Dual-task performance in old adults: cognitive, functional, psychosocial and socio-demographic variables.

BACKGROUND: Dual tasking, or the ability to executing two tasks simultaneously, has been used in recent research to predict cognitive impairments, physical frailty, and has been linked with cognitive frailty in old adults. AIM: This study aimed to determine age-related variables can predict dual-task (DT) performance in the older population. METHODS: A total of 258 healthy community-dwelling participants + 60 years were assessed in relation to their functional capacity, health, well-being, social support and years of education. Performance of a cognitive (Fluency) task and a cognitive-motor (Tracking) task was recorded under single and DT conditions. Multiple linear regression analysis was carried out for each dependent variable, in separate models including cognitive, functional and psychosocial variables. RESULTS: Performance in Fluency in DT conditions was predicted by cognitive variables, whereas performance in Tracking DT conditions was predicted by positive interaction, health status, age and motor variables. DISCUSSION: The findings suggest that a wide range of cognitive, psychological, social, physical and functional variables influence cognitive and motor performance in aging. CONCLUSION: DT methodology is sensitive to different age-related changes and could be related to frailty conditions in aging.

[Adaptation and validation of aged adults' adaptation scale to their residence (EAPAR) in Chile]. / Adaptación y validación chilena de la escala de adaptación de la persona mayor a su residencia.

BACKGROUND: The adaptation of older people to nursing homes may be problematic. Scales to assess the degree of adaptation are required. AIM: To adapt and evaluate the psychometric characteristics of the Scale of Adaptation of the Older Adults to their Residence (EAPAR) in the Chilean population. MATERIAL AND METHODS: EAPAR and self-esteem scales were applied to 106 people aged 79 ± 7 years (57% women) living in nursing homes. Reliability was measured using Cronbach's alpha. RESULTS: The instrument was adequately understood by the Chilean participants. In the content validity, the structure of the scale appears homogeneous and with an acceptable statistical significance. CONCLUSIONS: EAPAR is a reliable and valid instrument to be used by health professionals.

Changes in visual memory in mild cognitive impairment: a longitudinal study with CANTAB.

BACKGROUND: Mild cognitive impairment (MCI), as a stage in the cognitive continuum between normal ageing and dementia, is mainly characterized by memory impairment. The aims of this study were to examine CANTAB measures of temporal changes of visual memory in MCI and to evaluate the usefulness of the baseline scores for predicting changes in cognitive status. METHODS: The study included 201 participants aged over 50 years with subjective cognitive complaints. Visual memory was assessed with four CANTAB tests [paired associates learning (PAL), delayed matching to sample (DMS), pattern recognition memory (PRM) and spatial span (SSP)] administered at baseline and on two further occasions, with a follow-up interval of 18-24 months. Participants were divided into three groups according to the change in their cognitive status: participants with subjective cognitive complaints who remained stable, MCI participants who remained stable (MCI-Stable) and MCI participants whose cognitive deterioration continued (MCI-Worsened). Linear mixed models were used to model longitudinal changes, with evaluation time as a fixed variable, and multinomial regression models were used to predict changes in cognitive status. RESULTS: Isolated significant effects were obtained for age and group with all CANTAB tests used. Interactions between evaluation time and group were identified in the PAL and DMS tests, indicating different temporal patterns depending on the changes in cognitive status. Regression models also indicated that CANTAB scores were good predictors of changes in cognitive status. CONCLUSIONS: Decline in visual memory measured by PAL and DMS tests can successfully distinguish different types of MCI, and considered together PAL, DMS, PRM and SSP can predict changes in cognitive status.

Normative scores for the Timed Up & Go in a Spanish sample of community-dweller adults with preserved functionality.

Our aim was to calculate the 'Timed Up & Go' (TUG) normative scores in a Spanish sample composed of functional older adults. The TUG test provides a measure of global ambulation skills and its total score has been successfully related with functionality and other important health variables in older adults. Reliable norms are needed for adults 50 years and older that allow the early identification and intervention in motor disturbances. The study was carried out with adults from Galicia and Valencia living in the community. A total of 314 Spanish community-living participants, aged from 50 to 90 years and functionality preserved were assessed through the implementation of a cross-sectional design. Health, comorbidity, physical activity, cognitive status, functionality measures and TUG test scores were obtained. TUG scores were successfully predicted by age and gender, and significantly correlated with cognitive status and comorbidity. TUG norms were calculated by age-group for women and men. TUG normative scores were below 13s and slightly lower in men. Normative scores for women and men were lower than those proposed in studies carried-out in our context. Our norms showed risk reference scores close to those obtained by meta-analytical procedures.

Cognitive reserve and working memory in cognitive performance of adults with subjective cognitive complaints: longitudinal structural equation modeling.

OBJECTIVE: To study the influence of cognitive reserve (CR) on cognitive performance of individuals with subjective cognitive complaints (SCCs) within a period of 36 months. DESIGN: We used a general linear model repeated measures procedure to analyze the differences in performance between three assessments. We used a longitudinal structural equation modeling to analyze the relationship between CR and cognitive performance at baseline and at two follow-up assessments. SETTING: Participants with SCCs were recruited and assessed in primary care health centers. PARTICIPANTS: A total of 212 participants older than 50 years with SCCs. MEASUREMENTS: Cognitive reserve data were collected with an ad hoc questionnaire administered to the subjects in an interview. General cognitive performance (GCP), episodic memory (EM), and working memory (WM) have been evaluated. The Mini-Mental State Examination and the total score of Spanish version of the Cambridge Cognitive Examination evaluated the GCP. Episodic memory was assessed with the Spanish version of the California Verbal Learning. Working memory was evaluated by the counting span task and the listening span task. RESULTS: The satisfactory fit of the proposed model confirmed the direct effects of CR on WM and GCP at baseline, as well as indirect effects on EM and WM at first and second follow-up. Indirect effects of CR on other cognitive constructs via WM were observed over time. CONCLUSION: The proposed model is useful for measuring the influence of CR on cognitive performance over time. Cognitive response acquired throughout life may influence cognitive performance in old age and prevent cognitive deterioration, thus increasing processing resources via WM.

Machine learning approaches to studying the role of cognitive reserve in conversion from mild cognitive impairment to dementia.

OBJECTIVES: The overall aim of the present study was to explore the role of cognitive reserve (CR) in the conversion from mild cognitive impairment (MCI) to dementia. We used traditional and machine learning (ML) techniques to compare converter and nonconverter participants. We also discuss the predictive value of CR proxies in relation to the ML model performance. METHODS: In total, 169 participants completed the longitudinal study. Participants were divided into a control group and three MCI subgroups, according to the Petersen criteria for diagnosis. Information about the participants was compared using nine ML classification techniques. Seven relevant performance metrics were computed in order to evaluate the accuracy of prediction regarding converter and nonconverter participants. RESULTS: ML algorithms applied to socio-demographic, basic health, and CR proxy data enabled prediction of conversion to dementia. The best performing models were the gradient boosting classifier (accuracy (ACC) = 0.93; F1 = 0.86, and Cohen κ = 0.82) and random forest classifier (ACC = 0.92; F1 = 0.79, and Cohen κ = 0.71). Use of ML techniques corroborated the protective role of CR as a mediator of conversion to dementia, whereby participants with more years of education and higher vocabulary scores survived longer without developing dementia. CONCLUSIONS: We used ML approaches to explore the role of CR in conversion from MCI to dementia. The findings indicate the potential value of ML algorithms for detecting risk of conversion to dementia in cognitive aging and CR studies. Further research is required to develop an ML-based procedure that can be used to make robust predictions.

Assessing mild behavioral impairment with the mild behavioral impairment checklist in people with subjective cognitive decline.

ABSTRACTObjectives:To estimate the prevalence of Mild Behavioral Impairment (MBI) in people with Subjective Cognitive Decline (SCD), and validate the Mild Behavioral Impairment Checklist (MBI-C) with respect to score distribution, sensitivity, specificity, and utility for MBI diagnosis, as well as correlation with other neuropsychological tests. DESIGN: Correlational study with a convenience sampling. Descriptive, logistic regression, ROC curve, and bivariate correlations analyses were performed. SETTING: Primary care health centers. PARTICIPANTS: 127 patients with SCD. MEASUREMENTS: An extensive evaluation, including Questionnaire for Subjective Memory Complaints, Mini-Mental State Examination, Cambridge Cognitive Assessment-Revised, Neuropsychiatric Inventory-Questionnaire (NPI-Q), the Geriatric Depression Scale-15 items (GDS-15), the Lawton and Brody Index and the MBI-C, which was administered by phone to participants' informants. RESULTS: MBI prevalence was 5.8% in those with SCD. The total MBI-C scoring was low and differentiated people with MBI at a cut-off point of 8.5 (optimizing sensitivity and specificity). MBI-C total scoring correlated positively with NPI-Q, Questionnaire for Subjective Cognitive Complaints (QSCC) from the informant and GDS-15. CONCLUSIONS: The phone administration of the MBI-C is useful for detecting MBI in people with SCD. The prevalence of MBI in SCD was low. The MBI-C detected subtle Neuropsychiatric symptoms (NPS) that were correlated with scores on the NPI-Q, depressive symptomatology (GDS-15), and memory performance perceived by their relatives (QSCC). Next steps are to determine the predictive utility of MBI in SCD, and its relation to incident cognitive decline over time.

Socioeconomic, emotional, and physical execution variables as predictors of cognitive performance in a Spanish sample of middle-aged and older community-dwelling participants.

BACKGROUND: Cognitive performance is not easily predicted, since different variables play an important role in the manifestation of age-related declines. The objective of this study is to analyze the predictors of cognitive performance in a Spanish sample over 50 years from a multidimensional perspective, including socioeconomic, affective, and physical variables. Some of them are well-known predictors of cognition and others are emergent variables in the study of cognition. METHODS: The total sample, drawn from the "Longitudinal Study Aging in Spain (ELES)" project, consisted of 832 individuals without signs of cognitive impairment. Cognitive function was measured with tests evaluating episodic and working memory, visuomotor speed, fluency, and naming. Thirteen independent variables were selected as predictors belonging to socioeconomic, emotional, and physical execution areas. Multiple linear regressions, following the enter method, were calculated for each age group in order to study the influence of these variables in cognitive performance. RESULTS: Education is the variable which best predicts cognitive performance in the 50-59, 60-69, and 70-79 years old groups. In the 80+ group, the best predictor is objective economic status and education does not enter in the model. CONCLUSIONS: Age-related decline can be modified by the influence of educational and socioeconomic variables. In this context, it is relevant to take into account how easy is to modify certain variables, compared to others which depend on each person's life course.

Temporal changes in semantic and lexical access related to mild cognitive impairment.

BACKGROUND: It has been hypothesized that the deterioration in the ability to name famous people in normal aging and cognitive impairment is a continuum in which meaning-based representations and form-based representations are differentially impaired, with early impairments in lexical access but not in semantic access. AIMS: This hypothesis is tested in a follow-up study comparing the performance of fifty-six participants with amnestic mild cognitive impairment and forty-one control participants were assessed. METHOD: A lexical task was conducted involving recognition and naming of famous people from photographs. Proportional semantic and phonological access measures were calculated. RESULTS: Comparisons revealed significant differences between baseline and follow-up, with improvements in semantic access in the control group and decrements in phonological access in the group with amnestic mild cognitive impairment. Phonological access and reaction time measures were significantly and positively correlated, and semantic access and reaction time were significantly and negatively correlated. CONCLUSIONS: These results add evidence to the hypothesis that the decrease of processing resources is related to the increase of difficulties in lexical access throughout aging. Patterns of change must be replicated over longer periods of time.

Diagnostic transitions in mild cognitive impairment by use of simple Markov models.

BACKGROUND: Mild cognitive impairment (MCI) is a complex entity, which can involve persistence of the symptoms, conversion to dementia or improvement. The aim was to study the transitions between normal cognitive ageing and three MCI subtypes by using Markov transition models for different intervals between baseline and the follow-up assessment. METHODS: A total of 294 participants over 50 years old attending primary care centres were assessed and diagnosed at baseline as multi-domain amnestic MCI (22 participants), single domain amnestic MCI (44), non-amnestic MCI (non-amnestic MCI) (26) or controls (202). We adopted an overlapping interval strategy by constructing six different mid-point time intervals according to the time between the baseline and the follow-up assessment. We used Markov transition models to study diagnostic changes in the groups in the different time intervals RESULTS: The rate of change was lowest in the control group. In the single domain amnestic MCI and non-amnestic MCI groups, the same diagnosis was usually retained or changed to normal cognitive functioning. In the multi-domain amnestic MCI group, the rate of transition to normal functioning was lowest, and the conversion to dementia was the highest of all groups. The best fit to the Markov models was found for the period between 18-21 months, whereas the worst fit was for the period between 9-15 months CONCLUSIONS: Markov models provide a comprehensive view of transitions between MCI and normal cognitive functioning. Time interval strategies seem to provide a good opportunity to monitor diagnostic transitions, although wider intervals including subsequent assessments are needed. The low rates of conversion to dementia are discussed.

Visual memory profiling with CANTAB in mild cognitive impairment (MCI) subtypes.

OBJECTIVE: Although visual memory has been shown to be impaired in amnestic mild cognitive impairment (aMCI), the differences between MCI subtypes are not well defined. The current study attempted to investigate visual memory profiles in different MCI subtypes. METHODS: One hundred and seventy volunteers aged older than 50 years performed several visual memory tests included in the CANTAB battery. Participants were classified into four groups: (1) multiple domain aMCI (mda-MCI) (32 subjects); (2) single domain aMCI (sda-MCI)(57 subjects); (3) multiple domain non amnestic MCI (mdna-MCI) (32 subjects); and (4) controls (54 healthy individuals without cognitive impairment). Parametric and non parametric analyses were performed to compare the groups and to obtain their corresponding memory profiles. RESULTS: The mda-MCI group exhibited impairments in both dimensions of episodic memory (recognition and recollection/recall), and also in learning and working memory, whereas the sda-MCI only showed impairment in recollection-delayed recall and learning. The mdna-MCI group displayed impairment in working memory but good preservation of learning and episodic memory. CONCLUSION: The CANTAB visual memory profiles may contribute to better cognitive characterization of patients with different MCI subtypes, allowing comparison across several processes involved in visual memory such as attention, recognition, recollection and working memory.

Do the Cambridge Neuropsychological Test Automated Battery episodic memory measures discriminate amnestic mild cognitive impairment?

OBJECTIVE: Although visual recognition memory and visuospatial paired associates learning has been shown to be impaired in amnestic mild cognitive impairment (aMCI), the sensitivity and specificity of the visual memory tests used to identify aMCI are not well defined. The current study attempted to analyze the sensitivity and specificity of three visual episodic memory tests (Pattern Recognition Memory [PRM], Delayed Matching to Sample [DMS], and Paired Associated Learning [PAL]) from the CANTAB, in differentiating aMCI patients from control healthy participants. METHODS: Seventy seven aMCI patients and 85 cognitive normal controls aged over 50 years performed the PRM, DMS, and PAL tests. Univariate and multivariate logistic regression and receiver operating characteristic curve analyses were used to study the relationships between aMCI and visual memory measures. RESULTS: The three Cambridge Neuropsychological Test Automated Battery measures significantly predicted aMCI. The optimal predictive model combined the total percent correct responses for PRM and DMS with the PAL total errors (six shapes adjusted), with a sensitivity of 72%, specificity of 83%, and achieved predictive accuracy of 80%. CONCLUSION: Visual episodic memory tasks such as those involved in the PRM, DMS, and PAL tests (included in the Cambridge Neuropsychological Test Automated Battery) may sensitively discriminate aMCI patients from normal controls. These tests may be useful for correct diagnosis of aMCI.

Working memory span in mild cognitive impairment. Influence of processing speed and cognitive reserve.

BACKGROUND: Mild cognitive impairment (MCI) often includes episodic memory impairment, but can also involve other types of cognitive decline. Although previous studies have shown poorer performance of MCI patients in working memory (WM) span tasks, different MCI subgroups were not studied. METHODS: In the present exploratory study, 145 participants underwent extensive cognitive evaluation, which included three different WM span tasks, and were classified into the following groups: multiple-domain amnestic MCI (mda-MCI), single-domain amnestic MCI (sda-MCI), and controls. General linear model was conducted by considering the WM span tasks as the within-subject factor; the group (mda-MCI, sda-MCI, and controls) as the inter-subject factor; and processing speed, vocabulary and age as covariates. Multiple linear regression models were also used to test the influence of processing speed, vocabulary, and other cognitive reserve (CR) proxies. RESULTS: Results indicate different levels of impairment of WM, with more severe impairment in mda-MCI patients. The differences were still present when processing resources and CR were controlled. CONCLUSIONS: Between-group differences can be understood as a manifestation of the greater severity and widespread memory impairment in mda-MCI patients and may contribute to a better understanding of continuum from normal controls to mda-MCI patients. Processing speed and CR have a limited influence on WM scores, reducing but not removing differences between groups.

Predicting progression of cognitive decline to dementia using dyadic patterns of subjective reporting: evidence from the CompAS longitudinal study.

Objective: To analyze the validity of self and informant reports, depressive symptomatology, and some sociodemographic variables to predict the risk of cognitive decline at different follow-up times. Methods: A total of 337 participants over 50 years of age included in the CompAS and classified as Cognitively Unimpaired (CU), Subjective Cognitive Decline (SCD) and Mild Cognitive Impairment (MCI) groups were assessed at baseline and three follow-ups. A short version of the QAM was administered to assess the severity of subjective cognitive complaints (SCCs), and the GDS-15 was used to evaluate the depressive symptoms. At each follow-up assessment, participants were reclassified according to the stability, regression or progression of their conditions. Logistic regression analysis was used to predict which CU, SCD and MCI participants would remain stable, regress or progress at a 3rd follow-up by using self- and informant-reported complaints, depressive symptomatology, age and education at baseline and 2nd follow-ups as the predictive variables. Results: Overall, self-reported complaints predicted progression between the asymptomatic and presymptomatic stages. As the objective deterioration increased, i.e., when SCD progressed to MCI or dementia, the SCCs reported by informants proved the best predictors of progression. Depressive symptomatology was also a predictor of progression from CU to SCD and from SCD to MCI. Conclusion: A late increase in self-reported complaints make valid estimates to predict subjective decline at asymptomatic stages. However, an early increase in complaints reported by informants was more accurate in predicting objective decline from asymptomatic stages. Both, early and late decrease in self-reported complaints successfully predict dementia from prodromic stage. Only late decrease in self-reported complaints predict reversion from prodromic and pre-symptomatic stages.

Does tip-of-the-tongue for proper names discriminate amnestic mild cognitive impairment?

BACKGROUND: Difficulty in retrieving people's names is very common in the early stages of Alzheimer's disease and mild cognitive impairment. Such difficulty is often observed as the tip-of-the-tongue (TOT) phenomenon. The main aim of this study was to explore whether a famous people's naming task that elicited the TOT state can be used to discriminate between amnestic mild cognitive impairment (aMCI) patients and normal controls. METHODS: Eighty-four patients with aMCI and 106 normal controls aged over 50 years performed a task involving naming 50 famous people shown in pictures. Univariate and multivariate regression analyses were used to study the relationships between aMCI and semantic and phonological measures in the TOT paradigm. RESULTS: Univariate regression analyses revealed that all TOT measures significantly predicted aMCI. Multivariate analysis of all these measures correctly classified 70% of controls (specificity) and 71.6% of aMCI patients (sensitivity), with an AUC (area under curve ROC) value of 0.74, but only the phonological measure remained significant. This classification value was similar to that obtained with the Semantic verbal fluency test. CONCLUSIONS: TOTs for proper names may effectively discriminate aMCI patients from normal controls through measures that represent one of the naming processes affected, that is, phonological access.

Prevalence and correlates of cognitive impairment in adults with subjective memory complaints in primary care centres.

AIMS: To examine the prevalence and correlates of cognitive impairment (CI) in adults over 50 years old attending primary care centres with complaints of memory failure. METHODS: A sample of 580 individuals aged 50+ years with no previous diagnosis of dementia was assessed by use of the Mini Mental State Examination, the Cambridge Cognitive Assessment-Revised and the California Verbal Learning Test - to evaluate CI-dependent variables - and administration of a questionnaire on memory complaints and other instruments - to measure correlates. RESULTS: The prevalence of CI was 46.20% and positive associations were found for age, gender, level of education, subjective memory complaints, instrumental activities of daily living, reading habits and frequency of leisure activities. In the logistic regression, modelled CI was associated with older age, gender (49.12% women, 39.66% men), instrumental activities of daily living, and reading habits. CONCLUSION: Almost half of the adults aged 50+ years attending primary care centres with subjective memory complaints were affected by CI. Early evaluation of cognitive functioning is essential to establish adequate preventive and intervention strategies.

Tip-of-the-tongue in aging: influence of vocabulary, working memory and processing speed.

BACKGROUND AND AIMS: It is well known that tip-of-the-tongue (ToT) states, which are due to failure in the phonological activation of words, especially proper names, are more common in older than in younger adults. Nevertheless, the relationship between increased numbers of ToTs and cognitive aging remains unclear. The aim of the present study was to clarify this relationship by examining ToT production and the performance of cognitive tasks such as working memory and processing speed tests. METHODOLOGY: In order to study the relationships between these constructs, the performance of 133 participants in different language, working memory and processing speed tasks was analysed by use of LISREL software. RESULTS: The best fit model included direct and indirect effects of age, mediated by cognitive variables, on lexical production variables. The model incorporated the indirect effects of age on vocabulary through working memory and also the indirect effect of age on ToT through processing speed. CONCLUSION: The results indicate negative modulation of slowed processing in the age-related increase of ToT and positive modulation of working memory in vocabulary, as well as an absence of any relation between vocabulary and ToT. Assuming that ToT events involve controlled processes, the relationship between slowed processing and ToT in aging could be interpreted as reflecting controlled compensatory mechanisms.

Cognitive reserve and mental health in cognitive frailty phenotypes: Insights from a study with a Portuguese sample.

Background: Research on prevalence of cognitive frailty phenotypes in community-dwelling older adults in different countries is important to estimate their prevalence and to determine the influence of cognitive reserve and mental health in order to prevent frailty. The aims of this study were to estimate the prevalence of reversible and potentially reversible cognitive frailty (R-CF, PR-CF) in a Portuguese sample of old adults and explore the associations between these phenotypes and demographic, comorbidity, social support, cognitive reserve and mental health factors. Methods: We assessed frailty (Fried criteria) in 250 community-dwelling older adults (179 women) aged 60 years or over (mean 71.04 years) without dementia, neurological or psychiatric disorders. Subjective cognitive decline and Mild cognitive impairment were diagnosed according to standard criteria. The questionnaires Charlson Index, Medical Outcomes Study Social Support, Cognitive Reserve Index and General Health were used for assessing comorbidity, social support, cognitive reserve and mental health, respectively. Results: Prevalence of R-CF was 14%, and that of PR-CF, 15.2%. Cognitive frailty profiles differed significantly in relation to education, comorbidity, mental health, and cognitive reserve, but not in age or sex. Multivariate logistic regression showed that age, sex, comorbidity, social support, mental health, and cognitive reserve together predicted R-CF and PR-CF (90% specificity 75% sensitivity) with significant OR for mental health and cognitive reserve. Discussion: Cognitive reserve and mental health are important factors predicting R-CF and PR-CF. We recommend assessing these factors for early detection of cognitive frailty and promoting psychological well-being and lifestyles that increase cognitive reserve in adults.

Do informant-reported subjective cognitive complaints predict progression to mild cognitive impairment and dementia better than self-reported complaints in old adults? A meta-analytical study.

BACKGROUND: Subjective cognitive complaints (SCCs) are considered a risk factor for objective cognitive decline and conversion to dementia. The aim of this study was to determine whether self-reported or informant-reported SCCs best predict progression to mild cognitive impairment (MCI) and/or dementia. METHODS: We reviewed prospective longitudinal studies of Cognitively Unimpaired (CU) older adults with self-reported and informant-reported SCCs at baseline, assessed by questions or questionnaires that considered the transition to MCI and/or dementia. A random-effects meta-analysis was performed to obtain pooled estimates and 95% CIs. RESULTS: Both self-reported and informant-reported SCCs are associated with an elevated risk of transition from CU to MCI and/or dementia. The association appears stronger and more robust for informant-reported data [1.38, with a 95% CI of 1.16 -1.64, p < 0.001] than for self-reported data [1.27 (95% CI 1.06 - 1.534, p = 0.011]. CONCLUSIONS: Our results suggest that corroborated information from one informant could provide important details for distinguishing between normal aging and clinical states.

Relevance of Complaint Severity in Predicting the Progression of Subjective Cognitive Decline and Mild Cognitive Impairment: A Machine Learning Approach.

BACKGROUND: The presence of subjective cognitive complaints (SCCs) is a core criterion for diagnosis of subjective cognitive decline (SCD); however, no standard procedure for distinguishing normative and non-normative SCCs has yet been established. OBJECTIVE: To determine whether differentiation of participants with SCD according to SCC severity improves the validity of the prediction of progression in SCD and MCI and to explore validity metrics for two extreme thresholds of the distribution in scores in a questionnaire on SCCs. METHODS: Two hundred and fifty-three older adults with SCCs participating in the Compostela Aging Study (CompAS) were classified as MCI or SCD at baseline. The participants underwent two follow-up assessments and were classified as cognitively stable or worsened. Severity of SCCs (low and high) in SCD was established by using two different percentiles of the questionnaire score distribution as cut-off points. The validity of these cut-off points for predicting progression using socio-demographic, health, and neuropsychological variables was tested by machine learning (ML) analysis. RESULTS: Severity of SCCs in SCD established considering the 5th percentile as a cut-off point proved to be the best metric for predicting progression. The variables with the main role in conforming the predictive algorithm were those related to memory, cognitive reserve, general health, and the stability of diagnosis over time. CONCLUSION: Moderate to high complainers showed an increased probability of progression in cognitive decline, suggesting the clinical relevance of standard procedures to determine SCC severity. Our findings highlight the important role of the multimodal ML approach in predicting progression.