The Role of Cognitive Reserve in Protecting Cerebellar Volumes of Older Adults with mild Cognitive Impairment.

The present study aims to investigate the relationship between cerebellar volumes and cognitive reserve in individuals with Mild Cognitive Impairment (MCI). A description of proxies of cerebellar cognitive reserve in terms of different volumes across lobules is also provided. 36 individuals with MCI underwent neuropsychological (MoCA, MMSE, Clock test, CRIq) assessment and neuroimaging acquisition with magnetic resonance imaging at 3 T. Simple linear correlations were applied between cerebellar volumes and cognitive measures. Multiple linear regression models were then used to estimate standardized regression coefficients and 95% confidence intervals. Simple linear correlations between cerebellar lobules volumes and cognitive features highlighted a significant association between CRIq_Working activity and specific motor cerebellar volumes: Left_V (ρ = 0.40, p = 0.02), Right_V (r = 0.42, p = 0.002), Vermis_VIIIb (ρ = 0.47, p = 0.003), Left_X (ρ = -0.46, p = 0.002) and Vermis_X (r = 0.35, p = 0.03). Furthermore, CRIq_Working activity scores correlated with certain cerebellar lobules implicated in cognition: Left_Crus_II, Vermis VIIb, Left_IX. MMSE was associated only with the Right_VIIB volume (r = 0.35, p = 0.02), while Clock Drawing Test scores correlated with both Left_Crus_I and Right_Crus_I (r = -0.42 and r = 0.42, p = 0.02, respectively). This study suggests that a higher cognitive reserve is associated with specific cerebellar lobule volumes and that Working activity may play a predominant role in this association. These findings contribute to the understanding of the relationship between cerebellar volumes and cognitive reserve, highlighting the potential modulatory role of Working activity on cerebellum response to cognitive decline.

Mood moderates the effects of prefrontal tDCS on executive functions: A meta-analysis testing the affective state-dependency hypothesis.

BACKGROUND: In recent decades, numerous studies have investigated the effects of transcranial direct current stimulation (tDCS) on cognitive functioning. However, results of these studies frequently display inconsistency and pose challenges regarding replicability. The present work aimed at testing the hypothesis of mood as potential moderator of prefrontal tDCS effects on executive functions (EF). This hypothesis refers to the relationship between mood and EF, as well as to the association of mood with the dorsolateral prefrontal cortex (dlPFC) activity. METHODS: We conducted a meta-analysis of 11 articles where the dlPFC was stimulated with anodal tDCS, EF were measured, and mood was assessed prior to the stimulation. We then conducted a meta-regression to examine whether mood moderated the tDCS effects on EF. RESULTS: While no significant effect of tDCS on EF emerged from the meta-analysis, the meta-regression indicated that mood plays a significant role as moderator, with greater tDCS effects on EF in individuals with higher depressive symptoms. LIMITATIONS: The limited number of studies included, the heterogeneous samples considered, and the limited generalizability to other non-invasive brain stimulation techniques and affective states. CONCLUSIONS: Findings suggest that evaluating mood prior to stimulation could increase the sensitivity and specificity of tDCS application, and provide the first meta-analytic evidence in favor of the affective state-dependency hypothesis.

A meta-analysis of non-invasive brain stimulation (NIBS) effects on cerebellar-associated cognitive processes.

Non-invasive brain stimulation (NIBS) techniques, including transcranial magnetic stimulation (TMS) and transcranial electrical stimulation (tES), have provided valuable insights into the role of the cerebellum in cognitive processes. However, replicating findings from studies involving cerebellar stimulation poses challenges. This meta-analysis investigates the impact of NIBS on cognitive processes associated with the cerebellum. We conducted a systematic search and analyzed 66 studies and 91 experiments involving healthy adults who underwent either TMS or transcranial direct current stimulation (tDCS) targeting the cerebellum. The results indicate that anodal tDCS applied to the medial cerebellum enhances cognitive performance. In contrast, high-frequency TMS disrupts cognitive performance when targeting the lateral cerebellar hemispheres or when employed in online protocols. Similarly, low-frequency TMS and continuous theta burst stimulation (cTBS) diminish performance in offline protocols. Moreover, high-frequency TMS impairs accuracy. By identifying consistent effects and moderators of modulation, this meta-analysis contributes to improving the replicability of studies using NIBS on the cerebellum and provides guidance for future research aimed at developing effective NIBS interventions targeting the cerebellum.

Trauma Shaping the Psychopathological Correlates of Patients with Long-COVID: A 6-Months Longitudinal Study with Repeated Measures Mixed Models.

This research aimed at investigating how the experience of trauma can influence the psychological correlates of long-COVID over time in a clinical sample of patients hospitalized because of COVID-19. Through a longitudinal research design, 70 post-acute patients with COVID-19 were followed-up after hospital discharge in 3-time points up to 6 months and completed the Post-traumatic Stress Disorder Checklist for DSM-5 (PCL-5) and the Symptoms Checklist-90-Revised (SCL-90 R). Repeated measures mixed models with random intercept were used to evaluate the effect of trauma (yes/no) over time (T1, T2, T3) on the SCL-90-R scales. Results showed that patients with trauma display significantly worse psychological outcomes in all the SCL-90-R dimensions [all padj < .05 for the principal effects of trauma(y)], especially in symptoms of depression [time 2 vs time 1*trauma(y): b = -3.86, 95%CI (-7.18, -0.53), padj = .035; time 3 vs time 1*trauma(y): b = -4.77, 95%CI (-8.10, -1.45), padj = .011], anxiety [time 3 vs time 1*trauma(y): b = -4.54, 95%CI (-7.72, -1.37), padj = .011], and obsessive-compulsive difficulties [time 3 vs time 1*trauma(y): b = -4.03, 95%CI (-7.20, -0.86), padj = .027]. These findings shed light on the long-term psychological consequences of COVID-19 among hospitalized patients and highlight the key role of trauma, suggesting its assessment to tailor psychological interventions.

Eye-to-Hand Coordination in Obstructive Sleep APNEA Syndrome: a Descriptive Study.

OBJECTIVE: Psychomotor slowdown was observed in individuals with Obstructive Sleep Apnea Syndrome (OSAS). Previous studies evaluated separately cognitive and motor reaction times, finding that OSAS individuals show a specific impairment in the latter. The present study investigates whether eye-to-hand coordination (EHC), a specific psychomotor ability, is compromised in OSAS. METHOD: The EHC was measured in 30 OSAS individuals who were matched with 30 healthy controls by the Two-Hand Coordination Test analyzing the speed, accuracy, and coordination; the role of these variables was investigated in predicting the group they belonged to. RESULTS: The OSAS participants showed poorer performance in the execution accuracy (t(55) = -3.36, d'Cohen = -0.89, p ≤ .001), which was also found to be the only predictor of the belonging to group (ß = 0.43 (0.18), p < .05). CONCLUSIONS: The OSAS individuals show impairments in EHC and in correcting their error (executive slowdown). This is the first investigation exploring EHC coordination in this population and contributes in understanding the psychomotor slowness characterizing OSAS.

Recognizing Depression in the Elderly: Practical Guidance and Challenges for Clinical Management.

Depression is one of the most common mood disorders in the late-life population and is associated with poor quality of life and increased morbidity, disability and mortality. Nevertheless, in older adults, it often remains undetected and untreated. This narrative review aims at giving an overview on the main definitions, clinical manifestations, risk and protective factors for depression in the elderly, and at discussing the main reasons for its under/misdiagnosis, such as cognitive decline and their overlapping symptomatology. A practical approach for the global and multidisciplinary care of the older adult with depression, derived from cross-checking evidence emerging from the literature with everyday clinical experience, is thus provided, as a short and flexible "pocket" guide to orient clinicians in recognizing, diagnosing and treating depression in the elderly.

Risk and Protective Factors of Psychological Distress in Patients Who Recovered From COVID-19: The Role of Cognitive Reserve.

Recent studies reported the development of psychological distress symptoms in patients who recovered from COVID-19. However, evidence is still scarce and new data are needed to define the exact risk and protective factors that can explain the variability in symptoms manifestation. In this study, we enrolled 257 patients who recovered from COVID-19 and we evaluated the levels of psychological distress through the Symptoms Checklist-90-R scale. Data concerning illness-related variables were collected from medical records, while the presence of subjective cognitive difficulties, both before and after the illness, as well as the level of the cognitive reserve (CR), were assessed over a clinical interview. Results revealed that being female and reporting the presence of subjective cognitive difficulties after COVID-19 were associated with higher levels of psychological distress. At the same time, being admitted to the hospital and having a high CR were protective factors. Adding new information to this emerging research field, our results highlight the importance of a complete psychological and cognitive assessment in patients with COVID-19.

A Circadian Hygiene Education Initiative Covering the Pre-pandemic and Pandemic Period Resulted in Earlier Get-Up Times in Italian University Students: An Ecological Study.

The aims of the present study were to obtain sleep quality and sleep timing information in a group of university students and to evaluate the effects of a circadian hygiene education initiative. All students of the University of Padova (approximately 64,000) were contacted by e-mail (major campaigns in October 2019 and October 2020) and directed to an ad hoc website for collection of demographics and sleep quality/timing information. Participants (n = 5,740) received one of two sets of circadian hygiene advice ("A regular life" or "Bright days and dark nights"). Every month, they were then asked how easy it had been to comply and provided with the advice again. At any even month from joining, they completed the sleep quality/timing questionnaires again. Information on academic performance was obtained post hoc, together with representative samples of lecture (n = 5,972) and examination (n = 1,800) timings, plus lecture attendances (n = 25,302). Fifty-two percent of students had poor sleep quality, and 82% showed signs of social jetlag. Those who joined in October 2020, after several months of lockdown and distance learning, had better sleep quality, less social jetlag, and later sleep habits. Over approximately a year, the "Bright days and dark nights" advice resulted in significantly earlier get-up times compared with the "A regular life" advice. Similarly, it also resulted in a trend toward earlier midsleep (i.e., the midpoint, expressed as clock time, between sleep onset and sleep offset) and toward a decrease in the latency between wake-up and get-up time, with no impact on sleep duration. Significant changes in most sleep quality and sleep timing variables (i.e., fewer night awakenings, less social jetlag, and delayed sleep timing during lock-down) were observed in both advice groups over approximately a year, mostly in association with pandemic-related events characterizing 2020. Early chronotype students had better academic performances compared with their later chronotype counterparts. In a multivariate model, sleep quality, chronotype and study subject (science and technology, health and medical, or social and humanities) were independent predictors of academic performance. Taken together, these results underlie the importance of designing circadian-friendly university timetables.

Anxiety predicts impulsive-compulsive behaviours in Parkinson's disease: Clinical relevance and theoretical implications.

Patients with Parkinson's disease (PD) often present symptoms of anxiety, depression and apathy. These negative affect manifestations have been recently associated with the presence of impulsive compulsive behaviours (ICBs). However, their relation with the use of dopamine replacement therapy (DRT), a renewed risk factor for ICBs, is still not fully understood. Elucidating the role of these different ICBs predictors in PD could inform both prevention/intervention recommendations as well as theoretical models. In the present study, we have analysed data collected in 417 PD patients, 50 patients with Parkinsonian symptoms but with scan without evidence of dopaminergic deficit (SWEDD), and 185 healthy controls (HC). We examined each patient's clinical profile over a two-year time window, investigating the role of both negative affect and DRT on ICBs. Results confirmed the presence of higher levels of anxiety in both the clinical groups, and of higher level of ICBs in SWEDD patients, respect to both PD and HC. Mixed model analyses revealed a statistically significant association between anxiety and ICBs in the SWEDD patients who did not take any DRT. Findings suggest the independence between anxiety and DRT in ICBs development, and provide new evidence for the motivational opponency theoretical framework.

The University of Padua salivary-based SARS-CoV-2 surveillance program minimized viral transmission during the second and third pandemic wave.

BACKGROUND: The active surveillance of students is proposed as an effective strategy to contain SARS-CoV-2 spread and prevent schools' closure. Saliva for molecular testing is as sensitive as naso-pharyngeal swab (NPS), self-collected and well accepted by participants. This prospective study aimed to verify whether the active surveillance of the Padua University employees by molecular testing of self-collected saliva is an effective and affordable strategy for limiting SARS-CoV-2 spread. METHODS: A surveillance program based on self-collection of saliva every 2 weeks (October 2020-June 2021) was conducted. Among 8183 employees of the Padua University, a total of 6284 subjects voluntarily took part in the program. Eight collection points guaranteed the daily distribution and collection of barcoded salivary collection devices, which were delivered to the laboratory by a transport service for molecular testing. Quarantine of positive cases and contact tracing were promptly activated. RESULTS: Among 6284 subjects, 206 individuals were SARS-CoV-2 positive (99 by salivary testing; 107 by NPS performed for contact tracing or symptoms). The cumulative SARS-CoV-2 incidence in this cohort was 3.1%, significantly lower than that of employees not in surveillance (8.0%), in Padua (7.1%) and in the Veneto region (7.2%). Employees with positive saliva results were asymptomatic or had mild symptoms. The levels of serum antibodies after 3 months from the infection were correlated with age and Ct values, being higher in older subjects with greater viral loads. CONCLUSIONS: Salivary-based surveillance with contact tracing effectively allowed to limit SARS-CoV-2 contagion, also in a population with a high incidence.

Cognitive and Psychological Sequelae of COVID-19: Age Differences in Facing the Pandemic.

Literature about the novel Coronavirus (COVID-19) is currently focusing on the potential cognitive and neuropsychiatric sequelae observed in individuals receiving intensive care unit (ICU) treatments. The aim of the present study is to evaluate the differences in cognitive and psychological sequelae of COVID-19 between younger and older adults, regardless of being admitted to the ICU or not. The study involved 299 recovered individuals (from 18 to 90 years old), who underwent a comprehensive cognitive and psychological assessment. Linear regression models were conducted separately for Montreal Cognitive Assessment (MoCA) test and Post-traumatic Stress Disorder Checklist (PCL) scores to investigate the effect of socio-demographic and clinical characteristics on them. Separate linear regression models were then applied sorting participants by age: younger adults (<65 years) and older adults (≥65 years). In the whole sample, PCL scores were predicted by the intensity of care received, by being intubated, and by the persistence of cough after 1 month after hospitalization. Only age had instead an effect on cognition. In younger adults, PCL scores were predicted by the presence of neurological symptoms, by the intensity of care received, and by being intubated; MoCA scores were only predicted by the intensity of care received. No significant associations were found in older adults. Psychological negative effects of the COVID-19 pandemic particularly affect individuals under 65 years old, who also subjectively report cognitive sequelae associated with the infection. Individuals over 65 years old, instead, seem to be free from psychological and cognitive difficulties due to COVID-19.

Smart Co-housing for People With Disabilities: A Preliminary Assessment of Caregivers' Interaction With the DOMHO System.

Millions of people with motor and cognitive disabilities face hardships in daily life due to the limited accessibility and inclusiveness of living spaces which limit their autonomy and independence. The DOMHO project deals with these fundamental issues by leveraging an innovative solution: a smart co-housing apartment. Besides, the project aims at exploiting the well know effects of co-housing on individuals' health and well-being in combination with ambient assisted living technologies. The present study focused on the interaction of caregivers with the control application of an integrated smart system. Participants performed different tasks, fill out a questionnaire, and were interviewed. Performance and usability of the user interface, trust in technology, privacy, and attitudes towards home automation were explored. A series of guidelines for domotic technology control interfaces design was identified, and a high level of trust in these advanced tools was shown. Caregivers considered smart technologies as a work aid and a means for enhancing autonomy and life quality for users with disabilities.

Perception of stress and cognitive efficiency in older adults with mild and moderate dementia during the COVID-19-related lockdown.

AIM: Many studies have been carried out with the aim of understanding the manifold effects of the novel coronavirus (Covid-19) on individuals' clinical and psychological states. This paper deals with perceived stress (PS) and cognitive efficiency (CE) in older adults with dementia during the first wave of the pandemic. The study also investigated the potential effects of PS and CE on participants' cognitive functioning. The modulating effect of cognitive reserve (CR) on these variables was also considered, given its well-known role in the onset and evolution of neurodegenerative diseases. METHOD: Thirty-eight older adults with mild/moderate dementia (mean age: 81.47 ± 5.05; mean MMSE pre-lockdown: 24.03 ± 3.14) were recruited for this study from March to May [4]. Two questionnaires, the Perceived Stress Scale (PSS) and the FLEI Mental Ability Questionnaire (FLEI), were administered to all participants by telephone every two weeks during lockdown (T1: early April, T2: mid-April, T3: early May). After lockdown, their neuropsychological and psychological profiles were assessed. Linear mixed-effects models were used to investigate changes over time. RESULTS: The level of PS increased at both Time 2 and Time 3 (f2 = 0.10). Cognitive functioning worsened during lockdown, resulting in lower scores at the post-lockdown evaluation (f2s = 0.09 and 0.06 for MMSE and ENB-2, respectively). The decrease in these scores was not associated with either PS or CE. Although the size of these effects was rather small, their clinical relevance is not negligible. CONCLUSION: Individuals with dementia seem to have experienced stress (S) during the first-wave of lockdown related to Covid-19. Cognition worsened during the pandemic, in accordance with the neurodegenerative nature of the disease, but it was unrelated to PS and CE.

Novel insights into the relationship between cerebellum and dementia: A narrative review as a toolkit for clinicians.

The role of the cerebellum in neurodegenerative disorders that target cognitive functions has been a subject of increasing interest over the past years. However, a review focused on making clinicians more aware of the role of the cerebellum in dementia is still missing. This narrative review explores the possible factors explaining the involvement of the cerebellum in different kinds of dementia by providing more insights on how this structure can be relevant in clinical practice. It emerged that, despite overlapping in specific areas, structural cerebellar alterations in dementia show a certain degree of disease-specificity. Furthermore, the relevance of cerebellar changes in dementia is corroborated by correlations observed between their topography and cognitive symptomatology, as well as by its previously ignored involvement of the cerebellum in early stages of dementia. Despite needing further investigations, these findings could become a useful diagnostic aid for clinicians that should not be overlooked, in particular for those individuals who do not show distinct and manifest brain or neuropsychological alterations, but that still make clinicians suspect the presence of a neurocognitive disease.

Neurophysiological and behavioural effects of conventional and high definition tDCS.

High-definition transcranial direct current stimulation (HD-tDCS) seems to overcome a drawback of traditional bipolar tDCS: the wide-spread diffusion of the electric field. Nevertheless, most of the differences that characterise the two techniques are based on mathematical simulations and not on real, behavioural and neurophysiological, data. The study aims to compare a widespread tDCS montage (i.e., a Conventional bipolar montage with extracephalic return electrode) and HD-tDCS, investigating differences both at a behavioural level, in terms of dexterity performance, and a neurophysiological level, as modifications of alpha and beta power as measured with EEG. Thirty participants took part in three sessions, one for each montage: Conventional tDCS, HD-tDCS, and sham. In all the conditions, the anode was placed over C4, while the cathode/s placed according to the montage. At baseline, during, and after each stimulation condition, dexterity was assessed with a Finger Tapping Task. In addition, resting-state EEG was recorded at baseline and after the stimulation. Power spectrum density was calculated, selecting two frequency bands: alpha (8-12 Hz) and beta (18-22 Hz). Linear mixed effect models (LMMs) were used to analyse the modulation induced by tDCS. To evaluate differences among the montages and consider state-dependency phenomenon, the post-stimulation measurements were covariate-adjusted for baseline levels. We observed that HD-tDCS induced an alpha power reduction in participants with lower alpha at baseline. Conversely, Conventional tDCS induced a beta power reduction in participants with higher beta at baseline. Furthermore, data showed a trend towards a behavioural effect of HD-tDCS in participants with lower beta at baseline showing faster response times. Conventional and HD-tDCS distinctively modulated cortical activity. The study highlights the importance of considering state-dependency to determine the effects of tDCS on individuals.

Religious assessment in Italian older adults: psychometric properties of the Francis Scale of Attitude toward Christianity and the Behavioral Religiosity Scale.

OBJECTIVES: Studies have shown that religiosity (R) and spirituality (S) can positively impact older adults' life. Nevertheless, no validated tools for measuring these constructs in the older Italian population are currently available. This study investigates the psychometric properties of two of the most common measures of R and S in the literature: the Francis Scale of Attitude toward Christianity short form (FSACsf) and the Behavioral Religiosity Scale (BRS). METHOD: 313 older Italians completed the questionnaires anonymously. The functioning of the items and the response scales, the factor structure, age invariance and internal consistency of both scales were investigated. RESULTS: Each scale defines a substantively unidimensional variable. Moreover, items seem, on the whole, to be well formulated. The values of the Rasch-Andrich thresholds suggest that the response scale of the FSACsf was adequate for measuring spirituality. However, this was not the case for BRS, where the response categories needed to be collapsed to measure behavioral religiosity properly. Age invariance was confirmed for each scale. Cronbach's α, composite reliability and person separation reliability revealed both scales to be internally consistent. DISCUSSION: The results suggest that the scales have solid psychometric properties, and can therefore be considered valid, reliable tools for investigating religiosity and spirituality in older people.

Acetylcholinesterase inhibitors and cognitive stimulation, combined and alone, in treating individuals with mild Alzheimer's disease.

BACKGROUNDS: Acetylcholinesterase inhibitors (AChEI) and cognitive stimulation (CS) are the standard pharmacological and non-pharmacological treatments for Alzheimer's disease (AD). AIMS: The aim of this study was to investigate the effects of these treatments, alone or combined, on the neuropsychological profiles of patients with AD. METHODS: Forty participants were assigned to three groups receiving either only AChEI (n = 14), AChEI + CS (n = 15), or only CS (n = 11). Cognition was evaluated at baseline and after three months. Linear mixed-effects models were used to investigate differences among the treatments in terms of changes in the patients' neuropsychological profiles. RESULTS: Results, although preliminary because of the small sample size, suggest that a general improvement was found in patients who received AChEI + CS and those who received only CS compared with those who received only AChEI. Interestingly, individuals who received only CS showed a significant improvement in immediate memory recall than those who received only AChEI. Furthermore, the group receiving AChEI + CS showed an improvement in delayed recall than the other two groups. DISCUSSION: The combination of AChEI and CS seems to have the greatest benefit for patients with mild AD. More interestingly, CS alone is more effective than AChEI alone, even in improving memory, considered to be the "lost" cognitive domain in AD.

The Role of Motivation and Anxiety on Error Awareness in Younger and Older Adults.

Aging is associated with several changes in cognitive functions, as well as in motivational and affective processes, which in turn interact with cognitive functions. The present study aimed to investigate error awareness (EA), which declines with aging, in relation to motivation and anxiety. Adopting an experimental task, we firstly tested the hypothesis that EA could be enhanced through reward motivation. Secondly, we explored the relation between state and trait anxiety and EA, investigating the hypothesis of an association between EA and anxiety, and between anxiety and the potential benefit of motivation on EA. Thirty healthy younger (age range: 19-35 years; mean age 25.4 ± 5.1; 10 M) and 30 healthy older adults (age range: 61-83 years; mean age 69.7 ± 5.5; 12 M) took part in the study and performed both the classic Error Awareness Task (EAT) and one experimental task, called the Motivational EAT. In this new task, motivational incentives were delivered after aware correct responses and aware errors. For every participant, standard measures of state and trait anxiety and cognitive functions were collected. Confirming the presence of a significant age-related EA decline, results did not reveal any influence of reward motivation on EA, nor any relation between EA and anxiety. However, both younger and older adults had longer response times (RTs) and made more errors during the Motivational EAT, with the more anxious participants showing the greater RT slowing. Findings suggest that reward motivation might not be always beneficial for cognitive performance, as well as that anxiety does not relate to EA capacity. Results also recommend further investigation, as well as the assessment of EA in patients with either motivational deficits like apathy, and/or with anxiety disorders.

Investigating the Accessibility of Voice Assistants With Impaired Users: Mixed Methods Study.

BACKGROUND: Voice assistants allow users to control appliances and functions of a smart home by simply uttering a few words. Such systems hold the potential to significantly help users with motor and cognitive disabilities who currently depend on their caregiver even for basic needs (eg, opening a door). The research on voice assistants is mainly dedicated to able-bodied users, and studies evaluating the accessibility of such systems are still sparse and fail to account for the participants' actual motor, linguistic, and cognitive abilities. OBJECTIVE: The aim of this work is to investigate whether cognitive and/or linguistic functions could predict user performance in operating an off-the-shelf voice assistant (Google Home). METHODS: A group of users with disabilities (n=16) was invited to a living laboratory and asked to interact with the system. Besides collecting data on their performance and experience with the system, their cognitive and linguistic skills were assessed using standardized inventories. The identification of predictors (cognitive and/or linguistic) capable of accounting for an efficient interaction with the voice assistant was investigated by performing multiple linear regression models. The best model was identified by adopting a selection strategy based on the Akaike information criterion (AIC). RESULTS: For users with disabilities, the effectiveness of interacting with a voice assistant is predicted by the Mini-Mental State Examination (MMSE) and the Robertson Dysarthria Profile (specifically, the ability to repeat sentences), as the best model shows (AIC=130.11). CONCLUSIONS: Users with motor, linguistic, and cognitive impairments can effectively interact with voice assistants, given specific levels of residual cognitive and linguistic skills. More specifically, our paper advances practical indicators to predict the level of accessibility of speech-based interactive systems. Finally, accessibility design guidelines are introduced based on the performance results observed in users with disabilities.