The pace and prognosis of peripheral sensory loss in advanced age: association with gait speed and falls

The prediction model of fall risk for the elderly based on gait analysis

INTRODUCTION

Early screening and identification are crucial for fall prevention, and developing a new method to predict fall risk in the elderly can address the current lack of objectivity in assessment tools.

METHODS

A total of 132 elderly individuals over 80 years old residing in some nursing homes in Shanghai were selected using a convenient sampling method. Fall history information was collected, and gait data during a 10-meter walk were recorded. Logistic regression was employed to establish the prediction model, and a nomogram was used to assess the importance of the indicators. The Bootstrap method was utilized for internal validation of the model, while the verification set was used for external validation. The predictive performance of the model was evaluated using the area under the ROC curve, calibration curve, and decision curve analysis (DCA) to assess clinical benefits.

RESULTS

The incidence of falls in the sample population was 36.4%. The Tinetti Gait and Balance Test (TGBT) score (OR = 0.832, 95% CI: 0.734,0.944), stride length (OR = 0.007, 95% CI: 0.000,0.104), difference in standing time (OR = 0.001, 95% CI: 0.000,0.742), and mean stride time (OR = 0.992, 95% CI:0.984,1.000) were identified as significant factors. The area under the ROC curve was 0.878 (95% CI: 0.805, 0.952), with a sensitivity of 0.935 and specificity of 0.726. The Brier score was 0.135, and the Hosmer-Lemeshow test (χ2 = 10.650, P = 0.222) indicated a good fit and calibration of the model.

CONCLUSION

The TGBT score, stride length, difference in standing time, and stride time are all protective factors associated with fall risk among the elderly. The developed risk prediction model demonstrates good discrimination and calibration, providing valuable insights for early screening and intervention in fall risk among older adults.

[Features of pharmacotherapy of vascular cognitive impairment in the elderly]

The problem of pharmacotherapy of elderly and senile people is currently extremely relevant due to the aging of the population and the increase in the prevalence of cardiovascular diseases. One of the most serious problems of the elderly is the development of cognitive decline due to cerebrovascular pathology. However, elderly patients often have a large number of comorbid diseases, which leads to difficulties in diagnosing and managing these patients, and often to the development of polypharmacy, which can lead to deterioration in functional status, cognitive impairment, adverse reactions and drug interactions. In addition, in elderly patients, there may be changes in pharmacokinetics and pharmacodynamics due to anatomical and physiological involutive processes. At the same time, the number of drugs whose clinical efficacy and tolerability were evaluated specifically in elderly and senile patients is relatively small. In a randomized clinical trial of sequential parenteral and oral therapy with Mexidol in patients with mild vascular cognitive impairment syndrome, a positive effect of this therapy on various domains (cognitive, emotional, autonomic, motor) of chronic cerebrovascular disease was confirmed compared with placebo, which allows us to recommend it for use in elderly and senile patients.

Six month lower-leg mechanical tactile sensory stimulation alters functional network connectivity associated with improved gait in older adults with peripheral neuropathy – A pilot study

Foot sole somatosensory impairment associated with peripheral neuropathy (PN) is prevalent and a strong independent risk factor for gait disturbance and falls in older adults. Walkasins, a lower-limb sensory prosthesis, has been shown to improve gait and mobility in people with PN by providing afferent input related to foot sole pressure distributions via lower-leg mechanical tactile stimulation. Given that gait and mobility are regulated by sensorimotor and cognitive brain networks, it is plausible improvements in gait and mobility from wearing the Walkasins may be associated with elicited neuroplastic changes in the brain. As such, this study aimed to examine changes in brain network connectivity after 26 weeks of daily use of the prosthesis among individuals with diagnosed PN and balance problems. In this exploratory investigation, assessments of participant characteristics, Functional Gait Assessment (FGA), and resting-state functional magnetic resonance imaging were completed at study baseline and 26 weeks follow-up. We found that among those who have completed the study (N = 8; mean age 73.7 years) we observed a five-point improvement in FGA performance as well as significant changes in network connectivity over the 26 weeks that were correlated with improved FGA performance. Specifically, greater improvement in FGA score over 26 weeks was associated with increased connectivity within the Default Mode Network (DMN; p < 0.01), the Somatosensory Network (SMN; p < 0.01), and the Frontoparietal Network (FPN; p < 0.01). FGA improvement was also correlated with increased connectivity between the DMN and the FPN (p < 0.01), and decreased connectivity between the SMN and both the FPN (p < 0.01) and cerebellum (p < 0.01). These findings suggest that 26 weeks of daily use of the Walkasins device may provide beneficial neural modulatory changes in brain network connectivity via the sensory replacement stimulation that are relevant to gait improvements among older adults with PN.

Extended effects of a wearable sensory prosthesis on gait, balance function and falls after 26 weeks of use in persons with peripheral neuropathy and high fall risk—The walk2Wellness trial

Background

We recently reported that individuals with impaired plantar sensation and high fall risk due to sensory peripheral neuropathy (PN) improved gait and balance function following 10 weeks of use of Walkasins^®, a wearable lower limb sensory prosthesis that provides directional specific mechanical tactile stimuli related to plantar pressure measurements during standing and walking (RxFunction Inc., Eden Prairie, MN, United States). Here, we report 26-week outcomes and compare pre- and in-study fall rates. We expected improvements in outcomes and reduced fall rates reported after 10 weeks of use to be sustained.

Materials and methods

Participants had clinically diagnosed PN with impaired plantar sensation, high fall risk (Functional Gait Assessment, FGA score < 23) and ability to sense tactile stimuli above the ankle at the location of the device. Additional outcomes included 10 m Gait Speed, Timed Up and Go (TUG), Four-Stage Balance Test, and self-reported outcomes, including Activities-Specific Balance Confidence scale and Vestibular Disorders Activities of Daily Living Scale. Participants tracked falls using a calendar.

Results

We assessed falls and self-reported outcomes from 44 individuals after 26 weeks of device use; 30 of them conducted in-person testing of clinical outcomes. Overall, improvements in clinical outcomes seen at 10 weeks of use remained sustained at 26 weeks with statistically significant increases compared to baseline seen in FGA scores (from 15.0 to 19.2), self-selected gait speed (from 0.89 to 0.97 m/s), and 4-Stage Balance Test (from 25.6 to 28.4 s), indicating a decrease in fall risk. Non-significant improvements were observed in TUG and fast gait speed. Overall, 39 falls were reported; 31 of them did not require medical treatment and four caused severe injury. Participants who reported falls over 6 months prior to the study had a 43% decrease in fall rate during the study as compared to self-report 6-month pre-study (11.8 vs. 6.7 falls/1000 patient days, respectively, p < 0.004), similar to the 46% decrease reported after 10 weeks of use.

Conclusion

A wearable sensory prosthesis can improve outcomes of gait and balance function and substantially decreases incidence of falls during long-term use. The sustained long-term benefits in clinical outcomes reported here lessen the likelihood that improvements are placebo effects.

Clinical trial registration

ClinicalTrials.gov, identifier #NCT03538756.

Exploring Shared Effects of Multisensory Impairment, Physical Dysfunction, and Cognitive Impairment on Physical Activity: An Observational Study in a National Sample

Multisensory, physical, and cognitive dysfunction share age-related physiologic disturbances and may have common health effects. We determined whether the effect of multisensory impairment on physical activity (PA) is explained by physical (timed up and go) or cognitive (Short Portable Mental Status Questionnaire) dysfunction. A National Social Life, Health, and Aging Project participant subset (n = 507) underwent objective sensory testing in 2005-2006 and wrist accelerometry in 2010-2011. We related multisensory impairment to PA using multivariate mixed-effects linear regression and compared the effect magnitude after adjusting for physical then cognitive dysfunction. Worse multisensory impairment predicted lower PA across three scales (Global Sensory Impairment: β = -0.04, 95% confidence interval [-0.07, -0.02]; Total Sensory Burden: β = -0.01, 95% confidence interval [-0.03, -0.003]; and Number of Impaired Senses: β = -0.02, 95% confidence interval [-0.04, -0.004]). Effects were similar after accounting for physical and cognitive dysfunction. Findings suggest that sensory, physical, and cognitive dysfunction have unique mechanisms underlying their PA effects.

Somatosensory impairment of the feet is associated with higher activation of prefrontal cortex during walking in older adults

BACKGROUND

Over-activation of prefrontal cortex during walking has been reported in older adults versus young adults. Heighted activity in prefrontal cortex suggests a shift toward an executive control strategy to control walking. A potential contributing factor is degraded functioning of pattern-generating locomotor circuits in the central nervous system that are important to walking coordination. Somatosensory information is a crucial input to these circuits, so age-related impairment of somatosensation would be expected to compromise the neural control of walking. The present study tested the hypothesis that poorer somatosensation in the feet of older adults will be associated with greater recruitment of the prefrontal cortex during walking. This study also examines the extent to which somatosensory function and prefrontal activity are associated with performance on walking and balance assessments.

METHODS

Forty seven older adults (age 74.6 ± 6.8 years; 32 female) participated in walking assessments (typical walking and obstacle negotiation) and Berg Balance Test. During walking, prefrontal activity was measured with functional near infrared spectroscopy (fNIRS). Participants also underwent somatosensory testing with Semmes-Weinstein monofilaments.

RESULTS

The primary findings is that worse somatosensory monofilament level was associated with greater prefrontal cortical activity during typical walking (r = 0.38, p = 0.008) and obstacle negotiation (r = 0.40, p = 0.006). For the obstacle negotiation task, greater prefrontal activity was associated with faster walking speed (p = 0.004). Poorer somatosensation was associated with slower typical walking speed (p = 0.07) and obstacles walking speed (p < 0.001), as well as poorer balance scores (p = 0.03).

CONCLUSIONS

The study findings are consistent with a compensation strategy of recruiting prefrontal/executive control resources to overcome loss of somatosensory input to the central nervous system. Future research should further establish the mechanisms by which somatosensory impairments are linked to the neural control and performance of walking tasks, as well as develop intervention approaches.

The Predictive Validity and Clinical Application of Stopping Elderly Accidents, Deaths & Injuries (STEADI) for Fall Risk Screening

Fall prevention is critical for older adults. Stopping Elderly Accidents, Deaths, and Injuries (STEADI) is a fall prevention initiative, promoted by the Center for Disease Control (CDC). The purpose of this review aims to discuss the predictive validity, improve the predictive validity of STEADI, and apply STEADI in clinical settings.

Risk Factors Related to Falling in Patients after Stroke

Background:

The aim of this study was to identify the risk factors associated with falling in post stroke patients.

Methods:

This retrospective case-control study included 561 neurology patients hospitalized for a stroke and divided into two groups: falling patients and non-falling patients. They referred to the Special Hospital for Cerebrovascular Diseases “Sveti Sava” in Belgrade, Serbia, from 2018–2019. Logistic regression analysis was applied to examine socio-economic factors associated with predictors of unmet healthcare needs.

Results:

A significant difference was seen in the length of hospitalization of falling patients compared to the non-falling (P<0.001). We established statistically significant differences in mental status (P<0.001), sensibility (P=0.016), depressed mood (P<0.001), early (P=0.001) and medium insomnia (P=0.042), psychomotor slowness (P=0.030), somatic anxiety (P=0.044) and memory (P<0.001).

Conclusion:

Cerebrovascular disease distribution and the degree of neurological deficit primarily altered mental status, which could be recognized as one of the more important predictors for falling after stroke. The identification of risk factors may be a first step toward the design of intervention programs for preventing a future fall among hospitalized stroke patients.

Identification of Optimal Foot Tactile Sensation Threshold for Detecting Fall Risk Among Community-Dwelling Older Adults

OBJECTIVE

Foot tactile sensitivity loss, commonly assessed by monofilaments, is a fall risk factor among older adults. The broadly used threshold of the monofilament for fall risk assessment in older adults is 5.07. However, this threshold originates from assessing foot ulceration risk in people with peripheral neuropathy. The primary purpose of this study was to identify the optimal filament size and its cutoff number of sensitive sites that can be used to best identify a high risk of falls in terms of the foot tactile sensitivity for community-dwelling older adults.

METHODS

In this cross-sectional study, the foot tactile sensitivity was assessed by a 6-piece Semmes-Weinstein monofilament kit at 9 sites per foot among 94 older adults, including 38 fallers and 56 nonfallers. The number of sensitive sites was determined for each monofilament size as the cutoff. Logistical regression analyses were used to determine the monofilament size and number of sensitive sites best able to differentiate fallers from nonfallers.

RESULTS

Fallers showed overall worse foot tactile sensory measurements than nonfallers. Logistical regression analyses identified 4.31 as the best monofilament size and 7 as the number of sensitive sites to differentiate fallers from nonfallers with an accuracy of 71.3%.

CONCLUSION

The 4.31 monofilament could be the best filament to detect the risk of falls among older adults in terms of tactile sensory loss. Inability to feel the pressure from the 4.31 filament at more than 7 sites could indicate a high risk of falls.

IMPACT

These findings could help physical therapists and other rehabilitation professionals improve decision making in detecting older adults with a high risk of falls, thus facilitating the effort of fall prevention in older adults.

Diagnosis and Management of Cognitive Concerns in the Oldest-Old

Purpose of review

The fastest-growing group of elderly individuals is the "oldest-old," usually defined as those age 85 years and above. These individuals account for much of the rapid increase in cases of dementing illness throughout the world but remain underrepresented in the body of literature on this topic. The aim of this review is first to outline the unique contributing factors and complications that must be considered by clinicians in evaluating an oldest-old individual with cognitive complaints. Secondly, the evidence for management of these cognitive concerns is reviewed.

Recent findings

In addition to well-established associations between impaired cognition and physical disability, falls, and frailty, there is now evidence that exercise performed decades earlier confers a cognitive benefit in the oldest-old. Moreover, though aggressive blood pressure control is critical earlier in life for prevention of strokes, renal disease, and other comorbidities, hypertension started after age 80 is in fact associated with a decreased risk of clinical dementia, carrying significant implications for the medical management of oldest-old individuals. The oldest-old are more likely to reside in care facilities, where social isolation might be exacerbated by a consistently lower rate of internet-connected device use. The COVID-19 pandemic has not only highlighted the increased mortality rate among the oldest-old but has also brought the increased social isolation in this group to the forte.

Summary

Differing from the "younger-old" in a number of respects, the oldest-old is a unique population not just in their vulnerability to cognitive disorders but also in the diagnostic challenges they can pose. The oldest-old are more likely to be afflicted by sensory deficits, physical disability, poor nutrition, frailty, and depression, which must be accounted for in the assessment of cognitive complaints as they may confound or complicate the presentation. Social isolation and institutionalization are also associated with impaired cognition, perhaps as sequelae, precipitants, or both. Ante-mortem diagnostic tools remain particularly limited among the oldest-old, especially given the likelihood of these individuals to have multiple co-occurring types of neuropathology, and the presence of neuropathology in those who remain cognitively intact. In addition to the symptomatic treatments indicated for patients of all ages with dementia, management of cognitive impairment in the oldest-old may be further optimized by use of assistive devices, augmentation of dietary protein, and liberalization of medication regimens for risk factors such as hypertension.

Older People's Experiences of Living with, Responding to and Managing Sensory Loss

(1) Background: Ageing is associated with a decline in sensory function (sight, hearing, taste, touch and smell), which play an important role in the maintenance of an older person’s health, independence and well-being. (2) Methods: This qualitative study obtained data through face-to-face semi-structured interviews with a convenience sample of thirteen community-dwelling adults 65 years and older. Themes were derived inductively, guided by semi-structured interviews. (3) Results: Twelve participants had two or more sensory impairments, mainly concurrent hearing and vision, which became apparent when a situation/individual alerted them to change/s occurring. They were less aware of impaired smell, taste and touch. Sensory changes impacted on important life functions, prompting many participants to take measured risks in maintaining their independence. Half (seven) of the participants lacked motivation to manage sensory function through goal-directed behaviour, taking remedial actions only when this was relevant to lifestyle preferences. (4) Conclusions: Internal and/or external triggers of sensory changes did not generally motivate remedial action. Health professionals can help to improve older people’s attention to sensory impairment by routinely discussing sensory function with them, screening for sensory changes and facilitating early intervention and support.

The Effects of a Wearable Sensory Prosthesis on Gait and Balance Function After 10 Weeks of Use in Persons With Peripheral Neuropathy and High Fall Risk - The walk2Wellness Trial

BACKGROUND

Sensory peripheral neuropathy (PN) is associated with gait, balance problems and high fall risk. The walk2Wellness trial investigates effects of long-term, home-based daily use of a wearable sensory prosthesis on gait function, balance, quality of life and fall rates in PN patients. The device (Walkasins®, RxFunction Inc., MN, United States) partially substitutes lost nerve function related to plantar sensation providing directional tactile cues reflecting plantar pressure measurements during standing and walking. We tested the null hypothesis that the Functional Gait Assessment (FGA) score would remain unchanged after 10 weeks of use.

METHODS

Participants had PN with lost plantar sensation, gait and balance problems, an FGA score < 23 (high fall risk), and ability to sense tactile stimuli above the ankle. Clinical outcomes included FGA, Gait Speed, Timed Up&Go (TUG) and 4-Stage Balance Test. Patient-reported outcomes included Activities-Specific Balance Confidence (ABC) scale, Vestibular Disorders Activities of Daily Living Scale, PROMIS participation and satisfaction scores, pain rating, and falls. Evaluations were performed at baseline and after 2, 6, and 10 weeks. Subjects were not made aware of changes in outcomes. No additional balance interventions were allowed.

RESULTS

Forty-five participants of 52 enrolled across four sites completed in-clinic assessments. FGA scores improved from 15.0 to 19.1 (p < 0.0001), normal and fast gait speed from 0.86 m/s to 0.95 m/s (p < 0.0001) and 1.24 m/s to 1.33 m/s (p = 0.002), respectively, and TUG from 13.8 s to 12.5 s (p = 0.012). Four-Stage Balance Test did not improve. Several patient-reported outcomes were normal at baseline and remained largely unchanged. Interestingly, subjects with baseline ABC scores lower than 67% (high fall risk cut-off) increased their ABC scores (49.9% to 59.3%, p = 0.01), whereas subjects with ABC scores above 67% showed a decrease (76.6% to 71.8%, p = 0.019). Subjects who reported falls in the prior 6 months (n = 25) showed a decrease in the number of fall-risk factors (5.1 to 4.3, p = 0.023) and a decrease in fall rate (13.8 to 7.4 falls/1000 days, p = 0.014). Four pre-study non-fallers (n = 20) fell during the 10 weeks.

CONCLUSION

A wearable sensory prosthesis presents a new way to treat gait and balance problems and manage falls in high fall-risk patients with PN.

TRIAL REGISTRATION

ClinicalTrials.gov (#NCT03538756).

Lower-limb hypopallesthesia: A risk factor for falls in cognitively intact non-diabetic older adults

Peripheral neuropathies (PN) in older adults often involve altered vibrational perception, i.e. hypopallesthesia. The main objective of this cross-sectional study was to determine whether age-related lower-limb hypopallesthesia is associated with a history of falls in cognitively intact non-diabetic older adults. The study population comprised 157 people (mean, 71.5 ± 3.8years, 45.3 % female, 19.7 % with a history of falls). Fallers more often exhibited hypopallesthesia than non-fallers (13.3 % versus 1.6 %, P = 0.04). Multiple logistic regression showed that hypopallesthesia (odds ratio (OR) = 19.5 [95 % confidence interval (CI): 2.7-143.7], P = 0.004) was associated with the history of falls in this sample of cognitively intact non-diabetic older adults.

Efficacy of an 8-Week Resistance Training Program in Older Adults: A Randomized Controlled Trial

Older adults are challenged with aging-related declines in skeletal muscle mass and function. Although exercise interventions of longer duration typically yield larger changes, shorter-term interventions may kick-start positive effects, allowing participants to begin engaging in more activity. This study aimed to determine whether 8 weeks of a resistance training program (Stay Strong, Stay Healthy [SSSH]) improved dynamic muscle strength, balance, flexibility, and sleep. Inactive adults aged ≥60 years were randomized into SSSH (n = 15), walking (WALK; n = 17), or control (CON; n = 14) groups. The SSSH and WALK groups met 2 times per week for 60 min. The participants completed pre/post general health, activity, and sleep questionnaires; DXA scans; and functional tasks. One-way repeated-measures multivariate analysis of variance was used to determine interactions and decomposed using repeated-measures analysis of variance. SSSH improved sit-to-stand performance, back scratch distance, and sleep quality and reported more auxiliary physical activity than WALK or CON (p < .05). Resistance training interventions in sedentary older adults can improve physical function and encourage additional activity in 8 weeks.