Randomized controlled trial on the efficacy of a multilevel non-pharmacologic intervention in older adults with subjective memory decline: design and baseline findings of the E.Mu.N.I. study

Targeting brain health in subjective cognitive decline: insights from a multidomain randomized controlled trial

BACKGROUND

Multidomain lifestyle interventions are a promising approach to prevent cognitive decline, but their effects in subjective cognitive decline (SCD) remain controversial. We investigated the effects of lifestyle interventions on cognition and brain integrity in these at-risk individuals.

METHODS

One-hundred twenty-eight older adults with SCD were randomly assigned to either Active Control Intervention (ACI), i.e. health education; Partial Intervention (PI), i.e. tramiprosate supplementation (100 mg/die) and dietary advice; or Multilevel Intervention (MI), i.e. PI plus computerized cognitive training and physical exercise, for one year. Neuropsychological assessment and MRI were performed at baseline and at 1-year follow-up. Analyses of covariance were used to measure the effects of interventions on predefined outcomes.

RESULTS

The MI group significantly improved in attention-executive functioning (p = 0.003) compared to ACI (Cohen's d: 0.47, 95% CI 0.13-0.79). In addition, depressive symptoms (Cohen's d: - 0.48, 95% C.I. - 0.81 to - 0.14) and memory concerns (Cohen's d: - 0.77, 95% C.I. - 1.12 to - 0.41) decreased in the MI and PI respectively, relative to the ACI. The MI group also showed increased resting-state (i.e., intrinsic) brain activity in the right fronto-parietal executive network. No significant intervention effects on brain structural or vascular outcomes were found.

CONCLUSION

The study shows that a multidomain lifestyle intervention can enhance attention-executive function, ameliorate depressive symptoms and increase functional connectivity in SCD. These findings support the role of lifestyle interventions in public health strategies to mitigate cognitive decline risk.

TRIAL REGISTRATION

The trial has been registered at the United States National Library of Medicine at the National Institutes of Health Registry of Clinical Trials under the code NCT04744922 on December 9th, 2017 ( https://www.

CLINICALTRIALS

gov/ct2/show/NCT03382353 ).

Research hotspots and nursing inspiration in research of older adults with subjective cognitive decline from 2003 to 2023: A bibliometric analysis

Objectives

There has been a significant increase in subjective cognitive decline (SCD) studies in older adults over the years. A bibliometric analysis was conducted to demonstrate the current hotspots and emerging trends in SCD research in older adults and provide references for further research in this field.

Methods

The study conducted a bibliometric analysis based on co-citation analysis. From the Web of Science Core Collection database, this study obtained 1,436 manuscripts regarding SCD in older adults published from 2003 to 2023. Software CiteSpace was used to analyse the results for countries, institutions, authors, journals, keywords, top-cited papers, and burst citations scientifically and intuitively.

Results

Our result showed an overall upward trend in the volume of publications on SCD in the elderly population, suggesting that the study of SCD in older adults has attracted the attention of researchers. The United States dominates this research field, followed by China and France. The top three institutions were the University of California System, Institut National de la Sante et de la Recherche Medicale (Inserm), and UDICE-French Research Universities. Frank Jessen, Han Ying, and Kathryn Ellis were the top three researchers. The top three cited journals were Neurology, Alzheimers & Dementia, and Journal of Alzheimer's Disease. The keywords clustering were "depression", "functional connectivity", "cognitive reserve", "cognitive function", "physical activity", "recommendations", "dementia prevention", " behavioral disorders", "primary care", "early diagnosis", and "community-based study". Keywords with the highest citation bursts include "physical activity", "framework", "preclinical Alzheimer's disease", "future dementia", and "late life depression".

Conclusions

Parallel to the growth trend, the range of research scopes and topics is expanding steadily, focusing on early screening and prevention, negative emotion, and symptom management, broadening researchers' perspectives, which can provide reference and guidance for nursing researchers to conduct research.

The effects of olive oil consumption on cognitive performance: a systematic review

Introduction

The Mediterranean diet is marked by the regular intake of olive oil, which may play a role in preventing and protecting against cognitive deterioration and dementia. The strength of these effects have been examined by several recent randomized controlled trials (RCTs), but their findings have not been consistent. In light of this inconsistency, the present study performed a systematic review to examine the relationship between the consumption of olive oil and cognition.

Methods

The Web of Science, Scopus, PubMed, and Google Scholar were systematically searched up to August 11, 2023. The review included RCTs, cross-sectional studies, cohort studies and case-control studies that explored the impact of olive oil consumption on cognitive performance among those older than 55 years old. Studies were excluded if they employed a design other than those mentioned above, involved participants under 55 years old, or did not specifically examine the cognitive effects of olive oil consumption. The quality of the included studies were measured using the Cochrane risk-of-bias tool and the Newcastle Ottawa Scale checklists.

Results

Eleven studies were identified, which were comprised of four cross-sectional studies, four prospective cohort studies and three RCTs. The cohort studies and RCTs consistently found that olive oil consumption had a favorable effect on cognitive performance across a number of cognitive domains over time. Similarly, all of the cross-sectional studies reported that the consumption of olive oil was positively associated with cognitive health.

Conclusion

The consumption of olive oil was found to enhance cognitive functioning and to reduce cognitive decline. Further large-scale investigations are required to strengthen this conclusion.

Cognitive and biological effects of citrus phytochemicals in subjective cognitive decline: a 36-week, randomized, placebo-controlled trial

Background

Auraptene (AUR) and naringenin (NAR) are citrus-derived phytochemicals that influence several biological mechanisms associated with cognitive decline, including neuronal damage, oxidative stress and inflammation. Clinical evidence of the efficacy of a nutraceutical with the potential to enhance cognitive function in cohorts at risk of cognitive decline would be of great value from a preventive perspective. The primary aim of this study is to determine the cognitive effects of a 36-week treatment with citrus peel extract standardized in levels of AUR and NAR in older adults experiencing subjective cognitive decline (SCD). The secondary aim is to determine the effects of these phytochemicals on blood-based biomarkers indicative of neuronal damage, oxidative stress, and inflammation.

Methods

Eighty older persons with SCD will be recruited and randomly assigned to receive the active treatment (400 mg of citrus peel extract containing 0.1 mg of AUR and 3 mg of NAR) or the placebo at a 1:1 ratio for 36 weeks. The primary endpoint is a change in the Repeatable Battery for the Assessment of Neuropsychological Status score from baseline to weeks 18 and 36. Other cognitive outcomes will include changes in verbal and nonverbal memory, attention, executive and visuospatial functions. Blood samples will be collected from a consecutive subsample of 60 participants. The secondary endpoint is a change in interleukin-8 levels over the 36-week period. Other biological outcomes include changes in markers of neuronal damage, oxidative stress, and pro- and anti-inflammatory cytokines.

Conclusion

This study will evaluate whether an intervention with citrus peel extract standardized in levels of AUR and NAR has cognitive and biological effects in older adults with SCD, facilitating the establishment of nutrition intervention in people at risk of cognitive decline.

Trial registration

The trial is registered with the United States National Library of Medicine at the National Institutes of Health Registry of Clinical Trials under the code NCT04744922 on February 9^th, 2021 (https://www.clinicaltrials.gov/ct2/show/NCT04744922).

Artificial Cognitive Systems Applied in Executive Function Stimulation and Rehabilitation Programs: A Systematic Review

This article presents a systematic review of studies on cognitive training programs based on artificial cognitive systems and digital technologies and their effect on executive functions. The aim has been to identify which populations have been studied, the characteristics of the implemented programs, the types of implemented cognitive systems and digital technologies, the evaluated executive functions, and the key findings of these studies. The review has been carried out following the PRISMA protocol; five databases have been selected from which 1889 records were extracted. The articles were filtered following established criteria, to give a final selection of 264 articles that have been used for the purposes of this study in the analysis phase. The findings showed that the most studied populations were school-age children and the elderly. The most studied executive functions were working memory and attentional processes, followed by inhibitory control and processing speed. Many programs were commercial, customizable, gamified, and based on classic tasks. Some more recent initiatives have begun to incorporate user-machine interfaces, robotics, and virtual reality, although studies on their effects remain scarce. The studies recognize multiple benefits of computerized neuropsychological stimulation and rehabilitation programs for executive functions in different age groups, but there is a lack of studies in specific population sectors and with more rigorous research designs.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13369-022-07292-5.

Adherence to a Mediterranean Diet Pattern, Physical Activity, and Physical Self-Concept in Spanish Older Adults

Background: The aging world population is accelerating rapidly. Physical self-concept (PSC) is one of the psychosocial factors with the greatest influence on an individual’s well-being and health. The traditional Mediterranean dietary pattern (MDP) is considered one of the healthiest dietary models, as it is nutritionally complete and easy to follow. Objective: To assess the adherence to MDP and its association with the practice of physical activity (PA) and PSC levels in the older adult Spanish population. Methods: A cross-sectional study was conducted on a representative sample of Spanish older adults (n = 342; older than 55 years old). Their PSC was assessed using a previously validated PSC questionnaire. Adherence to an MDP was assessed using a validated Mediterranean Diet Adherence Screener questionnaire. Their PA was measured using the Spanish version of the Rapid Assessment of Physical Activity Questionnaire. Data on age, sex, hypertension, cholesterol or diabetes suffered in the last 12 months, as well as weight, height, and BMI, were collected. Results: At the lowest levels of PSC, the percentage of individuals who were non-active and non-adhering to the MDP was lower compared to the highest levels (75.0% vs. 19.6; p = 0.001; Cramer’s V = 0.414, and 83.3% vs. 57.9%; p = 0.001; Cramer’s V = 0.221, respectively). This sample showed an abandonment of the most classic habits of the MDP, such as the consumption of olive oil, vegetables, fruits, nuts and fish. Conclusions: Non-adherence to the MDP and low levels of PA are associated with low levels of PSC in older adults.

The Effect of Mediterranean Diet on Cognitive Functions in the Elderly Population

At present, due to the demographic changes and the rise of senior population worldwide, there is effort to prolong an active life of these people by both pharmacological and non-pharmacological strategies. The purpose of this article is, on the basis of the literature review of recent clinical studies, to discuss one of such strategy, i.e., the effect of Mediterranean Diet (MedDiet) on the cognitive functions among both the cognitively unimpaired and impaired elderly people. The methodology includes a literature review of full-text, peer-reviewed journal studies written in English and published in Web of Science and PubMed between 1 January 2016 and 28 February 2021. The findings indicate that the adherence to MedDiet has a positive effect on both cognitively impaired and unimpaired older population, especially on their memory, both in the short and long run. The results show that the higher adherence to MedDiet proves to have a better effect on global cognitive performance of older people. In addition, the adherence to MedDiet offers other benefits to older people, such as reduction of depressive symptoms, lowered frailty, as well as reduced length of hospital stays.