Postural control is associated with cognition and fear of falling in patients with multiple sclerosis

Effect of melatonin intake on postural balance, functional mobility and fall risk in persons with multiple sclerosis: a pilot study

AIM

To assess the safety and the effect of a nocturnal melatonin (MEL) ingestion on postural balance, functional mobility and fall risk the following morning in adults with multiple sclerosis (MS).

METHODS

Fourteen adults with relapsing-remitting MS (RR-MS) (28.36 ± 6.81 years) were evaluated before and after nocturnal ingestion of MEL (6 mg) or placebo (PLA). Evaluations included a posturographic test of static bipedal postural balance with dual-task in eyes open (EO) and eyes closed conditions, and a clinical test of unipedal balance. The physical performance tests were: Timed Up and Go test (TUGT) (mobility), Four Square Step Test (FSST) (fall risk), and Timed 25-foot walk test (T25FWT) (walking speed). Cognitive performance [Montreal Cognitive Assessment (MoCA) and Simple Reaction Time (SRT) tests] and sleep quality [Spiegel's sleep questionnaire (SSQ)] were also assessed.

RESULTS

In EO condition, MEL decreased the posturographic parameters [center of pressure (CoP) sway area (CoPAr), CoP path length (CoPL) and CoPL in the mediolateral axis (CoPLX)] more than PLA by 15.82% (p = 0.0006), 12.48% (p  = 0.0004) and 14.25% (p = 0.0002), respectively. Durations of TUGT and FSST decreased following MEL session more than the PLA one by 14.52% (p = 0.017) and 19.85% (p = 0.0006), respectively. MEL increased the unipedal stance time, SSQ and MoCA scores more than PLA by 49.81% (p = 0.04), 32.21% (p = 0.004) and 11.87% (p = 0.008), respectively.

CONCLUSION

This pilot study showed that acute nocturnal MEL ingestion seems to be safe for enhancing postural balance, fun mobility and fall risk in RR-MS adults probably through improving sleep quality and cognitive function.

Fear of falling and common symptoms of multiple sclerosis: Physical function, cognition, fatigue, depression, and sleep - A systematic review

BACKGROUND

Fear of falling (FOF) is a common concern among persons with multiple sclerosis (MS) and affects the performance of their daily living activities. Falls may result in FOF, leading to worsening of symptoms of MS, physical deconditioning, and exposure to future falls. This may trigger a vicious cycle between FOF and falls. A better understanding of the relationship between FOF and symptoms of MS may be helpful to develop a conceptual model to guide fall prevention interventions.

OBJECTIVE

To synthesize the correlational and predictive relationships between FOF and common symptoms of MS.

METHODS

Databases including PubMed, Embase, Web of Science, Scopus, CINHAL, PsycINFO, and SPORTDiscuss were searched from inception to October 2023. Studies examining correlations and/or predictions between FOF and common MS symptoms that include measures of gait, postural control, fatigue, cognition, pain, sleep, depression, and anxiety were identified by two independent reviewers. Both reviewers also conducted the methodological quality assessment of the included studies.

RESULTS

Twenty-three studies with a total of 2819 participants were included in the review. Correlational findings indicated that increased FOF was significantly associated with greater walking deficits (lower gait speed, smaller steps), reduced mobility, and poorer balance. Increased FOF was also significantly correlated with higher cognitive impairments, more fatigue, sleep disturbances, and depression. Decreased gait parameters, reduced balance, lower physical functions, cognitive impairments, and sleep deficits were found as significant predictors of increased FOF.

CONCLUSION

Evidence indicates significant correlational and bidirectional predictive relationships exist between FOF and common MS symptoms. A comprehensive conceptual framework accounting for the interaction between FOF and MS symptoms is needed to develop effective falls prevention strategies.

Association between cognitive impairment and motor dysfunction among patients with multiple sclerosis: a cross-sectional study

BACKGROUND

Previous studies have shown that there is a relationship between cognitive impairment (CI) and motor dysfunction (MD) in neurological diseases, such as Alzheimer's and Parkinson's disease. However, there whether CI and MD are associated in patients with multiple sclerosis (MS) is unknown. Here we studied the association between CI and MD in patients with MS and examined if muscle weakness or incoordination, balance impairment, gait abnormalities, and/or increased fall risk are indicators of CI in patients with MS.

METHODS

Seventy patients with MS were included in this cross-sectional study. Cognitive impairment was assessed using the Montreal Cognitive Assessment Scale (MoCA), muscle strength using a hand-held dynamometer, and balance, gait, and fall risk assessment using the Tinetti scale. Motor coordination was assessed using the timed rapid alternating movement test for the upper extremity and the timed alternate heel-to-knee test for the lower extremity.

RESULTS

There was a significant association between CI and motor coordination, balance, gait, and risk of fall (p < 0.005) but not muscle strength. Stepwise multiple linear regression showed that 22.7% of the variance in the MoCA was predicted by the fall risk and incoordination of the upper extremities in the MS population.

CONCLUSIONS

CI is significantly associated with motor incoordination, balance impairment, gait abnormality, and increased fall risk. Furthermore, the risk of fall and upper extremity incoordination appeared to be best indicators of CI in patients with MS.

Cognition and proprioception in persons with multiple sclerosis and healthy controls: Nascent findings

BACKGROUND

Although proprioception and cognitive dysfunction are commonly associated with balance impairment and fall risk in persons with multiple sclerosis (MS), the relationship between cognitive functioning and a quantitative measure of proprioception has not been examined in MS.

OBJECTIVE

The primary goals of this study were to determine differences in vibratory sensation, a proxy measure of proprioception between persons with MS and healthy controls, examine relationships between cognition and vibration sensation, and determine the contribution of cognitive function and demographics to vibratory sensation between persons with MS and healthy controls.

METHODS

One hundred and twenty-two individuals with MS, aged 20-60, with Expanded Disability Status Scale (EDSS) scores ≤5.5 and 48 healthy controls completed reaction time testing, the Stroop test and lower extremity vibratory sensation.

RESULTS

Persons with MS performed significantly worse than controls on measures of vibratory sensation (p = 0.001), two-choice reaction time (p = 0.018), and Stroop Incongruent (p < 0.001) Relative Incongruent Score (RIS) (p = 0.047). In MS, average vibration was significantly related to age (p = 0.002), sex (p = 0.038), disease severity (EDSS; p < 0.001), years since diagnosis (p = 0.016), and Stroop Word (p = 0.041). A model with demographics; including age and disease severity, two-choice reaction time, and RIS explained 33.2% of the variance vibratory sensation in persons with MS.

CONCLUSIONS

These results provide early evidence for the relation between cognitive functioning and proprioception in persons with MS and add to prior work linking cognitive functioning, postural control and falls in persons with MS. This work provides a basis for future studies combining quantitative measures of proprioception and cognitive and postural control assessment to improve fall prediction.

Role of Cervical Spinal Magnetic Stimulation in Improving Posture and Functional Ambulation of Patients with Relapsing Remitting Multiple Sclerosis

Balance impairment is one of the hallmarks of early MS. Proprioceptive deficit was found to be one of the main causes of this imbalance. The cervical enlargement has a strong proprioceptive system, with its projections to the reticular formation and the central pattern generators, helping in rhythmic pattern generation and alternate leg movements. Repetitive trans-spinal magnetic stimulation (rTSMS) is a noninvasive technique, which can trigger massive proprioceptive afferents. Therefore, it has the potential of improving proprioceptive deficits and motor control. Objective. To determine the effectiveness of repetitive cervical magnetic stimulation in improving functional ambulation of patients with relapsing remitting multiple sclerosis (RRMS). Design. Prospective sequential clinical trial. Setting. University and academic hospital. Participants. A total of 32 participants ( $N=32$ ) with RRMS. Interventions. Outpatient rehabilitation. The 32 patients received 10 sessions over two weeks of 20 Hz cervical spinal magnetic stimulation (SMS). Both groups were assessed at baseline, after 2 weeks, then one month later. Patients were enrolled as a control group at first and received Sham SMS, and then a wash out period of one month was done for all the patients, followed by a baseline assessment. Second, the same 32 patients rejoined as the active group, which received real magnetic stimulation. Both groups performed an intensive physical therapy program with the spinal magnetic stimulation. Main Outcome Measures. Extended Disability status score (EDSS), Timed up and Go test (TUG), Mini-Best test, dynamic posturography sensory organization composite score, and motor composite score. Results. Thirty-two RRMS patients with EDSS range from 1.5 to 6. They showed statistically significant difference between active and control groups in Mini-Best test score. We divided our patients according to EDSS into 3 subgroups: (a) mild: ≤2.5, (b) moderate: 3-5.5, and (c) severe: ≥6. Mild cases showed significant differences in EDSS score, TUG test, Mini-Best test, and dynamic posturography sensory composite scale. The effect size between the different patient subgroups was also measured and showed highly significant improvements in all measured parameters among our mild patients, indicating that this subgroup could be the best responders to cervical repetitive high-frequency magnetic stimulation. Moderate cases showed highly significant improvement in TUG score and Mini-Best test and significant change in EDSS score and the dynamic posturography sensory composite score. Severe cases showed only significant improvements in TUG, Mini-Best test, and sensory composite score. Conclusion. Cervical repetitive magnetic stimulation can help improve balance and functional ambulation and decreases the risk of falls in RRMS patients, especially in the mild, low disability cases.

Fear of falling and falls in people with multiple sclerosis: A literature review

INTRODUCTION

Fear of falling (FOF) is a widespread problem affecting about 60% of people with multiple sclerosis (pwMS). Inflammatory lesions in the brain that are caused by the disease result in gait deficits and increase the risk of fall. Falls induce fear of falling and trigger a vicious circle, which in turn increases the likelihood of falling. Objective of this review was to provide an overview of existing research on the effects of FOF and therapy options in multiple sclerosis.

METHODS

A systematic search at Web of Science and PubMed was conducted. The search included the terms (fear of falling) OR (concern about falling) OR (fall anxiety) AND (multiple sclerosis).

RESULTS

In included studies, FOF was measured by different instruments. The Falls Efficacy Scale-International (FES-I) was the most frequently used instrument for pwMS. Patients with a higher FOF score fell more frequently, had lower walking speed, shorter stride length, larger ellipse sway area and a more severe disability. At present, therapeutic offers exist mainly in the field of physiotherapy. For reducing FOF, assisted vibration (d_z = 0.68), VR (d_z =0.87) and bicycle training (d_z = 1.23) were the most effective methods.

CONCLUSION

It is advisable to develop therapies that incorporate both physical and psychological aspects in neurorehabilitation, like in a cognitive behavioral therapy. Moreover, FOF monitoring should be integrated into the clinical routine.

Clinical features and physical performance in multiple sclerosis patients with and without cognitive impairment: a cross-sectional study

The factors associated with cognitive functions in patients with multiple sclerosis (PwMS) are not yet clear. The aims of this study were (1) to compare clinical features and physical performance in healthy controls, and PwMS with and without cognitive impairment, and (2) to determine the relationship between cognitive domains and demographics characteristics, clinical features and physical performance in PwMS. A total of 112 PwMS and 25 healthy controls participated in this study. Cognitive functions were evaluated by Brief Repeatable Battery of Neuropsychological Tests (BRB-N). Based on cognitive performances by BRB-N, PwMS were divided into two groups as MS patients with impaired (MS-I, n: 57) and with normal (MS-N, n: 55) cognitive functions. For clinical features, fatigue, mood and sleep quality were evaluated by the Fatigue Impact Scale, Beck's Depression Inventory, Pittsburgh Sleep Quality Index, respectively. For physical performances, balance and walking capacity were evaluated by posturography and Six-Minute Walking Test, respectively. The results showed that the education years, postural stability and walking capacity in MS-N and healthy controls were higher than in MS-I (P < 0.05). In addition, visuospatial memory was correlated with both postural stability under all sensory conditions and walking capacity; verbal memory was correlated with education years, postural stability on eyes closed-foam surface and walking capacity; verbal fluency was correlated with only walking capacity; information processing speed was correlated with education years, postural stability under all sensory conditions and walking capacity (P < 0.001). This study suggests that the interventions that aim to improve physical performance might protect and even improve cognitive functions in PwMS.

Use of a Short Version of the Activities-specific Balance Confidence Scale in Multiple Sclerosis

BACKGROUND

Multiple sclerosis (MS) is a neurologic disease that results in balance and mobility impairments that are associated with elevated fall risk. One common patient-reported outcome measure of balance is the 16-item Activities-specific Balance Confidence (ABC) scale. The ABC scale is valid and reliable in assessing balance confidence in people with MS. However, a shorter, six-question version of the ABC scale, the ABC-6 scale, has been proposed to save time in a clinical setting. Thus, we assessed the convergent validity and internal consistency reliability of the ABC-6 scale in people with MS.

METHODS

A total of 221 participants were included in this secondary analysis to compare the ABC-6 scale with the ABC scale. Convergent validity and internal consistency reliability were applied to participants based on fall history and physiological fall risk.

RESULTS

Statistical analysis indicated a main effect of group of the ABC and ABC-6 scales (P < .001). Both scales showed good to very good internal consistency (Cronbach α range, 0.832-0.975) and good reliability (intraclass correlation coefficient score range, 0.888-0.941). Furthermore, both versions had moderate convergent validity. Sensitivity ranged from 30% to 97%, and specificity ranged from 64% to 100% across groups tested.

CONCLUSIONS

The ABC and ABC-6 scales demonstrated good internal consistency reliability and moderate convergent validity in predicting balance confidence in people with MS. However, poor sensitivity of both versions in distinguishing between MS groups at risk for falls may call into question the usefulness of this self-report measure.

Balance Changes in Patients With Relapsing-Remitting Multiple Sclerosis: A Pilot Study Comparing the Dynamics of the Relapse and Remitting Phases

Aims: To compare balance changes over time during the relapse phase of relapsing-remitting multiple sclerosis (RRMS) with balance control during the remitting phase.

Methods: Balance control during stance and gait tasks of 24 remitting-phase patients (mean age 43.7 ± 10.5, 15 women, mean EDSS at baseline 2.45 ± 1.01) was examined every 3 months over 9 months and compared to that of nine relapsing patients (age 42.0 ± 12.7, all women, mean EDSS at relapse onset 3.11 ± 0.96) examined at relapse onset and 3 months later. Balance was also compared to that of 40 healthy controls (HCs) (age 39.7 ± 12.6, 25 women). Balance control was measured as lower-trunk sway angles with body-worn gyroscopes. Expanded Disability Status Scale scores (EDSS) were used to monitor, clinically, disease progression.

Results: Remitting-phase patients showed more unstable stance balance control than HCs (p < 0.04) with no worsening over the observation period of 9 months. Gait balance control was normal (p > 0.06). Relapsing patients had stance balance control significantly worse at onset compared to remitting-phase patients and HCs (p < 0.04). Gait tasks showed a significant decrease of gait speed and trunk sway in relapsing patients (p = 0.018) compatible with having increased gait instability at normal speeds. Improvement to levels of remitting patients generally took longer than 3 months. Balance and EDSS scores were correlated for remitting but not for relapse patients.

Conclusions: Balance in remitting RRMS patients does not change significantly over 9 months and correlated well with EDSS scores. Our results indicate that balance control is a useful measure to assess recovery after a relapse, particularly in patients with unchanged EDSS scores. Based on our results, balance could be considered as additional measurement to assess recovery after a relapse, particularly in patients with unchanged EDSS.

Neural correlates of gait variability in people with multiple sclerosis with fall history

BACKGROUND AND PURPOSE

The aim was to investigate the association between step time variability and related brain structures in accordance with fall status in people with multiple sclerosis (PwMS).

METHODS

The study included 225 PwMS. Whole-brain magnetic resonance imaging was performed with a high-resolution 3.0 T magnetic resonance scanner in addition to volumetric analysis based on 3D T1-weighted images using the FreeSurfer image analysis suite. Step time variability was measured with an electronic walkway. Participants were defined as 'fallers' (at least two falls during the previous year) and 'non-fallers'.

RESULTS

In all, 105 PwMS were defined as fallers and had a greater step time variability compared to non-fallers [5.6% (SD = 3.4) vs. 3.4% (SD = 1.5); P = 0.001]. MS fallers exhibited a reduced volume in the left caudate and both cerebellum hemispheres compared to non-fallers. On using a linear regression analysis no association was found between gait variability and related brain structures in the total cohort and the non-fallers group. However, the analysis found an association between the left hippocampus and left putamen volumes with step time variability in the faller group: P = 0.031, 0.048, respectively, controlling for total cranial volume, walking speed, disability, age and gender. Nevertheless, according to the hierarchical regression model, the contribution of these brain measures to predict gait variability was relatively small compared to walking speed.

CONCLUSIONS

An association between low left hippocampal, putamen volumes and step time variability was found in PwMS with a history of falls, suggesting that brain structural characteristics may be related to falls and increased gait variability in PwMS.

Cerebellum and cognition in multiple sclerosis: the fall status matters

Cerebellar volume has been linked with cognitive performances in MS; however, the association in terms of fall status has never been compared. Therefore, the objective of the current study was to compare cognitive performance with cerebellar volume between MS fallers and non-fallers. The cross-sectional study included 140 PwMS (96 women). MRI volumetric analysis was based on the FreeSurfer image analysis suite. Volumes of the cerebellar gray and white matter were identified as the region of interest. Cognitive function included scores obtained from a computerized cognitive battery of tests. The sample was divided into fallers and non-fallers. MS fallers demonstrated a lower global cognitive performance and reduced gray and white matter cerebellar volumes compared to non-fallers. A significant association was found between total gray and white matter cerebellar volume and visual spatial subdomain (P value = 0.044 and 0.032, respectively) in the non-fallers group. The association remained significant after controlling for the total cranial volume and neurological disability (P value = 0.026 and 0.047, respectively). A relationship was found between the visual spatial score and the left gray matter cerebellum volume; R² = 0.44, P value = 0.021. We believe that a unique relationship exists between the cerebellum structure and cognitive processing according to fall history in PwMS and should be considered when investigating the association between brain functioning and cognitive performances in MS.