Association of Torquetenovirus Viremia with Physical Frailty and Cognitive Impairment in Three Independent European Cohorts.

INTRODUCTION: Immunosenescence and inflammaging have been implicated in the pathophysiology of frailty. Torquetenovirus (TTV), a single-stranded DNA anellovirus, the major component of the human blood virome, shows an increased replication rate with advancing age. An elevated TTV viremia has been associated with an impaired immune function and an increased risk of mortality in the older population. The objective of this study was to analyze the relation between TTV viremia, physical frailty, and cognitive impairment. METHODS: TTV viremia was measured in 1,131 nonfrail, 45 physically frail, and 113 cognitively impaired older adults recruited in the MARK-AGE study (overall mean age 64.7 ± 5.9 years), and then the results were checked in two other independent cohorts from Spain and Portugal, including 126 frail, 252 prefrail, and 141 nonfrail individuals (overall mean age: 77.5 ± 8.3 years). RESULTS: TTV viremia ≥4log was associated with physical frailty (OR: 4.69; 95% CI: 2.06-10.67, p < 0.0001) and cognitive impairment (OR: 3.49, 95% CI: 2.14-5.69, p < 0.0001) in the MARK-AGE population. The association between TTV DNA load and frailty status was confirmed in the Spanish cohort, while a slight association with cognitive impairment was observed (OR: 1.33; 95% CI: 1.000-1.773), only in the unadjusted model. No association between TTV load and frailty or cognitive impairment was found in the Portuguese sample, although a negative association between TTV viremia and MMSE score was observed in Spanish and Portuguese females. CONCLUSIONS: These findings demonstrate an association between TTV viremia and physical frailty, while the association with cognitive impairment was observed only in the younger population from the MARK-AGE study. Further research is necessary to clarify TTV's clinical relevance in the onset and progression of frailty and cognitive decline in older individuals.

Effectiveness of a chess-training program for improving cognition, mood, and quality of life in older adults: A pilot study.

BACKGROUND: Regular practice of a cognitively stimulating activity, such as chess, can help maintain a healthy cognitive, social, and psychological state during the aging process. OBJECTIVE: To evaluate the effects of a chess-training program on cognitive status, mood, and quality of life (QoL) in a sample of institutionalized and semi-institutionalized older adults. METHOD: A nonrandomized, controlled pilot study with repeated measures (pre- and post-intervention) was conducted. RESULTS: Analyses revealed a positive impact of the chess program on general cognitive status (p < 0.001) and promising evidence (p < 0.043) of an impact on attention, processing speed, and executive functions. The participants in the intervention group also showed significant improvement in QoL scores (p < 0.021). CONCLUSIONS: A 12-week chess-training protocol with two 60-minute sessions per week improved cognition and QoL in a sample of institutionalized and semi-institutionalized older adults. Further research with larger samples is needed to explore its effects in depth.

Dual and triple tasks performance in institutionalized prefrail and frail older adults.

OBJECTIVE: The aim of this pilot study was to investigate differences on dual- and triple-task performance in institutionalized prefrail and frail older adults. Performance on these tasks is relevant since many activities of daily living involve simultaneous motor and cognitive tasks. METHODS: We used a phenotypic description of frailty based on the presence or absence of five criteria related to physical fitness and metabolism (unintentional weight loss, self-reported exhaustion, muscle weakness, low gait speed, and low physical activity). Thirty-three institutionalized older adults (≥ 65 years, 78.8% females) were divided according to their frailty status. Participants completed cognitive tasks (a phonemic verbal fluency task and a visuospatial tracking task) while cycling on a stationary cycle (upper- and lower-extremity function was assessed). Cycling (number of arm and foot cycles) and cognitive (number of correct answers) performances were measured during single-, dual-, and triple-task conditions. Performances and costs of dual -and triple- tasking on cycling and cognitive performances were compared between prefrail and frail groups. RESULTS: Prefrail and frail older adults did not differ in their performance in dual-tasks; however, frail older adults showed a poorer performance in the triple-task. CONCLUSIONS: Although future studies need to confirm our observations in larger samples, this pilot study suggests that developing new tools based on triple tasking could be useful for the comprehensive assessment of frailty.

Application of light therapy in older adults with cognitive impairment: A systematic review.

This systematic review aims to assess the efficacy of light therapy on behavioural and psychological symptoms of dementia (BPSD), cognition, functional status, and quality of life in older adults with cognitive impairment; and secondarily, to identify the optimal characteristics of light therapy to establish an adequate protocol for its clinical application. We searched Web of Science and Medline databases through December 2019, resulting in 36 included articles: 3 evaluated the effects on BPSD, 25 on sleep, 12 on agitation, 10 on mood, 4 on neuropsychiatric symptoms, 4 on cognition, 2 on quality of life and 2 on functional status. Literature has shown potential evidence for positive effects of light therapy on managing sleep, behavioural and mood disturbances in people with cognitive impairment, but a limited effect on cognition, quality of life and functional status. This review provides guidelines for intervention protocols with light therapy in older people with cognitive impairment.

Serum cortisol but not oxidative stress biomarkers are related to frailty: results of a cross-sectional study in Spanish older adults.

Frailty is a multidimensional geriatric syndrome of loss of reserves and increased vulnerability to negative health outcomes. Cortisol, the major hormone of the hypothalamic pituitary adrenal (HPA) axis, and oxidative stress may be influenced by multiple endogenous and environmental factors throughout the lifespan, triggering changes in organism functioning. Association of elevated levels of cortisol and oxidative stress biomarkers with aging and several age-related diseases is well documented. However, the possible role of these factors on frailty status in older adults has not been extensively studied. Hence, the aim of this study was to conduct a cross-sectional study in 252 older adults (≥65 years old) classified according to their frailty status. Plasma cortisol and biomarkers related to oxidative stress including reactive oxygen/nitrogen species, oxidative DNA damage, and total antioxidant capacity were determined in non-frail, pre-frail, and frail subjects. Results showed significantly increasing cortisol concentrations with frailty burden, but no marked association between any oxidative stress biomarker and frailty status. In addition, dependence on activities of daily living and 10-year mortality risk were also correlated with elevated cortisol levels. Current results support the hypothesis that age-related HPA axis dysregulation is associated with frailty status, although further research is necessary to establish the role of cortisol in the pathophysiology of frailty.

Social factors and quality of life aspects on frailty syndrome in community-dwelling older adults: the VERISAÚDE study.

BACKGROUND: Frailty is a multidimensional clinical geriatric syndrome that may be reversed in its early stages. Most studies have paid attention to its physical or phenotypic boundaries, however, little is known about the social aspects surrounding this geriatric syndrome. The study examined the relationship between socio-demographic factors, social resources, quality of life and frailty in older adults. METHODS: This cross-sectional study included a representative sample (n = 749) of adults aged ≥65 years enrolled in forty-three senior centers located in North-West Spain. Socio-demographic data, social resources by the Older Americans Resources and Services Scale, quality of life by the World Health Organization's Quality of Life measure-brief version (WHOQOL-BREF), and frailty status diagnosed by the Frailty phenotype were measured. RESULTS: Female gender, age older than 75 years, single marital status, a poor quality of life, and low scores in the physical health domain of the WHOQOL-BREF were the main determinants of being non-robust. Together, these variables explained 24.4% of the variance. Age between 80 and 89 years, and a poor quality of life were the main determinants for non-robust men, whilst the physical health domain of the WHOQOL-BREF was the single main determinant for women. CONCLUSIONS: Our study found evidence that physical frailty is associated with social determinants and several quality of life domains. More research on this understudied topic is needed to avoid healthcare expenditures and improve the quality of life of non-robust elders.

Immune biomarkers in older adults: Role of physical activity.

Aging is associated with a decline in the normal functioning of the immune system. Several studies described the relationship between immunological alterations, including immunosenescence and inflammation, and aging or age-related outcomes, such as sarcopenia, depression, and neurodegenerative disorders. Physical activity is known to improve muscle function and to exert a number of benefits on older adult health, including reduced risk for heart and metabolic system chronic diseases. However, the positive influence of physical activity on the immune system has not been elucidated. In order to shed light on the role of physical activity in immune responses of older individuals, a number of immunological parameters comprising % lymphocyte subsets (CD3+, CD4+, CD8+, CD19+, and CD16+56+) and serum levels of neopterin and tryptophan metabolism products were evaluated in peripheral blood samples of older adults performing normal (N = 170) or reduced (N = 89) physical activity. In addition, the potential influence of other clinical and epidemiological factors was also considered. Results showed that subjects with reduced physical activity displayed significantly higher levels of CD4+/CD8+ ratio, kynurenine/tryptophan ratio, and serum neopterin, along with lower %CD19+ cells and tryptophan concentrations. Further, some immunological biomarkers were associated with cognitive impairment and functional status. These data contribute to reinforce the postulation that physical activity supports healthy aging, particularly by helping to protect the immunological system from aging-related changes.

Nutritional determinants of frailty in older adults: A systematic review.

BACKGROUND: Frailty is a geriatric syndrome that affects multiple domains of human functioning. A variety of problems contributes to the development of this syndrome; poor nutritional status is an important determinant of this condition. The purpose of this systematic review was to examine recent evidence regarding the association between nutritional status and frailty syndrome in older adults. METHODS: PubMed, Web of Science, and Scopus electronic databases were searched using specific key words, for observational papers that were published during the period from 2005 to February 2017 and that studied the association or relationship between nutritional status and frailty in older adults. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement was followed to assess the quality of the included articles. RESULTS: Of the 2042 studies found, nineteen met the inclusion criteria. Of these studies, five provided data on micronutrients and frailty, and reported that frailty syndrome is associated with low intakes of specific micronutrients. Five studies provided data on macronutrients and frailty, and among those studies, four revealed that a higher protein intake was associated with a lower risk of frailty. Three studies examined the relationship between diet quality and frailty, and showed that the quality of the diet is inversely associated with the risk of being frail. Two studies provided data on the antioxidant capacity of the diet and frailty, and reported that a high dietary antioxidant capacity is associated with a lower risk of developing frailty. Finally, seven studies evaluated the relationship between scores on both the Mini Nutritional Assessment (MNA) and the MNA-SF (Short Form) and frailty, and revealed an association between malnutrition and/or the risk of malnutrition and frailty. CONCLUSIONS: This systematic review confirms the importance of both quantitative (energy intake) and qualitative (nutrient quality) factors of nutrition in the development of frailty syndrome in older adults. However, more longitudinal studies on this topic are required to further understand the potential role of nutrition in the prevention, postponement, or even reversion of frailty syndrome.

Caregiver's distress related to the patient's neuropsychiatric symptoms as a function of the care-setting.

Prevalence of neuropsychiatric symptoms (NPS) and correlation between its intensity and caregiver distress were evaluated as a function of the care-setting in a cross-sectional study including 72 patient-caregiver dyads. The Neuropsychiatric Inventory and the Caregiver Distress Scale were administered. The most prevalent symptoms were: in the formal care-setting, agitation/aggression and depression/dysphoria (42.4%), and in the informal care-setting, aberrant motor behavior (59.0%). While changes in appetite and eating behaviors, depression/dysphoria and irritability/lability were more prevalent in the formal care-setting (p < .0001, p = .011, p = .021), aberrant motor behavior was more prevalent in the informal care-setting (p = .007). NPS were positively correlated with caregiver distress. High patients' scores in hallucinations, sleep and night-time disturbances, anxiety, and aberrant motor behavior were the best predictors of professional caregiver's distress. Agitation/aggression, delusions, disinhibition, apathy/indifference, depression/dysphoria, and elation/euphoria were the best predictors of informal caregiver's distress. Findings may have important clinical implications.

Health determinants of nutritional status in community-dwelling older population: the VERISAÚDE study.

OBJECTIVE: Malnutrition is a common and relevant syndrome in elderly people due to its influence on quality of life. The main aim of the present study was to identify health determinants of malnutrition or risk of malnutrition. DESIGN: Cross-sectional study collecting information on sociodemographic and health factors (co-morbidity, cognitive or affective problems, prescription medication use, frailty status, self-rated health) as determinants of nutritional status, assessed by the short form of the Mini Nutritional Assessment. SETTING: Forty-three senior centres from Galicia (north-western Spain) participated to recruit participants. SUBJECTS: A representative community-dwelling sample of 749 elderly people aged ≥65 years. RESULTS: Of the total participants, 14·3 % were malnourished/at risk of malnutrition. Presence of overweight or obesity, depressive symptoms, polypharmacy (use of five or more prescription medications), presence of pre-frailty or frailty status and poor self-rated health showed the strongest relationship to malnutrition/risk of malnutrition. This model predicted 86·0 % of the cases correctly. The best determinants for women were polypharmacy and poor self-rated health, reaching 82·8 % of cases of malnourishment/risk of malnutrition predicted correctly. In men, the main determinants were overweight or obesity, depressive symptomatology and polypharmacy, with 89·8 % of cases of malnourishmen/risk of malnutrition predicted correctly. CONCLUSIONS: Screening for nutritional status and its determinant factors should be included as part of comprehensive assessments to ensure an early screening of malnutrition and to propose possible intervention strategies that would be important for both elderly people and the health-care system.

Lymphocyte Subsets in a Population of Nonfrail Elderly Individuals.

Age-related frailty is characterized by increased vulnerability to stress due to decline in homeostatic reserve, which results in increased risk of adverse health outcomes including disability, hospitalization, and death. The relationship between frailty and immunological system alterations is well established. Thus, analysis of immunological changes, such as alterations in lymphocyte subsets, during senescence may provide useful markers for frailty and associated pathologies. Since reference ranges currently used for lymphocyte subsets do not specifically differentiate the elderly group, the aim of this study was to (1) establish reference ranges in nonfrail elderly individuals and (2) assess the evolution of these parameters with age. Further, the influence of other physiological and lifestyle factors was also evaluated. The study was performed on 144 elderly individuals (aged 65-95) from Galicia (in northwestern Spain). Percentages of lymphocyte subpopulations (CD3(+) T lymphocytes, CD4(+) T-helper lymphocytes, CD8(+) T-cytotoxic lymphocytes, CD19(+) B lymphocytes, and CD56(+)16(+) natural killer cells) were analyzed in peripheral blood by flow cytometry, and reference ranges were calculated. The individual status as nonfrail or prefrail did not markedly affect the immunological parameters, but an apparent influence of age was obtained for %CD3(+), %CD4(+), and %CD19(+) cells, all of which fell with increasing age. Women showed higher levels of %CD19(+) lymphocytes. No significant influence of smoking habits, physical activity, or drinking alcohol or caffeine beverages was observed. The results obtained may serve as a basis to establish comparisons between frail and nonfrail elderly individuals, in order to determine the usefulness of lymphocyte subsets as immunological biomarkers of frailty.

Verbal fluency, naming and verbal comprehension: three aspects of language as predictors of cognitive impairment.

OBJECTIVES: To establish the possible relationship among three components of language (verbal fluency, naming and comprehension) and cognitive impairment as well as to determine the usefulness of language assessment tests to predict or monitor the development of cognitive impairment. METHOD: A comparative, descriptive and cross-sectional study was performed on 82 subjects ≥ 65 years of age who were cognitively assessed with the Mini Mental State Examination and were divided into two groups: Group A comprised of subjects classified as levels 1, 2 and 3 on the Reisberg's Global Deterioration Scale (GDS) and group B comprised of subjects at levels 4 and 5 of the GDS. Language skills were assessed by the Verbal Fluency Test, Boston Naming Test and Token Test. RESULTS: An inverse relationship between performance on language tests and cognitive impairment level was observed with a more pronounced effect observed on fluency and comprehension tests. CONCLUSION: Language assessments, especially fluency and comprehension, were good indicators of cognitive impairment. The use of these assessments as predictors of the degree of cognitive impairment is discussed in-depth.

Toxoplasma gondii IgG Serointensity Is Positively Associated With Frailty.

BACKGROUND: Persistent inflammation related to aging ("inflammaging") is exacerbated by chronic infections and contributes to frailty in older adults. We hypothesized associations between Toxoplasma gondii (T. gondii), a common parasite causing an oligosymptomatic unremitting infection, and frailty, and secondarily between T. gondii and previously reported markers of immune activation in frailty. METHODS: We analyzed available demographic, social, and clinical data in Spanish and Portuguese older adults [N = 601; age: mean (SD) 77.3 (8.0); 61% women]. Plasma T. gondii immunoglobulin G (IgG) serointensity was measured with an enzyme-linked immunosorbent assay. The Fried criteria were used to define frailty status. Validated translations of Mini-Mental State Examination, Geriatric Depression Scale, and the Charlson Comorbidity Index were used to evaluate confounders. Previously analyzed biomarkers that were significantly associated with frailty in both prior reports and the current study, and also related to T. gondii serointensity, were further accounted for in multivariable logistic models with frailty as outcome. RESULTS: In T. gondii-seropositives, there was a significant positive association between T. gondii IgG serointensity and frailty, accounting for age (p = .0002), and resisting adjustment for multiple successive confounders. Among biomarkers linked with frailty, kynurenine/tryptophan and soluble tumor necrosis factor receptor II were positively associated with T. gondii serointensity in seropositives (p < .05). Associations with other biomarkers were not significant. CONCLUSIONS: This first reported association between T. gondii and frailty is limited by a cross-sectional design and warrants replication. While certain biomarkers of inflammaging were associated with both T. gondii IgG serointensity and frailty, they did not fully mediate the T. gondii-frailty association.

Early prefrontal activation as a mechanism to prevent forgetting in the context of interference.

OBJECTIVE: Recent research has focused on interference resolution deficits as the main cause of short-term memory decreases in aging. To determine whether activation of brain compensatory mechanisms occur during the encoding process in older people. Moreover, two different levels of interference (distraction and interruption) were presented during the maintenance period to examine how they modulate brain activity profiles. DESIGN: A delayed match-to-sample task with two experimental conditions: distraction and interruption. PARTICIPANTS: Twenty-seven young adults from Complutense University of Madrid and 20 healthy older adults from Complutense Elderly University of Madrid. MEASUREMENTS: Magnetoencephalography scans were recorded during the execution of a working memory interference task. Brain activity sources from younger and older adults during the encoding stage were compared in each condition using minimum norm estimation analyses. RESULTS: The elderly showed enhancement of prefrontal activity during early latencies of the encoding process in both conditions. In the distraction condition, enhanced activity was located in left ventrolateral prefrontal regions, whereas in the interruption condition, enhanced activity was observed in the right ventral prefrontal areas and anterior cingulate cortex. CONCLUSION: Increased recruitment of prefrontal regions in the elderly might be related to the processing depth of information, encoding of new information and semantic associations that are successfully recalled, and with interference resolution and preparatory control when the level of interference becomes higher. These prefrontal modulations during early latencies might reflect a higher top-down control of the encoding process in normal aging to prevent forgetting.

Efficacy of a computerized cognitive training application for older adults with and without memory impairments.

BACKGROUND/AIMS: It has been shown that cognitive training might help to protect against age-related cognitive decline. Our aim was to evaluate the efficacy of a computerized cognitive training application and its near transfer effects on the cognitive status of older adults. METHODS: Performance on the 7-Minute Screen at baseline and at the end of the program was analyzed by using a pre-post design. Adults aged 55 and older (n = 101; mean age ± standard deviation: 68.97 ± 5.81 years) with and without memory impairments were trained. RESULTS: Significant improvements after the training program were found in memory, visuo-spatial and verbal fluency abilities, regardless of age, gender or education. Moreover, participants without significant memory impairments and those with Age-Associated Memory Impairment gained from the program more than subjects with mild cognitive impairment. CONCLUSION: Computerized cognitive training programs, such as Telecognitio®, may be used as a practical and valuable tool in clinic to improve cognitive status.

Dysphagia and its association with other health-related risk factors in institutionalized older people: A systematic review.

BACKGROUND: Dysphagia is considered a geriatric syndrome that is characterized by inability to or difficulty in safely and effectively forming or moving the food bolus toward the esophagus. This pathology is very common and affects approximately 50% of institutionalized older people. Dysphagia is often accompanied by high nutritional, functional, social, and emotional risks. This relationship implies a higher rate of morbidity, disability, dependence, and mortality in this population. This review is aimed at studying the relationship between dysphagia and different health-related risk factors in institutionalized older people. METHOD: We conducted a systematic review. The bibliographic search was performed in the Web of Science, Medline, and Scopus databases. Data extraction and methodological quality were evaluated by two independent researchers. RESULTS: Twenty-nine studies met the inclusion and exclusion criteria. A clear relationship between the development and progression of dysphagia and a high nutritional, cognitive, functional, social, and emotional risk in institutionalized older adults was found. CONCLUSIONS: There is an important relationship between these health conditions that shows the need for research and new approaches to considerations such as their prevention and treatment as well as the design of protocols and procedures that will help reduce the percentage of morbidity, disability, dependence, and mortality in older people.

Relationship between DNA damage measured by the comet-assay and cognitive function.

Recent studies exploring the relationship between DNA damage measured by the comet assay (single-cell gel electrophoresis) and cognitive function in both animal models and humans are reviewed and summarized. This manuscript provides an overview of studies exploring cognitive dysfunction related to DNA damage due to biological ageing process, cancer treatment, adverse environmental or occupational exposures, and prenatal genotoxic exposure. The review confirms the potential of comet assay to further explore the link between DNA damage, as indicative of genomic instability, and cognitive impairment in different research and clinical areas. Analysed studies support, in fact, the significant relationship between DNA damage and cognitive impairment, mainly affecting attention, working memory and executive functions. These cognitive domains are crucial to daily functioning and occupational performance, with important clinical implications. Although evidence support the relationship between DNA damage measured by the comet assay and cognitive function in different settings, further longitudinal research is needed to disentangle the temporal relationship between them over time, and to explore the potential of comet assay-detected DNA lesions to predict response to interventions.

Suitability of salivary leucocytes to assess DNA repair ability in human biomonitoring studies by the challenge-comet assay.

The challenge-comet assay is a simple but effective approach that provides a quantitative and functional determination of DNA repair ability, and allows to monitor the kinetics of repair process. Peripheral blood mononuclear cells (PBMC) are the cells most frequently employed in human biomonitoring studies using the challenge-comet assay, but having a validated alternative of non-invasive biomatrix would be highly convenient for certain population groups and circumstances. The objective of this study was to validate the use of salivary leucocytes in the challenge-comet assay. Leucocytes were isolated from saliva samples and challenged (either in fresh or after cryopreservation) with three genotoxic agents acting by different action mechanisms: bleomycin, methyl methanesulfonate, and ultraviolet radiation. Comet assay was performed just after treatment and at other three additional time points, in order to study repair kinetics. The results obtained demonstrated that saliva leucocytes were as suitable as PBMC for assessing DNA damage of different nature that was efficiently repaired over the evaluated time points, even after 5 months of cryopreservation (after a 24 h stimulation with PHA). Furthermore, a new parameter to determine the efficacy of the repair process, independent of the initial amount of damage induced, is proposed, and recommendations to perform the challenge-comet assay with salivary leucocytes depending on the type of DNA repair to be assessed are suggested. Validation studies are needed to verify whether the method is reproducible and results reliable and comparable among laboratories and studies.

Low-volume cycling training improves body composition and functionality in older people with multimorbidity: a randomized controlled trial.

Physical exercise, when practiced regularly and in adequate doses, is a proven nonpharmacological measure that helps to prevent and reverse noncommunicable diseases, as well as reduce mortality rates from any cause. In general, older adults perform insufficient physical activity and do not meet the doses recommended by the World Health Organization for the improvement of health through physical activity. However, there is little evidence on adequate doses of exercise in older people, especially in those with multimorbidity. Our main aim was to evaluate the effect of a 6-week intervention on health-related outcomes (body composition, hemodynamic and functionality changes) in 24 individuals aged 65 and older with multimorbidity in a randomized controlled trial. The intervention consisted of a very low volume (60 min per week) of low-to-moderate intensity exercise training (perception of effort from 3 to 6 on an 11-point scale). After the intervention, blood pressure was significantly (p = 0.038) reduced in the exercise group (EG), with a higher reduction in men. Furthermore, the EG decreased their waist circumference (p = 0.005), a proxy of abdominal adiposity, and demonstrated an increased likelihood (73%) that a randomly selected change in muscle mass score from the EG would be greater than a randomly selected change score from the control group. The exercise intervention was particularly effective in enhancing the functionality of older adults with multimorbidity, especially in walking speed and balance skills. Perceptually regulated intensity during exercise training seemed to be a very interesting strategy to train individuals with low physical fitness and comorbidities. This study is registered with Clinicaltrials.gov (NCT04842396).

Bright Light Therapy in Older Adults with Moderate to Very Severe Dementia: Immediate Effects on Behavior, Mood, and Physiological Parameters.

Bright light therapy (BLT) has demonstrated positive short- and long-term effects in people with cognitive impairment or dementia; however, the immediate impact of BLT sessions has been scarcely investigated. In this study, we aimed to explore the immediate effects of BLT on behavior, mood, and physiological parameters (oxygen saturation/heart rate) in a sample of institutionalized older adults with moderate to very severe dementia, with a median age of 85.0 (interquartile range, IQR, 82.0-90.0), being higher in men (87.0 years, IQR 80.0-94.0) than in women (84.5 years, IQR 82.0-89.5). The BLT protocol consisted of 30-min morning sessions of 10,000 lux, Monday through Friday, for 4 weeks. The physiological parameters were recorded immediately before and after each session by pulse oximetry. Mood and behavior were assessed before, after, and during the sessions using the Interact scale. Post-session Interact scores showed a significant decrease in the items Tearful/sad and Talked spontaneously, and a significant increase in the items Enjoying self, active or alert, and Relaxed, content or sleeping appropriately. Interact scores during the sessions reflected a significant decrease in the speech-related items. Both physiological parameters changed positively from before to after sessions. Our results suggest that BLT provides immediate positive effects on mood, stimulation level, and physiological parameters, as well as a trend toward decreased speech. More robust research is needed to further explore the immediate impact of BLT. This study is registered with Clinicaltrials.gov (NCT04949984).