Effects of exercise on autonomic cardiovascular control in individuals with chronic, motor-complete spinal cord injury: an exploratory randomised clinical trial.

STUDY DESIGN: Secondary analysis of a clinical trial. OBJECTIVE: To assess the impact of 6 months of arm cycle ergometry training (ACET), or body weight-supported treadmill training (BWSTT), on autonomic cardiovascular responses to a laboratory sit-up test (SUT) in individuals with chronic (≥1-year post-injury) spinal cord injury (SCI). SETTING: Tertiary Rehabilitation Centre, Vancouver, Canada. METHODS: Sixteen individuals with motor-complete (American Spinal Injury Association Impairment Scale A-B) SCI between the fourth cervical and sixth thoracic spinal cord segments, aged 39 ± 11 years, were assessed. Participants were randomized to receive 72 sessions of moderate-to-vigorous intensity ACET (n = 8) or passive BWSTT (n = 8). Changes in mean arterial pressure (finger plethysmography), hemodynamics (Modelflow® method), and heart rate/heart rate variability (HR/HRV; electrocardiography) were measured in response to a  SUT before and after 6 months of exercise training. Spontaneous cardiovagal baroreflex sensitivity (cvBRS) was assessed using the sequence method. RESULTS: Neither ACET nor BWSTT impacted hemodynamic responses to SUT or the incidence of orthostatic hypotension (all P > 0.36). ACET increased HR (P < 0.01, ηp2 = 0.34) and high frequency (HF) power HRV responses (P < 0.01, ηp2 = 0.42) to SUT following 6 months of training while BWSTT did not. Consistent with this, cvBRS improved (P < 0.05, ηp2 = 0.16) only following ACET. Improvements in cvBRS were correlated with both the HR (r = 0.726, P < 0.0001) and HF power (r = -0.484, P < 0.01) responses to SUT. CONCLUSION: Six months of ACET, but not BWSTT, improved cardiovagal baroreflex control of HR but had no effect on BP responses to SUT in individuals with chronic, motor-complete SCI. SPONSORSHIP: Canadian Institutes of Health Research (CIHR) CLINICAL TRIAL REGISTRATION: NCT01718977.

Exercise and aerobic capacity in individuals with spinal cord injury: A systematic review with meta-analysis and meta-regression.

BACKGROUND: A low level of cardiorespiratory fitness [CRF; defined as peak oxygen uptake ([Formula: see text]O2peak) or peak power output (PPO)] is a widely reported consequence of spinal cord injury (SCI) and a major risk factor associated with chronic disease. However, CRF can be modified by exercise. This systematic review with meta-analysis and meta-regression aimed to assess whether certain SCI characteristics and/or specific exercise considerations are moderators of changes in CRF. METHODS AND FINDINGS: Databases (MEDLINE, EMBASE, CENTRAL, and Web of Science) were searched from inception to March 2023. A primary meta-analysis was conducted including randomised controlled trials (RCTs; exercise interventions lasting >2 weeks relative to control groups). A secondary meta-analysis pooled independent exercise interventions >2 weeks from longitudinal pre-post and RCT studies to explore whether subgroup differences in injury characteristics and/or exercise intervention parameters explained CRF changes. Further analyses included cohort, cross-sectional, and observational study designs. Outcome measures of interest were absolute (A[Formula: see text]O2peak) or relative [Formula: see text]O2peak (R[Formula: see text]O2peak), and/or PPO. Bias/quality was assessed via The Cochrane Risk of Bias 2 and the National Institute of Health Quality Assessment Tools. Certainty of the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Random effects models were used in all meta-analyses and meta-regressions. Of 21,020 identified records, 120 studies comprising 29 RCTs, 67 pre-post studies, 11 cohort, 7 cross-sectional, and 6 observational studies were included. The primary meta-analysis revealed significant improvements in A[Formula: see text]O2peak [0.16 (0.07, 0.25) L/min], R[Formula: see text]O2peak [2.9 (1.8, 3.9) mL/kg/min], and PPO [9 (5, 14) W] with exercise, relative to controls (p < 0.001). Ninety-six studies (117 independent exercise interventions comprising 1,331 adults with SCI) were included in the secondary, pooled meta-analysis which demonstrated significant increases in A[Formula: see text]O2peak [0.22 (0.17, 0.26) L/min], R[Formula: see text]O2peak [2.8 (2.2, 3.3) mL/kg/min], and PPO [11 (9, 13) W] (p < 0.001) following exercise interventions. There were subgroup differences for R[Formula: see text]O2peak based on exercise modality (p = 0.002) and intervention length (p = 0.01), but there were no differences for A[Formula: see text]O2peak. There were subgroup differences (p ≤ 0.018) for PPO based on time since injury, neurological level of injury, exercise modality, and frequency. The meta-regression found that studies with a higher mean age of participants were associated with smaller changes in A[Formula: see text]O2peak and R[Formula: see text]O2peak (p < 0.10). GRADE indicated a moderate level of certainty in the estimated effect for R[Formula: see text]O2peak, but low levels for A[Formula: see text]O2peak and PPO. This review may be limited by the small number of RCTs, which prevented a subgroup analysis within this specific study design. CONCLUSIONS: Our primary meta-analysis confirms that performing exercise >2 weeks results in significant improvements to A[Formula: see text]O2peak, R[Formula: see text]O2peak, and PPO in individuals with SCI. The pooled meta-analysis subgroup comparisons identified that exercise interventions lasting up to 12 weeks yield the greatest change in R[Formula: see text]O2peak. Upper-body aerobic exercise and resistance training also appear the most effective at improving R[Formula: see text]O2peak and PPO. Furthermore, acutely injured, individuals with paraplegia, exercising for ≥3 sessions/week will likely experience the greatest change in PPO. Ageing seemingly diminishes the adaptive CRF responses to exercise training in individuals with SCI. REGISTRATION: PROSPERO: CRD42018104342.

Post-processing Peak Oxygen Uptake Data Obtained During Cardiopulmonary Exercise Testing in Individuals With Spinal Cord Injury: A Scoping Review and Analysis of Different Post-processing Strategies.

OBJECTIVES: To review the evidence regarding the most common practices adopted with cardiopulmonary exercise testing (CPET) in individuals with spinal cord injury (SCI), with the following specific aims to (1) determine the most common averaging strategies of peak oxygen uptake (V̇o2peak), (2) review the endpoint criteria adopted to determine a valid V̇o2peak, and (3) investigate the effect of averaging strategies on V̇o2peak values in a convenience sample of individuals with SCI (between the fourth cervical and sixth thoracic spinal segments). DATA SOURCES: Searches for this scoping review were conducted in MEDLINE (PubMed), EMBASE, and Web Science. STUDY SELECTION: Studies were included if (1) were original research on humans published in English, (2) recruited adults with traumatic and non-traumatic SCI, and (3) V̇o2peak reported and measured directly during CPET to volitional exhaustion. Full-text review identified studies published before April 2021 for inclusion. DATA EXTRACTION: Extracted data included authors name, journal name, publication year, participant characteristics, and comprehensive information relevant to CPET. DATA SYNTHESIS: We extracted data from a total of 197 studies involving 4860 participants. We found that more than 50% of studies adopted a 30-s averaging strategy. A wide range of endpoint criteria were used to confirm the attainment of maximal effort. In the convenience sample of individuals with SCI (n=30), the mean V̇o2peak decreased as epoch (ie, time) lengths increased. Reported V̇o2peak values differed significantly (P<.001) between averaging strategies, with epoch length explaining 56% of the variability. CONCLUSIONS: The adoption of accepted and standardized methods for processing and analyzing CPET data are needed to ensure high-quality, reproducible research, and inform population-specific normative values for individuals with SCI.

Are local analgesics effective in reducing autonomic dysreflexia in individuals with spinal cord injury? A systematic review.

STUDY DESIGN: Systematic review. OBJECTIVES: To systematically review the evidence on the use of local analgesics, specifically lidocaine or bupivacaine, to prevent autonomic dysreflexia (AD) during iatrogenic procedures or bowel and bladder care routines in individuals with spinal cord injury (SCI). METHODS: A keyword search of MEDLINE, CINAHL, CENTRAL, Cochrane Reviews, PsycInfo, Embase, and Web of Science databases identified all English-language studies evaluating the efficacy of local analgesics in reducing AD. Included studies were either randomized controlled trials (RCTs) or quasi-experimental studies. Participants were adults with chronic SCI who received local analgesics prior to AD-triggering procedures or routines. Additionally, studies were required to report blood pressure values as an outcome. The methodology of this review followed the PRISMA checklist and was registered with PROSPERO (CRD42021219506). RESULTS: Four RCTs and two quasi-experimental studies met inclusion criteria. Results were narratively synthesized as meta-analysis was not possible due to heterogeneity across studies included in the review. All six studies administered lidocaine. Lidocaine was found to have a beneficial effect on AD in three studies, no effect in two studies and a detrimental effect in one study. CONCLUSIONS: Presently, RCTs and quasi-experimental studies on the use of lidocaine for reducing AD in individuals with SCI had small sample sizes and opposing findings. There is a strong need for definitive, well-monitored clinical trials with adequate sample sizes. Presently there is not enough compelling evidence to support or refute recommendations for the use of lidocaine from the AD management clinical practice guidelines.

Characterization of heart rate changes associated with autonomic dysreflexia during penile vibrostimulation and urodynamics.

STUDY DESIGN: Secondary data analysis. OBJECTIVES: To characterize autonomic dysreflexia (AD) associated heart rate (HR) changes during penile vibrostimulation (PVS) and urodynamic studies (UDS). SETTING: University-based laboratory. METHODS: We analyzed blood pressure (BP) and HR data, recorded continuously, from 21 individuals (4 females; median age 41 years [lower and upper quartile, 37; 47]; median time post-injury 18 years [7; 27]; all motor-complete spinal cord injury (SCI) except one; cervical SCI = 15, thoracic [T1-T6] SCI = 6), who underwent PVS (11/21) or UDS (10/21). RESULTS: Overall, 47 AD episodes were recorded (i.e. PVS = 37, UDS = 10), with at least one AD episode in each participant. At AD threshold, bradycardia was observed during PVS and UDS in 43% and 30%, respectively. At AD peak (i.e., maximum increase in systolic BP from baseline), bradycardia was observed during PVS and UDS in 65% and 50%, respectively. Tachycardia was detected at AD peak only once during UDS. Our study was limited by a small cohort of participants and the distribution of sex and injury characteristics. CONCLUSIONS: Our findings reveal that AD-associated HR changes during PVS and UDS appear to be related to the magnitude of systolic BP increases. Highly elevated systolic BP associated with bradycardia suggests the presence of severe AD. Therefore, we recommend cardiovascular monitoring (preferably with continuous beat-to-beat recordings) during PVS and UDS to detect AD early. Stopping assessments before systolic BP reaches dangerously elevated levels, could reduce the risk of life-threatening complications in this cohort.

Construct validity of the international standards to document remaining autonomic function after spinal cord injury (ISAFSCI) (1st edition).

STUDY DESIGN: Observational study. OBJECTIVES: To assess the construct validity of the International Standards to Document Remaining Autonomic Function after Spinal Cord Injury (ISAFSCI) (2012 1st Edition). SETTING: Two Canadian spinal cord injury (SCI) centers. METHODS: Data were collected between 2011-2014. Assessments included the ISAFSCI, standardized measures of autonomic function and a clinical examination. Construct validity of ISAFSCI was assessed by testing a priori hypotheses on expected ISAFSCI responses to standard measures (convergent hypotheses) and clinical variables (clinical hypotheses). RESULTS: Forty-nine participants with an average age of 45 ± 12 years were included, of which 42 (85.7%) were males, 37 (77.6%) had a neurological level of injury at or above T6, and 23 (46.9%) were assessed as having motor and sensory complete SCI. For the six General Autonomic Function component hypotheses, two hypotheses (1 clinical, 1 convergent) related to autonomic control of blood pressure and one clinical hypothesis for temperature regulation were statistically significant. In terms of the Lower Urinary Tract, Bowel and Sexual Function component of the ISAFSCI, all the hypotheses (5 convergent, 3 clinical) were statistically significant except for the hypotheses on female sexual items (2 convergent, 2 clinical), likely due to small sample size. CONCLUSION: The construct validity of ISAFSCI (2012 1st Edition) for the General Autonomic Function component was considered to be weak while it was much stronger for the Lower Urinary Tract, Bowel and Sexual Function component based on a priori hypotheses. These results can inform future psychometric studies of the ISAFSCI (2021 2nd Edition).

Epidural stimulation restores muscle synergies by modulating neural drives in participants with sensorimotor complete spinal cord injuries.

Multiple studies have corroborated the restoration of volitional motor control after motor-complete spinal cord injury (SCI) through the use of epidural spinal cord stimulation (eSCS), but rigorous quantitative descriptions of muscle coordination have been lacking. Six participants with chronic, motor and sensory complete SCI underwent a brain motor control assessment (BMCA) consisting of a set of structured motor tasks with and without eSCS. We investigated how muscle activity complexity and muscle synergies changed with and without stimulation. We performed this analysis to better characterize the impact of stimulation on neuromuscular control. We also recorded data from nine healthy participants as controls. Competition exists between the task origin and neural origin hypotheses underlying muscle synergies. The ability to restore motor control with eSCS in participants with motor and sensory complete SCI allows us to test whether changes in muscle synergies reflect a neural basis in the same task. Muscle activity complexity was computed with Higuchi Fractal Dimensional (HFD) analysis, and muscle synergies were estimated using non-negative matrix factorization (NNMF) in six participants with American Spinal Injury Association (ASIA) Impairment Score (AIS) A. We found that the complexity of muscle activity was immediately reduced by eSCS in the SCI participants. We also found that over the follow-up sessions, the muscle synergy structure of the SCI participants became more defined, and the number of synergies decreased over time, indicating improved coordination between muscle groups. Lastly, we found that the muscle synergies were restored with eSCS, supporting the neural hypothesis of muscle synergies. We conclude that eSCS restores muscle movements and muscle synergies that are distinct from those of healthy, able-bodied controls.

When the whole is greater than the sum of its parts: a scoping review of activity-based therapy paired with spinal cord stimulation following spinal cord injury.

Spinal cord injury (SCI) results in both motor and autonomic impairments, which can negatively affect independence and quality of life and increase morbidity and mortality. Despite emerging evidence supporting the benefits of activity-based training and spinal cord stimulation as two distinct interventions for sensorimotor and autonomic recovery, the combined effects of these modalities are currently uncertain. This scoping review evaluated the effectiveness of paired interventions (exercise + spinal neuromodulation) for improving sensorimotor and autonomic functions in individuals with SCI. Four electronic databases were searched for peer-reviewed manuscripts (Medline, Embase, CINAHL, and EI-compedex Engineering Village) and data were independently extracted by two reviewers using pre-established extraction tables. A total of 15 studies representing 79 participants were included in the review, of which 73% were conducted within the past 5 years. Only two of the studies were randomized controlled studies, while the other 13 studies were case or case-series designs. Compared with activity-based training alone, spinal cord stimulation combined with activity-based training improved walking and voluntary muscle activation, and augmented improvements in lower urinary tract, bowel, resting metabolic rate, peak oxygen consumption, and thermoregulatory function. Spinal neuromodulation in combination with use-dependent therapies may provide greater neurorecovery and induce long-term benefits for both motor and autonomic function beyond the capacity of traditional activity-based therapies. However, evidence for combinational approaches is limited and there is no consensus for outcome measures or optimal protocol parameters, including stimulation settings. Future large-scale randomized trials into paired interventions are warranted to further investigate these preliminary findings.

Common carotid artery responses to the cold-pressor test are impaired in individuals with cervical spinal cord injury.

Cervical spinal cord injury (SCI) leads to autonomic cardiovascular dysfunction that underlies the three- to fourfold elevated risk of cardiovascular disease in this population. Reduced common carotid artery (CCA) dilatory responsiveness during the cold-pressor test (CPT) is associated with greater cardiovascular disease risk and progression. The cardiovascular and CCA responses to the CPT may provide insight into cardiovascular autonomic dysfunction and cardiovascular disease risk in individuals with cervical SCI. Here, we used CPT to perturb the autonomic nervous system in 14 individuals with cervical SCI and 12 uninjured controls, while measuring cardiovascular responses and CCA diameter. The CCA diameter responses were 55% impaired in those with SCI compared with uninjured controls (P = 0.019). The CCA flow, velocity, and shear response to CPT were reduced in SCI by 100% (P < 0.001), 113% (P = 0.001), and 125% (P = 0.002), respectively. The association between mean arterial pressure and CCA dilation observed in uninjured individuals (r = 0.54, P = 0.004) was absent in the SCI group (r = 0.22, P = 0.217). Steady-state systolic blood pressure (P = 0.020), heart rate (P = 0.003), and cardiac contractility (P < 0.001) were reduced in those with cervical SCI, whereas total peripheral resistance was increased compared with uninjured controls (P = 0.042). Relative cerebral blood velocity responses to CPT were increased in the SCI group and reduced in controls (middle cerebral artery, P = 0.010; posterior cerebral artery, P = 0.026). The CCA and cardiovascular responsiveness to CPT are impaired in those with cervical SCI.NEW & NOTEWORTHY This is the first study demonstrating that CCA responses during CPT are suppressed in SCI. Specifically, CCA diameter, flow, velocity, and shear rate were reduced. The relationship between changes in MAP and CCA dilatation in response to CPT was absent in individuals with SCI, despite similar cardiovascular activation between SCI and uninjured controls. These findings support the notion of elevated cardiovascular disease risk in SCI and that the cardiovascular responses to environmental stimuli are impaired.

The microbiological and physical properties of catheters for intermittent catheterization: a systematic review on the impact of reuse and cleaning.

STUDY DESIGN: Systematic Review. OBJECTIVES: To review systematically the clinical evidence of the effectiveness of various intermittent catheter cleaning methods that have been proposed as methods to prepare catheters for reuse. METHODS: A keyword search in Medline, Excerpta Medica dataBASE, the Cumulative Index to Nursing and Allied Health Literature, Web of Science and Cochrane Central Register of Controlled Trials, was undertaken to identify all English, Russian and German language literature evaluating the effectiveness of various intermittent catheter cleaning methods. Studies selected for review included analytical experimental, prospective cohort and cross-sectional. Cleaning methods reviewed included heat-based sterilization, chemical cleaning solutions, mechanical abrasion, photocatalytic sterilization, and combined methods. RESULTS: Overall, 12 studies were included. Heat-based sterilization and mechanical abrasion methods were either not effective or damaged the physical properties of catheters. Two studies reported evidence that their chemical cleaning methods (i.e., soaked catheters in a 70% alcohol solution for 5 min or combined approach detergent wash followed by soaking in Milton sterilizing fluid also known as the Milton method) both preserved the structural integrity of their catheters and were bactericidal. CONCLUSIONS: Numerous cleaning methods resulted in the destruction of catheters. However, there are two reported cleaning methods, submersion for 5 min in 70% alcohol and the "Milton method", that eliminate bacterial colonization while leaving the physical properties of the catheters unchanged. While these cleaning methods are promising, each was published in just one study, therefore higher-powered / longitudinal studies confirming the safety and efficacy of these cleaning methods must be obtained before current clinical recommendations can be modified.

Heart rate changes associated with autonomic dysreflexia in daily life of individuals with chronic spinal cord injury.

STUDY DESIGN: Secondary data analysis. OBJECTIVE: To characterize heart rate (HR) changes during autonomic dysreflexia (AD) in daily life for individuals with chronic spinal cord injury (SCI). SETTING: University-based laboratory/community-based outpatient. METHODS: Cardiovascular data, previously collected during a 24-h ambulatory surveillance period in individuals with chronic SCI, were assessed. Any systolic blood pressure (SBP) increase ≥20 mmHg from baseline was identified and categorized into confirmed AD (i.e., diarized trigger), unknown (i.e., no diary entry), or unlikely AD (i.e., potential exertion driven SBP increase) groups. SBP-associated HR changes were categorized as unchanged, increased or decreased compared to baseline. RESULTS: Forty-five individuals [8 females, median age and time since injury of 43 years (lower and upper quartiles 36-50) and 17 years (6-23), respectively], were included for analysis. Overall, 797 episodes of SBP increase above AD threshold were identified and classified as confirmed (n = 250, 31.4%), unknown (n = 472, 59.2%) or unlikely (n = 75, 9.4%). The median number of episodes per individual within the 24-h period was 13 (8-28). HR-decrease/increase ratio was 3:1 for confirmed and unknown, and 1.5:1 for unlikely episodes. HR changes resulting in brady-/tachycardia were 34.4%/2.8% for confirmed, 39.6%/3.4% unknown, and 26.7%/9.3% for unlikely episodes, respectively. CONCLUSIONS: Our findings suggest that the majority of confirmed AD episodes are associated with a HR decrease. Using wearable-sensors-derived measures of physical activity in future studies could provide a more detailed characterization of HR changes during AD and improve AD identification.

The effects of active upper-limb versus passive lower-limb exercise on quality of life among individuals with motor-complete spinal cord injury.

STUDY DESIGN: Multi-centre randomized clinical trial. OBJECTIVES: (1) compare the effects of arm-cycle ergometry (ACET) and body weight supported treadmill training (BWSTT) on quality of life (QOL) and intermediary variables in individuals with spinal cord injury (SCI); (2) examine correlations between baseline measures, and changes in physical activity, QOL, and intermediaries. SETTING: Hospital-based research institutes (Vancouver, Toronto) and University-based exercise program (Hamilton). METHODS: 35 participants with motor-complete SCI above T6 completed baseline assessments of physical activity, life satisfaction, independence, autonomy, positive and negative affect, and pain. Twenty-eight participants were randomized to 72 sessions of ACET (n = 14) or BWSTT (n = 14) with measures repeated following 36 sessions, 72 sessions, and 6-months post-intervention. RESULTS: Neither intervention significantly impacted QOL. Pain was reduced in ACET compared to BWSTT (interaction effect p = 0.022) and was significantly less at 72 sessions vs. baseline in the ACET group (p = 0.009). At baseline, QOL was positively correlated with independence, autonomy, and positive affect and negatively correlated with negative affect (all p < 0.05). Following BWSTT, changes in moderate-vigorous physical activity correlated with changes in QOL (r = 0.87, p = 0.010). Following ACET, changes in autonomy and independence were positively correlated with changes in QOL (both r > 0.64, p < 0.048). CONCLUSIONS: Contrary to previous studies, there was no benefit of either intervention on measures of QOL. The social context of exercise may be important for improving QOL. However, individuals may benefit more from active (ACET) than passive (BWSTT) exercise modalities through reduced pain. Exercise interventions that improve autonomy and independence may lead to improvements in QOL.

The availability and quality of breastfeeding guidelines for women with spinal cord injury: a narrative review.

STUDY DESIGN: Narrative review. OBJECTIVES: To evaluate the availability and quality of breastfeeding guidelines for women with spinal cord injury (SCI). SETTING: International Collaboration on Repair Discoveries (ICORD), Department of Medicine, Vancouver, BC. METHODS: An environmental scan restricted to English language literature was performed to identify existing postpartum and breastfeeding guidelines. Guidelines were evaluated using a structured, validated tool (AGREE II) by 13 appraisers [medical/research experts (n = 10) and those with lived experience (n = 3)] from Vancouver and two international sites. Seven guidelines were evaluated across Domain 1 of the AGREE II tool to determine if they were applicable to mothers with SCI/physical disabilities. Domains 2 to 7 were evaluated if the guideline made mention of the SCI population. RESULTS: Of the seven guidelines evaluated, only one mentioned SCI (Postpartum Care in SCI from BC Women's Hospital). Other guidelines were excluded from further evaluation as they did not address the issue of breastfeeding in women with SCI. The overall scaled score for this guideline was 34.5%. There was significant variability between domains but no AGREE II domain scored greater than 50%, indicating substantial limitations. CONCLUSIONS: Current breastfeeding guidelines are not targeted to persons with SCI. The one guideline that made mention of women with SCI had significant global deficits. This highlights the importance of developing guidelines for health care providers focused specifically on women with SCI to support and optimize breastfeeding in this unique population for the benefit of mother and infant across the lifespan.

The safety of epidural spinal cord stimulation to restore function after spinal cord injury: post-surgical complications and incidence of cardiovascular events.

STUDY DESIGN: Cohort prospective study. OBJECTIVES: Epidural spinal cord stimulation (eSCS) improves volitional motor and autonomic function after spinal cord injury (SCI). While eSCS has an established history of safety for chronic pain, it remains unclear if eSCS in the SCI population presents the same risk profile. We aimed to assess safety and autonomic monitoring data for the first 14 participants in the E-STAND trial. SETTING: Hennepin County Medical Center, Minneapolis and Minneapolis Veterans Affairs Medical Center, Minnesota, USA. METHODS: Monthly follow-up visits assessed surgical and medical device-related safety outcomes as well as stimulation usage. Beat-by-beat blood pressure (BP) and continuous electrocardiogram data were collected during head-up tilt-table testing with and without eSCS. RESULTS: All participants had a motor-complete SCI. Mean (SD) age and time since injury were 38 (10) and 7 (5) years, respectively. There were no surgical complications but one device malfunction 4 months post implantation. Stimulation was applied for up to 23 h/day, across a broad range of parameters: frequency (18-700 Hz), pulse width (100-600 µs), and amplitude (0.4-17 mA), with no adverse events reported. Tilt-table testing with eSCS demonstrated no significant increases in the incidence of elevated systolic BP or a greater frequency of arrhythmias. CONCLUSIONS: eSCS to restore autonomic and volitional motor function following SCI has a similar safety profile as when used to treat chronic pain, despite the prevalence of significant comorbidities and the wide variety of stimulation parameters tested.

May I Have This Dance: A Case-Series on the Acute Cardiometabolic Demand of Wheelchair Dancing in Recreational Dancers with Spinal Cord Injury.

OBJECTIVES: This case-series investigated energy expenditure, cardiovascular responses, and psychosocial outcomes during two wheelchair dancing routines with different tempos. METHODS: Three individuals with chronic, non-traumatic spinal cord injuries [males, mean age 42 (13) years, C3-T12, AIS D, schwannoma=1, poliomyelitis=1, ependymoma=1] performed slow (rumba, 80 bpm) and fast (salsa, 170 bpm) wheelchair dance routines. Physiological [heart rate, blood pressure, relative oxygen consumption (VO2), metabolic task equivalent] and psychosocial parameters [ratings of perceived exertion, enjoyment and Brunel Mood Score] were measured pre, during, and post-dancing. RESULTS: All participants showed an elevation in heart rate and relative VO2 from rest to dancing with a subsequent decrease in these parameters post-dance for both routines. Relative to the slow dance routine, two out of three participants demonstrated greater heart rate, relative VO2, ratings of perceived exertion, and enjoyment during the fast dance routine. For all three participants, metabolic task equivalents ranged from 1.7-2.4 (slow) and 2.1-3.8 (fast), suggesting the intervention was of light to moderate intensity for slow and fast dance routines, respectively. Enjoyment ratings ranged from "quite a bit" to "extremely." No differences in Brunel mood subscales were observed. CONCLUSION: This case-series offers a preliminary understanding of the acute cardiometabolic and psychosocial responses to wheelchair dance routines of differing intensities per¬formed by individuals with spinal cord injury. Responsiveness observed among these participants suggests the potential use of wheelchair dance for promoting physical activity and improving psychological well-being.

Associations between left ventricular structure and function with cardiorespiratory fitness and body composition in individuals with cervical and upper thoracic spinal cord injury.

STUDY DESIGN: Cross-sectional. OBJECTIVE: It is known that left ventricular mass (LVM) and cardiorespiratory fitness (CRF) are associated to fat-free mass (FFM).  It is unknown if these factors associated with left ventricular (LV) structure and function outcomes in individuals with spinal cord injury (SCI). SETTING: University-based laboratory.Vancouver, BC, Canada. METHODS: Thirty-two individuals (aged 40 ± 11 years) with chronic, motor-complete SCI between the fourth cervical and sixth thoracic levels were recruited. Echocardiographic LV parameters and body composition were assessed at rest, as per the recommended guidelines for each technique. CRF was assessed during an incremental arm-cycle exercise test until volitional fatigue. The appropriate bivariate correlation coefficients [i.e., Pearson's (r) and Spearman's rank (Rs)] tests were used for normal and non-normal distributed variables, respectively. RESULTS: LV structure and function parameters were not associated with the indexed peak oxygen consumption (V̇O2peak) [i.e., relative to body weight or FFM] (Rs values ranged from -0.168 to 0.134, all P values > 0.223). The association between peak oxygen pulse and the resting echocardiographic-obtained SV was medium sized (Rs = 0.331, P = 0.069). The LVM associations with FFM and fat mass (FM) were large and small (r = 0.614, P < 0.001 and r = 0.266, P = 0.141, respectively). Associations of absolute V̇O2peak were medium- positive with FFM (Rs = 0.414, P = 0.021) but negative with FM (Rs = -0.332, P = 0.068). CONCLUSION: LV parameters measured at rest are not associated with V̇O2peak in individuals with cervical and upper-thoracic SCI. Given the observed associations between LVM and V̇O2peak with FFM, future studies may consider utilizing FFM for indexing cardiovascular measures following SCI.

Prevalence of self-reported complications associated with intermittent catheterization in wheelchair athletes with spinal cord injury.

STUDY DESIGN: Cross-sectional study. OBJECTIVES: To identify the prevalence of complications associated with intermittent catheterization in wheelchair athletes with spinal cord injury (SCI). SETTING: International and national sporting events. METHODS: A total 130 competitive wheelchair athletes living with SCI completed a self-reported questionnaire during international or national sporting events. The questionnaire collected information regarding demographics, injury characteristics, method of bladder emptying, and complications related to intermittent catheterization. RESULTS: Overall, 84% (109/130) of wheelchair athletes used intermittent catheterization. Within this group, 77% of athletes (84/109) experienced at least one complication associated with intermittent catheterization. Twenty-seven percent (29/109) sustained urethral injuries and 63% (69/109) had at least one episode of urinary tract infection during the last 12 months. Almost one-fourth of male athletes (22/95, 23%) had a history of inflammation / infection of genital organs associated with intermittent catheterization. CONCLUSIONS: Here we report a high prevalence of self-reported complications associated with intermittent catheterization in wheelchair athletes with SCI. Considering their potential impact on lower urinary tract function, athletic performance, and health, further studies are needed to assess the role of preventative strategies to reduce complications related to intermittent catheterization in wheelchair athletes with SCI. SPONSORSHIP: Coloplast Brazil and Instituto Lado a Lado pela Vida (a nongovernmental, nonprofit organization based in São Paulo) and Wellspect provided funding for this study.

Lifestyle modifications and pharmacological approaches to improve sexual function and satisfaction in men with spinal cord injury: a narrative review.

STUDY DESIGN: A narrative review describing various components of sexual dysfunction in men with spinal cord injury (SCI), as well as addressing potential therapeutic approaches. OBJECTIVES: Restoration of sexual function is considered one of the most important health priorities for individuals with SCI. The purpose of this review is to provide information regarding the factors that are less appreciated when considering changes to sexual function in men with SCI. We also propose therapeutic approaches, with a focus on lifestyle modifications, which have been shown to improve sexual function. METHODS: A literature search was performed and limited evidence for therapeutic approaches in individuals with SCI was supplemented by consistent findings from the able-bodied population. RESULTS: We evaluated the less addressed factors known to contribute to sexual dysfunction in men with SCI, including hormonal influences (i.e., testosterone deficiency, thyroid hormone, and cortisol), psychological factors (i.e., pain, fatigue, depression, and body image), and secondary SCI complications (i.e., urinary tract infection, pressure sores, and autonomic dysreflexia). To address these factors beyond standard medical treatments for sexual dysfunction, options include physical activity/exercise, diet, and specific medications for symptom relief (i.e., testosterone replacement therapy and selective serotonin reuptake inhibitors for depression). CONCLUSIONS: Physical activity's potential application, efficacy across multiple aspects of sexuality, and the lack of side effects, suggests that long-term exercise is a viable solution to directly or indirectly improve sexual function in males with SCI. Diet and supplemental medications may further promote body composition changes, which more broadly affect sexuality.

Spinal Cord Injury Impairs Cardiovascular Capacity in Elite Wheelchair Rugby Athletes.

OBJECTIVE: To examine differences in heart rate (HR) responses during international wheelchair rugby competition between athletes with and without a cervical spinal cord injury (SCI) and across standardized sport classifications. DESIGN: Observational study. SETTING: The 2015 Parapan American Games wheelchair rugby competition. PARTICIPANTS: Forty-three male athletes (31 ± 8 years) with a cervical SCI (n = 32) or tetraequivalent impairment (non-SCI, n = 11). MAIN OUTCOME MEASURES: Average and peak HR (HRavg and HRpeak, respectively). To characterize HR responses in accordance with an athletes' International Wheelchair Rugby Federation (IWRF) classification, we separated athletes into 3 groups: group I (IWRF classification 0.5-1.5, n = 15); group II (IWRF classification 2.0, n = 15); and group III (IWRF classification 2.5-3.5, n = 13). RESULTS: Athletes with SCI had lower HRavg (111 ± 14 bpm vs 155 ± 13 bpm) and HRpeak (133 ± 12 bpm vs 178 ± 13 bpm) compared with non-SCI (both P < 0.001). Average HR was higher in group III than in I (136 ± 25 bpm vs 115 ± 20 bpm, P = 0.045); however, SCI athletes showed no difference in HRavg or HRpeak between groups. Within group III, SCI athletes had lower HRavg (115 ± 6 bpm vs 160 ± 8 bpm) and HRpeak (135 ± 11 bpm vs 183 ± 11 bpm) than non-SCI athletes (both P < 0.001). CONCLUSIONS: This study is the first to demonstrate attenuated HR responses during competition in SCI compared with non-SCI athletes, likely due to injury to spinal autonomic pathways. Among athletes with SCI, IWRF classification was not related to differences in HR. Specific assessment of autonomic function after SCI may be able to predict HR during competition and consideration of autonomic impairments may improve the classification process.

Acute heat stress reduces biomarkers of endothelial activation but not macro- or microvascular dysfunction in cervical spinal cord injury.

Cardiovascular diseases (CVD) are highly prevalent in spinal cord injury (SCI), and peripheral vascular dysfunction might be a contributing factor. Recent evidence demonstrates that exposure to heat stress can improve vascular function and reduce the risk of CVD in uninjured populations. We therefore aimed to examine the extent of vascular dysfunction in SCI and the acute effects of passive heating. Fifteen participants with cervical SCI and 15 uninjured control (CON) participants underwent ultrasound assessments of vascular function and venous blood sampling for biomarkers of endothelial activation (i.e., CD62e+) and apoptosis (i.e., CD31+/42b-) before and after a 60-min exposure to lower limb hot water immersion (40°C). In SCI, macrovascular endothelial function was reduced in the brachial artery [SCI: 4.8 (3.2)% vs. CON: 7.6 (3.4)%, P = 0.04] but not the femoral artery [SCI: 3.7 (2.6)% vs. CON: 4.0 (2.1)%, P = 0.70]. Microvascular function, via reactive hyperemia, was ~40% lower in SCI versus CON in both the femoral and brachial arteries ( P < 0.01). Circulating concentrations of CD62e+ were elevated in SCI versus CON [SCI: 152 (106) microparticles/µl vs. CON: 58 (24) microparticles/µl, P < 0.05]. In response to heating, macrovascular and microvascular function remained unchanged, whereas increases (+83%) and decreases (-93%) in antegrade and retrograde shear rates, respectively, were associated with heat-induced reductions of CD62e+ concentrations in SCI to levels similar to CON ( P = 0.05). These data highlight the potential of acute heating to provide a safe and practical strategy to improve vascular function in SCI. The chronic effects of controlled heating warrant long-term testing. NEW & NOTEWORTHY Individuals with cervical level spinal cord injury exhibit selectively lower flow-mediated dilation in the brachial but not femoral artery, whereas peak reactive hyperemia was lower in both arteries compared with uninjured controls. After 60 min of lower limb hot water immersion, femoral artery blood flow and shear patterns were acutely improved in both groups. Elevated biomarkers of endothelial activation in the spinal cord injury group decreased with heating, but these biomarkers remained unchanged in controls.