Function In Old Age Research Articles

ADULT-LIFE OCCUPATIONAL EXPOSURES: ENRICHED ENVIRONMENT OR A STRESSOR FOR THE AGING BRAIN?

The positive association between midlife occupational complexity and cognitive functioning in older age is well documented. Much less is known about the underlying neural mechanisms and whether occupational stress may accelerate neurocognitive aging. According to the BOSS model (Brain aging: Occupational Stimulation and Stress), occupational exposures may serve as long-term protective and risk factors that influence the rate and extent of neurocognitive decline in aging (Burzynska, Jiao & Ganster 2018). We present findings from three independent samples linking different occupational exposures (e.g. work physical demands, innovation, autonomy, employer control) with brain volume in cognitively healthy older adults. We discuss the findings in the context of cognitive reserve and brain maintenance. Our findings suggest that occupational activities need to be acknowledged as an important factor in lifespan cognitive and brain development and warrant further research, with a possible outcome of workplace interventions aimed at optimizing neurocognitive aging.

Psychosocial and Health-Related Factors Associated With Discordance Between 13-Year Trajectories of Self-Reported Functional Limitations and Performance-Based Physical Functioning in Old Age.

Objective: The objective of this study was to examine correlates of discordance between 13-year trajectories of self-reported functional limitations and performance-based physical functioning in older adults. Method: We included 2,135 participants from the population-based Longitudinal Aging Study Amsterdam, the Netherlands, followed across 1995-2008. Self-reported functional limitations included six (instrumental) activities of daily living. Performance-based functioning was a composite of four tests. We used latent class growth analysis and multinomial logistic regression to examine discordance and its correlates. Results: Patterns of discordance and concordance (41% concordance, 46% “overestimation” of daily functioning, 13% “underestimation”) appeared to be persistent over 13 years. Older age, male sex, cognitive impairment, absence of pain, and light alcohol use were associated with overestimation. Younger age, female sex, and lower self-rated health were associated with underestimation. Discussion: Factors associated with overestimation partly differ from those associated with underestimation. Factors that are highly stable over time are particularly good indicators of persistent discordance.

Evidence for Maintained Post-Encoding Memory Consolidation Across the Adult Lifespan Revealed by Network Complexity

Memory consolidation is well known to occur during sleep, but might start immediately after encoding new information while awake. While consolidation processes are important across the lifespan, they may be even more important to maintain memory functioning in old age. We tested whether a novel measure of information processing known as network complexity might be sensitive to post-encoding consolidation mechanisms in a sample of young, middle-aged, and older adults. Network complexity was calculated by assessing the irregularity of brain signals within a network over time using multiscale entropy. To capture post-encoding mechanisms, network complexity was estimated using functional magnetic resonance imaging (fMRI) during rest before and after encoding of picture pairs, and subtracted between the two rest periods. Participants received a five-alternative-choice memory test to assess associative memory performance. Results indicated that aging was associated with an increase in network complexity from pre- to post-encoding in the default mode network (DMN). Increases in network complexity in the DMN also were associated with better subsequent memory across all age groups. These findings suggest that network complexity is sensitive to post-encoding consolidation mechanisms that enhance memory performance. These post-encoding mechanisms may represent a pathway to support memory performance in the face of overall memory declines.

Does community social capital buffer the relationship between educational disadvantage and cognitive impairment? A multilevel analysis in Japan

BackgroundThis study explored the relationship between community social capital and cognitive impairment, with a focus on the buffering role of community social capital in the association between educational disadvantage and cognitive impairment in community-dwelling older adults in Japan.MethodsWe used data from two population-based, cross-sectional surveys targeting people aged ≥65 years in a suburban city of the Tokyo metropolitan area (n = 897; 49.8% men; average age = 74.4 years). Social capital included social support (emotional and instrumental support) and the strength of social networks (neighborly ties). To create district-level social capital indicators, we aggregated individual responses on social capital within each district. The Mini-Mental State Examination, Japanese version was used for the assessment of cognitive function.ResultsUsing multilevel logistic regression analysis, we found that lower amounts of district-level emotional and instrumental support were associated with a greater likelihood of cognitive impairment among men. For women, district-level emotional support was associated with a greater likelihood of cognitive impairment. Additionally, a strong district-level social network buffered the relationship between low education and cognitive impairment in both sexes.ConclusionsCommunity social capital appears to have a protective role in determining cognitive function in old age. Our findings may facilitate the development of new community-based strategies to combat dementia.

An investigation into early-life stress and cognitive function in older age.

Early-life stress (ELS) has previously been identified as a risk factor for cognitive decline, but this work has predominantly focused on clinical groups and indexed traditional cognitive domains. It, therefore, remains unclear whether ELS is related to cognitive function in healthy community-dwelling older adults, as well as whether any effects of ELS also extend to social cognition. To test each of these questions, the Childhood Trauma Questionnaire (CTQ) was administered to 484 older adults along with a comprehensive neuropsychological test battery and a well-validated test of social cognitive function. The results revealed no differences in global cognition according to overall experiences of ELS. However, a closer examination into the different ELS subscales showed that global cognition was poorer in those who had experienced physical neglect (relative to those who had not). Social cognitive function did not differ according to experiences to ELS. These results indicate that the relationship between ELS and cognition in older age may be dependent on the nature of the trauma experienced.

Exercise Snacking to Improve Muscle Function in Healthy Older Adults: A Pilot Study.

Loss of muscle mass and strength are seemingly accepted as part of the ageing process, despite ultimately leading to the loss of independence. Resistance exercise is considered to be primary defence against loss of muscle function in older age, but it typically requires access to exercise equipment often in a gym environment. This pilot study aimed at examining the effect of a 28-day, unsupervised home-based exercise intervention on indices of leg strength and muscle size in healthy older adults. Twenty participants were randomly assigned to either maintain their habitual physical activity levels (Control; n=10; age, 74 (5) years; body mass, 26.3 (3.5) kg/m2) or undertake “exercise snacks” twice daily (ES; n=10; age, 70 (4) years; body mass, 25.0 (3.4) kg/m2). Both groups consumed 150 g of yogurt at their breakfast meal for the duration of the intervention. Sixty-second sit-to-stand score improved by 31% in ES, with no change in Control (p < 0.01). Large effect sizes were observed for the difference in change scores between the groups for interpolated maximum leg pressing power (6% increase in ES) and thigh muscle cross-sectional area (2% increase in ES). The present pilot data suggest that exercise snacking might be a promising strategy to improve leg muscle function and size in older adults and that further investigation into zero-cost exercise strategies that allow high frequency of training is warranted.

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

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

Associations of accelerometer-based sleep duration and self-reported sleep difficulties with cognitive function in late mid-life: the Finnish Retirement and Aging Study

ObjectivesPrior evidence suggests that sleep duration and sleep difficulties may be associated with cognitive function in old age, but little is known about the sleep–cognition association in late mid-life. Our aim was to examine the associations of accelerometer-based sleep duration as well as subjective sleep difficulties with different domains of cognitive function among aging workers. MethodsThe study population consisted of 289 participants (mean age 62.4 years, SD 1.02; 83% women) from the Finnish Retirement and Aging Study (FIREA). Sleep difficulties were measured using Jenkins Sleep Problem Scale (difficulties falling asleep, difficulties maintaining sleep, waking up too early in the morning, and nonrestorative sleep). Sleep duration was measured with wrist-worn accelerometer and self-report, and participants were divided into short (<7 h/night), mid-range (7–9 h/night) and long (≥9 h/night) sleepers. Participants underwent extensive cognitive testing covering three domains: (1) memory, (2) executive function, and (3) attention and information processing. ResultsGreater difficulties in waking up too early in the morning were associated with poorer executive function measured with Spatial Working Memory (SWM) test (p = 0.005). Additionally, nonrestorative sleep was associated with poorer executive function measured with Trail Making Test, B–A, (p = 0.036) and borderline significantly with lower SWM (p = 0.056). Compared to mid-range sleepers, long sleepers tended to have poorer cognitive function (all memory function tests and SWM), but the associations were not statistically significant due to small number of long sleepers. ConclusionsSubjective sleep difficulties may be linked to poorer executive function in a relatively healthy population of older workers in their 60 s. Thus, promoting good sleep quality may translate into better cognitive health in late mid-life.

Lifestyle and brain function in old age: Influence of physical and instrumental activities

Lifestyle and brain function in old age: Influence of physical and instrumental activities

Colonic Motility and Jejunal Vagal Afferent Firing Rates Are Decreased in Aged Adult Male Mice and Can Be Restored by an Aminosterol

There is a general decline in gastrointestinal function in old age including decreased intestinal motility, sensory signaling, and afferent sensitivity. There is also increased prevalence of significant constipation in aged populations. We hypothesized this may be linked to reduced colonic motility and alterations in vagal-gut-brain sensory signaling. Using in vitro preparations from young (3 months) and old (18–24 months) male CD1 mice we report functional age-related differences in colonic motility and jejunal mesenteric afferent firing. Furthermore, we tested the effect of the aminosterol squalamine on colonic motility and jejunal vagal firing rate. Old mice had significantly reduced velocity of colonic migrating motor complexes (MMC) by 27% compared to young mice (p = 0.0161). Intraluminal squalamine increased colonic MMC velocity by 31% in old mice (p = 0.0150), which also had significantly reduced mesenteric afferent single-unit firing rates from the jejunum by 51% (p < 0.0001). The jejunal vagal afferent firing rate was reduced in aged mice by 62% (p = 0.0004). While the time to peak response to squalamine was longer in old mice compared to young mice (18.82 ± 1.37 min vs. 12.95 ± 0.99 min; p = 0.0182), it significantly increased vagal afferent firing rate by 36 and 56% in young and old mice, respectively (p = 0.0006, p = 0.0013). Our results show for the first time that the jejunal vagal afferent firing rate is reduced in aged-mice. They also suggest that there is translational potential for the therapeutic use of squalamine in the treatment of age-related constipation and dysmotility.

Longitudinal associations between hearing loss and general cognitive ability: The Lothian Birth Cohort 1936.

Hearing impairment is associated with poorer cognitive function in later life. We tested for the potential contribution of childhood cognitive ability to this relationship. Childhood cognitive ability is strongly related to cognitive function in older age, and may be related to auditory function through its association with hearing impairment risk factors. Using data from the Lothian Birth Cohort, 1936, we tested whether childhood cognitive ability predicted later-life hearing ability then whether this association was mediated by demographic or health differences. We found that childhood cognitive ability was negatively associated with hearing impairment risk at age 76 (odds ratio = .834, p = .042). However, this association was nonsignificant after subsequent adjustment for potentially mediating demographic and health factors. Next, we tested whether associations observed in older age between hearing impairment and general cognitive ability level or change were accounted for by childhood cognitive ability. At age 76, in the minimally adjusted model, hearing impairment was associated with poorer general cognitive ability level (β = −.119, p = .030) but was not related to decline in general cognitive ability. The former association became nonsignificant after additional adjustment for childhood cognitive ability (β = −.068, p = .426) suggesting that childhood cognitive ability contributes (potentially via demographic and health differences) to the association between levels of hearing and cognitive function in older age. Further work is needed to test whether early life cognitive ability also contributes to the association (documented in previous studies) between older-age hearing impairment and cognitive decline.

Meta-inflammaging at the crossroad of geroscience.

Geroscience posits that selected fundamental biological processes are the foundation of age‐related chronic diseases and are responsible for the decline in physical and mental function in old age. Late‐life chronic low‐grade inflammation (“inflammaging”) and altered signal transduction pathways in metabolism have been identified as two of the key themes in the aging process. Age‐related changes in the immune and metabolic responses are also recognized as playing a critical pathogenic role in most common chronic medical conditions that plague the elderly. Emerging investigations emphasize the interconnectedness of the immune and metabolic responses in aging, an area of gerontological research that can be termed “meta‐inflammaging.”

Technology, Physical Activity, Loneliness, and Cognitive Functioning in Old Age

Abstract. Information and communication technology (ICT) has the potential to benefit aging processes. This study examined portable ICT usage and associated changes in physical activity, loneliness, and cognitive functioning. Ninety-two mostly-novice tablet-users aged 51–85 years participated in technology workshops and then reported on their portable ICT use biweekly for 6+ months. Physical activity, loneliness, and executive functioning were assessed before and after this period. More frequent use of exercise functions was associated with more moderate-intensity physical activity and less sitting, controlling for pretracking levels. More frequent use of social functions was associated with more social loneliness and a tendency toward less emotional loneliness, controlling for pretracking levels of loneliness. The use of exercise and social functions showed no associations with executive functioning. Portable ICT thus may bring both risks and benefits for physical and social functioning in older adulthood.

Impact of hearing loss in the lives of geriatric individuals

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; Hearing loss in old age is a vexing problem and millions of people worldwide are suffering from it. The aim of this study is to identify the problems which geriatric individuals with hearing loss experience and to help them to overcome their disability and its effects on social engagement and interpersonal relationship.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; The study was conducted in a tertiary care hospital and is based on prospective study. The data collection was done in the form of confrontational interview. &lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results:&lt;/strong&gt; According to our study individuals suffering from moderate hearing loss have difficulty in communicating with friends, relatives and even strangers. They even face problems in travelling. They feel disoriented during conversation and tend to miss out parts of conversation. They tend to use their visual signals more than hearing for example while watching television they try to focus and interpret more by the video than by listening to the audio. People suffering from mild to moderate hearing loss try to ignore the disability and request people to repeat statements but inadvertently still miss out the conversation and the try to ignore the handicap.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; Age related hearing loss known as presbycusis and it is one of the most prevalent conditions in old age and millions of people worldwide are afflicted. It is one of the leading cause of overall diminution of physical and mental performance in old age. It is often neglected and remains undetected for long in geriatric population due to gradual progression.&lt;/p&gt;

Midlife Cardiovascular Status and Old Age Physical Functioning Trajectories in Older Businessmen.

The associations between cardiovascular disease (CVD) risk and later physical functioning have been observed, but only a few studies with follow-up into old age are available. We investigated the association between cardiovascular status in midlife and physical functioning trajectories in old age. Prospective cohort study. Helsinki Businessmen Study. We studied white men born between 1919 and 1934 in the Helsinki Businessmen Study (HBS, initial n = 3490). Three CVD status groups were formed based on clinical measurements carried out in 1974: signs of CVD (diagnosed clinically or with changes in ECG, chronic disease present or used medication, n = 563); healthy and low CVD risk (n = 593) and high CVD risk (n = 1222). Of them, 1560 men had data on physical functioning from at least one of four data collection waves between 2000-2010. Ten questions from the RAND-36 (SF-36) survey were used to construct physical functioning trajectories with latent class growth mixture models. Mortality was accounted for in competing risk models. A five-class solution provided the optimal number of trajectories: "intact," "high stable," "high and declining," "intermediate and declining," and "consistently low" functioning. Compared with low CVD risk, high CVD risk in midlife decreased the risk of being classified into the intact (fully adjusted β = -3.98; standard error = 2.0; P = .046) relative to the consistently low physical functioning trajectory. Compared with low CVD risk, those with signs of CVD were less likely to follow the intact, high stable, or high and declining relative to the consistently low trajectory (all P < .018). Among businessmen, a more favorable CVD profile in midlife was associated with better development of physical functioning in old age. J Am Geriatr Soc 67:2490-2496, 2019.

Declines in Sexual Activity and Function Predict Incident Health Problems in Older Adults: Prospective Findings from the English Longitudinal Study of Ageing

The objective of this study was to investigate cross-sectional and longitudinal associations between declines in sexual activity and function and health outcomes in a large population-based sample of older adults. Data were from 2577 men and 3195 women aged ≥ 50 years participating in the English Longitudinal Study of Ageing. Past-year changes in sexual desire, frequency of sexual activity, and ability to have an erection (men)/become sexually aroused (women) were assessed at baseline by self-completion questionnaire. Health outcomes (self-rated health, limiting long-standing illness, doctor-diagnosed diseases of the vascular system, and cancer) were self-reported at baseline (2012/2013) and 4-year follow-up (2016/2017). Data were analyzed using logistic regression, adjusted for sociodemographics, health behaviors, and depressive symptoms. Prospectively, men who reported a decline in sexual desire had higher odds of incident limiting long-standing illness (OR 1.41, 95% CI 1.04–1.91) and incident cancer (OR 1.63, 95% CI 1.06–2.50) than those who maintained their sexual desire. Men who reported a decline in the frequency of sexual activities had higher odds of deterioration in self-rated health (OR 1.47, 95% CI 1.04–2.08) and incident limiting long-standing illness (OR 1.69, 95% CI 1.20–2.37). In women, a decline in frequency of sexual activities was associated with deterioration of self-rated health (OR 1.64, 95% CI 1.07–2.51). Erectile dysfunction was longitudinally associated with poorer health outcomes including incident cancer (OR 1.73, 95% CI 1.11–2.70), coronary heart disease (OR 2.29, 95% CI 1.29–4.07), and fair/poor self-rated health (OR 1.66, 95% CI 1.19–2.32). Practitioners should be mindful that a decline in sexual activity, desire, or function in older age may be an important indicator of future adverse health outcomes.

Oral Health, Disability and Physical Function: Results From Studies of Older People in the United Kingdom and United States of America

ObjectivesStudies examining the associations between oral health and disability have limited oral health measures. We investigated the association of a range of objectively and subjectively assessed oral health markers with disability and physical function in older age. Design, Setting, and ParticipantsCross-sectional analyses were based on the British Regional Heart Study (BRHS) comprising men aged 71 to 92 years (n = 2147) from 24 British towns, and the Health, Aging, and Body Composition (HABC) Study comprising men and women aged 71 to 80 years (n = 3075) from the United States. Assessments included oral health (periodontal disease, tooth count, dry mouth, and self-rated oral health), disability, and physical function (grip strength, gait speed, and chair stand test). ResultsIn the BRHS, dry mouth, tooth loss, and cumulative oral health problems (≥3 problems) were associated with mobility limitations and problems with activities of daily living and instrumental activities of daily living; these remained significant after adjustment for confounding variables (for ≥3 dry mouth symptoms, odds ratio (OR) 2.68, 95% confidence interval (CI) 1.94–3.69; OR 1.76, 95% CI 1.15–2.69; OR 2.90, 95% CI 2.01, 4.18, respectively). Similar results were observed in the HABC Study. Dry mouth was associated with the slowest gait speed in the BRHS, and the weakest grip strength in the HABC Study (OR 1.75, 95% CI 1.22, 2.50; OR 2.43, 95% CI 1.47–4.01, respectively). Conclusions and ImplicationsMarkers of poor oral health, particularly dry mouth, poor self-rated oral health, and the presence of more than 1 oral health problem, were associated with disability and poor physical function in older populations. Prospective investigations of these associations and underlying pathways are needed.

Repeat variations in polyglutamine disease–associated genes and cognitive function in old age

Although the heritability of cognitive function in old age is substantial, genome-wide association studies have had limited success in elucidating its genetic basis, leaving a considerable amount of “missing heritability.” Aside from single nucleotide polymorphisms, genome-wide association studies are unable to assess other large sources of genetic variation, such as tandem repeat polymorphisms. Therefore, here, we studied the association of cytosine-adenine-guanine (CAG) repeat variations in polyglutamine disease–associated genes (PDAGs) with cognitive function in older adults. In a large cohort consisting of 5786 participants, we found that the CAG repeat number in 3 PDAGs (TBP, HTT, and AR) were significantly associated with the decline in cognitive function, which together accounted for 0.49% of the variation. Furthermore, in an magnetic resonance imaging substudy, we found that CAG repeat polymorphisms in 4 PDAGs (ATXN2, CACNA1A, ATXN7, and AR) were associated with different imaging characteristics, including brain stem, putamen, globus pallidus, thalamus, and amygdala volumes. Our findings indicate that tandem repeat polymorphisms are associated with cognitive function in older adults and highlight the importance of PDAGs in elucidating its missing heritability.

The Longitudinal Relationship of Perceived Stress Predicting Subsequent Decline in Executive Functioning in Old Age Is Attenuated in Individuals with Greater Cognitive Reserve

Background: Cognitively stimulating activities contribute to the accumulation of cognitive reserve that is proposed to be instrumental for maintaining cognitive functioning in aging. Adopting a novel, more general conceptual perspective including models of vulnerability, we argue that cognitive reserve may modify the longitudinal association between perceived stress and the rate of subsequent decline in executive functioning. Objective: The present study set out to investigate the longitudinal relationship between perceived stress and subsequent decline in executive functioning over 6 years as measured through performance changes in the Trail Making Test (TMT) and whether this longitudinal relationship differed by key markers of cognitive reserve (education, occupation, and leisure activities), taking into account age, sex, and chronic diseases as covariates. Methods: We used latent change score modeling based on longitudinal data from 897 older adults tested on TMT parts A and B in two waves 6 years apart. Mean age in the first wave was 74.33 years. Participants reported information on perceived stress, education, occupation, leisure activities, and chronic diseases. Results: The longitudinal relationship between greater perceived stress in the first wave of data collection and steeper subsequent decline in executive functioning over 6 years was significantly reduced in individuals who had pursued a higher frequency of leisure activities in the first wave. Conclusion: The longitudinal relationship between perceived stress and subsequent decline in executive functioning may be attenuated in individuals who have accumulated greater cognitive reserve through an engaged lifestyle. Implications for current cognitive reserve and gerontological research are discussed.

Gut Microbiota, Muscle Mass and Function in Aging: A Focus on Physical Frailty and Sarcopenia.

Human gut microbiota is able to influence the host physiology by regulating multiple processes, including nutrient absorption, inflammation, oxidative stress, immune function, and anabolic balance. Aging is associated with reduced microbiota biodiversity, increased inter-individual variability, and over-representation of pathobionts, and these phenomena may have great relevance for skeletal muscle mass and function. For this reason, the presence of a gut-muscle axis regulating the onset and progression of age-related physical frailty and sarcopenia has been recently hypothesized. In this narrative review, we summarize the studies supporting a possible association between gut microbiota-related parameters with measures of muscle mass, muscle function, and physical performance in animal models and humans. Reduced muscle mass has been associated with distinct microbiota composition and reduced fermentative capacity in mice, and the administration of probiotics or butyrate to mouse models of muscle wasting has been associated with improved muscle mass. However, no studies have targeted the human microbiome associated with sarcopenia. Limited evidence from human studies shows an association between microbiota composition, involving key taxa such as Faecalibacterium and Bifidobacterium, and grip strength. Similarly, few studies conducted on patients with parkinsonism showed a trend towards a different microbiota composition in those with reduced gait speed. No studies have assessed the association of fecal microbiota with other measures of physical performance. However, several studies, mainly with a cross-sectional design, suggest an association between microbiota composition and frailty, mostly assessed according to the deficit accumulation model. Namely, frailty was associated with reduced microbiota biodiversity, and lower representation of butyrate-producing bacteria. Therefore, we conclude that the causal link between microbiota and physical fitness is still uncertain due to the lack of targeted studies and the influence of a large number of covariates, including diet, exercise, multimorbidity, and polypharmacy, on both microbiota composition and physical function in older age. However, the relationship between gut microbiota and physical function remains a very promising area of research for the future.