Out of balance - Postural control in cancer patients before and after neurotoxic chemotherapy

Biofeedback-Based Proprioceptive Training to Improve Functional Prerequisites of Dragon Boating in Breast Cancer Survivors

Breast cancer (BC)-related sequelae drastically impact the psychophysical functioning and quality of life of affected women. Adapted physical activity (APA) has proved to effectively counteract these impairments in a non-medicalized framework. In particular, dragon boats are able to promote body functionality, social interaction, and quality of life in BC survivors, but the literature on specific motor gestures is scarce and practice is still based more on a re-educative perspective than a performative one. In this context, the present longitudinal study investigated the benefits of an adapted biofeedback-based sensorimotor training intervention on upper body functionality in a team of dragon ladies. The 8-week intervention was conceived as integrated dry workout sessions led by an APA kinesiologist and applied a novel sensorized proprioceptive device, such as a Libra board. Post-protocol evaluation revealed a significant improvement in bilateral upper limb mobility, core endurance, and trunk stability along with a distress decrease and quality of life enhancement through validated assessment tools. Our findings suggest that integrating biofeedback-based workout sessions can effectively promote upper body functionality in BC survivors practicing dragon boating. Furthermore, our innovative approach could help spread methodological hints able to boost exercise adherence in this target population, thus counteracting cancer recurrence while promoting overall well-being.

Identifying trajectories and predictors of chemotherapy-induced peripheral neuropathy symptoms, physical functioning, and falls across treatment and recovery in adults treated with neurotoxic chemotherapy: the PATTERN observational study protocol (NCT05790538)

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a debilitating and dose-limiting side effect of systemic cancer therapy. In many cancer survivors, CIPN persists after treatment ends and is associated with functional impairments, abnormal gait patterns, falls, and diminished quality of life. However, little is known regarding which patients are most likely to develop CIPN symptoms that impair mobility and increase fall risk, when this risk develops, or the optimal timing of early intervention efforts to mitigate the impact of CIPN on functioning and fall risk. This study will address these knowledge gaps by (1) characterizing trajectories of symptoms, functioning, and falls before, during, and after treatment in adults prescribed neurotoxic chemotherapy for cancer; and (2) determining the simplest set of predictors for identifying individuals at risk for CIPN-related functional decline and falls.

METHODS

We will enroll 200 participants into a prospective, observational study before initiating chemotherapy and up to 1 year after completing chemotherapy. Eligible participants are aged 40-85 years, diagnosed with stage I-III cancer, and scheduled to receive neurotoxic chemotherapy. We perform objective assessments of vibratory and touch sensation (biothesiometry, tuning fork, monofilament tests), standing and dynamic balance (quiet stance, Timed-Up-and-Go tests), and upper and lower extremity strength (handgrip dynamometry, 5-time repeated chair stand test) in the clinic at baseline, every 4-6 weeks during chemotherapy, and quarterly for 1 year post-chemotherapy. Participants wear devices that passively and continuously measure daily gait quality and physical activity for 1 week after each objective assessment and self-report symptoms (CIPN, insomnia, fatigue, dizziness, pain, cognition, anxiety, and depressive symptoms) and falls via weekly electronic surveys. We will use structural equation modeling, including growth mixture modeling, to examine patterns in trajectories of changes in symptoms, functioning, and falls associated with neurotoxic chemotherapy and then search for distinct risk profiles for CIPN.

DISCUSSION

Identifying simple, early predictors of functional decline and fall risk in adults with cancer receiving neurotoxic chemotherapy will help identify individuals who would benefit from early and targeted interventions to prevent CIPN-related falls and disability.

TRIAL REGISTRATION

This study was retrospectively registered with ClinicalTrials.gov (NCT05790538) on 3/30/2023.

The Influence of Anthropometric Variables and Filtering Frequency on Center of Pressure Data

Good postural control is considered to be a key component of an active lifestyle, and numerous studies have investigated the Center of Pressure (CoP) as a way of identifying motor deficits. However, the optimal frequency range for assessing CoP variables and the effect of filtering on the relationships between anthropometric variables and CoP are unclear. The aim of this work is to show the relationship between anthropometric variables and different ways of filtering the CoP data. CoP was measured in 221 healthy volunteers using a KISTLER force plate in four different test conditions, both mono and bipedal. The results show no significant changes in the existing correlations of the anthropometric variable values over different filter frequencies between 10 Hz and 13 Hz. Therefore, the findings with regard to anthropometric influences on CoP, with a reasonable but less than ideal filtering of the data, can be applied to other study settings.

Influence of chemotherapy on postural control and quality of life in women with gynaecological cancer: a protocol of a prospective observational study

INTRODUCTION

Chemotherapy-induced peripheral neuropathy is a frequent side effect of some chemotherapies that can cause postural control disorders and has a serious impact on quality of life (QoL). An enhanced understanding of postural control dysfunction could help build a systematic and accurate assessment as well as specific exercises to limit the impact on QoL. This study aims to assess the influence of chemotherapy on postural control and the QoL for women with gynaecological cancer.

METHODS AND ANALYSIS

This prospective observational study will include 37 participants with cancer treated using neurotoxic chemotherapy. Their postural control in various conditions (rigid and foam surfaces, eyes open and closed, with and without tendon vibration, and dual tasks), limits of stability, QoL and modified Total Neuropathy Score will be assessed. A linear mixed model will compare postural control pre-chemotherapy and post-chemotherapy.

ETHICS AND DISSEMINATION

This study was approved by an ethical review board in Geneva (CCER-2020-01639). The study findings will be disseminated through conference presentations and publications in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04692168.

Can physical exercise prevent chemotherapy-induced peripheral neuropathy in patients with cancer? A systematic review and meta-analysis

OBJECTIVE

This systematic review analyzed the effects of physical exercise programs in patients with cancer undergoing chemotherapy on Chemotherapy-induced Peripheral Neuropathy (CIPN) prevention.

DATA SOURCES

PubMed, Web of Science, Scopus, and Cochrane Library were searched for relevant studies published before December 2020. Additional references were identified by manual screening of the reference lists.

STUDY SELECTION

Based on the PICOS strategy, randomized controlled trials in which physical exercise was applied before or during chemotherapy to prevent or ameliorate CIPN were included.

DATA EXTRACTION

Two reviewers blinded and independent screened the articles, scored methodologic quality, and extracted data for analysis. The review was conducted and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement (PRISMA). Sensitivity and precision analysis databases was included. Risk of bias assessment and meta-analysis were conducted using the Cochrane tools.

DATA SYNTHESIS

Of 229 potentially relevant studies, eight randomized controlled trials were included and scored. They comprise a total of 618 patients with cancer. Medline and Scopus databases recorded the highest sensitivity. None of the studies achieved a "low" overall risk of bias. Four studies were included in meta-analysis for quality of life, and a significance standardized mean difference was found between groups from baseline of 14.62, 95% CI 6.03, 23.20, with a large effect size g= .83, 95% CI .48, 1.18) in favor to physical exercise program compared with usual care.

CONCLUSIONS

Physical exercise at the onset of chemotherapy has shown promising effects on the prevention of CIPN, specially improving quality of life.

Preventive effect of sensorimotor exercise and resistance training on chemotherapy-induced peripheral neuropathy: a randomised-controlled trial

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a common, unpleasant and usually long-lasting side effect of neurotoxic chemotherapeutic agents. This study aimed to investigate the preventive potential of sensorimotor- (SMT) and resistance training (RT) on CIPN.

METHODS

Patients (N = 170) were randomised to SMT, RT or usual care (UC). Both exercise groups trained 3×/week for a total of 105 min/week during neurotoxic chemotherapy (mean length: 20 weeks). Before and 3 weeks after neurotoxic chemotherapy, CIPN signs/symptoms were assessed via Total Neuropathy Score (TNSr; primary endpoint) and EORTC QLQ-CIPN15 questionnaire. In addition, balance (centre of pressure), muscle strength (isokinetic), quality of life (QoL, EORTC QLQ-C30) and relative chemotherapy dose intensity (RDI) were investigated. The follow-up period covered 6 months after the end of chemotherapy.

RESULTS

Intention-to-treat analyses (N = 159) revealed no differences regarding CIPN signs/symptoms. Exploratory per-protocol analyses (minimum training attendance rate 67%; N = 89) indicated that subjectively perceived sensory symptoms in the feet increased less during chemotherapy in the adherent exercisers (pooled group: SMT+RT) than in the UC group (-8.3 points (-16.1 to -0.4); P = 0.039, ES = 1.27). Furthermore, adherent exercisers received a higher RDI (96.6 ± 4.8 vs. 92.2 ± 9.4; P = 0.045), showed a better course of muscular strength (+20.8 Nm (11.2-30.4); P < 0.001, ES = 0.57) and QoL (+12.9 points (3.9-21.8); P = 0.005, ES = 0.64). During follow-up, CIPN signs/symptoms persisted in all groups.

CONCLUSIONS

This study demonstrates that SMT and/or RT alleviate subjectively perceived sensory CIPN symptoms in the feet and other clinically relevant cancer therapy-related outcomes, if an appropriate training stimulus is achieved.

CLINICAL TRIAL REGISTRATION

NCT02871284.

The Effects of Chemotherapy-Induced Polyneuropathy on Postural Balance

While cancer prevalence and survival rates are increasing, cancer-treatment-related functional decline and decreased quality of life are on the rise. Adverse side effects such as polyneuropathy are commonly associated with neurotoxic chemotherapeutic agents (i.e., taxanes or platinums) resulting in a decrease in postural balance and an increased risk for falls. This case report highlights an adult with polyneuropathy who received five months of chemotherapy treatment for a breast cancer diagnosis. Measurements included sensory integration of balance control using the BTrackS modified Clinical Test of Sensory Integration and Balance (mCTSIB) protocol and the Timed Up and Go (TUG) test. Compared to normative data, the participant demonstrated poor balance control in all conditions. Specifically, the results indicated proprioception was the most compromised component of balance control. The participant also demonstrated a slower TUG time compared to women of similar age. Our findings highlight the value of quantitative assessment of balance control following chemotherapy. More research would be needed to further support the tailored therapeutic approaches to prevent falls following chemotherapy treatment.

Type of exercise may influence postural adaptations in chemotherapy-induced peripheral neuropathy

OBJECTIVE

Traditional posturography measurements characterize postural instability in patients with chemotherapy-induced peripheral neuropathy (CIPN), while underlying postural control mechanisms remain unclear. Taking a model-based approach can yield insights into these mechanisms. This study's aim was to characterize the modifications in postural control of CIPN patients associated with exercise in relation to the postural behavior of healthy control participants (hCON) via an exploratory approach.

METHODS

Thirty-one CIPN patients were randomly assigned to two interventions (balance plus moderate endurance training vs. moderate endurance training only) and exercised twice per week over 12 weeks. Baseline data were compared to 36 matched hCONs. We recorded spontaneous sway and postural reactions to platform tilts using Optotrak and a Kistler force platform pre- and post-intervention. Data interpretation relied on a model-based parameter identification procedure.

RESULTS

Spontaneous sway amplitudes were larger and postural reactions smaller, with a relative phase advance, in our pre-intervention patients than the hCONs. Post-intervention, spontaneous sway, and postural reactions were reduced and the sensory-motor ratio larger in both groups, while the postural reaction timing differed between groups.

INTERPRETATION

The abnormally small postural reactions in CIPN patients before the intervention can be interpreted as the consequence of abnormally strong velocity control-a strategy modification that may serve as a prediction mechanism to compensate for the lack of timely and accurate proprioceptive signals. While both groups reduced postural sway and showed an adapted sensory-motor ratio post-intervention, the interventions seemed to trigger different velocity control strategies. This study emphasizes the need for taking a more differentiated perspective on intervention effects.

TRIAL REGISTRATION

German Clinical Trials Register (DRKS) number: DRKS00005419, prospectively registered on November 19, 2013.

Corneal nerve changes following treatment with neurotoxic anticancer drugs

Survival rates of cancer has improved with the development of anticancer drugs including systemic chemotherapeutic agents. However, long-lasting side effects could impact treated patients. Neurotoxic anticancer drugs are specific agents which cause chemotherapy-induced peripheral neuropathy (CIPN), a debilitating condition that severely deteriorates quality of life of cancer patients and survivors. The ocular surface is also prone to neurotoxicity but investigation into the effects of neurotoxic chemotherapy on the ocular surface has been more limited compared to other systemic etiologies such as diabetes. There is also no standardized protocol for CIPN diagnosis with an absence of a reliable, objective method of observing nerve damage structurally. As the cornea is the most densely innervated region of the body, researchers have started to focus on corneal neuropathic changes that are associated with neurotoxic chemotherapy treatment. In-vivo corneal confocal microscopy enables rapid and objective structural imaging of ocular surface microscopic structures such as corneal nerves, while esthesiometers provide means of functional assessment by examining corneal sensitivity. The current article explores the current guidelines and gaps in our knowledge of CIPN diagnosis and the potential role of in-vivo corneal confocal microscopy as a diagnostic or prognostic tool. Corneal neuropathic changes with neurotoxic anticancer drugs from animal research progressing through to human clinical studies are also discussed, with a focus on how these data inform our understanding of CIPN.

Chemotherapy-induced peripheral neuropathy: longitudinal analysis of predictors for postural control

Impaired postural control is often observed in response to neurotoxic chemotherapy. However, potential explanatory factors other than chemotherapy-induced peripheral neuropathy (CIPN) have not been adequately considered to date due to primarily cross-sectional study designs. Our objective was to comprehensively analyze postural control during and after neurotoxic chemotherapy, and to identify potential CIPN-independent predictors for its impairment. Postural control and CIPN symptoms (EORTC QLQ-CIPN20) were longitudinally assessed before, during and three weeks after neurotoxic chemotherapy, and in three and six months follow-up examinations (N = 54). The influence of peripheral nerve function as determined by nerve conduction studies (NCS: compound motor action potentials (CMAP) and sensory action potentials (SNAP)), physical activity, and muscle strength on the change in postural control during and after chemotherapy was analyzed by multiple linear regression adjusted for age and body mass index. Postural control, CIPN signs/symptoms, and CMAP/SNAP amplitudes significantly deteriorated during chemotherapy (p < .01). During follow-up, patients recovered from postural instabilities (p < .01), whereas CIPN signs/symptoms and pathologic NCS findings persisted compared to baseline (p < .001). The regression model showed that low CMAP and high SNAP amplitudes at baseline predicted impairment of postural control during but not after chemotherapy. Hence, pre-therapeutically disturbed somatosensory inputs may induce adaptive processes that have compensatory effects and allow recovery of postural control while CIPN signs/symptoms and pathologic peripheral nerve function persist. Baseline NCS findings in cancer patients who receive neurotoxic chemotherapy thus might assist in delineating individual CIPN risk profiles more precisely to which specific exercise intervention programs could be tailor-made.

A review of movement disorders in chemotherapy-induced neurotoxicity

Chemotherapy agents used in the standard treatments for many types of cancer are neurotoxic and can lead to lasting sensory and motor symptoms that compromise day-to-day movement functions in cancer survivors. To date, the details of movement disorders associated with chemotherapy are known largely through self-reported symptoms and functional limitations. There are few quantitative studies of specific movement deficits, limiting our understanding of dysfunction, as well as effective assessments and interventions. The aim of this narrative review is to consolidate the current understanding of sensorimotor disabilities based on quantitative measures in cancer survivors who received chemotherapy. We performed literature searches on PubMed and found 32 relevant movement studies. We categorized these studies into three themes based on the movement deficits investigated: (1) balance and postural control; (2) gait function; (3) upper limb function. This literature suggests that cancer survivors have increased postural sway, more conservative gait patterns, and suboptimal hand function compared to healthy individuals. More studies are needed that use objective measures of sensorimotor function to better characterize movement disabilities and investigate the underlying causes, as required for developing targeted assessments and interventions. By updating our understanding of movement impairments in this population, we identify significant gaps in knowledge that will help guide the direction of future research.