Subjective memory complaints in young people; their relationship withobjective cognitive performance and the role of neuroticism / Quejas subjetivas de memoria en jóvenes; su relación con el rendimiento cognitivo objetivo y el papel del neuroticismo

Las percepciones de olvidos recurrentes o episodios de distracción en la vida diaria se denominan quejas subjetivas de memoria (QSM). Su naturaleza se ha estudiado ampliamente en adultos mayores, pero su importancia y relación con el rendimiento neurocognitivo no se han abordado por completo en adultos más jóvenes. Se han sugerido algunos rasgos psicológicos como posibles moderadores de la asociación entre el rendimiento de la memoria objetiva y subjetiva. El primer objetivo de este estudio fue analizar la correspondencia entre la percepción objetiva y subjetiva de los fallos de memoria en jóvenes. En segundo lugar, estudiamos si el rasgo psicológico del neuroticismo podría estar influyendo en esta relación. Para ello, medimos QSM, diferentes dominios cognitivos (memoria episódica y de trabajo y funciones ejecutivas) y neuroticismo en 80 hombres y mujeres jóvenes. Los resultados mostraron que solo la memoria episódica inmediata estaba estadísticamente relacionada con los QSM. Curiosamente, las relaciones negativas entre el rendimiento de la memoria objetiva y subjetiva solo aparecieron en participantes con mayor neuroticismo. Por lo tanto, las quejas de memoria reportadas por los jóvenes podrían reflejar un peor rendimiento de la memoria episódica inmediata, mientras que el neuroticismo jugaría un papel principal en la asociación entre los déficits de memoria y las QSM. Este estudio proporciona datos que pueden ayudar a comprender mejor las QSM en los jóvenes.(AU)

Perceptions of recurrent forgetfulness or episodes of distraction in daily life are referred to as subjective memory complaints (SMCs). Their nature has been extensively studied in older adults, but their significance and relationship with neurocognitive performance have not been fully ad-dressed in younger adults. Some psychological traits have been suggested as possible moderators of the association between objective and subjective memory performance. The first aim of this study was to analyze the corre-spondence between the objective and subjective perception of memory failures in young people. Second, we studied whether the psychological trait of neuroticism could be influencing this relationship. Todo this, we measured SMCs, different cognitive domains (episodic and working memory and executive functions), and neuroticism in 80 young men and women. Results showed that only immediate episodic memory was statisti-cally related to SMCs. Interestingly, the negative relationships between ob-jective and subjective memory performance only appeared in participants with higher neuroticism. Thus, memory complaints reported by young people could reflect poorer immediate episodic memory performance, whereas neuroticism would play a main role in the association between memory deficits and SMCs. This study provides data that can help to bet-ter understand SMCs in young people.(AU)

Individual posterior alpha rhythms and cognitive reserve as possible early prognostic markers in people with subjective memory complaints.

Subjective memory complaints (SMCs) are a memory disorder that often precedes mild cognitive impairment (MCI) or Alzheimer's disease (AD). Both individual alpha rhythms and cognitive reserve (CR) represent key features of SMCs and provide useful tools to characterize and predict the course of the disorder. We studied whether older people with SMCs may also present some abnormal resting state electroencephalogram (rsEEG) alpha rhythms, and whether alpha rhythms are associated with CR. To do this, eyes-closed rsEEG were recorded in 68 older people with and without SMCs. The individual alpha indexes alpha/theta transition frequency (TF) and individual alpha frequency peak (IAFp) were computed. TF and IAFp were also used to determine the alpha1, alpha2, and alpha3 power frequency. Results indicated no differences in TF or IAFp between older people with SMCs and controls. The SMCs group showed a reduction in alpha3 power in comparison with controls. Specifically, women with SMCs were characterized by a significant decrease in alpha3 power compared to control women. Furthermore, only in SMCs group, greater CR was associated with slow IAFp. In sum, these results suggest that TF and IAFp are two stable indexes that are not influenced by the presence of SMCs. However, the reduction in alpha3, as observed in women with SMCs, shows an abnormal posterior rsEEG at alpha power. Finally, the compensatory mechanisms of CR appear to interact with the neurophysiological mechanisms that underlie the regulation of alpha rhythms.

Clusters of cognitive performance predict long-term cognitive impairment in elderly patients with subjective memory complaints and healthy controls.

INTRODUCTION: Patients with subjective memory complaints (SMC) may include subgroups with different neuropsychological profiles and risks of cognitive impairment. METHODS: Cluster analysis was performed on two datasets (n: 630 and 734) comprising demographic and neuropsychological data from SMC and healthy controls (HC). Survival analyses were conducted on clusters. Bayesian model averaging assessed the predictive utility of clusters and other biomarkers. RESULTS: Two clusters with higher and lower than average cognitive performance were detected in SMC and HC. Assignment to the lower performance cluster increased the risk of cognitive impairment in both datasets (hazard ratios: 1.78 and 2.96; Plog-rank: 0.04 and <0.001) and was associated with lower hippocampal volumes and higher tau/amyloid beta 42 ratios in cerebrospinal fluid. The effect of SMC was small and confounded by mood. DISCUSSION: This study provides evidence of the presence of cognitive clusters that hold biological significance and predictive value for cognitive decline in SMC and HC. HIGHLIGHTS: Patients with subjective memory complaints include two cognitive clusters. Assignment to the lower performance cluster increases risk of cognitive impairment. This cluster shows a pattern of biomarkers consistent with incipient Alzheimer's disease pathology. The same cognitive cluster structure is found in healthy controls. The effect of memory complaints on risk of cognitive decline is small and confounded.

Fish and Shellfish Consumption, Cognitive Health and Mortality from Alzheimer's Disease among US Adults Aged 60 and Older.

BACKGROUND: Relationships of fish-shellfish consumption, cognitive health and mortality from Alzheimer's disease (AD) among US adults aged 60 years and older have not been adequately studied. OBJECTIVES: To determine the relationship of fish-shellfish consumption, cognitive health and mortality from AD in US adults aged 60 years and older. DESIGN, SETTING AND PARTICIPANTS: The data of this cross-sectional study of US adults aged 60 years and older were from the National Nutrition and Health Examination Survey (NHANES) datasets. Frequency of fish-shellfish consumption, its association with subjective cognitive decline (SCD) and AD mortality of these participants between 1999 and 2018 and cognitive assessment scores between 2011 and 2014 were analyzed. MEASUREMENTS AND RESULTS: US adults aged 60 years and older consumed fish-shellfish 1.2 times/week and had a blood Hg of 1.63 ug/L on average between 1999 and 2018. Participants aged 60 years and older in the highest quartile of fish-shellfish consumption (~3 times/week) had significantly higher cognitive assessment scores than those in the lowest quartile (rare or no fish-shellfish consumption). Adults in the highest quartile of fish-shellfish consumption had a 30% lower risk (odds ratio 0.7, 95%CI 0.57-0.87) of SCD, and 44% lower risk (hazard ratio 0.56, 95%CI 0.35-0.9) of AD mortality than those in the lowest quartile. CONCLUSION: Increased fish-shellfish consumption was associated with improved scores of cognitive assessment and reduced risks of SCD and AD mortality.

News event memory in amnestic and non-amnestic MCI, heritable risk for dementia, and subjective memory complaints.

Robust and sensitive clinical measures are needed for more accurate and earlier detection of Alzheimer's disease (AD), for staging preclinical AD, and for gauging the efficacy of treatments. Mild impairment on episodic memory tests is thought to indicate a cognitive risk of developing AD and mild cognitive impairment (MCI), considered to be a transitional stage between normal aging and AD. Novel tests of semantic memory, such as memory for news events, are also impaired early on but have received little clinical attention even though they may provide a novel way to assess cognitive risk for AD. We examined memory for news events in older adults with normal cognition (NC, N = 34), amnestic MCI (aMCI, N = 27), or non-aMCI (N = 10) using the Retrograde Memory News Events Test (RM-NET). We asked if news event memory was sensitive to 1) aMCI and also non-aMCI, which has rarely been examined, 2) genetic risk for dementia (positive family history of any type of dementia, presence of an APOE-4 allele, or polygenic risk for AD), and 3) subjective memory functioning judgments about the past. We found that both MCI subgroups exhibited impaired RM-NET Lifespan accuracy scores together with temporally-limited retrograde amnesia. For the aMCI group amnesia extended back 45 years prior to testing, but not beyond that time frame. The extent of retrograde amnesia could not be reliably estimated in the small non-aMCI group. The effect sizes of having MCI on the RM-NET were medium for the non-aMCI group and large for the aMCI group, whereas the effect sizes of participant characteristics on RM-NET accuracy scores were small. For the combined MCI group (N = 37), news event memory was significantly related to positive family history of dementia but was not related to the more specific genetic markers of AD risk. For the NC group, news event memory was not related to any measure of genetic risk. Objective measures of past memory from the RM-NET were not related to subjective memory judgements about the present or the recent past in either group. By contrast, when individuals subjectively compared their present versus past memory abilities, there was a significant association between this judgment and objective measures of the past from the RM-NET (direct association for the NC group and inverse for the MCI group). The RM-NET holds significant promise for early identification of those with cognitive and genetic risk factors for AD and non-AD dementias.

White Matter Microstructure Analysis in Subjective Memory Complaints and Cognitive Impairment: Insights from Diffusion Kurtosis Imaging and Free-Water DTI.

Background: Dementia is characterized by a cognitive decline in memory and other domains that lead to functional impairments. As people age, subjective memory complaints (SMC) become common, where individuals perceive cognitive decline without objective deficits on assessments. SMC can be an early sign and may precede amnestic mild cognitive impairment (MCI), which frequently advances to Alzheimer's disease (AD). Objective: This study aims to investigate white matter microstructure in individuals with SMC, in cognitively impaired (CI) cohorts, and in cognitively normal individuals using diffusion kurtosis imaging (DKI) and free water imaging (FWI). The study also explores voxel-based correlations between DKI/FWI metrics and cognitive scores to understand the relationship between brain microstructure and cognitive function. Methods: Twelve healthy controls (HCs), ten individuals with SMC, and eleven CI individuals (MCI or AD) were enrolled in this study. All participants underwent MRI 3T scan and the BNI Screen (BNIS) for Higher Cerebral Functions. Results: The mean kurtosis tensor and anisotropy of the kurtosis tensor showed significant differences across the three groups, indicating altered white matter microstructure in CI and SMC individuals. The free water volume fraction (f) also revealed group differences, suggesting changes in extracellular water content. Notably, these metrics effectively discriminated between the CI and HC/SMC groups. Additionally, correlations between imaging metrics and BNIS scores were found for CI and SMC groups. Conclusions: These imaging metrics hold promise in discriminating between individuals with CI and SMC. The observed differences indicate their potential as sensitive and specific biomarkers for early detection and differentiation of cognitive decline.

Regional covariance of white matter hyperintensity volume patterns associated with hippocampal volume in healthy aging.

Hippocampal volume is particularly sensitive to the accumulation of total brain white matter hyperintensity volume (WMH) in aging, but how the regional distribution of WMH volume differentially impacts the hippocampus has been less studied. In a cohort of 194 healthy older adults ages 50-89, we used a multivariate statistical method, the Scaled Subprofile Model (SSM), to (1) identify patterns of regional WMH differences related to left and right hippocampal volumes, (2) examine associations between the multimodal neuroimaging covariance patterns and demographic characteristics, and (3) investigate the relation of the patterns to subjective and objective memory in healthy aging. We established network covariance patterns of regional WMH volume differences associated with greater left and right hippocampal volumes, which were characterized by reductions in left temporal and right parietal WMH volumes and relative increases in bilateral occipital WMH volumes. Additionally, we observed lower expression of these hippocampal-related regional WMH patterns were significantly associated with increasing age and greater subjective memory complaints, but not objective memory performance in this healthy older adult cohort. Our findings indicate that, in cognitively healthy older adults, left and right hippocampal volume reductions were associated with differences in the regional distribution of WMH volumes, which were exacerbated by advancing age and related to greater subjective memory complaints. Multivariate network analyses, like SSM, may help elucidate important early effects of regional WMH volume on brain and cognitive aging in healthy older adults.

Subjective memory complaints and medication adherence among hypertensive Korean older adults with multimorbidity: mediating effect of depression and social support.

BACKGROUND & AIM(S): Medication adherence (MA) is a key factor in maintaining adequate blood pressure and preventing complications. However, some older adults experience difficulties in taking medicine properly due to declines in cognitive function. Although subjective memory complaints (SMC) are recognized as early markers of cognitive impairment, previous studies concerning the relationship between MA and cognitive function have focused only on objective cognitive function. Furthermore, while depression has a high correlation with SMC, low MA, and social support, there is limited evidence on their relationship. This study aims to understand the effect of SMC on MA and the mediating effect of depression and social support. METHOD(S): This study is a descriptive cross-sectional investigation. A sample of 195 community-dwelling hypertensive older adults with multimorbidity from 3 community senior centers in Gwangju, South Korea were recruited through convenience sampling. Data was collected through face-to-face survey from January to March 2018. The PROCESS macro v4.2 program [Model 6] was used to analyze the mediating effect of depression and social support in the relationship between SMC and MA. Data analysis was performed using SPSS/WIN 26.0 and STATA MP 17.0. RESULTS: The average MA was 6.74. There were significant differences in MA according to awareness of prescribed drugs, awareness of side effects, insomnia, and healthcare accessibility. SMC was positively correlated with depression, while social support and MA were negatively correlated. While depression was a significant mediator of the effect of SMC on MA, the mediating effect of social support was not significant. The multiple mediation effect of depression and social support was not significant. CONCLUSION: The results suggest that medication management of older adults in community settings should be accompanied by a comprehensive health assessment of associated factors. Health professionals should explore strategies to improve memory as well as prevent and alleviate depression to increase MA among hypertensive older adults with multimorbidity.

Association of mobile device proficiency and subjective cognitive complaints with financial management ability among community-dwelling older adults: a population-based cross-sectional study.

BACKGROUND: Mobile devices have been used by many older adults and have the potential to assist individuals with subjective cognitive complaints (SCCs) in daily living tasks. Financial management is one of the most complex daily activity for older adults, as it is easily impaired in the prodromal stage of dementia and cognitive impairment. AIM: To investigate financial management ability among older adults from SCCs and mobile device proficiency. METHODS: A self-administered questionnaire was sent to 529 participants who were ≥ 65 years and regularly use mobile devices. Participants were divided into four groups based on SCC prevalence and scores of the Mobile Device Proficiency Questionnaire (MDPQ-16). Financial management abilities were compared between groups using the Process Analysis of Daily Activities for Dementia subscale. Regression model and crosstabulation table were used to investigate associations in detail. RESULTS: A significant difference in financial management ability was observed among the four groups (p < 0.001), with the dual impairment group showed significantly lower than the robust and SCC groups (p < 0.001). Educational history, sex, and MDPQ-16 score were significantly associated with participants' financial management ability (p ≤ 0.01). The proportion of participants who could use ATMs and electronic money independently was significantly lower among those with low proficiency in mobile devices (LPM), regardless of SCC (p < 0.05). CONCLUSION: The LPM group showed an impaired ability to manage their finances, particularly in situations where they would use information devices. Therefore, healthcare professionals should assess not only the SCC but also their proficiency with mobile devices to predict their impairment in activities of daily living.

Prevalencia de quejas subjetivas de memoria: estudio poblacional en España / Prevalence of subjective memory complaints: Population study in Spain

Introducción Las quejas subjetivas de memoria (QSM) pueden ser una señal inicial de un posterior deterioro de las funciones cognitivas. Sin embargo, no se han publicado estudios poblacionales cubriendo toda España para conocer la prevalencia de las QSM. El objetivo del presente estudio fue conocer la prevalencia de las QSM en la población general residente en España >50 años y, también qué actuaciones se llevaban a cabo al respecto. Materiales y métodos Se realizaron entrevistas mediante un cuestionario online/Computer Assisted Web Interview (CAWI) a una muestra representativa a nivel nacional >50 años. La encuesta constaba de 34 ítems divididos en 2 bloques. Se consideró presencia de QSM cuando en la pregunta 1 el sujeto contestaba que ‘Sí’ tenía algún problema de memoria. Resultados Se entrevistó a 2.300 personas (53,7% mujeres; 23,9% ≥75 años). El 31% contestaron que consideraban que tenían un problema de memoria (sin diferencias entre sexos, media de tiempo con problemas de memoria de 3,0 años). Se observó mayor prevalencia de QSM en ≥75 años (44%). El 90% no incluían ningún alimento específico en su dieta para sus problemas de memoria, y tampoco estaban tomando productos farmacéuticos, complementos de la dieta o suplementos nutricionales (92%). El 78% de los entrevistados con QSM no han consultado a profesionales sanitarios por sus problemas de memoria. Conclusiones Las QSM tienen una prevalencia considerable en nuestro medio, afectando a casi un tercio de los individuos >50 años. La mayoría de los entrevistados con quejas de memoria no buscó el consejo/recomendación de profesionales sanitarios con respecto a las mismas. (AU)

Introduction Subjective memory complaints (SMC) might be an early sign of further deterioration in cognitive functions. However, no population studies have been published covering all Spain to determine the SMC prevalence. The objective of the present study was to determine the SMC prevalence in the general population residing in Spain >50 years of age and also which related actions were done. Materials and methods Interviews were conducted with a nationally representative sample >50 years of age using an online/computer assisted web interview (CAWI) questionnaire. The survey consisted of 34 items divided into two blocks. Presence of SMC was considered when in question 1 the subject answered that “Yes” he had some memory problem. Results Two thousand three hundred people (53.7% women; 23.9% ≥75 years old) were interviewed. 31% answered that they considered they had a memory problem (no differences between sexes, mean time with memory problems of 3.0 years). A higher prevalence of SMC was observed in ≥75 years old (44%). 90% did not include any specific foods in their diet for their memory problems, neither were taking any pharmaceuticals, diet supplements or nutritional supplements (92%). 78% of those interviewed with SMC have not consulted health professionals for their memory problems. Conclusions SMC are considerably prevalent in our environment affecting almost a third of people ≥50 years of age. Most of the interviewees with SMC did not go to health professionals to manage their SMC. (AU)

Prevalencia de quejas subjetivas de memoria: estudio poblacional en España / Prevalence of subjective memory complaints: Population study in Spain

Introducción Las quejas subjetivas de memoria (QSM) pueden ser una señal inicial de un posterior deterioro de las funciones cognitivas. Sin embargo, no se han publicado estudios poblacionales cubriendo toda España para conocer la prevalencia de las QSM. El objetivo del presente estudio fue conocer la prevalencia de las QSM en la población general residente en España >50 años y, también qué actuaciones se llevaban a cabo al respecto. Materiales y métodos Se realizaron entrevistas mediante un cuestionario online/Computer Assisted Web Interview (CAWI) a una muestra representativa a nivel nacional >50 años. La encuesta constaba de 34 ítems divididos en 2 bloques. Se consideró presencia de QSM cuando en la pregunta 1 el sujeto contestaba que ‘Sí’ tenía algún problema de memoria. Resultados Se entrevistó a 2.300 personas (53,7% mujeres; 23,9% ≥75 años). El 31% contestaron que consideraban que tenían un problema de memoria (sin diferencias entre sexos, media de tiempo con problemas de memoria de 3,0 años). Se observó mayor prevalencia de QSM en ≥75 años (44%). El 90% no incluían ningún alimento específico en su dieta para sus problemas de memoria, y tampoco estaban tomando productos farmacéuticos, complementos de la dieta o suplementos nutricionales (92%). El 78% de los entrevistados con QSM no han consultado a profesionales sanitarios por sus problemas de memoria. Conclusiones Las QSM tienen una prevalencia considerable en nuestro medio, afectando a casi un tercio de los individuos >50 años. La mayoría de los entrevistados con quejas de memoria no buscó el consejo/recomendación de profesionales sanitarios con respecto a las mismas. (AU)

Introduction Subjective memory complaints (SMC) might be an early sign of further deterioration in cognitive functions. However, no population studies have been published covering all Spain to determine the SMC prevalence. The objective of the present study was to determine the SMC prevalence in the general population residing in Spain >50 years of age and also which related actions were done. Materials and methods Interviews were conducted with a nationally representative sample >50 years of age using an online/computer assisted web interview (CAWI) questionnaire. The survey consisted of 34 items divided into two blocks. Presence of SMC was considered when in question 1 the subject answered that “Yes” he had some memory problem. Results Two thousand three hundred people (53.7% women; 23.9% ≥75 years old) were interviewed. 31% answered that they considered they had a memory problem (no differences between sexes, mean time with memory problems of 3.0 years). A higher prevalence of SMC was observed in ≥75 years old (44%). 90% did not include any specific foods in their diet for their memory problems, neither were taking any pharmaceuticals, diet supplements or nutritional supplements (92%). 78% of those interviewed with SMC have not consulted health professionals for their memory problems. Conclusions SMC are considerably prevalent in our environment affecting almost a third of people ≥50 years of age. Most of the interviewees with SMC did not go to health professionals to manage their SMC. (AU)

Degeneration of the cholinergic system in individuals with subjective cognitive decline: A systematic review.

BACKGROUND: Subjective cognitive decline (SCD) is a risk factor for future cognitive impairment and dementia. It is uncertain whether the neurodegeneration of the cholinergic system is already present in SCD individuals. We aimed to review the current evidence about the association between SCD and biomarkers of degeneration in the cholinergic system. METHOD: Original articles were extracted from three databases: Pubmed, Web of Sciences, and Scopus, in January 2023. Two researchers screened the studies independently. RESULTS: A total of 11 research articles were selected. SCD was mostly based on amnestic cognitive complaints. Cholinergic system biomarkers included neuroimaging markers of basal forebrain volume, functional connectivity, transcranial magnetic stimulation, or biofluid. The evidence showed associations between basal forebrain atrophy, poorer connectivity of the cholinergic system, and SCD CONCLUSIONS: Degenerative changes in the cholinergic system can be present in SCD. Subjective complaints may help when identifying individuals with brain changes that are associated with cognitive impairment. These findings may have important implications in targeting individuals that may benefit from cholinergic-target treatments at very early stages of neurodegenerative diseases.

FACEmemory®, an Innovative Online Platform for Episodic Memory Pre-Screening: Findings from the First 3,000 Participants.

BACKGROUND: The FACEmemory® online platform comprises a complex memory test and sociodemographic, medical, and family questions. This is the first study of a completely self-administered memory test with voice recognition, pre-tested in a memory clinic, sensitive to Alzheimer's disease, using information and communication technologies, and offered freely worldwide. OBJECTIVE: To investigate the demographic and clinical variables associated with the total FACEmemory score, and to identify distinct patterns of memory performance on FACEmemory. METHODS: Data from the first 3,000 subjects who completed the FACEmemory test were analyzed. Descriptive analyses were applied to demographic, FACEmemory, and medical and family variables; t-test and chi-square analyses were used to compare participants with preserved versus impaired performance on FACEmemory (cut-off = 32); multiple linear regression was used to identify variables that modulate FACEmemory performance; and machine learning techniques were applied to identify different memory patterns. RESULTS: Participants had a mean age of 50.57 years and 13.65 years of schooling; 64.07% were women, and 82.10% reported memory complaints with worries. The group with impaired FACEmemory performance (20.40%) was older, had less schooling, and had a higher prevalence of hypertension, diabetes, dyslipidemia, and family history of neurodegenerative disease than the group with preserved performance. Age, schooling, sex, country, and completion of the medical and family history questionnaire were associated with the FACEmemory score. Finally, machine learning techniques identified four patterns of FACEmemory performance: normal, dysexecutive, storage, and completely impaired. CONCLUSIONS: FACEmemory is a promising tool for assessing memory in people with subjective memory complaints and for raising awareness about cognitive decline in the community.

[Prevalence of subjective memory complaints: Population study in Spain]. / Prevalencia de quejas subjetivas de memoria: estudio poblacional en España.

INTRODUCTION: Subjective memory complaints (SMC) might be an early sign of further deterioration in cognitive functions. However, no population studies have been published covering all Spain to determine the SMC prevalence. The objective of the present study was to determine the SMC prevalence in the general population residing in Spain >50 years of age and also which related actions were done. MATERIALS AND METHODS: Interviews were conducted with a nationally representative sample >50 years of age using an online/computer assisted web interview (CAWI) questionnaire. The survey consisted of 34 items divided into two blocks. Presence of SMC was considered when in question 1 the subject answered that "Yes" he had some memory problem. RESULTS: Two thousand three hundred people (53.7% women; 23.9% ≥75 years old) were interviewed. 31% answered that they considered they had a memory problem (no differences between sexes, mean time with memory problems of 3.0 years). A higher prevalence of SMC was observed in ≥75 years old (44%). 90% did not include any specific foods in their diet for their memory problems, neither were taking any pharmaceuticals, diet supplements or nutritional supplements (92%). 78% of those interviewed with SMC have not consulted health professionals for their memory problems. CONCLUSIONS: SMC are considerably prevalent in our environment affecting almost a third of people ≥50 years of age. Most of the interviewees with SMC did not go to health professionals to manage their SMC.

The MN RIDE pilot: feasibility of a synchronous, remotely delivered, aerobic exercise training program for rural-dwelling adults with subjective cognitive decline.

INTRODUCTION: Out of all the modifiable risk factors for Alzheimer's disease and related dementias (ADRD), physical inactivity is the strongest. Rural residents have an increased risk for dementia and face significant barriers to accessing ADRD information, caregiving support, and memory-related services, which contributes to substandard care. Rural communities have greater barriers to participating in physical activity, and in particular exercise, due to lack of social support, travel/weather problems, and lack of facilities/equipment. The purpose of this pilot study was to implement and evaluate the feasibility and safety of a synchronous, remotely delivered, aerobic exercise (AEx) telerehabilitation program in persons with subjective cognitive decline (SCD) living in rural areas. METHODS: The Minnesota Rehabilitation Intervention for Dementia Evasion for rural residents (MN RIDE) pilot study was one of five pilot studies conducted through the Center for Community Engaged Rural Dementia and Alzheimer's Research, conducted in collaboration with the Memory Keepers Medical Discovery Team. The Memory Keepers Medical Discovery Team employs a community-based participatory research model and uses a community advisory group, community-based researchers and a rural community engagement specialist to ensure research studies are aligned with rural community needs and to facilitate the recruitment of participants living in rural northern Minnesota. The MN RIDE study employed a single group, pretest-post-test design to test the feasibility and safety of an AEx-focused synchronous telerehabilitation program in rural-living middle-aged or older adults (>45 years) with SCD (indicated by answering yes to both, 'Do you perceive memory or cognitive difficulties?' and 'In the last two years, has your cognition or memory declined?'). All 36 AEx sessions (conducted over 12 weeks) were supervised remotely via smart devices and Zoom. The AEx program was classified as moderate intensity stationary cycling starting at a rating of perceived exertion (RPE) 11-12 or for 30-35 minutes in session 1, and was alternatively increased by 1-point RPE or 5-minute increments as tolerated up to RPE 12-14 for 50 minutes a session over time (by session 18). Secondarily, moderate intensity was defined as achieving an exercise heart rate of 64-76% of age-predicted maximum heart rate (HRmax). Feasibility and safety outcomes were assessed by session attendance, intensity adherence, presence of adverse events, and participant satisfaction. RESULTS: The average age of the study sample (n=9) was 57.44±7.16 years (average age of SCD onset 53.44±7.47 years) with 14.00±5.57 years of education and 88.9% female. All patients completed the study, resulting in a dropout rate of 0%. Out of the possible 324 sessions scheduled, 276 were attended (85% session adherence). Average intensity metrics achieved over the AEx sessions were RPE 13.2±0.5 and HRmax 72.0±7.9%, which both represent of moderate intensity AEx metrics. No adverse events were reported. CONCLUSION: This pilot study further provides the first evidence of preliminary feasibility of synchronous audiovisual, telerehabilitation programs delivered to rural residents at risk for ADRD. Thus, exercise telerehabilitation programs that focus on AEx could be viable and useful tools to overcome situations with limited access to healthcare services such as in rural communities. Further controlled studies with greater sample size could help further expand our results.

Subjective memory complaints: Prevalence, associated factors and sex differences in the ELSI-Brazil study.

BACKGROUND: Subjective memory complaints (SMCs) are a possible prodrome of cognitive decline but are understudied in low- and middle-income countries (LMIC). We aimed to estimate the prevalence of SMCs in a large, nationally representative sample of older adults from Brazil and to identify sociodemographic and health-related factors that are associated with SMCs independently of objective memory. METHODS: Baseline data (n = 7831) from the ELSI-Brazil study, a national representative sample of adults aged 50 and over. They were asked to rate their memory and then divided into two groups - having or not having SMCs. Logistic regression models were used to estimate the association of demographic characteristics, health related factors, objective memory performance and disability in basic (b-ADL), instrumental (i-ADL), and advanced (a-ADL) activities of daily living associated with SMCs. Whether sex was an effect modifier of the association between age and objective memory performance and SMCs was also tested. RESULTS: Of the sample, 42% (95% CI; 39.9-43.9) had SMCs, and it was higher among women (46.9%) than men (35.9%). SMC prevalence decreased with age among women and increased among men, and for both it decreased with better cognitive performance. Fully adjusted logistic regression model showed that older age, higher education, higher b-ADL scores, and better cognitive performance were associated with decreased SMCs, while being female, with higher number of chronic conditions, higher i-ADL scores, worst self-rated health, and an increased number of depressive symptoms were associated with increased SMCs. However, the interaction test (p < 0.001) confirmed that increased age was associated with decreased SMCs only among women, and that better objective memory performance was associated with decreased SMCs only among men. CONCLUSIONS: SMCs are common in the Brazilian older population and are associated with health and sociodemographic factors, with different patterns between men and women. There is a need for future studies looking at the cognitive trajectory and dementia risk in older adults with subjective cognitive complaints.

Sarcopenia Screened with SARC-F and Subjective Memory Complaints Are Independently Associated with Increased Risk of Incident Dementia among Cognitively Unimpaired Older Adults.

OBJECTIVES: The main aim of this study was to examine the association of sarcopenia and subjective memory complaints with the incidence of dementia in a population-based cohort of cognitively unimpaired older adults. DESIGN: Three-year longitudinal study. SETTINGS AND PARTICIPANTS: A total of 2163 community-dwelling persons aged 65 years or older who participated in the National Health Interview Survey in Taiwan, 2017. MEASUREMENTS: Sarcopenia was determined based on SARC-F, a self-reported symptom-based questionnaire that includes five components: strength, assistance walking, rise from a chair, climb stairs, and falls. Two questions ("Do you have difficulties with your memory or attention?" and "Do you have difficulties with your memory only or attention only or both?") were used to screen for subjective memory complaints (SMCs). The incidence of dementia was determined by data linkage to the Taiwan National Health Insurance claims database from 2018 to 2020. RESULTS: Among the 2163 participants without dementia at baseline, 135 had incident dementia during the 3-year follow-up, giving a crude incidence rate of 6.2% (135/2163). Compared to participants free from sarcopenia and SMCs, the adjusted hazard ratio for incident dementia was 1.83 (95% confidence interval [CI]: 1.23-2.72) for SMCs alone, 2.40 (95% CI: 1.17-4.93) for sarcopenia alone, and 2.49 (95% CI: 1.21-5.11) for coexisting SMCs and sarcopenia. CONCLUSIONS: Our results indicate that sarcopenia screened with SARC-F and SMCs independently predict the cognitively unimpaired older adults at risk of incident dementia. Our findings highlight the importance of screening not only for cognitive but also muscle deficits to identify those at increased risk of incident dementia.

Common Neuropsychiatric S ymptoms in Alzheimer's Disease, Mild Cognitive Impairment, and Subjective Memory Complaints: A Unified Framework.

The Alzheimer's disease (AD) continuum is a unique spectrum of cognitive impairment that typically involves the stages of subjective memory complaints (SMC), mild cognitive impairment (MCI), and AD dementia. Neuropsychiatric symptoms (NPS), such as apathy, anxiety, stress, and depression, are highly common throughout the AD continuum. However, there is a dearth of research on how these NPS vary across the AD continuum, especially SMC. There is also disagreement on the effects of specific NPS on each stage of the AD continuum due to their collinearity with other NPS, cognitive decline, and environmental factors (e.g., stress). In this article, we conduct a novel perspective review of the scientific literature to understand the presence of NPS across the AD continuum. Specifically, we review the effects of apathy, depression, anxiety, and stress in AD, MCI, and SMC. We then build on this knowledge by proposing two theories of NPS' occurrence across the AD continuum. Consequently, we highlight the current landscape, limitations (e.g., differing operationalization), and contentions surrounding the NPS literature. We also outline theories that could clear up contention and inspire future NPS research.

Longitudinal relationships between grip strength, subjective memory complaints and cognitive function among middle-aged and older adults in China.

BACKGROUND: Subjective memory complaints are considered an early sign of cognitive decline. Recent evidence shows that grip strength is an important predictor of cognitive function. However, few studies have compared whether one condition is uniquely associated with cognitive function when another condition is controlled for. AIMS: To explore the longitudinal associations of cognitive function with subjective memory complaints and grip strength in middle-aged and older adults, with a particular focus on whether one condition is uniquely associated with cognitive function when another condition is considered. METHODS: A total of 3,877 middle-aged and older adults (aged 45-92 years) from the China Health and Retirement Longitudinal Study reported on their demographic and health status and completed measures of grip strength and subjective memory complaints, as well as a series of cognitive tests, every two years between 2011 and 2015. Generalized estimating equation models were used to assess the relationships between grip strength, subjective memory complaints, and cognitive function. RESULTS: Grip strength was longitudinally associated with cognitive function (ß = 0.021, 95% confidence interval [CI]: 0.011, 0.030, P < 0.001) independent of subjective memory complaints. In contrast, changes in the subjective memory complaints were not related to cognitive function over time (ß = 0.107, 95% CI: - 0.025, 0.238, P = 0.112). Only at baseline subjective memory complaints were associated with poorer cognitive function (ß = - 1.142, 95% CI: - 1.309, - 0.975, P < 0.001). CONCLUSIONS: Grip strength might be a more important clinical correlate of cognitive function decline over time than subjective memory complaints. DISCUSSION: Regular assessment and close monitoring of grip strength might help identify individuals who might be at high risk for cognitive impairment.

Heterogeneity in Measures and Rates of Reported Dementia and Subjective Memory Complaints Across U.S. National Surveys.

OBJECTIVES: Several U.S. health surveillance surveys contain items related to self- and proxy reports of dementia and subjective memory complaints (SMC). Despite their similar content, these items differ in terminology, item specificity, and time frame. The goal of this study was to analyze whether item features might influence endorsement rates for dementia and SMC. METHODS: We calculated design-appropriate estimates for the endorsement of dementia and SMC across U.S.-based national surveys and employed pairwise comparisons to evaluate endorsement rates across surveys. We also examined item characteristics to explore possible effects on endorsement rates. RESULTS: Endorsement rates were wide-ranging for dementia (ranging from 2.7% to 9.9%) and SMC (5.6% to 46.6%). Pairwise comparisons revealed statistically significant differences on most dementia-related items (76%), and all SMC comparisons (100%). Items varied substantially in the terminology used to assess dementia and SMC (e.g., "dementia" vs "Alzheimer's disease") and used different time frames (e.g., "past month" vs "5 years"). DISCUSSION: National survey data on reported dementia and SMC can have important research, training, and policy implications, yet endorsement rates vary widely across surveys. That variability could emerge from subtle but influential item characteristics, and our findings highlight the need for item harmonization, in even their most basic characteristics. Standardizing items across national surveillance surveys facilitates comparison across surveys so that we can better understand the true burden of these conditions to inform public health initiatives.