionally, the intervention had to be standardized and in a group setting.

RESULTS

Nine studies met the inclusion criteria with a total sample size of N = 513 participants. Six studies applied two, two studies applied three, and one study applied four components. Four studies, which combined at least a physical and a cognitive component, had a positive effect on non-cognitive symptoms of dementia. Two of these interventions additionally had a positive effect on cognitive abilities. One study reported a positive effect on activities of daily living and another study showed an effect on quality of life.

CONCLUSION

In spite of the heterogeneity of the studies, multicomponent interventions suggest a positive effect on non-cognitive symptoms, especially the combination of cognitive and physical components. Single studies had also an effect on additional outcome domains. By trend the effects are dependent on application rate and used assessments.

Comparison of Cognitive Intervention Strategies for Older Adults With Mild to Moderate Alzheimer's Disease: A Bayesian Meta-analytic Review

OBJECTIVES

We aimed to identify the best form of cognitive therapy among 3 main cognitive interventions of Alzheimer's disease (AD) including cognitive training (CT), cognitive stimulation (CS), and cognitive rehabilitation (CR).

DESIGN

Systematic review and Bayesian network meta-analysis.

SETTING AND PARTICIPANTS

An exhaustive literature search was conducted based on PubMed, Embase, the Cochrane Central Register of Controlled Trials, PsycINFO, the China National Knowledge Infrastructure database, the Chinese Biomedical Literature database, the Wan Fang database, and Web of Science and other database and randomized controlled trials were identified from their inception to May 1, 2018. Older adult participants diagnosed with AD were recruited.

MEASURES

We conducted a Bayesian network meta-analysis (NMA) to rank the included treatments. Cognitive functions were measured based on the Mini-Mental State Examination (MMSE). A series of analyses and assessments, such as the Pairwise meta-analysis and the risk of bias, were performed concurrently.

RESULTS

Only 22 studies were included in our analysis based on a series of rigorous screenings, which comprised 1368 participants. No obvious heterogeneities were found in NMA (I² = 32.7%, P = .07) after the data were pooled. The mean difference (MD) of CT [MD = 2.1, confidence interval [CI]: 1.0, 3.2), CS (MD = 0.92, CI: -0.20, 2.0), and CR (MD = 2.0, CI: 0.73, 3.4) showed that CT and CR could significantly improve cognitive function as measured by MMSE in the treatment group whereas the CS was less effective. CT had the highest probability among the 3 cognitive interventions [the surface under the cumulative ranking curve (SUCRA) = 84.7%], followed by CR (SUCRA = 50.0%) and CS (SUCRA = 47.4%).

CONCLUSIONS/RELEVANCE

Our study indicated that the CT might be the best method for improving the cognitive function of AD patients. The findings from our study may be useful for policy makers and service commissioners when they make choices among different alternatives.

The Enhanced Interactive Physical and Cognitive Exercise System (iPACESTM v2.0): Pilot Clinical Trial of an In-Home iPad-Based Neuro-Exergame for Mild Cognitive Impairment (MCI)

Given increasing longevity worldwide, older adults and caregivers are seeking ways to curb cognitive decline especially for those with mild cognitive impairment (MCI, now mild neurocognitive disorder, mNCD, Diagnostic and Statistical Manual of Mental Disorders, 5th ed. (DSM-V). This quasi-experimental, within-subjects pilot clinical trial was designed to replicate and extend the study of cognitive benefits for MCI by improving upon our prior interactive Physical and Cognitive Exercise Study (iPACESTM v1.0) by increasing the usability of the neuro-exergame and exploring possible underlying neurobiological mechanisms. Older adults were enrolled in a three-month, in-home trial of a portable neuro-exergame (iPACES™ v2.0) where participants pedaled and steered along a virtual bike path (Memory Lane™). Neuropsychological function was assessed at baseline after component familiarization intervals (e.g., two weeks of exercise-only, game-only, etc.) and after three months of interactive neuro-exergame intervention. Fourteen participants were enrolled in the study and seven completed the final evaluation. Intent-to-treat analyses were conducted with imputed missing data (total n = 14). Significant improvement in executive function (Stroop) was found (d = 0.68, p = 0.02) only. Changes in salivary biomarkers (cortisol and insulin-like growth factor 1; IGF-1) were significantly associated with improved cognition. Further research is needed, but pilot data suggest that a portable in-home neuro-exergame may be an additional, practical tool to fight back against cognitive decline and dementia.