Ecological Relevance Determines Task Priority in Older Adults' Multitasking

Objectives: Multitasking is a challenging aspect of human behavior, especially if the concurrently performed tasks are different in nature. Several studies demonstrated pronounced performance decrements (dual-task costs) in older adults for combinations of cognitive and motor tasks. However, patterns of costs among component tasks differed across studies and reasons for participants' resource allocation strategies remained elusive.
Method:We investigated young and older adults' multitasking of a working memory task and two sensorimotor tasks, one with low (finger force control) and one with high ecological relevance (postural control). The tasks were performed in single-, dual-, and triple-task contexts.
Results: Working memory accuracy was reduced in dual-task contexts with either sensorimotor task and deteriorated further under triple-task conditions. Postural and force performance deteriorated with age and task difficulty in dual-task contexts. However, in the triple-task context with its maximum resource demands, older adults prioritized postural control
over both force control and memory.
Discussion: Our results identify ecological relevance as the key factor in older adults’ multitasking.

Understanding coronary heart disease-related disability in older adults in the Republic of Ireland and Northern Ireland in 2010/2011

Background

Although life expectancy continues to increase in the Republic of Ireland (ROI) and Northern Ireland (NI), coronary heart disease (CHD) remains a leading cause of death and disability in older adults. Some, but not all, of the socioeconomic inequality in cardiovascular disability can be explained by a social gradient in conventional risk factors. The aims of the research were to assess CHD-related disability, and to establish the prevalence and population attributable fractions (PAFs) of risk factors for CHD-related disability across gender and socioeconomic groups in older adults in NI and ROI.

Successful balance training is associated with improved multisensory function in fall-prone older adults

Balance maintenance relies on a complex interplay between many different sensory modalities. Although optimal multisensory processing is thought to decline with ageing, inefficient integration is particularly associated with falls in older adults. We investigated whether improved balance control, following a novel balance training intervention, was associated with more efficient multisensory integration in older adults, particularly those who have fallen in the past. Specifically, 76 healthy and fall-prone older adults were allocated to either a balance training programme conducted over 5 weeks or to a passive control condition. Balance training involved a VR display in which the on-screen position of a target object was controlled by shifts in postural balance on a Wii balance board. Susceptibility to the sound-induced flash illusion, before and after the intervention (or control condition), was used as a measure of multisensory function. Whilst balance and postural control improved for all participants assigned to the Intervention group, improved functional balance was correlated with more efficient multisensory processing in the fall-prone older adults only. Our findings add to growing evidence suggesting important links between balance control and multisensory interactions in the ageing brain and have implications for the development of interventions designed to reduce the risk of falls.

Relationships between Oral Health and Nutritional Status of Older Adults

Objectives: The World Health Organisation has highlighted the paucity of research into the oral health needs of older adults. In particular, the relationships between oral health and nutritional status require further investigation and analysis. This study aimed to describe some of the relationships between the number of remaining occluding tooth contacts, oral health related quality of life and nutritional status of partially dentate older adults.

Methods: 45 partially dentate patients aged 65 years and older were recruited to the study after visiting a university dental hospital. An initial dental examination charted the remaining teeth including the number of occluding contacts. Oral health related quality of life was recorded using the 14 item Oral Health Impact Profile. Nutritional status was measured using the Mini Nutritional Assessment (MNA) in addition to biochemical analysis of a haematological sample. Correlation between data values was measured using a Pearson's correlation coefficient (r).

Results: The patient sample was made up of 44% males and 56% females with a mean age of 72.4 years (range 65-84 years). With increasing age the patients' oral health related quality of life scores improved. (r=-0.25) Within the sample the number of occluding tooth contacts ranged from 6 to 11. It was found that as the number of occluding contacts increased, better oral health related quality of life scores were recorded. (r=-0.30) Generally mini nutritional assessment scores improved with increasing numbers of tooth contacts. (r=0.14) In addition, as the number of occluding teeth contacts increased total lymphocyte count (r=0.35), vitamin B12 (r=0.22) and serum folate (r=0.06) all increased.

Conclusions: In older patients increased numbers of tooth contacts are associated with better oral health related quality of life. Increasing numbers of occluding contacts are also associated with better MNA scores and some haematological indicators of nutritional status.

Impact of smoking and smoking cessation on cardiovascular events and mortality among older adults: meta-analysis of individual participant data from prospective cohort studies of the CHANCES consortium

OBJECTIVE: To investigate the impact of smoking and smoking cessation on cardiovascular mortality, acute coronary events, and stroke events in people aged 60 and older, and to calculate and report risk advancement periods for cardiovascular mortality in addition to traditional epidemiological relative risk measures.

DESIGN: Individual participant meta-analysis using data from 25 cohorts participating in the CHANCES consortium. Data were harmonised, analysed separately employing Cox proportional hazard regression models, and combined by meta-analysis.

RESULTS: Overall, 503,905 participants aged 60 and older were included in this study, of whom 37,952 died from cardiovascular disease. Random effects meta-analysis of the association of smoking status with cardiovascular mortality yielded a summary hazard ratio of 2.07 (95% CI 1.82 to 2.36) for current smokers and 1.37 (1.25 to 1.49) for former smokers compared with never smokers. Corresponding summary estimates for risk advancement periods were 5.50 years (4.25 to 6.75) for current smokers and 2.16 years (1.38 to 2.39) for former smokers. The excess risk in smokers increased with cigarette consumption in a dose-response manner, and decreased continuously with time since smoking cessation in former smokers. Relative risk estimates for acute coronary events and for stroke events were somewhat lower than for cardiovascular mortality, but patterns were similar.

CONCLUSIONS: Our study corroborates and expands evidence from previous studies in showing that smoking is a strong independent risk factor of cardiovascular events and mortality even at older age, advancing cardiovascular mortality by more than five years, and demonstrating that smoking cessation in these age groups is still beneficial in reducing the excess risk.

Duration-dependent effects of the BDNF Val66Met polymorphism on anodal tDCS induced motor cortex plasticity in older adults: a group and individual perspective

The brain derived neurotrophic factor (BDNF) Val66Met polymorphism and stimulation duration are thought to play an important role in modulating motor cortex plasticity induced by non-invasive brain stimulation (NBS). In the present study we sought to determine whether these factors interact or exert independent effects in older adults. Fifty-four healthy older adults (mean age = 66.85 years) underwent two counterbalanced sessions of 1.5 mA anodal transcranial direct current stimulation (atDCS), applied over left M1 for either 10 or 20 min. Single pulse transcranial magnetic stimulation (TMS) was used to assess corticospinal excitability (CSE) before and every 5 min for 30 min following atDCS. On a group level, there was an interaction between stimulation duration and BDNF genotype, with Met carriers (n = 13) showing greater post-intervention potentiation of CSE compared to Val66Val homozygotes homozygotes (n = 37) following 20 min (p = 0.002) but not 10 min (p = 0.219) of stimulation. Moreover, Met carriers, but not Val/Val homozygotes, exhibited larger responses to TMS (p = 0.046) after 20 min atDCS, than following 10 min atDCS. On an individual level, two-step cluster analysis revealed a considerable degree of inter-individual variability, with under half of the total sample (42%) showing the expected potentiation of CSE in response to atDCS across both sessions. Intra-individual variability in response to different durations of atDCS was also apparent, with one-third of the total sample (34%) exhibiting LTP-like effects in one session but LTD-like effects in the other session. Both the inter-individual (p = 0.027) and intra-individual (p = 0.04) variability was associated with BDNF genotype. In older adults, the BDNF Val66Met polymorphism along with stimulation duration appears to play a role in modulating tDCS-induced motor cortex plasticity. The results may have implications for the design of NBS protocols for healthy and diseased aged populations.

Designing games for older adults: an affordance based approach

The main purpose of this study is to determine the game principles that need to be adopted in order to create an enjoyable and engaging game experience for older adults, whilst ensuring that the purpose of the game, encouraging upper limb mobility, is respected. The study reported in this paper involved a group of older adults who played and gave feedback on an early game prototype which feed into the design modification process. Each player's action capabilities were measured and taken into account in the design process. This helped ensure that opportunities for action that the game afforded were adapted to players' need.

Smoking and All-cause Mortality in Older Adults: Results From the CHANCES Consortium

INTRODUCTION: Smoking is known to be a major cause of death among middle-aged adults, but evidence on its impact and the benefits of smoking cessation among older adults has remained limited. Therefore, we aimed to estimate the influence of smoking and smoking cessation on all-cause mortality in people aged ≥60 years.

METHODS: Relative mortality and mortality rate advancement periods (RAPs) were estimated by Cox proportional hazards models for the population-based prospective cohort studies from Europe and the U.S. (CHANCES [Consortium on Health and Ageing: Network of Cohorts in Europe and the U.S.]), and subsequently pooled by individual participant meta-analysis. Statistical analyses were performed from June 2013 to March 2014.

RESULTS: A total of 489,056 participants aged ≥60 years at baseline from 22 population-based cohort studies were included. Overall, 99,298 deaths were recorded. Current smokers had 2-fold and former smokers had 1.3-fold increased mortality compared with never smokers. These increases in mortality translated to RAPs of 6.4 (95% CI=4.8, 7.9) and 2.4 (95% CI=1.5, 3.4) years, respectively. A clear positive dose-response relationship was observed between number of currently smoked cigarettes and mortality. For former smokers, excess mortality and RAPs decreased with time since cessation, with RAPs of 3.9 (95% CI=3.0, 4.7), 2.7 (95% CI=1.8, 3.6), and 0.7 (95% CI=0.2, 1.1) for those who had quit <10, 10 to 19, and ≥20 years ago, respectively.

CONCLUSIONS: Smoking remains as a strong risk factor for premature mortality in older individuals and cessation remains beneficial even at advanced ages. Efforts to support smoking abstinence at all ages should be a public health priority.

Proprioceptive acuity predicts muscle co-contraction of the tibalis anterior and gastrocnemius medialis in older adults’ dynamic postural control

Older adults use a different muscle strategy to cope with postural instability, in which they ‘co-contract’ the muscles around the ankle joint. It has been suggested that this is a compensatory response to age-related proprioceptive decline however this view has never been assessed directly. The current study investigated the association between proprioceptive acuity and muscle co-contraction in older adults. We compared muscle activity, by recording surface EMG from the bilateral tibalis anterior and gastrocnemius medialis muscles, in young (aged 18-34) and older adults (aged 65-82) during postural assessment on a fixed and sway-referenced surface at age-equivalent levels of sway. We performed correlations between muscle activity and proprioceptive acuity, which was assessed using an active contralateral matching task. Despite successfully inducing similar levels of sway in the two age groups, older adults still showed higher muscle co-contraction. A stepwise regression analysis showed that proprioceptive acuity measured using variable error was the best predictor of muscle co-contraction in older adults. However, despite suggestions from previous research, proprioceptive error and muscle co-contraction were negatively correlated in older adults, suggesting that better proprioceptive acuity predicts more co-contraction. Overall, these results suggest that although muscle co-contraction may be an age-specific strategy used by older adults, it is not to compensate for age-related proprioceptive deficits.

Root caries development in older adults- a prospective cohort study

Objectives: To identify factors associated with root caries development during a two year period in a population of independently living older adults. Methods: A prospective cohort study was carried out with 334 independently living volunteers aged 65 and older. At baseline (t0), each participant completed a questionnaire which recorded age, gender, medical history, fluoride exposure, oral and denture hygiene practices, smoking and alcohol consumption, diet information, and socio economic information. Clinical examinations were performed and stimulated saliva samples were collected. Patients were reviewed 12(t1) and 24(t2) months later to determine the root caries increment. Results: 307 adults were assessed at t1 and 280 were assessed at t2 with 83.8% of participants examined at 24 months. Incidence of root caries in this cohort was 17.4% at t1 and 21.6% at t2. The mean root caries increment was 0.43 (SD 1.45) surfaces at t1 and 0.70 (SD 1.86) surfaces at t2. Age >70 years, completing education at primary level, poor oral hygiene, xerostomia, coronal decay at baseline, higher root caries index at baseline and number of exposed root surfaces showed a statistically significant association (P < 0.05) with root caries development. Conclusion: Root caries is a substantive dental health problem for our older population. Root caries prevention strategies should be targeted at older adults who have poor plaque control and high levels of caries experience. In particular patients with xerostomia should be targeted with preventive measures.