Exploring public perceptions and awareness of Parkinson's disease: A scoping review.

BACKGROUND: Parkinson's disease (PD) is a common neurological disease affecting around 1% of people above sixty years old. It is characterised by both motor and non-motor symptoms including tremor, slow movement, unsteady gait, constipation and urinary incontinence. As the disease progresses, individuals living with the disease are likely to lose their independence and autonomy, subsequently affecting their quality of life. People with PD should be supported to live well within their communities but there has been limited research regarding what the public know about PD. This review aims to develop an understanding of how the public view people living with PD, which has the potential to aid the development of an educational resource for the future to improve public awareness and understanding of PD. The purpose of this scoping review is to review and synthesise the literature on the public perception and attitudes towards people living with PD and identify and describe key findings. AIM: This scoping review aims to explore public perceptions and awareness of Parkinson's Disease among diverse populations, encompassing beliefs, knowledge, attitudes, and the broader societal context influencing these perceptions. METHODS: A scoping review of the literature was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analysis extension for ScR (PRISMA-ScR). Four electronic databases were searched systematically (CINAHL Plus, Medline, PsycINFO and International Bibliography of the Social Sciences). The Joanna Briggs Institute Critical Appraisal Tools (JBI) were used to assess the quality of primary studies, however, all relevant studies were considered regardless of their methodological quality. The 'Population-Concept-Context' framework was used in the screening process to identify eligible papers. RESULTS: A total of 23 studies were included in the review representing global research in quantitative (n = 12) and mixed methods approaches (n = 11). All 23 studies adopted some aspect of cross-sectional design. Three themes emerged from the studies, the first being public knowledge of symptoms, causes and treatment of PD and this highlighted a lack of understanding about the disease. Secondly, the review identified public attitudes towards PD, highlighting the social consequences of the disease, including the association between PD and depression, isolation and loss of independence. Finally, the third theme highlighted that there was a paucity of educational resources available to help increase public understanding of PD. CONCLUSION: Findings from this scoping review have indicated that public awareness of PD is a growing area of interest. To our knowledge, this is the first scoping review on this topic and review findings have indicated that public knowledge and attitudes towards PD vary internationally. The implications of this are that people with PD are more likely to be a marginalised group within their communities. Future research should focus on understanding the perception of the public from the perspective of people with PD, the development of interventions and awareness campaigns to promote public knowledge and attitude and further high-quality research to gauge public perceptions of PD.

Circulating microvesicles across a population with various degree of cardiovascular burden are associated with systolic blood pressure.

Circulating microvesicles (MVs) have been studied in heterogeneous, divergent, and rather small patient populations with cardiovascular risk . Therefore, we measured endothelial (EMVs), platelet (PMVs) and erythrocyte (RMVs) MVs in patients with divergent cardiovascular risk. We then compared them to coronary artery disease (CAD) and healthy subjects and identified independent MVs' predictors. We enrolled consecutive patients from our Cardiology, Hypertension, Diabetic, Rheumatic, and Nephrology Outpatient Units with MVs measurements. Central blood pressure (BP) was measured by either applanation tonometry or Mobil-O-graph device, while MVs by a standardized flow cytometry protocol. We studied 369 participants with increased cardiovascular risk: 63 with high cardiovascular risk (47 diabetes mellitus type II/DM and 16 end-stage renal disease/ESRD), 92 with chronic inflammatory disorders and 73 with untreated essential hypertension/UEH. We further included 53 subjects with CAD and 87 otherwise healthy individuals. All MVs were lower in patients with increased cardiovascular risk compared to CAD, showing predictive value with high sensitivity and specificity. Furthermore, PMVs and EMVs were increased in patients with cardiovascular risk compared to healthy individuals. DM and ESRD patients had increased EMVs versus UEH and chronic inflammatory disorders. In the whole study population, RMVs were associated only with history of essential hypertension. In multivariate analysis, systolic BP predicted PMVs. Aage, systolic BP, and DM predicted EMVs. In a large population of patients with divergent cardiovascular risk, MVs are independently associated with systolic blood pressure.

Short vs long-course antibiotic therapy in adults with acute cholangitis: A systematic review, meta-analysis, and evidence quality assessment.

BACKGROUND: Acute cholangitis (AC) constitutes an infection with increased mortality rates in the past. Due to new diagnostic tools and therapeutic methods, the mortality of AC has been significantly reduced nowadays. The initial antibiotic treatment of AC has been oriented to the most common pathogens connected to this infection. However, the optimal duration of the antibiotic treatment of AC is still debatable. AIM: To investigate if shorter-course antibiotic treatments could be similarly effective to long-course treatments in adults with AC. METHODS: This study constitutes a systematic review and meta-analysis of the existing literature concerning the duration of antibiotic therapy of AC and an assessment of the quality of the evidence. The study was conducted in accordance with the recommendations of the Preferred Reporting Items for Systematic Review and Meta-Analyses. Fifteen studies were included in the systematic review, and eight were eligible for meta-analysis. Due to heterogeneous duration cutoffs, three study-analysis groups were formed, with a cutoff of 2-3, 6-7, and 14 d. RESULTS: A total of 2763 patients were included in the systematic review, and 1313 were accounted for the meta-analysis. The mean age was 73.66 ± 14.67 years, and the male and female ratio was 1:08. No significant differences were observed in the mortality rates of antibiotic treatment of 2-3 d, compared to longer treatments (odds ratio = 0.78, 95% confidence interval: 0.23-2.67, I2 = 9%) and the recurrence rates and hospitalization length were also not different in all study groups. CONCLUSION: Short- and long-course antibiotic treatments may be similarly effective concerning the mortality and recurrence rates of AC. Safe conclusions cannot be extracted concerning the hospitalization duration.

Dual-task walking on real-world surfaces: Adaptive changes in walking speed, step width and step height in young and older adults.

OBJECTIVES: Age-related changes in dual-task walking are well established, but research in this topic is based on evidence from laboratory rather than real-world studies. We investigated how dual-task walking on real-world surfaces affects young and older adults' gait characteristics and cognitive resource allocation. METHOD: Sixteen young (aged 19-35, 12 female) and fifteen older adults (aged 70-85, 7 female) with no major neurological or musculoskeletal disorders walked at a self-selected speed on forty-metre outdoor paths that had asphalt or grass surface. They walked with or without a cognitive task (counting backwards). Cognitive task difficulty was individually adjusted at 80 % accuracy. Participants performed the three tasks in Single Task (ST Asphalt, ST Grass, ST Cognitive) and Dual Task context (DT Asphalt-Cognitive, DT Grass-Cognitive). RESULTS: The two groups showed similar dual task effects in cognition and walking speed, both of which were slower when dual-task walking. Older adults' steps were wider overall but only young adults widened their step width when dual-task walking on grass compared to asphalt. Similarly, young adults' step height increased from single to dual-task walking when on grass, where older adults' did not. DISCUSSION: The lack of adaptation of step width and height when dual-task walking may leave older adults vulnerable to tripping or falling in common real-world conditions, such as while walking on grass, gravel, or uneven city sidewalks. Considering this, the built environment should be made more accessible to facilitate older adults' safe walking.

Casivirimab/Imdevimab Effect on COVID-19 Outcome and Reinfection in a Real-World SARS-COV-2 Variant Transition Period Setting.

Monoclonal antibodies targeted against SARS-COV-2 have been recruited in the challenging treatment of COVID-19 with few clinically significant side effects. Casivirimab/imdevimab, a combination of monoclonal antibodies targeted against SARS-COV-2 spike protein, was shown to effectively prevent recently infected high-risk COVID-19 patients from developing severe disease. Its efficacy waned with the emergence of the resistant omicron variant in late 2021. We recorded the real-world effect of casivirimab/imdevimab on 116 high-risk COVID-19 patients. Cumulative need for hospitalization, mortality, new-onset disease, and reinfections was monitored. Casivirimab/imdevimab effect was independent from previous immunization. The cohort was further divided into two subgroups: patients infected during a delta variant prevalent period were more likely to become admitted but as likely to die than patients infected with the omicron variant, in support of its protective effect from clinical studies. Cumulative reinfection incidence in treated patients, interestingly, was lower than in the general population.

Evaluating the effects of dance on motor outcomes, non-motor outcomes, and quality of life in people living with Parkinson's: a feasibility study.

BACKGROUND: Community-based dance programs for people living with Parkinson's have grown in popularity over the past two decades. Studies investigating these programs have demonstrated multidimensional benefits in motor, non-motor, and quality of life related outcomes, yet there is a need to focus on the feasibility of larger trials. The primary objective of this study was to assess the feasibility and acceptability of conducting a trial investigating dance and Parkinson's in Northern Ireland. The secondary objectives were to conduct preliminary analyses of the classes' effects and to assess the appropriateness of outcome measures for a randomized controlled trial. METHODS: Participants were recruited through the community, Parkinson's UK, and university contacts to participate in a 12-week dance intervention inspired by the Dance for PD® model. Pre- and post-intervention, participants completed the following outcomes: MDS-UPDRS III, TUG, DT-TUG, Sensory Organization Test, MoCA, Trail Making Tests A&B, Digit Symbol Substitution Test, Digit Span, PDQ-39, FOG-Q, PHQ-9, FES-I, and an exit questionnaire (post-test only). Data were analyzed using paired samples t tests or Wilcoxon signed ranked test. RESULTS: Ten people living with Parkinson's participated. Running a larger trial was deemed infeasible in this setting due to recruitment issues; conversely, the dance intervention was accepted by participants with all but one completing the study. Functional mobility (TUG), symptoms of depression (PHQ-9), and bodily discomfort showed improvement. All other outcomes did not. The exit questionnaire revealed that the social aspect of classes was important, and improvements in mood or mental state were cited most frequently as perceived benefits. Outcome measures were feasible, with some changes suggested for future trials. CONCLUSIONS: This study highlighted the infeasibility of running a larger trial using this design in this setting despite demonstrating the acceptability of implementing a dance program in Northern Ireland for people living with Parkinson's. The results support existing evidence demonstrating that dance may improve functional mobility and symptoms of depression in people living with Parkinson's, though the study design and small sample size prevent the generalizability of results. The findings also support the idea that dancing has the potential to support several aspects of physical, emotional, mental, and social health.

Single Leg Balance Training: A Systematic Review.

Single leg balance training promotes significant increments in balance control, but previous reviews on balance control have not analyzed this form of balance training. Accordingly, we aimed to review the single leg balance training literature to better understand the effects of applying this training to healthy individuals. We searched five databases-PubMed, EMBASE, Scopus, Lilacs, and Scielo-with the following inclusion criteria: (a) peer-reviewed articles published in English; (b) analysis of adult participants who had no musculoskeletal injuries or diseases that might impair balance control; and (c) use of methods containing at least a pre-test, exclusive single leg balance training, and a post-test assessment. We included 13 articles meeting these criteria and found that single leg balance training protocols were effective in inducing balance control gains in either single- or multiple-session training and with or without progression of difficulty. Balance control gains were achieved with different amounts of training, ranging from a single short session of 10 minutes to multiple sessions totaling as much as 390 min of unipedal balance time. Generalization of balance gains to untrained tasks and cross-education between legs from single leg balance training were consistent across studies. We concluded that single leg balance training can be used in various contexts to improve balance performance in healthy individuals. These results extend knowledge of expected outcomes from this form of training and aid single leg balance exercise prescription regarding volume, frequency, and potential progressions.

Dual task walking in healthy aging: Effects of narrow and wide walking paths.

Dual-task walking may lead to gait instability and a higher fall risk in older adults, particularly when walking in a busy city street. Challenging street features such as narrow sidewalks not only discourage walking, but are also likely to be taxing for older adults' cognitive resources and gait characteristics. The aim of this study was to assess the way older adults' gait characteristics are affected by walking on a narrow path while performing a challenging cognitive task in lab conditions imitating common urban environments. Nineteen young and eighteen older adults walked on a narrow (40cm) and a wide (80cm) path and performed a cognitive (n-back) task individually adjusted to 80% accuracy. The two tasks were performed separately (Single-Task) and concurrently (Dual-Task). Both groups walked faster, and their step width was narrower on the narrow path. During dual-task walking on the narrow path, older adults showed significant dual-task costs in the cognitive task, gait speed, step width, and stride length. Dual-task walking was associated with decreased gait speed and stride length in both age groups, suggesting that dual-task walking may adversely affect gait, particularly when walking on narrow paths. These conditions may lead to gait instability and an increased fall risk for older adults, particularly when walking along the narrow sidewalks commonly found within the built environment. However, more research is needed in an urban setting to determine the extent of the fall risk narrow sidewalks present for older adults.

Adherence to Mediterranean Diet and Cognitive Abilities in the Greek Cohort of Epirus Health Study.

The Mediterranean diet is commonly proposed as a major modifiable protective factor that may delay cognitive impairment in the elderly. The aim of the study was to investigate the cross-sectional association of adherence to the Mediterranean diet with cognitive abilities in a younger Greek population. A total of 1201 healthy adults aged 21-77 years (mean: 47.8) from the Epirus Health Study cohort were included in the analysis. Adherence to the Mediterranean diet was measured using the 14-point Mediterranean Diet Adherence Screener (MEDAS) and cognition was measured using the Trail Making Test, the Verbal Fluency test and the Logical Memory test. Statistical analysis was performed using multiple linear regression models adjusted for age, sex, education, body mass index, smoking status, alcohol consumption and physical activity. Overall, no association was found between the MEDAS score and cognitive tests, which could be explained by the young mean age and high level of education of the participants. Future studies should target young and middle-aged individuals to gain further understanding of the association between Mediterranean diet and cognition in this age group.

Prevalence and Determinants of Sex-Specific Dietary Supplement Use in a Greek Cohort.

We describe the profile of dietary supplement use and its correlates in the Epirus Health Study cohort, which consists of 1237 adults (60.5% women) residing in urban north-west Greece. The association between dietary supplement use and demographic characteristics, lifestyle behaviors, personal medical history and clinical measurements was assessed using logistic regression models, separately for women and men. The overall prevalence of dietary supplement use was 31.4%, and it was higher in women (37.3%) compared to men (22.4%; p-value = 4.2-08). Based on multivariable logistic regression models, dietary supplement use in women was associated with age (positively until middle-age and slightly negatively afterwards), the presence of a chronic health condition (OR = 1.71; 95% CI, 1.18-2.46), lost/removed teeth (OR = 0.52; 95% CI, 0.35-0.78) and diastolic blood pressure (OR per 5 mmHg increase =0.84; 95% CI, 0.73-0.96); body mass index and worse general health status were borderline inversely associated. In men, dietary supplement use was positively associated with being employed (OR = 2.53; 95% CI, 1.21-5.29). A considerable proportion of our sample used dietary supplements, and the associated factors differed between women and men.

Awareness, knowledge and trust in the Greek authorities towards COVID-19 pandemic: results from the Epirus Health Study cohort.

BACKGROUND: To assess the level of knowledge and trust in the policy decisions taken regarding the coronavirus disease (COVID-19) pandemic among Epirus Health Study (EHS) participants. METHODS: The EHS is an ongoing and deeply-phenotyped prospective cohort study that has recruited 667 participants in northwest Greece until August 31st, 2020. Level of knowledge on coronavirus (SARS-CoV-2) transmission and COVID-19 severity was labeled as poor, moderate or good. Variables assessing knowledge and beliefs towards the pandemic were summarized overall and by sex, age group (25-39, 40-49, 50-59, ≥60 years) and period of report (before the lifting of lockdown measures in Greece: March 30th to May 3rd, and two post-lockdown time periods: May 4th to June 31st, July 1st to August 31st). A hypothesis generating exposure-wide association analysis was conducted to evaluate the associations between 153 agnostically-selected explanatory variables and participants' knowledge. Correction for multiple comparisons was applied using a false discovery rate (FDR) threshold of 5%. RESULTS: A total of 563 participants (49 years mean age; 60% women) had available information on the standard EHS questionnaire, the clinical and biochemical measurements, and the COVID-19-related questionnaire. Percentages of poor, moderate and good knowledge status regarding COVID-19 were 4.5, 10.0 and 85.6%, respectively. The majority of participants showed absolute or moderate trust in the Greek health authorities for the management of the epidemic (90.1%), as well as in the Greek Government (84.7%) and the official national sources of information (87.4%). Trust in the authorities was weaker in younger participants and those who joined the study after the lifting of lockdown measures (p-value≤0.001). None of the factors examined was associated with participants' level of knowledge after correction for multiple testing. CONCLUSIONS: High level of knowledge about the COVID-19 pandemic and trust in the Greek authorities was observed, possibly due to the plethora of good quality publicly available information and the timely management of the pandemic at its early stages in Greece. Information campaigns for the COVID-19 pandemic should be encouraged even after the lifting of lockdown measures to increase public awareness.

The efficacy of dance for improving motor impairments, non-motor symptoms, and quality of life in Parkinson's disease: A systematic review and meta-analysis.

Dance may help individuals living with Parkinson's disease (PD) improve motor and non-motor symptoms that impact quality of life (QOL). The primary aim of this systematic review of randomized controlled trials (RCTs) was to evaluate the efficacy of dance in improving motor and non-motor symptoms of PD and QOL. The secondary aims of this review were to evaluate the methodological quality of included studies by assessing risk of bias across nine categories and to inform the direction of future research. Peer-reviewed RCTs that included people living with PD at all disease stages and ages and measured the effects of a dance intervention longer than one day were included. Sixteen RCTs involving 636 participants with mild to moderate PD were eligible for inclusion in the qualitative synthesis and nine in the meta-analysis. Overall, the reviewed evidence demonstrated that dance can improve motor impairments, specifically balance and motor symptom severity in individuals with mild to moderate PD, and that more research is needed to determine its effects on non-motor symptoms and QOL. RCTs that use a mixed-methods approach and include larger sample sizes will be beneficial in fully characterizing effects and in determining which program elements are most important in bringing about positive, clinically meaningful changes in people with PD.

Satisfaction and Perceived Barriers of General Practice Residents in Relation to Their Educational Needs Coverage During Residency in Greece.

Objectives: This study aimed to assess satisfaction and report on perceptions of General Practice (GP) residents during residency in Greece, through an online questionnaire at a national level. Material and methods:A mixed type method study was shaped. Both quantitative analysis and a quasiqualitative approach were used, while information from an open-ended question was processed. The study included answers of GP residents recruited with a national sample pool technique. Results:There were 177 responders from 430 registered residents. Using a grading system from 1 to 10, the median value showing how much satisfied the participants were during their training was 4.48 (95% CI 4.16-4.79), while GP logbook was regarded as useful (median value 6.29, 95% CI 5.84-6.73). The training program was reported as insufficient to prepare residents for their future work as primary health care physicians, with a median rating of 4.09 (95% CI 3.78-4.41). The overall educational gain was regarded as poor compared to residents' expectations, with a median rating of 4.71 (95% CI 4.38-5.07). From free text responses of 83 participants, an organized educational program based on logbook skill acquirement with interaction between coordinator and resident emerged as a priority. Conclusion: Understanding general practitioners' perceptions, satisfaction level and expectations may help to design reform initiatives and cover their educational needs during residency in a holistic manner. Experience from local settings may be useful to offer more comprehensive messages. In a rapidly changing health environment, quickly collecting and analyzing emerging data appears to be a practical way for correcting decisions and avoiding previous errors.

Slowed sensory reweighting and postural illusions in older adults: the moving platform illusion.

We investigated whether postural aftereffects witnessed during transitions from a moving to a stable support are accompanied by a delayed perception of platform stabilization in older adults, in two experiments. In experiment 1, postural sway and muscle cocontraction were assessed in 11 healthy young, 11 healthy older, and 11 fall-prone older adults during blindfolded stance on a fixed platform, followed by a sway-referenced platform and then by a fixed platform again. The sway-referenced platform was more compliant for young adults, to induce similar levels of postural sway in both age groups. Participants were asked to press a button whenever they perceived that the platform had stopped moving. Both older groups showed significantly larger and longer postural sway aftereffects during platform stabilization compared with young adults, which were pronounced in fall-prone older adults. In both older groups elevated muscle cocontraction aftereffect was also witnessed. Importantly, these aftereffects were accompanied by an illusory perception of prolonged platform movement. After this, experiment 2 examined whether this illusory perception was a robust age effect or an experimental confound due to greater surface compliance in young adults, which could create a larger perceptual discrepancy between moving and stable conditions. Despite exposure to the same surface compliance levels during sway-reference, the perceptual illusion was maintained in experiment 2 in a new group of 14 healthy older adults compared with 11 young adults. In both studies, older adults took five times longer than young adults to perceive platform stabilization. This supports that sensory reweighting is inefficient in older adults. NEW & NOTEWORTHY This is the first paper to show that postural sway aftereffects witnessed in older adults after platform stabilization may be due to a perceptual illusion of platform movement. Surprisingly, in both experiments presented it took older adults five times longer than young adults to perceive platform stabilization. This supports a hypothesis of less efficient sensory reintegration in this age group, which may delay the formation of an accurate postural percept.

Putting proprioception for balance to the test: Contrasting and combining sway referencing and tendon vibration.

BACKGROUND: Postural control relies on sensory information from visual, vestibular and proprioceptive channels, with proprioception being the key sensory modality in this task. Two well-established ways of manipulating proprioceptive information in postural control are tendon vibration and sway referencing. The aim of the present study was to assess postural adaptation when inaccurate proprioceptive information is introduced using tendon vibration and sway referencing in isolation and combination. METHODS: Seventeen young adults were asked to stand, without vision, for 2 min on a fixed surface (baseline) immediately followed by 3 min of bilateral Achilles tendon vibration, sway reference, or combined presentation of the two manipulations (adaptation) and finally 3 min of standing on a fixed surface (aftereffect). RESULTS: During adaptation, vibration showed the lowest sway variability, followed by sway reference and the combined condition. Spectral analyses focusing on the dominant frequencies in this task (0-0.4 Hz) showed that in the first half of adaptation sway amplitude was greater when the two manipulations were combined compared with each manipulation alone. However, in the second half differences between sway reference and the combined condition disappeared but differences between vibration and the other two conditions increased. CONCLUSION: We interpret these findings primarily as due to a prolonged attenuation in effects of vibration over the course of the adaptation phase and we offer two explanations for this phenomenon. One is a decline in neurotransmitter release from the group Ia terminals and the other is sensory reweighting which down-weights proprioception and up-weights the accurate, vestibular information.

Educational strategies to train health care professionals across the education continuum on the process of frailty prevention and frailty management: a systematic review.

BACKGROUND: In addition to the normal process of ageing, frailty, defined as a geriatric syndrome, is becoming more prevalent. Around 10% of people over 65 years and 25-50% of those aged over 85 years are frail. Frail elderly are more vulnerable to external stressors and have an increased risk of adverse health outcomes. To tackle these challenges, European Union (EU) member states need to develop a health work force capable of the right skills mix. A goal-centred education and training of professionals is crucial for effective and efficient health care delivery for Europe's greying population. AIMS: The aim of this study was to systematically collect, review and critically appraise studies carried out to investigate the efficacy and effectiveness of comprehensive educational programmes for health professionals related to frailty prevention and/or frailty management. METHODS: A systematic review was carried out searching the databases PubMed, CINAHL, Cochrane CENTRAL, Medline, Up to date and Embase. Additionally, a manual search of the reference lists and searches via Google Scholar and greylit.org was done. RESULTS: No relevant publications addressing the evidence and sustainability of educational/training programmes for frailty prevention and/or frailty management were identified. DISCUSSION: The result of an empty review is surprising because several educational programmes in different countries are currently run. CONCLUSIONS: A significant knowledge gap exists in the scientific literature regarding education and training of health care workers regarding prevention and management of frailty. Further research is needed to identify effective educational strategies for health professionals to prevent and manage frailty.

Cognitively and socially induced stress affects postural control.

Postural control is an adaptive process that can be affected by many aspects of human behavior, including emotional contexts. The main emotional contexts that affect postural control are postural threat and passive viewing of aversive or threatening images, both of which produce a reduction in postural sway. The aim of the present study was to assess whether similar stress-related changes in postural sway can be observed using stress induced by social evaluative threat (SET) while performing arithmetic tasks. Twelve young adults performed an arithmetic and a postural control task separately, concurrently, and concurrently with added time pressure in the arithmetic task. In the final condition, participants were given negative feedback about their performance in the arithmetic task and performed it again while being observed (SET condition). Results showed that stress increased linearly with task demand. Postural sway and reaction times were not affected by the first two conditions; however, when time pressure was introduced, reaction times became faster and sway amplitude increased. Finally, introduction of SET caused the predicted reduction in postural sway and an increase in reaction times relative to the time pressure condition. Our results suggest that stress induced using a combination of arithmetic tasks and social evaluative threat leads to systematic changes in postural control. The paradigm developed in the present study would be very useful in assessing interactions between cognition, stress, and postural control in the context of postural instability and falls in older adults.

Effects of the availability of accurate proprioceptive information on older adults' postural sway and muscle co-contraction.

During conditions of increased postural instability, older adults exhibit greater lower limb muscle co-contraction. This response has been interpreted as a compensatory postural strategy, which may be used to increase proprioceptive information from muscle spindles or to stiffen the lower limb as a general response to minimise postural sway. The current study aimed to test these two hypotheses by investigating use of muscle co-contraction during sensory transitions that manipulated proprioceptive input. Surface EMG was recorded from the bilateral tibialis anterior and gastrocnemius medialis muscles, in young (aged 18-30) and older adults (aged 68-80) during blind-folded postural assessment. This commenced on a fixed platform (baseline: 2 min), followed by 3 min on a sway-referenced platform (adaptation) and a final 3 min on a fixed platform again (reintegration). Sensory reweighting was slower in older adults, as shown by a significantly larger and longer postural sway after-effect once a stable platform was restored. Muscle co-contraction showed similar after-effects, whereby older adults showed a larger increase in co-contraction once the stable platform had been restored, compared to young adults. This co-contraction after-effect did not return to baseline until after 1 min. Our evidence for high muscle co-contraction during the reintroduction of veridical proprioceptive input suggests that increased co-contraction in older adults is not dependent on contemporaneous proprioceptive input. Rather, it is more likely that co-contraction is a general postural strategy used to minimise postural sway, which is increased during this sensory transition. Future research should examine whether muscle co-contraction is typically a reactive or anticipatory response.

The Association between Hearing Loss, Postural Control, and Mobility in Older Adults: A Systematic Review.

BACKGROUND: Degraded hearing in older adults has been associated with reduced postural control and higher risk of falls. Both hearing loss (HL) and falls have dramatic effects on older persons' quality of life (QoL). A large body of research explored the comorbidity between the two domains. PURPOSE: The aim of the current review is to describe the comorbidity between HL and objective measures of postural control, to offer potential mechanisms underlying this relationship, and to discuss the clinical implications of this comorbidity. DATA COLLECTION AND ANALYSIS: PubMed and Google Scholar were systematically searched for articles published in English up until October 15, 2015, using combinations of the following strings and search words: for hearing: Hearing loss, "Hearing loss," hearing, presbycusis; for postural control: postural control, gait, postural balance, fall, walking; and for age: elderly, older adults. RESULTS: Of 211 screened articles, 7 were included in the systematic review. A significant, positive association between HL and several objective measures of postural control was found in all seven studies, even after controlling for major covariates. Severity of hearing impairment was connected to higher prevalence of difficulties in walking and falls. Physiological, cognitive, and behavioral processes that may influence auditory system and postural control were suggested as potential explanations for the association between HL and postural control. CONCLUSIONS: There is evidence for the independent relationship between HL and objective measures of postural control in the elderly. However, a more comprehensive understanding of the mechanisms underlying this relationship is yet to be elucidated. Concurrent diagnosis, treatment, and rehabilitation of these two modalities may reduce falls and increase QoL in older adults.