Predictors for the development of motoric cognitive risk syndrome in older adults.

BACKGROUND: Motoric cognitive risk (MCR) syndrome refers to a condition where both slow gait and memory complaints coexist, which heightens their vulnerability to developing dementia. Considering that the risk factors of MCR are elucidated from cross-sectional studies and also likely vary based on socioeconomic status, we conducted a community-based longitudinal study to determine the predictors of MCR among older adults in Malaysia. METHODS: Out of 1,249 older participants (aged 60 years and above) without MCR at baseline (Wave II of LRGS-TUA cohort study), 719 were successfully followed up after 3.5 years to identify predictors of subsequent MCR development. A comprehensive interview-based questionnaire was administered for sociodemographic information, cognitive function, psychosocial, functional status, and dietary intake. Anthropometric measurements, body composition, and physical performance were assessed. Univariate analyses were performed for each variable, followed by a hierarchical logistic regression analysis to identify the predictors of MCR that accounted for confounding effects between the studied factors. RESULTS: The incidence rate of MCR was 4.0 per 100 person-years. Smoking (Adjusted Odd Ratio (Adj OR) = 1.782; 95% Confidence Interval (CI):1.050-3.024), hypertension (Adj OR = 1.725; 95% CI:1.094-2.721), decreased verbal memory as assessed by the lower Rey Auditory Verbal Learning Test (RAVLT) (Adj OR = 1.891; 95% CI:1.103-3.243), and decreased functional status measured using instrumental activity of daily living (IADL) (Adj OR = 4.710; 95% CI:1.319-16.823), were predictors for MCR incidence. CONCLUSIONS: Our study results provide an initial reference for future studies to formulate effective preventive management and intervention strategies to reduce the growing burden of adverse health outcomes, particularly among Asian older adults.

Neural Correlates of Self-Reported Knee Function in Individuals After Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Anterior cruciate ligament (ACL) rupture is a common knee injury among athletes and physically active adults. Despite surgical reconstruction and extensive rehabilitation, reinjuries are common and disability levels are high, even years after therapy and return to activity. Prolonged knee dysfunction may result in part from unresolved neuromuscular deficits of the surrounding joint musculature in response to injury. Indeed, "upstream" neurological adaptations occurring after injury may explain these persistent functional deficits. Despite evidence for injury consequences extending beyond the joint to the nervous system, the link between neurophysiological impairments and patient-reported measures of knee function remains unclear. HYPOTHESIS: Patterns of brain activation for knee control are related to measures of patient-reported knee function in individuals after ACL reconstruction (ACL-R). STUDY DESIGN: Cross-sectional study. LEVEL OF EVIDENCE: Level 3. METHODS: In this multicenter, cross-sectional study, participants with unilateral ACL-R (n = 25; 10 men, 15 women) underwent task-based functional magnetic resonance imaging testing. Participants performed repeated cycles of open-chain knee flexion/extension. Neural activation patterns during the movement task were quantified using blood oxygen level-dependent (BOLD) signals. Regions of interest were generated using the Juelich Histological Brain Atlas. Pearson product-moment correlations were used to determine the relationship between mean BOLD signal within each brain region and self-reported knee function level, as measured by the International Knee Documentation Committee index. Partial correlations were also calculated after controlling for time from surgery and sex. RESULTS: Patient-reported knee function was positively and moderately correlated with the ipsilateral secondary somatosensory cortex (r = 0.57, P = 0.005) and the ipsilateral supplementary motor area (r = 0.51, P = 0.01). CONCLUSION: Increased ipsilateral secondary sensorimotor cortical activity is related to higher perceived knee function. CLINICAL RELEVANCE: Central nervous system mechanisms for knee control are related to subjective levels of knee function after ACL-R. Increased neural activity may reflect central neuroplastic strategies to preserve knee functionality after traumatic injury.

Self-Reported Dementia-Related Diagnosis Underestimates the Prevalence of Older Americans Living with Possible Dementia.

BACKGROUND: Dementia screening is an important step for appropriate dementia-related referrals to diagnosis and treat possible dementia. OBJECTIVE: We sought to estimate the prevalence of no reported dementia-related diagnosis in a nationally representative sample of older Americans with a cognitive impairment consistent with dementia (CICD). METHODS: The weighted analytical sample included 6,036,224 Americans aged at least 65 years old that were identified as having a CICD without history of stroke, cancers, neurological conditions, or brain damage who participated in at least one-wave of the 2010-2016 Health and Retirement Study. The adapted Telephone Interview of Cognitive Status assessed cognitive functioning. Those with scores≤6 were considered as having a CICD. Healthcare provider dementia-related diagnosis was self-reported. Age, sex, educational achievement, and race and ethnicity were also self-reported. RESULTS: The overall estimated prevalence of no reported dementia-related diagnosis for older Americans with a CICD was 91.4%(95%confidence interval (CI): 87.7%-94.1%). Persons with a CICD who identified as non-Hispanic black had a high prevalence of no reported dementia-related diagnosis (93.3%; CI: 89.8%-95.6%). The estimated prevalence of no reported dementia-related diagnosis was greater in males with a CICD (99.7%; CI: 99.6%-99.8%) than females (90.2%; CI: 85.6%-93.4%). Moreover, the estimated prevalence of no reported dementia-related diagnosis for non-high school graduates with a CICD was 93.5%(CI: 89.3%-96.1%), but 90.9%(CI: 84.7%-94.7%) for those with at least a high school education. CONCLUSION: Dementia screening should be encouraged during routine geriatric health assessments. Continued research that evaluates the utility of self-reported dementia-related measures is also warranted.

Rupture, reconstruction, and rehabilitation: A multi-disciplinary review of mechanisms for central nervous system adaptations following anterior cruciate ligament injury.

BACKGROUND: Despite surgical reconstruction and extensive rehabilitation, persistent quadriceps inhibition, gait asymmetry, and functional impairment remain prevalent in patients after anterior cruciate ligament (ACL) injury. A combination of reports have suggested underlying central nervous system adaptations in those after injury govern long-term neuromuscular impairments. The classic assumption has been to attribute neurophysiologic deficits to components of injury, but other factors across the continuum of care (e.g. surgery, perioperative analgesia, and rehabilitative strategies) have been largely overlooked. OBJECTIVE: This review provides a multidisciplinary perspective to 1) provide a narrative review of studies reporting neuroplasticity following ACL injury in order to inform clinicians of the current state of literature and 2) provide a mechanistic framework of neurophysiologic deficits with potential clinical implications across all phases of injury and recovery (injury, surgery, and rehabilitation) RESULTS: Studies using a variety of neurophysiologic modalities have demonstrated peripheral and central nervous system adaptations in those with prior ACL injury. Longitudinal investigations suggest neurophysiologic changes at spinal-reflexive and corticospinal pathways follow a unique timecourse across injury, surgery, and rehabilitation. CONCLUSION: Clinicians should consider the unique injury, surgery, anesthesia, and rehabilitation on central nervous system adaptations. Therapeutic strategies across the continuum of care may be beneficial to mitigate maladaptive neuroplasticity in those after ACL injury.

Voluntary wheel running with and without follistatin overexpression improves NMJ transmission but not motor unit loss in late life of C57BL/6J mice.

Sarcopenia, or pathological loss of muscle mass and strength during aging, is an important contributor to loss of physical function in older adults. Sarcopenia is a multifactorial syndrome associated with intrinsic muscle and upstream neurological dysfunction. Exercise is well-established as an effective intervention for sarcopenia, but less is known about the long-term neurobiological impact of exercise. The goals of this study were to investigate the effects of exercise, alone or in combination with follistatin (FST) overexpression (antagonist of myostatin), on neuromuscular junction transmission and motor unit numbers in mice between the age of 22 and 27 months, ages at which prior studies have demonstrated that some motor unit loss is already evident. C57BL/6J mice underwent baseline assessment and were randomized to housing with or without voluntary running wheels and injection with adeno-associated virus to overexpress FST or vehicle. Groups for comparison included sedentary and running with and without FST. Longitudinal assessments showed significantly increased muscle mass and contractility in the 'running plus FST' group, but running, with and without FST, showed no effect on motor unit degeneration. In contrast, running, with and without FST, demonstrated marked improvement of neuromuscular junction transmission stability.

Multiple measures of muscle function influence Sorensen Test performance in individuals with recurrent low back pain.

BACKGROUND: Sorensen Test time-to-task-failure (TTF) predicts several low back pain (LBP) clinical outcomes, including recurrence. Because the test is described as a measure of trunk extensor (TE) muscle endurance, LBP rehabilitation programs often emphasize endurance training, but the direct role of TE muscle function on Sorensen Test-TTF remains unclear. OBJECTIVE: To assess the discriminative and associative properties of multiple markers of isolated TE performance with regard to Sorensen Test-TTF in individuals with recurrent LBP. METHOD: Secondary analysis of baseline measures from participants in a registered (NCT02308189) trial (10 men; 20 women) was performed. Participants were classified by Sorensen Test-TTF as high, moderate or low risk for subsequent LBP episodes, and compared to determine if classification could discriminate differences in TE function. Correlations between Sorensen Test-TTF and isolated TE performance, anthropometrics and disability were investigated. RESULTS: Individuals at risk of subsequent LBP episodes had greater perceived disability and fat mass/TE strength ratios (P⩽ 0.05) than those not at risk. Modest, significant (r= 0.36-0.42, P⩽ 0.05) associations were found between Sorensen Test-TTF, TE endurance and fat mass/TE strength. Exploratory analyses suggested possible sex-specific differences related to Sorensen Test-TTF. CONCLUSIONS: Isolated TE muscle endurance is only one of several factors with similar influence on Sorensen Test-TFF, thus LBP rehabilitation strategies should consider other factors, including TE strength, anthropometrics and perceived disability.

Perspective: Pragmatic Exercise Recommendations for Older Adults: The Case for Emphasizing Resistance Training.

Optimal health benefits from exercise are achieved by meeting both aerobic and muscle strengthening guidelines, however, most older adults (OAs) do not exercise and the majority of those who do only perform one type of exercise. A pragmatic solution to this problem may be emphasizing a single exercise strategy that maximizes health benefits. The loss of muscle mass and strength at an accelerated rate are hallmarks of aging that, without intervention, eventually lead to physical disability and loss of independence. Additionally, OAs are at risk of developing several chronic diseases. As such, participating in activities that can maintain or increase muscle mass and strength, as well as decrease chronic disease risk, is essential for healthy aging. Unfortunately, there is a widely held belief that adaptations to aerobic and resistance exercise are independent of each other, requiring the participation of both types of exercise to achieve optimal health. However, we argue that this assertion is incorrect, and we discuss crossover adaptations of both aerobic and resistance exercise. Aerobic exercise can increase muscle mass and strength, though not consistently and may be limited to exercise that overloads a particular muscle group, such as stationary bicycling. In contrast, resistance exercise is effective at maintaining muscle health with increasing age, and also has significant effects on cardiovascular disease (CVD) risk factors, type 2 diabetes (T2D), cancer, and mortality. We posit that resistance exercise is the most effective standalone exercise strategy for improving overall health in OAs and should be emphasized in future guidelines.

Loss of Community-Dwelling Status Among Survivors of High-Acuity Emergency General Surgery Disease.

OBJECTIVES: To examine loss of community-dwelling status 9 months after hospitalization for high-acuity emergency general surgery (HA-EGS) disease among older Americans. DESIGN: Retrospective analysis of claims data. SETTING: US communities with Medicare beneficiaries. PARTICIPANTS: Medicare beneficiaries age 65 years or older hospitalized urgently/emergently between January 1, 2015, and March 31, 2015, with a principal diagnosis representing potential life or organ threat (necrotizing soft tissue infections, hernias with gangrene, ischemic enteritis, perforated viscus, toxic colitis or gastroenteritis, peritonitis, intra-abdominal hemorrhage) and an operation of interest on hospital days 1 or 2 (N = 3319). MEASUREMENTS: Demographic characteristics (age, race, and sex), comorbidities, principal diagnosis, complications, and index hospitalization disposition (died; discharged to skilled nursing facility [SNF], long-term acute care [LTAC], rehabilitation, hospice, home (with or without services), or acute care hospital; other) were measured. Survivors of index hospitalization were followed until December 31, 2015, on mortality and community-dwelling status (SNF/LTAC vs not). Descriptive statistics, Kaplan-Meier plots, and χ2 tests were used to describe and compare the cohort based on disposition. A multivariable logistic regression model, adjusted for age, sex, comorbidities, complications, and discharge disposition, determined independent predictors of loss of community-dwelling status at 9 months. RESULTS: A total of 2922 (88%) survived index hospitalization. Likelihood of discharge to home decreased with increasing age, baseline comorbidities, and in-hospital complications. Overall, 418 (14.3%) HA-EGS survivors died during the follow-up period. Among those alive at 9 months, 10.3% were no longer community dwelling. Initial discharge disposition to any location other than home and three or more surgical complications during index hospitalization were independent predictors of residing in a SNF/LTAC 9 months after surviving HA-EGS. CONCLUSION: Older Americans, known to prioritize living in the community, will experience substantial loss of independence due to HA-EGS. Long-term expectations after surviving HA-EGS must be framed from the perspective of the outcomes that older patients value the most. Further research is needed to examine the quality-of-life burden of EGS survivorship prospectively. J Am Geriatr Soc 67:2289-2297, 2019.

Factors associated with motoric cognitive risk syndrome among low-income older adults in Malaysia.

BACKGROUND: Motoric cognitive risk (MCR) syndrome is characterized by slow gait and memory complaints that could be used to predict an increased risk of dementia. This study aims to determine the MCR syndrome and its risk factors among low-income (B40) older adults in Malaysia. METHODS: Data from TUA cohort study involving 1366 older adults (aged 60 years and above) categorized as low-income were analysed, for risk of MCR syndrome based on defined criteria. Chi-square analysis and independent t test were employed to examine differences in socioeconomic, demographic, chronic diseases and lifestyle factors between MCR and non-MCR groups. Risk factors of MCR syndrome were determined using hierarchical logistic regression. RESULTS: A total of 3.4% of participants fulfilled the criteria of MCR syndrome. Majority of them were female (74.5%, p = 0.001), single/widow/widower/divorced (55.3%, p = 0.002), living in rural area (72.3%, p = 0.011), older age (72.74 ± 7.08 year old, p <  0.001) and had lower years of education (3.26 ± 2.91 years, p = 0.001) than non-MCR group. After adjustment for age, gender and years of education, participants living in rural area (Adjusted OR = 2.19, 95% CI = 1.10-4.35, p = 0.026), with obesity (Adjusted OR = 3.82, 95% CI = 1.70-8.57, p = 0.001), diabetes (Adjusted OR = 2.04, 95% CI = 1.01-4.11, p = 0.046), heart disease (Adjusted OR = 2.50, 95% CI = 1.00-6.20, p = 0.049) and cancer (Adjusted OR = 6.57, 95% CI = 1.18-36.65, p = 0.032) were associated with increased risk of MCR syndrome. CONCLUSION: Only 3.4% of older adults from low-income group were identified as having MCR syndrome. Women, those living in rural areas, had obesity, diabetes, heart disease and cancer were more likely to have MCR syndrome. Further investigation on MCR as a predementia syndrome will help in development of preventive strategies and interventions to reduce the growing burden of dementia, especially among individuals with low socioeconomic status.

Takotsubo Syndrome After Surgical and Nonsurgical Oral and Maxillofacial Events: Review of Published Cases.

PURPOSE: Takotsubo syndrome (TS) is an acute and potentially serious cardiac disorder that is often attributed to an exuberant catecholaminergic response to a severely physical or emotional event. As there is a paucity of information in the dental literature on TS, this article will provide an overview of this uncommon syndrome, including clinical presentation, demographic characteristics, etiopathogenesis, diagnosis, management, and recovery, particularly emphasizing its occurrence with oral and maxillofacial procedures. PATIENTS AND METHODS: A PubMed search with the keyword "takotsubo" for publications from 1991 through May 2018 yielded 3,778 articles. Case reports and case series of TS associated with surgical and nonsurgical procedures in the oral and maxillofacial region were reviewed. Other cases were identified using a defined search strategy. RESULTS: The literature search identified 28 documented episodes of TS that occurred with head and neck surgical procedures, mostly sinus, carotid, nasal, and cancer reconstruction surgical procedures, and notably, 3 cases occurred concurrently with dental extractions. In all of the featured patients, some degree of cardiovascular impairment developed and phenotypic overlap with acute occlusive coronary disease was shown. Most patients recovered within 2 weeks, and recovery in the remainder extended up to 3 months. CONCLUSIONS: On rare occasions, TS has been reported in association with oral and maxillofacial procedures. As stress appears to be a precipitating factor in the development of TS, perioperative efforts should be instituted to reduce an adrenergic cascade.

Skeletal muscle performance and ageing.

The world population is ageing rapidly. As society ages, the incidence of physical limitations is dramatically increasing, which reduces the quality of life and increases healthcare expenditures. In western society, ~30% of the population over 55 years is confronted with moderate or severe physical limitations. These physical limitations increase the risk of falls, institutionalization, co-morbidity, and premature death. An important cause of physical limitations is the age-related loss of skeletal muscle mass, also referred to as sarcopenia. Emerging evidence, however, clearly shows that the decline in skeletal muscle mass is not the sole contributor to the decline in physical performance. For instance, the loss of muscle strength is also a strong contributor to reduced physical performance in the elderly. In addition, there is ample data to suggest that motor coordination, excitation-contraction coupling, skeletal integrity, and other factors related to the nervous, muscular, and skeletal systems are critically important for physical performance in the elderly. To better understand the loss of skeletal muscle performance with ageing, we aim to provide a broad overview on the underlying mechanisms associated with elderly skeletal muscle performance. We start with a system level discussion and continue with a discussion on the influence of lifestyle, biological, and psychosocial factors on elderly skeletal muscle performance. Developing a broad understanding of the many factors affecting elderly skeletal muscle performance has major implications for scientists, clinicians, and health professionals who are developing therapeutic interventions aiming to enhance muscle function and/or prevent mobility and physical limitations and, as such, support healthy ageing.

Evolving concepts on the age-related changes in "muscle quality".

The deterioration of skeletal muscle with advancing age has long been anecdotally recognized and has been of scientific interest for more than 150 years. Over the past several decades, the scientific and medical communities have recognized that skeletal muscle dysfunction (e.g., muscle weakness, poor muscle coordination, etc.) is a debilitating and life-threatening condition in the elderly. For example, the age-associated loss of muscle strength is highly associated with both mortality and physical disability. It is well-accepted that voluntary muscle force production is not solely dependent upon muscle size, but rather results from a combination of neurologic and skeletal muscle factors, and that biologic properties of both of these systems are altered with aging. Accordingly, numerous scientists and clinicians have used the term "muscle quality" to describe the relationship between voluntary muscle strength and muscle size. In this review article, we discuss the age-associated changes in the neuromuscular system-starting at the level of the brain and proceeding down to the subcellular level of individual muscle fibers-that are potentially influential in the etiology of dynapenia (age-related loss of muscle strength and power).

Reduced physical activity increases intermuscular adipose tissue in healthy young adults.

BACKGROUND: Recent findings suggest that higher levels of intermuscular adipose tissue (IMAT) are associated with glucose dysregulation, lower levels of muscle strength, and a heightened risk of disability. Although several studies have described adaptations in muscle after reduced physical activity, the change in IMAT in healthy young adults is unknown. OBJECTIVE: The objective was to determine whether reduced lower limb activity alters IMAT in healthy young adults and to assess whether this change affects muscle strength loss. DESIGN: The subjects (6 men and 12 women aged 19-28 y) underwent a 4-wk control period, which was followed by 4 wk of unilateral lower limb suspension. Volumes of whole muscle, subcutaneous adipose tissue, and IMAT were assessed by using magnetic resonance imaging in the thigh and calf. Muscle strength was assessed during maximal voluntary isometric contractions. RESULTS: No changes were observed in the control period. Reduced physical activity decreased thigh and calf muscle volumes by 7.4% and 7.9% (P < 0.001), respectively; no significant change in subcutaneous adipose tissue was observed. Additionally, IMAT increased in both regions; the increase was larger in the calf (20%) than in the thigh (14.5%) (P