Associations between physical and cognitive activities and olfactory function in older adults

Olfactory function improves following hemodialysis

Studies suggest that regular physical activity can help maintain and enhance brain functions in older adults. However, we still do not understand how physical activity impacts the rate of cognitive decline. One major issue is whether physical activity broadly defined (i.e., activity that is part of one's daily life involving bodily movements and the use of skeletal muscles) or structured exercise (i.e., physical activity that is planned, structured, and purposive to improve physical fitness) leads to the same benefits in preventing age-related cognitive decline. More studies are needed to appreciate the level of change or protection provided by physical activity, the basic mechanisms by which this change occurs, and whether physical activity can be beneficial despite chronic medical conditions and neurological or geriatric syndromes. This special issue presents original research results that bring additional support to the notion that physical exercise is an efficient nonpharmaceutical approach that can be used to enhance and maintain cognitive functions in healthy older adults and patients suffering from mild cognitive impairment. In a paper, we propose a brief review of the main impacts of exercise on cognition in older adults, frail patients, and those with mild cognitive impairment and dementia. Another paper of this special issue brings important knowledge in this regard. L. S. Nagamatsu et al. showed that physical activity helps improve verbal and spatial memory in older adults with probable mild cognitive impairment. In this study, eighty-six women aged 70–80 years with subjective memory complaints completed one of three interventions for 6 months: resistance training, aerobic training, or balance and tone (control). Both exercise groups showed significant improvements in memory performance, which was not observed in controls. An original study of this special issue explored the benefits of swimming on cognition in older adults. A. Abou-Dest et al. compared three groups of sixteen volunteer participants (young adults, sedentary older adults, and older adults who regularly practice swimming) on a battery of cognitive tasks. They reported that in older adults, regular swimming was related to better performance on executive functions but not on information processing speed. The selective benefit of exercise on executive control tasks was also reported after only 3 months of exercise intervention in a study of this special issue by D. Predovan et al. compared to controls, the training group showed significant improvements in physical capacity and enhanced Stroop performance, but only in the inhibition/switching condition, and the increase in aerobic capacity induced by the training regimen correlated negatively with reaction time in the inhibition/switching condition of the Stroop task at posttest. Importantly, the reported gains in cognitive performance were observed after only three months of physical training. The complex interaction between bodily exercise and cognition also calls into question the impact that mobility and gait might have on cognition in older adults. P. Plummer-D'Amato et al. addressed this issue in a contribution to this special issue. Studying how gait difficulty and cognitive task difficulty impact cognitive-motor interference in aging, they showed that gait task difficulty influences dual-task effects on gait speed, especially in older adults, and that this effect is influenced by the difficulty of the cognitive task. Another paper of the special issue brings up important issues on the potential moderators of physical activity on brain functions. R. L. Leckie et al. demonstrated how genes (APOE, BDNF, and COMT) along with dietary omega-3 fatty acid and docosahexaenoic acid (DHA) are potential moderators of the effect of physical activity on brain health. R. L. Leckie et al.'s proposal calls for further studies on the role of genes and dietary factors in the relationship between physical exercise and cognitive functions in older adults populations. All together, the studies published in this special issue bring additional scientific support to the notion that physical activity and exercise are a promising approach to alleviate the age-related impact on the body and mind. By doing so, they also support the promotion of health policies that should target inactivity in individuals of all ages and with any medical condition who are able to safely participate in physical activity.

Among older adults, both olfaction and motor function predict future cognitive decline and dementia, suggesting potential shared causal pathways. However, it is not known whether olfactory and motor function are independently related in late life. We assessed cross-sectional associations of olfaction with motor and cognitive function, using concurrent data on olfactory function, mobility, balance, fine motor function, manual dexterity, and cognition in 163 Baltimore Longitudinal Study of Aging participants aged 60 and older without common neurological diseases (n = 114 with available cognitive data). Using multiple linear regression, we adjusted for age, sex, race, smoking history, height, and weight for mobility and balance, and education for cognition. We used multiple linear regression to test whether olfaction-motor associations were independent of cognition and depressive symptoms. Olfactory scores were significantly associated with mobility (usual gait speed, rapid gait speed, 400-m walk time, and Health ABC Physical Performance Battery score), balance, fine motor function, and manual dexterity (all p < .05). In those with available cognitive data, additional adjustment for depressive symptoms, verbal memory, or visuoperceptual speed demonstrated especially strong independent relationships with challenging motor tasks such as 400-m walk and nondominant hand manual dexterity (p < .005). This study demonstrates for the first time that, in older adults, olfactory function is associated with mobility, balance, fine motor function, and manual dexterity, and independent of cognitive function, with challenging upper and lower extremity motor function tasks. Longitudinal studies are needed to determine if olfactory performance predicts future mobility and functional decline.

ObjectivePatients with autoimmune diseases often present with olfactory impairment. The aim of the study was to assess the olfactory functions of patients with primary Sjögren’s syndrome and to correlate these findings with their disease activity.MethodsFifty-two patients with primary SS and 52 sex- and age-matched healthy control subjects were included. All of them underwent clinical and laboratory examination. Olfactory functions were evaluated using olfactory function assessment by computerized testing including the three stages of smell: threshold, identification, and memory of the different odors.ResultsAll the olfactory scores (olfactory threshold, identification, and memory) in patients with pSS were significantly decreased than the control group (all P < 0.01). Patients had higher proportion of anosmia (13.5% vs 0%) and hyposmia (19.2% vs 11.5%) than controls (χ2 = 10.526, P < 0.01). Multivariable regression analysis revealed that ESSDAI and the symptoms of dryness, fatigue, and limb pain had negative influence on olfactory function (adjusted R2 = 0.381, 0.387, 0.513, and 0.614, respectively). ESSPRI showed significantly negative association with olfactory threshold, identification, memory, and total scores. Olfactory identification and memory scores were decreased in pSS patients with thyroid dysfunction or hypocomplementemia (P < 0.05). Smell threshold scores were decreased in pSS patients with anti-SSA antibody or anti-nuclear antibody compared with those without those autoantibodies (P < 0.01).ConclusionOur findings indicate that olfactory functions are impaired in pSS patients. There was a close correlation between olfactory dysfunction and disease severity and immunological abnormalities. Immune and systemic inflammation dysregulation might play a role in the mechanism of this defect.

With the arrival of an aging society, cognitive health in older adults has become a global focal point. Cross-sectional studies have shown that internet use and physical activity may significantly affect cognitive function in older adults, but their longitudinal relationships and underlying mechanisms have not been fully explored. This study aims to explore the relationship between internet use, physical activity, and cognitive function, and examine the mediating role of physical activity. This study uses two rounds of longitudinal data from the China Health and Retirement Longitudinal Study (2018 and 2020), including a total of 2,383 individuals aged 60 and above. Cross-lagged regression analysis is used to test the bidirectional relationship between internet use and cognitive function, while a semi-longitudinal mediation model is used to examine the mediating role of physical activity. The results indicate that there is a bidirectional relationship between internet use, physical activity levels, and cognitive function. Higher levels of internet use are associated with better cognitive function, and physical activity levels mediate the longitudinal relationship between internet use and cognitive function in older adults. This study reveals the complex relationship between cognitive function, internet use, and physical activity in older adults, and provides new perspectives for interventions aimed at improving cognitive health in older adults. Future research should further explore the dynamic changes between these variables to develop more effective intervention strategies and improve cognitive health and well-being in older adults.

ABSTRACTObjectivesInvestigate whether engaging in cognitive and physical activity is associated with cognitive performance and gray matter volume. Specifically, this study investigated the role of both activity types performed in close temporal proximity to each other.MethodsCognitively healthy older adults (n = 155; 73–78 years; 45% female) enrolled in the PATH Through Life study with valid cognitive, MRI and physical activity (PA) measures were included in the study. PA was objectively measured with a SenseWear Armband for 7 days. PA and cognitive engagement were self‐reported through a 1‐week activity diary. The number of 3‐h periods in which ≥ 15 min of objective moderately vigorous physical activity (MVPA) > 3METs, cognitive activity, or both occurred, were assessed. Cognitive game activity periods were also coded. Associations between activity engagement and outcome measures were assessed with hierarchical regression models while controlling for age, sex, and education.ResultsFor cognitive engagement, greater activity diversity was associated with better symbol digits modalities test performance (SDMT), while a greater number of cognitive activity periods were associated with better SDMT, and digit span backward performance. Greater cognitive game periods improved model fit for several cognitive outcomes and right hippocampal volume. MVPA periods were not associated with any outcome. The number of periods in which cognitive activity and MVPA were present together was associated with better immediate recall. Periods in which cognitive games and MVPA co‐existed were associated with cognitive and volumetric outcomes.DiscussionThese findings support the notion that both cognitive and physical activity are positively related to brain health. They highlight the potential importance of performing both activity types in close temporal proximity to support the aging brain.

High vitamin D and physical activity (PA) levels are independently associated with improved body composition and muscle function in older adults. The objective of this study was to investigate the interaction of 25-hydroxyvitamin D (25OHD) and PA status in maintenance of body composition and muscle function in older adults. This was a 5-year prospective population-based study of Australian community-dwelling older adults. Participants in the study included 615 community-dwelling volunteers aged 50 years old or older [61.4 ± 6.9 (mean ± SD) y; 48% female] randomly selected from electoral rolls and categorized according to baseline serum 25OHD (≥ or <50 nmol/L) and PA (≥ or <10,000 pedometer determined steps/d) levels as follows: high 25OHD and high PA (VitD+PA+); high 25OHD and low PA (VitD+PA-); low 25OHD and high PA (VitD-PA+); and low 25OHD and low PA (VitD-PA-). A subset of 518 participants completed accelerometer assessments during follow-up. Changes in dual-energy X-ray absorptiometry-assessed body composition and lower-limb muscle function were measured. VitD+PA+ had significantly smaller increases in body fat over 5 years compared with other groups (all P < .05). Higher baseline pedometer-determined PA resulted in declines in total body fat (β = -.23 kg per 100 steps/d, P = .001) over 5 years for participants with high 25OHD but not those with low 25OHD (P > .05). Among participants with accelerometer data, these associations were generally mediated by higher levels of moderate/vigorous PA. High vitamin D status appears to enhance PA-related declines in body fat during aging, but the mechanism may be greater amounts of outdoor moderate/vigorous PA rather than a direct effect of 25OHD.

The effect of a multicomponent intervention to promote community activity on cognitive function in older adults with mild cognitive impairment: A randomized controlled trial

Physical activity is associated with improved health and function in older adults, yet most older adults are sedentary. Loneliness is associated with decreased physical activity at the cross-section, but longitudinal studies are scarce. We examined longitudinal associations between loneliness and physical activity-and whether they were modified by marital status and network size (the number of children, relatives, and friends a person interacts with at least once a month). We analyzed data from 1,931 older adults without dementia at baseline from the Rush Memory and Aging Project with a mean follow-up of 4.8 years (mean age 79.6 ± 7.7, 74.9% women). Loneliness was assessed using the de Jong Gierveld Loneliness Scale. Physical activity was assessed as the frequency with which participants engaged in five categories of activities (e.g., walking, gardening, calisthenics, bicycling, and swimming). Linear mixed effects models examined associations between baseline loneliness and change in physical activity over time after adjusting for demographics, depressive symptoms, global cognition, disability, network size, marital status, social support, and social and cognitive activities. We assessed for effect modification by marital status and network size. Associations between loneliness and physical activity differed by marital status. In widowed individuals, baseline loneliness was associated with a 0.06 h/week greater decrease in physical activity per year compared to those who were not lonely (p = 0.005, CI -0.1, 0.02)-which equaled a 150% decrease in physical activity per year. Loneliness did not predict a statistically significant decrease in physical activity in married or unmarried individuals. Loneliness is associated with decreased physical activity in widowed older adults and should be considered in the design of interventions to prevent or slow the decline in physical activity and promote healthy aging.

Objective: This cross-sectional study evaluates the impact of active or non-active lifestyle in terms of physical, cognitive and social activity on the olfactory function in Elderly Subjects (ES) and aims at looking for a correlation between the time devoted to life activities and the score obtained during the olfactory tests by each individual.Methods: One hundred and twenty-two elderly volunteers were recruited in Sardinia (Italy) and divided into active ES (n = 60; 17 men, 43 women; age 67.8 ± 1.12 years) and inactive ES (n = 62; 21 men, 41 women, age 71.1 ± 1.14 years) based on their daily physical activities. The olfactory function was evaluated using the “Sniffin’s Sticks” battery test, while the assessment of daily activities was made by means of personal interviews.Results: A significant effect of active or inactive lifestyle was found on the olfactory function of ES (F(1,120) > 10.16; p < 0.005). A positive correlation was found between the olfactory scores and the number of hours per week dedicated to physical activities (Pearson’s r > 0.32, p ≤ 0.014) in both active and inactive ES.Conclusions: High levels of exercise and non-exercise physical activity are strongly associated with the olfactory function and, consequently, with the quality of life of the elderly. Given the limited physical exercise of elderly people, they can benefit from a more active lifestyle by increasing non-exercise physical activities.

Background: The world is experiencing widespread population ageing with the proportion of people aged 60 years and over growing faster than any other age group (WHO, 2002). This demographic trend creates significant social and economic challenges to policy makers and has resulted in research imperatives to keep older adults independent in the community for as long as possible. Ageing is associated with cognitive disorders and neurodegenerative conditions (Keller, 2006; Bishop, Lu & Yankner, 2010). However, there is significant heterogeneity in this process, with different individuals experiencing varying degrees of age related declines (Christensen et al., 1999; Salthouse, 2004). This has resulted in research efforts to uncover modifiable factors that may attenuate cognitive and emotional decline and promote the successful ageing of older adults. The concept of activity underpinning successful ageing pervades current frameworks and models of health and wellbeing (WHO, 2002; Rowe & Kahn, 1997). Activity participation is central to the enhancement of functioning, health and the protection of disability as individual’s age and forms the basis for the current research. Study Aims: The primary aim of this study is to explore the relationship between activity types (i.e. cognitive, physical and social activity) and emotional and cognitive functioning in a large community based sample of women. A secondary aim is to investigate the relationship between age, education and perceived health on activity levels and cognitive and emotional functioning within this sample. Method: The participants were 357 randomly selected community dwelling women aged 40 to 79 years who participated in the Longitudinal Study of Women (LAW) at the Betty Byrne Henderson Women’s Health Research Centre within the Royal Brisbane and Women’s Hospital, Australia. Participants completed self-report questionnaires and underwent a detailed neuropsychological assessment of their executive functioning and memory. Results: Participation in cognitive activities predicted better cognitive functioning but physical and social activities did not significantly predict improved cognitive functioning after taking into account an individual’s participation in cognitive activities. Greater participation in social and physical activities were related to lower levels of depression but were unrelated to levels of anxiety. While participation in cognitive activities did not uniquely predict emotional functioning after taking into account an individual’s participation in social and physical activities. The findings also revealed that as people aged their participation in cognitive and physical activities declined, while their participation in social activities remained the same. Higher education levels were related to increased participation in cognitive and physical activities but not social activity. Better perceived health status was related to higher participation in social and physical activity but not cognitive activities. Conclusion: Different types of activities had varying relationships with cognitive and emotional functioning. The clinical implications of these results is that public health programs designed to optimise the wellbeing and successful ageing of adults should potentially advocate not only activity participation but stress the need for a repertoire of cognitive, social and physical activities to maximise the differential benefits that participation appears to exert on cognitive and emotional health. The findings also highlight risk factors for inactivity such as increasing age, lower perceived health and lower education levels. This will be particularly pertinent for cognitive and physical activities which are associated with declining participation rates as people age.

ObjectiveEngaging in physical activity (PA) and/or cognitive activity (CA) retains function in older adults, but whether the combination of these activities is associated with disability onset is still unknown. This study aimed to examine the prospective association of PA and/or CA with disability onset in older adults.MethodsThis was an ongoing prospective community-based cohort study. Data collection was conducted through a health check. An analyzable sample of 2668 participants (mean age = 75.5 years; 51.6% female) were categorized into 4 groups based on quartile 1 (low) and 2 to 4 (high) values of accelerometer-measured moderate-to-vigorous PA and CA scale scores based on the frequency of 6 activities including reading, writing for pleasure, doing crossword puzzles, and playing board games or cards. Disability onset was monitored through long-term care insurance certification for at least 2 years.ResultsA log-rank test showed significantly lower incidence of disability in the high PA and low CA group and the high PA and high CA group compared with the low PA and low CA group. Cox-proportional hazards models (referring to the low PA and low CA group) showed that only the high PA and high CA group was significantly associated with a lowered hazard ratio for disability onset (0.51; 95% CI = 0.29–0.90) after adjusting for covariates.ConclusionsEngaging in both PA and CA is effective for reducing risk of disability onset, but engaging in either PA or CA is not effective.ImpactPhysical therapists can be guided by this research to design intervention strategies for people at risk of disability.

Background Population aging is a significant trend in China's development, and the decline in lower limb function in older adults is one of the primary health threats, often leading to falls or injuries. Several studies have applied motor imagery (MI) to improve lower limb function in older adults. However, the benefits of this intervention method for older adults remain to be further explored. Objective This paper systematically reviews the benefits of motor imagery in improving lower limb function in older adults using the International Classification of Functioning, Disability, and Health (ICF) framework. Methods Relevant literature on motor imagery interventions targeting balance ability in healthy older adults was retrieved from four English and three Chinese databases. The content of the literature was analyzed and coded based on the theoretical framework of the ICF. Results A total of 11 studies from 7 countries were included, comprising 11 randomized controlled trials (RCTs) with 758 older adult participants. Interventions included MI alone or combined with physical exercise, and intervention settings encompassed laboratories, communities, hospitals, and homes. Outcome measures included motor function, postural changes and maintenance, gait, and mobility. Conclusion Motor imagery interventions and their combination with other intervention methods can improve lower limb function and related motor abilities in older adults. However, compared to MI alone, the effects of combined MI interventions on lower limb function in older adults remain inconclusive.

Lifestyle factors such as participation in cognitively stimulating activities and physical activity are hypothesized to foster neural connections and enhance resilience, thereby attenuating cognitive loss in the context of Alzheimer’s disease (AD) and other neurodegenerative diseases. Nonetheless, the relationship between these factors and important clinical outcomes of cognition and brain atrophy is not well understood. We assessed cognitive and physical activity levels in a large, tertiary memory clinic cohort with various clinical and aetiological diagnoses. Furthermore, we investigated whether cognitive and physical activities relate to resilience against brain atrophy across the AD continuum. In the memory clinic-based Amsterdam Dementia Cohort (ADC), 4033 individuals completed the self-reported questionnaires to quantify their engagement in cognitive (lifetime, past and current) and physical (current) activities. Firstly, we examined differences in activity scores across diagnostic groups [i.e. Alzheimer’s and non-Alzheimer’s types of dementia, mild cognitive impairment (MCI) and subjective cognitive decline (SCD)] using linear models adjusted for age and sex. Secondly, in a subset on the AD continuum (i.e. amyloid-β-positive with SCD, MCI or Alzheimer’s dementia; n = 904), we used linear mixed-effects models adjusted for age and sex to assess whether cognitive and physical activities had an interactive or additive effect on concurrent cognition and rate of decline (global cognition, memory and executive functioning) at a given level of magnetic resonance imaging-based temporoparietal brain atrophy. We also tested associations with clinical progression and with mortality using Cox survival models. Lifetime and current cognitive activity, and current physical activity were generally lower in more cognitively unimpaired groups (all P < 0.001), while differences in past cognitive activity between diagnostic groups were not significant (P = 0.08). Within the AD continuum, at similar levels of temporoparietal atrophy, higher cognitive and physical activities were associated with better cognition at baseline (past cognitive activity: βStd = 0.15–18, PFDR < 0.001; and physical activity: βStd = 0.9–0.11, PFDR < 0.05). In longitudinal analyses, neither factor was related to cognitive decline nor clinical progression. Current cognitive activity [hazard ratio (HR) = 0.82 (0.73–0.92), PFDR < 0.001] and physical activity [HR = 0.88 (0.79–0.99), PFDR < 0.05] were associated with reduced mortality risk in the total sample, while past cognitive activity was linked to reduced mortality only in MCI [HR = 0.54 (0.36–0.8), PFDR < 0.01]. While associations between current cognitive and physical activities with better concurrent cognitive performance might be (partially) explained by reverse causality, the observed effects of past cognitive activity suggest that early and mid-life participation in cognitively stimulating activities may provide a cognitive benefit once AD manifests.

Advanced aging is associated with cognitive decline. To decrease the healthcare system and socio-economic burdens as well as to promote better quality of life, is important to uncover the factors that may be related to the delay of cognitive impairments in older adults. This study investigated the relationship between physical activity levels, sedentary behavior and cardiorespiratory fitness with cognitive functioning in healthy older adults. Furthermore, it examined the mediating role of processing speed on the association between physical activity and executive functions and long-term memory. Thirty-two individuals aged between 63 and 77 years (M = 68.16, SD = 3.73) underwent measurements of maximal oxygen uptake (VO2peak), 1-week of PA accelerometer measurement and a comprehensive cognitive assessment. Significant associations were observed between MVPA and cognitive processing speed. Equally, a significant positive indirect effect of MVPA on executive functioning and long-term memory was mediated by processing speed. Also, MVPA levels differentiated cognitive functioning in older adults – the physical active group outperformed the physical inactive group in processing speed, executive functions, and language abilities. Our results contribute to the literature on the MVPA levels as an important tool to promote healthier cognitive aging.