Optimizing the physical activity intervention for older adults with mild cognitive impairment: a factorial randomized trial.

Background: Physical activity (PA) intervention is one of the most effective interventions to promote cognitive function of older adults with mild cognitive impairment (MCI). However, the level of PA remains low. Based on the two core interventions (X-CircuiT and health education), this study aimed to examine the effect of three implementation strategies (viz., role modeling, goal-setting, and reminding) on the PA level among older adults with MCI using the multiphase optimization strategy (MOST). Methods: Participants were randomized into one of eight conditions in a factorial design involving three factors with two levels: (i) role modeling (on vs. off); (ii) goal-setting (on vs. off); and (iii) reminding (on vs. off). The primary outcome was PA level at 12 weeks. The secondary outcomes were cognitive function, self-efficacy, and cost-effectiveness at 12 weeks. The intention-to-treat (ITT) analysis was performed as the main analysis and the per-protocol (PP) analysis as the sensitivity analysis. Results: A total of 107 participants were included and randomly assigned into three groups, each receiving different implementation strategies. The results of the multivariate regression analysis showed that the three implementation strategies, namely, reminding (B = 0.31, p < 0.01), role modeling (B = 0.21, p < 0.01), and goal-setting (B = 0.19, p < 0.01), could significantly improve PA level. Specifically, it was found that role modeling (B = 0.68, p = 0.03) could significantly improve cognitive function. There were no significant interactions among the three implementation strategies. Role modeling was the most cost-effective strategy, costing 93.41 RMB for one unit of PA. Conclusions: Role modeling was likely to be the best implementation strategy. The value-based and cost-effective PA intervention package could include the core intervention (X-CircuiT and health education) and implementation strategy (role modeling). Clinical Trial Registration: https://www.chictr.org.cn, The study was retrospectively registered on 30 June 2022 (ChiCTR2200061693).

Effectiveness and acceptability of non-pharmacological interventions in people with mild cognitive impairment: Overview of systematic reviews and network meta-analysis.

BACKGROUND: To explore effectiveness and acceptability of non-pharmacological interventions in mild cognitive impairment (MCI). METHODS: Overview of systematic reviews and network meta-analysis were conducted. Systematic reviews (SRs) were searched via seven databases from June 2015 to June 2020. Randomized controlled trials (RCTs) were retrieved. The Methodological quality was assessed by AMSTAR 2 and RoB 2. Outcomes were effectiveness and acceptability measured by standardized mean differences (SMDs) and odd ratios (ORs) with 95% confidence interval (CI). Pairwise meta-analysis was first conducted, followed by network meta-analysis. RESULTS: A total of 22 SRs and 42 RCTs with 4401 participants were included. The methodological quality of included SRs and RCTs were moderate. There were four interventions, with three types of physical activity (aerobic, muscle-strengthening, and mind-body), three types of cognitive (rehearsal-based, compensatory, and mixed), multicomponent (physical and cognitive component), and nutrition intervention. No significant inconsistency was identified. Regarding intervention effectiveness, muscle-strengthening (SMDs 0.87, 95% CI 0.31-1.43; rank 1), mind-body (0.76, 0.38-1.14; rank 2) and aerobic (0.34, 0.13-0.50; rank 3) were significantly better than the control group and there was no significant difference among these types of intervention . Cognitive intervention of rehearsal-based (1.33, 0.30-2.35; rank 1) and mixed (0.55, 0.00-1.11; rank 2) were significantly better than the control group and there was no significant difference among these types of intervention. Multicomponent intervention (0.32, 0.02-0.62) were significantly better than the control group but not better than the single component group. Regarding acceptability, there was no significant difference among types of intervention. CONCLUSION: Physical activity, cognitive, and multicomponent intervention could be provided regardless of their types and acceptability due to their effectiveness on improved cognitive function for people with MCI.

Derivation and Validation of the Cognitive Impairment Prediction Model in Older Adults: A National Cohort Study.

Objective: This prediction model quantifies the risk of cognitive impairment. This aim of this study was to develop and validate a prediction model to calculate the 6-year risk of cognitive impairment. Methods: Participants from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) 2008-2014 and 2011-2018 surveys were included for developing the cognitive impairment prediction model. The least absolute shrinkage and selection operator, clinical knowledge, and previous experience were performed to select predictors. The Cox proportional hazard model and Fine-Gray analysis adjusting for death were conducted to construct the model. The discriminative ability was measured using C-statistics. The model was evaluated externally using the temporal validation method via the CLHLS 2002-2008 survey. A nomogram was conducted to enhance the practical use. The population attributable fraction was calculated. Results: A total of 10,053 older adults were included for model development. During a median of 5.68 years, 1,750 (17.4%) participants experienced cognitive impairment. Eight easy-to-obtain predictors were used to develop the model. The overall proportion of death was 43.3%. The effect of age on cognitive impairment reduced after adjusting the competing risk of death. The Cox and Fine-Gray models showed a similar discriminative ability, with average C-statistics of 0.71 and 0.69 in development and external validation datasets, respectively. The model performed better in younger older adults (65-74 years). The proportion of 6-year cognitive impairment due to modifiable risk factors was 47.7%. Conclusion: This model could be used to identify older adults aged 65 years and above at high risk of cognitive impairment and initiate timely interventions on modifiable factors to prevent nearly half of dementia.

Dose-response relationship in non-pharmacological interventions for individuals with mild cognitive impairment: A systematic review and meta-analysis of randomised controlled trials.

BACKGROUND: Non-pharmacological interventions (NPIs) are important in cognitive decline prevention in individuals with mild cognitive impairment (MCI). However, the dose-response relationship remains unclear. DESIGN: Systematic review and meta-analysis of randomised controlled trials. METHODS: Seven databases were searched until April 2020. RCTs of NPIs in individuals with MCI were eligible for inclusion. Hedge's g was used to calculate the effect size. A random-effect meta-analysis was used to explore the impact of NPIs on cognition. Subgroup analysis was used to investigate the moderates. The dose was measured by prescription (frequency, intensity, type, time and volume) and intervention characteristics (period, energy expenditure, delivery mode and setting) in NPIs. RESULTS: Forty-two studies with 4401 participants were included. In the NPIs, cognitive intervention (g = 0.167), physical exercise (g = 0.536) and multicomponent intervention (g = 0.386) had significant effect on cognition in individuals with MCI. Dose-response results showed cognition could be significantly improved in 1-2 times/week (p < .05), 60-120 min/session (p < .05), ≥12 weeks (p < .05), supervised (p < .05), clinical setting (p < .05) in cognitive intervention. In physical exercise, cognition could be improved in ≥3 times/week (p < .05), vigorous-intensity (p < .05), muscle-strengthening activity (p < .05), 30-60 min/session (p < .05), 6-12 weeks (p < .05), unsupervised (p < .05), community setting (p < .05). In the multicomponent intervention, cognition could be improved in 1-2 times/week (p < .05), 30-60 min/session (p < .05), 8-16 weeks (p < .05), clinical (p < .05). In nutrition intervention, cognition could be better improved DHA (p < .05), >1000 mg/day (p < .05). CONCLUSIONS: The effectiveness of cognitive intervention is significantly influenced by frequency, time, period, delivery mode and setting. The effectiveness of physical exercise is significantly influenced by frequency, intensity, type, time, period, delivery mode and setting. The effectiveness of multicomponent intervention is significantly influenced by frequency, time, period and setting. The effectiveness of nutrition intervention is significantly influenced by dose and type. RELEVANCE TO CLINICAL PRACTICE: The research summarised the evidence to guide the best prescription of NPIs and helped clinicians design more effective interventions in individuals with MCI.