Cardiometabolic risk clustering in spinal cord injury: results of exploratory factor analysis

Taking risk to heart: An evaluation of cardiometabolic risk and screening guideline adherence in outpatients with spinal cord injury

OBJECTIVES

To evaluate cardiometabolic disease (CMD) in outpatients with spinal cord injury/disease (SCI/D). The study aims were to (1) estimate the prevalence of CMD risk factors in a cohort of Canadian adults with SCI/D; (2) assess whether the frequency of CMD screening aligns with evidence-based guidelines; and (3) gain a preliminary understanding of the barriers to CMD screening and/or treatment within a rehabilitation program setting.

DESIGN

Quality improvement initiative involving chart review extracting the presence of and frequency of screening for four CMD risk factors (obesity, hypertension, dyslipidemia, diabetes mellitus). Values were compared to evidence-based guidelines for CMD risk identification and management. Root cause analysis and focused interviews were conducted with clinic staff to identify barriers.

SETTING

Academic, tertiary rehabilitation hospital.

PARTICIPANTS

Consecutive outpatients with SCI/D from October 2020 to December 2021 (n = 73).

RESULTS

43.8% of outpatients sampled had established CMD (≥3 risk factors) and 94.5% had at least one risk factor. Obesity was the most prevalent (82.2%), followed by dyslipidemia (71.7%), hypertension (46.5%), and diabetes mellitus (34.8%). Hypertension and obesity screening were completed at 14.3% and 10.4% of appointments. The frequency of dyslipidemia and diabetes mellitus screening could not be determined. Eighteen barriers to timely CMD screening and treatment intensification were identified.

CONCLUSIONS

The prevalence of CMD risk factors in outpatients with SCI/D was high. While approximately two of every five outpatients had established CMD, adherence to screening guidelines was poor. These findings reinforce the need for strategies to improve screening and reduce preventable harm from CMD in this vulnerable population.

Treatment of obesity in spinal cord injury with tirzepatide: a case report

INTRODUCTION

Individuals with spinal cord injury (SCI) experience alterations in metabolism that result in increased central obesity, insulin resistance, and dyslipidemia placing them at elevated risk for developing cardiometabolic disease (CMD). Increased exercise and dietary modifications are the primary interventions for preventing CMD. However, people with SCI face unique challenges that prevent them from increasing their physical activity and easily modifying their nutritional intake. Tirzepatide is a medication that has been approved by the Food and Drug Administration to be used in conjunction with lifestyle changes to treat obesity in adults with type 2 diabetes mellitus.

CASE PRESENTATION

A male in his 40's with C6 American Spinal Injury Association Impairment Scale B SCI 15 years prior with a body mass index of 32 presented to his primary care provider for treatment of obesity. He previously worked with multiple dietitians and increased his physical activity to lose weight. Despite these interventions, he was unable to reduce his weight. He was started on tirzepatide. After 3 months of treatment, he lost 31 pounds and saw improvements in his lipid profile. The only adverse effect reported was heartburn.

DISCUSSION

The metabolic dysfunction associated with SCI and barriers to adequate exercise for weight loss place individuals with SCI at increased risk for obesity and developing CMD. Tirzepatide may be an effective adjunct therapy to lifestyle interventions to help prevent CMD in those with SCI. Further research is indicated to examine the long-term efficacy, benefits, and adverse effects that may be associated with tirzepatide.

Reducing endocrine metabolic disease risk in adults with chronic spinal cord injury: strategic activities conducted by the Ontario-Quebec RIISC team

PURPOSE

The Rehabilitation Interventions for Individuals with a Spinal Cord Injury in the Community (RIISC) team aimed to develop and evaluate innovative rehabilitation interventions to identify endocrine metabolic disease (EMD) risk, intending to reduce the frequency and severity of EMD related morbidity and mortality among adults living with chronic spinal cord injury or disease (SCI/D).

MATERIALS AND METHODS

An interprovincial team from Ontario and Quebec reviewed available EMD literature and evidence syntheses and completed an inventory of health services, policies and practices in SCI/D care. The review outcomes were combined with expert opinion to create an EMD risk model to inform health service transformation.

RESULTS

EMD risk and mortality are highly prevalent among adults with chronic SCI/D. In stark contrast, few rehabilitation interventions target EMD outcomes. The modelled solution proposes: 1) abandoning single-disease paradigms and examining a holistic perspective of the individual's EMD risk, and 2) developing and disseminating practice-based research approaches in outpatient community settings.

CONCLUSIONS

RIISC model adoption could accelerate EMD care optimization, and ultimately inform the design of large-scale longitudinal pragmatic trials likely to improve health outcomes. Linking the RIISC team activities to economic evaluations and policy deliverables will strengthen the relevance and impact among policymakers, health care providers and patients.

Cardiometabolic risk factor clustering in persons with spinal cord injury: A principal component analysis approach

CONTEXT/OBJECTIVE

To identify cardiometabolic (CM) measurements that cluster to confer increased cardiovascular disease (CVD) risk using principal component analysis (PCA) in a cohort of chronic spinal cord injury (SCI) and healthy non-SCI individuals.

APPROACH

A cross-sectional study was performed in ninety-eight non-ambulatory men with chronic SCI and fifty-one healthy non-SCI individuals (ambulatory comparison group). Fasting blood samples were obtained for the following CM biomarkers: lipid, lipoprotein particle, fasting glucose and insulin concentrations, leptin, adiponectin, and markers of inflammation. Total and central adiposity [total body fat (TBF) percent and visceral adipose tissue (VAT) percent, respectively] were obtained by dual x-ray absorptiometry (DXA). A PCA was used to identify the CM outcome measurements that cluster to confer CVD risk in SCI and non-SCI cohorts.

RESULTS

Using PCA, six factor-components (FC) were extracted, explaining 77% and 82% of the total variance in the SCI and non-SCI cohorts, respectively. In both groups, FC-1 was primarily composed of lipoprotein particle concentration variables. TBF and VAT were included in FC-2 in the SCI group, but not the non-SCI group. In the SCI cohort, logistic regression analysis results revealed that for every unit increase in the FC-1 standardized score generated from the statistical software during the PCA, there is a 216% increased risk of MetS (P = 0.001), a 209% increased risk of a 10-yr. FRS ≥ 10% (P = 0.001), and a 92% increase in the risk of HOMA2-IR ≥ 2.05 (P = 0.01).

CONCLUSION

Application of PCA identified 6-FC models for the SCI and non-SCI groups. The clustering of variables into the respective models varied considerably between the cohorts, indicating that CM outcomes may play a differential role on their conferring CVD-risk in individuals with chronic SCI.

Innervation of adipocytes is limited in mouse perivascular adipose tissue

Perivascular adipose tissue (PVAT) regulates vascular tone by releasing anticontractile factors. These anticontractile factors are driven by processes downstream of adipocyte stimulation by norepinephrine; however, whether norepinephrine originates from neural innervation or other sources is unknown. The goal of this study was to test the hypothesis that neurons innervating PVAT provide the adrenergic drive to stimulate adipocytes in aortic and mesenteric perivascular adipose tissue (aPVAT and mPVAT), and white adipose tissue (WAT). Healthy male and female mice (8-13 wk) were used in all experiments. Expression of genes associated with synaptic transmission were quantified by qPCR and adipocyte activity in response to neurotransmitters and neuron depolarization was assessed in AdipoqCre+;GCaMP5g-tdTf/WT mice. Immunostaining, tissue clearing, and transgenic reporter lines were used to assess anatomical relationships between nerves and adipocytes. Although synaptic transmission component genes are expressed in adipose tissues (aPVAT, mPVAT, and WAT), strong nerve stimulation with electrical field stimulation does not significantly trigger calcium responses in adipocytes. However, norepinephrine consistently elicits strong calcium responses in adipocytes from all adipose tissues studied. Bethanechol induces minimal adipocyte responses. Imaging neural innervation using various techniques reveals that nerve fibers primarily run alongside blood vessels and rarely branch into the adipose tissue. Although nerve fibers are associated with blood vessels in adipose tissue, they demonstrate limited anatomical and functional interactions with adjacent adipocytes, challenging the concept of classical innervation. These findings dispute the significant involvement of neural input in regulating PVAT adipocyte function and emphasize alternative mechanisms governing adrenergic-driven anticontractile functions of PVAT.NEW & NOTEWORTHY This study challenges prevailing views on neural innervation in perivascular adipose tissue (PVAT) and its role in adrenergic-driven anticontractile effects on vasculature. Contrary to existing paradigms, limited anatomical and functional connections were found between PVAT nerve fibers and adipocytes, underscoring the importance of exploring alternative mechanistic pathways. Understanding the mechanisms involved in PVAT's anticontractile effects is critical for developing potential therapeutic interventions against dysregulated vascular tone, hypertension, and cardiovascular disease.

Physical and emotional consequences of excess weight as experienced by individuals with spinal cord injuries

CONTEXT/OBJECTIVE

Excess weight has the potential to carry a substantial physical and emotional burden. A better understanding of perceived consequences of excess weight may facilitate the development of patient-centered programs and interventions to promote weight management efforts in persons with spinal cord injury (SCI). The study objective was to describe consequences of excess weight from the personal perspectives of individuals with SCI.

DESIGN

Descriptive qualitative design using in-depth semi-structured interviews and thematic analysis.

SETTING

Veterans Health Administration (VHA) SCI System of Care.

PARTICIPANTS

Individuals with SCI (n-33).

OUTCOME MEASURES

Key themes from thematic analysis.

RESULTS

Participants were male (61%), ranged from 29 to 84 years of age, and about half had tetraplegia (55%). Five themes were identified that demonstrate negative consequences of excess weight experienced by individuals with SCI, including: (1) physical health conditions (including chronic conditions and SCI secondary conditions), (2) physical symptoms (such as pain, discomfort, and fatigue), (3) movement challenges, (4) appearance-related concerns, and (5) emotional impacts.

CONCLUSIONS

Carrying excess weight is concerning to individuals with SCI and in terms of consequences such onset or exacerbation of chronic conditions, SCI secondary conditions, physical symptoms, e.g. pain, movement impairment (including hampered mobility, difficult transfers and self-care), image/appearance concerns (e.g. body image, clothing misfit), and negative emotions (e.g. unhappy, sad, depressed). Our findings may inform SCI healthcare providers about the consequences of excess weight as experienced by individuals with SCI, highlighting what matters most to persons with SCI and guiding a patient-centered approach to weight management in this population.

Assessing the efficacy of duration and intensity prescription for physical activity in mitigating cardiometabolic risk after spinal cord injury

PURPOSE OF REVIEW

Spinal cord injury (SCI) heightens susceptibility to cardiometabolic risk (CMR), predisposing individuals to cardiovascular disease. This monograph aims to assess the optimal duration and intensity of physical activity (PA) for managing CMR factors, particularly obesity, after SCI and provide modality-specific PA durations for optimal energy expenditure.

RECENT FINDINGS

PA guidelines recommend at least 150 min/week of moderate-intensity activity. However, non-SCI literature supports the effectiveness of engaging in vigorous-intensity PA (≥6 METs) and dedicating 250-300 min/week (≈2000 kcal/week) to reduce CMR factors. Engaging in this volume of PA has shown a dose-response relationship, wherein increased activity results in decreased obesity and other CMR factors in persons without SCI.

SUMMARY

To optimize cardiometabolic health, individuals with SCI require a longer duration and higher intensity of PA to achieve energy expenditures comparable to individuals without SCI. Therefore, individuals with SCI who can engage in or approach vigorous-intensity PA should prioritize doing so for at least 150 min/wk. At the same time, those unable to reach such intensities should engage in at least 250-300 min/week of PA at a challenging yet comfortable intensity, aiming to achieve an optimal intensity level based on their abilities. Given the potential to decrease CMR after SCI, increasing PA duration and intensity merits careful consideration in future SCI PA directives.

Burden of Cardiovascular Risk in Individuals With Spinal Cord Injury and Its Association With Rehabilitation Outcomes: Results From the Swiss Spinal Cord Injury Cohort

OBJECTIVES

The aims of the study are to determine the cardiovascular risk burden rehabilitation discharge and to explore the association between recovery during rehabilitation and cardiovascular disease risk profile.

METHODS

We included adults without cardiovascular disease admitted for rehabilitation. We evaluated rehabilitation outcomes on admission and discharge. Cardiovascular disease risk profile was assessed by Framingham risk score, high-density lipoprotein, and fasting glucose level.

RESULTS

We analyzed data from 706 participants (69.6% men) with a median age of 53.5 yrs. The median time since injury was 14 days, and the admission length was 5.2 months. Majority had paraplegia (53.3%) and motor incomplete injury (53.7%). One third of the cohort had high cardiovascular risk profile before discharge. At discharge, poorer anthropometric measures were associated with higher Framingham risk score and lower high-density lipoprotein levels. Individuals with higher forced vital capacity (>2.72 l) and peak expiratory flow (>3.4 l/min) had 0.16 mmol/l and 0.14 mmol/l higher high-density lipoprotein compared with those with lower respiratory function, respectively. Individuals with higher mobility score (>12.5) and functional independence score (>74) had 0.21 and 0.18 mmol/l higher high-density lipoprotein compared with those with lower scores.

CONCLUSIONS

There is high cardiometabolic syndrome burden and cardiovascular disease risk profile upon rehabilitation discharge. Higher respiratory function, mobility, and overall independence were associated with better cardiovascular disease risk profile, although with study design limitations and short follow-up. Future studies should explore whether rehabilitation outcomes could be used to prioritize screening.

TO CLAIM CME CREDITS

Complete the self-assessment activity and evaluation online at http://www.physiatry.org/JournalCME.

CME OBJECTIVES

Upon reading this journal article, the reader is expected to: (1) Determine the burden of cardiometabolic disease in the early phase of spinal cord injury (SCI); (2) Differentiate the proposed SCI cutoff for high-risk obesity from the able-bodied population; and (3) Increase physicians' acuity for detecting cardiometabolic disease in their practice.

LEVEL

Advanced.

ACCREDITATION

The Association of Academic Physiatrists is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.The Association of Academic Physiatrists designates this Journal-based CME activity for a maximum of 1.0 AMA PRA Category 1 Credit(s) ™. Physicians should only claim credit commensurate with the extent of their participation in the activity.

The Physiology of Neurogenic Obesity: Lessons from Spinal Cord Injury Research

BACKGROUND

A spinal cord injury (SCI) from trauma or disease impairs sensorimotor pathways in somatic and autonomic divisions of the nervous system, affecting multiple body systems. Improved medical practices have increased survivability and life expectancy after SCI, allowing for the development of extensive metabolic comorbidities and profound changes in body composition that culminate in prevalent obesity.

SUMMARY

Obesity is the most common cardiometabolic component risk in people living with SCI, with a diagnostic body mass index cutoff of 22 kg/m2 to account for a phenotype of high adiposity and low lean mass. The metameric organization of specific divisions of the nervous system results in level-dependent pathology, with resulting sympathetic decentralization altering physiological functions such as lipolysis, hepatic lipoprotein metabolism, dietary fat absorption, and neuroendocrine signaling. In this manner, SCI provides a unique opportunity to study in vivo the "neurogenic" components of certain pathologies that otherwise are not readily observable in other populations. We discuss the unique physiology of neurogenic obesity after SCI, including the altered functions mentioned above as well as structural changes such as reduced skeletal muscle and bone mass and increased lipid deposition in the adipose tissue, skeletal muscle, bone marrow, and liver.

KEY MESSAGE

The study of neurogenic obesity after SCI gives us a unique neurological perspective on the physiology of obesity. The lessons learned from this field can guide future research and advancements to inform the study of obesity in persons with and without SCI.

Similar fat and carbohydrate oxidation in response to arm cycling exercise in persons with spinal cord injury versus able-bodied

CONTEXT

Persons with spinal cord injury (SCI) present with low fat oxidation that is associated with poor cardiometabolic health. This study compared changes in fat and carbohydrate (CHO) oxidation during moderate intensity continuous exercise in persons with SCI and able-bodied adults (AB).

DESIGN

Repeated measures, within-subjects study.

SETTING

University laboratory in San Diego, CA.

PARTICIPANTS

Nine men and women with SCI (age and time since injury = 32 ± 11 yr and 7 ± 6 yr) and 10 AB adults (age = 25 ± 8 yr).

INTERVENTIONS

To assess peak oxygen uptake (VO2peak) and peak power output (PPO), participants performed progressive arm ergometry to volitional exhaustion. Subsequently, they completed 25 min of continuous exercise at 45%PPO.

OUTCOME MEASURES

Respiratory exchange ratio (RER), fat and CHO oxidation, and blood lactate concentration (BLa) were assessed.

RESULTS

Data showed a similar RER (P = 0.98) during exercise in SCI (0.97 ± 0.04) versus AB (0.97 ± 0.03) reflecting high CHO use and no differences in BLa (3.5 ± 1.1 and 3.0 ± 0.9 vs. mM, P = 0.56) or fat and CHO oxidation between groups (P > 0.05). However, participants with SCI exercised at a higher relative intensity (P < 0.01, 84 ± 7 vs. 75 ± 7%HRpeak) versus AB.

CONCLUSION

Data confirm high reliance on CHO during arm ergometry in persons with SCI. To better compare substrate utilization to AB adults, we recommend that exercise be prescribed according to peak heart rate due to differences in cardiorespiratory fitness between groups.

Cardiometabolic risk profiling during spinal cord injury rehabilitation: A longitudinal analysis from Swiss Spinal Cord Injury cohort (SwiSCI)

BACKGROUND

Early screening is important in individuals with spinal cord injury (SCI) as they were deemed high-risk for cardiometabolic diseases. Few studies explored changes in cardiometabolic risk profile in the early phase of the injury. Thus, it remains unclear how early the cardiometabolic status deteriorates after injury.

OBJECTIVE

We determined the longitudinal changes in the cardiometabolic risk profile and examined the association between injury characteristics and cardiometabolic status in subacute SCI.

SETTING

Multicenter Swiss Spinal Cord Injury Cohort.

PARTICIPANTS

Adults with traumatic SCI without history of cardiovascular disease or type 2 diabetes.

MAIN OUTCOME MEASURES

Blood pressure (BP), lipid profile, fasting glucose, waist circumference (WC), weight, body mass index (BMI) and Framingham risk score (FRS) were compared across time and according to the injury characteristics.

RESULTS

We analyzed the data of 258 individuals with traumatic SCI (110 tetraplegia and 148 paraplegia, 122 motor complete and 136 incomplete). The median age was 50 years (IQR 32-60), with 76.36% (n=197) of the population being male. The median rehabilitation duration was 5.5 months (IQR 3.2-7.1). At admission to rehabilitation, fully-adjusted linear regression models showed higher baseline weight (β 0.06, 95% CI 0.005, 0.11), systolic BP (β 0.05, 95% CI 0.008, 0.09), diastolic BP (β 0.05 95% CI 0.004, 0.10), and triglycerides (β 0.27 95% CI 0.13, 0.42) in paraplegia than tetraplegia. Systolic BP, diastolic BP, HDL-C were higher in incomplete than complete injury. In our main analysis, we observed an increase in cholesterol and HDL-C and lipid ratio when comparing the beginning and end of rehabilitation. Individuals with paraplegia had a higher increase in BMI than tetraplegia, while no differences in other cardiometabolic risk factors were detected when comparing motor incomplete and complete injury. Trajectories of each participant showed that the majority of individuals with SCI decreased FRS score at follow-up compared to baseline and no significant changes in prevalence of cardiometabolic syndrome were observed. At discharge, one-third of study participants were classified as moderate to high risk of CVD, 64% were overweight, and 39.45% had cardiometabolic syndrome.

CONCLUSION

We observed a modest improvement in lipid profile and FRS during the first inpatient rehabilitation hospitalization. Injury characteristics, such as level and completeness, were not associated with changes in cardiometabolic risk factors in the subacute phase of the injury. Despite this, a significant proportion of study participants remained at risk of cardiometabolic disease at discharge, suggesting that early cardiometabolic preventive strategies may be initiated as early as during the first inpatient rehabilitation hospitalization. This article is protected by copyright. All rights reserved.

An observational study on body mass index during rehabilitation and follow-up in people with spinal cord injury in Denmark

STUDY DESIGN

Observational study OBJECTIVE: To describe body mass index (BMI) during rehabilitation in people with a newly sustained spinal cord injury (SCI).

SETTING

Inpatient SCI rehabilitation in Denmark.

PARTICIPANTS

Inpatients, >18 years, having sustained a SCI within the last 12 months at admission to primary rehabilitation, inclusive of various SCI etiology, neurological level, completeness of the lesion or mobility status.

METHODS

Measures of BMI were obtained at admission and discharge as part of standard care. At one SCI center measures of BMI were sampled at follow up 9.5 months after discharge as well. BMI was described by mean and standard deviation (SD). Paired t-test was used to test difference in BMI between admission and discharge. Repeated measures Analysis of Variance (ANOVA) was used for analyzing BMI deriving from three time points.

RESULTS

Overall BMI was stable with no change (25.4 kg/m² at admission and 25.6 kg/m² at discharge) during rehabilitation at the two national centers. In participants with an American Spinal Injury Association (ASIA) Impairment Scale (AIS) D classification, BMI was higher during rehabilitation compared to the other groups and increased significantly (p = 0.008) from discharge to follow up.

CONCLUSIONS

Overall BMI was stable but higher than recommended in people with SCI undergoing rehabilitation at the two national centers in Denmark. Participants with an AIS D SCI were obese according to SCI adjusted BMI and the World Health Organization (WHO) recommendations during rehabilitation and at follow up.

Peripheral Immune Dysfunction: A Problem of Central Importance after Spinal Cord Injury

Simple Summary

Spinal cord injury can result in an increased vulnerability to infections, but until recently the biological mechanisms behind this observation were not well defined. Immunosuppression and concurrent sustained peripheral inflammation after spinal cord injury have been observed in preclinical and clinical studies, now termed spinal cord injury-induced immune depression syndrome. Recent research indicates a key instigator of this immune dysfunction is altered sympathetic input to lymphoid organs, such as the spleen, resulting in a wide array of secondary effects that can, in turn, exacerbate immune pathology. In this review, we discuss what we know about immune dysfunction after spinal cord injury, why it occurs, and how we might treat it.

Abstract

Individuals with spinal cord injuries (SCI) exhibit increased susceptibility to infection, with pneumonia consistently ranking as a leading cause of death. Despite this statistic, chronic inflammation and concurrent immune suppression have only recently begun to be explored mechanistically. Investigators have now identified numerous changes that occur in the peripheral immune system post-SCI, including splenic atrophy, reduced circulating lymphocytes, and impaired lymphocyte function. These effects stem from maladaptive changes in the spinal cord after injury, including plasticity within the spinal sympathetic reflex circuit that results in exaggerated sympathetic output in response to peripheral stimulation below injury level. Such pathological activity is particularly evident after a severe high-level injury above thoracic spinal cord segment 6, greatly increasing the risk of the development of sympathetic hyperreflexia and subsequent disrupted regulation of lymphoid organs. Encouragingly, studies have presented evidence for promising therapies, such as modulation of neuroimmune activity, to improve regulation of peripheral immune function. In this review, we summarize recent publications examining (1) how various immune functions and populations are affected, (2) mechanisms behind SCI-induced immune dysfunction, and (3) potential interventions to improve SCI individuals’ immunological function to strengthen resistance to potentially deadly infections.

Virtual Strategies for the Broad Delivery of High Intensity Exercise in Persons With Spinal Cord Injury: Ongoing Studies and Considerations for Implementation

Spinal cord injury (SCI) results in a multitude of metabolic co-morbidities that can be managed by exercise. As in the non-injured population, manipulation of exercise intensity likely allows for fruitful optimization of exercise interventions targeting metabolic health in persons with SCI. In this population, interventions employing circuit resistance training (CRT) exhibit significant improvements in outcomes including cardiorespiratory fitness, muscular strength, and blood lipids, and recent exploration of high intensity interval training (HIIT) suggests the potential of this strategy to enhance health and fitness. However, the neurological consequences of SCI result in safety considerations and constrain exercise approaches, resulting in the need for specialized exercise practitioners. Furthermore, transportation challenges, inaccessibility of exercise facilities, and other barriers limit the translation of high intensity "real world" exercise strategies. Delivering exercise via online ("virtual") platforms overcomes certain access barriers while allowing for broad distribution of high intensity exercise despite the limited number of population-specific exercise specialists. In this review, we initially discuss the need for "real world" high intensity exercise strategies in persons with SCI. We then consider the advantages and logistics of using virtual platforms to broadly deliver high intensity exercise in this population. Safety and risk mitigation are considered first followed by identifying strategies and technologies for delivery and monitoring of virtual high intensity exercise. Throughout the review, we discuss approaches from previous and ongoing trials and conclude by giving considerations for future efforts in this area.

Strategies used by providers to support individuals with spinal cord injury in weight management: a qualitative study of provider perspectives

STUDY DESIGN

This is a descriptive qualitative study.

OBJECTIVES

To explore recommended strategies employed by healthcare providers to support individuals with SCI in weight management.

SETTING

Fourteen veteran administration hospitals in the United States and the Shirley Ryan AbilityLab (SRALab) SCI Model Systems in Illinois.

METHODS

Semi-structured interviews were conducted with interprofessional SCI providers involved in weight management with individuals living with SCI. Thematic analysis methods were used.

RESULTS

A total of 25 interprofessional providers were interviewed. Providing clinical expertise to assist in weight management included (1) checking progress or status of weight over time, (2) monitoring and tracking other health-related indicators, (3) stressing weight-related health risks, (4) providing education, (5) encouraging healthy behaviors, and (6) identifying and accessing resources. Fostering provider-patient relationships included (1) establishing and maintaining rapport and (2) tailoring/individualizing weight management treatment. Coordinating a team approach included (1) involving a dietitian or nutritionist, (2) communicating the same message, and (3) involving the informal caregiver/family.

CONCLUSION

Weight management strategies should incorporate patient preferences and goals, informed through provider expert and personalized clinical advice, and supported within the context of interprofessional team collaboration that includes caregivers and family.

Neither Postabsorptive Resting Nor Postprandial Fat Oxidation Are Related to Peak Fat Oxidation in Men With Chronic Paraplegia

The peak rate of fat oxidation (PFO) achieved during a graded exercise test is an important indicator of metabolic health. In healthy individuals, there is a significant positive association between PFO and total daily fat oxidation (FO). However, conditions resulting in metabolic dysfunction may cause a disconnect between PFO and non-exercise FO. Ten adult men with chronic thoracic spinal cord injury (SCI) completed a graded arm exercise test. On a separate day following an overnight fast (≥ 10 h), they rested for 60 min before ingesting a liquid mixed meal (600 kcal; 35% fat, 50% carbohydrate, 15% protein). Expired gases were collected and indirect calorimetry data used to determine FO at rest, before and after feeding, and during the graded exercise test. Participants had “good” cardiorespiratory fitness (VO_2peak: 19.2 ± 5.2 ml/kg/min) based on normative reference values for SCI. There was a strong positive correlation between PFO (0.30 ± 0.08 g/min) and VO_2peak (r = 0.86, p = 0.002). Additionally, postabsorptive FO at rest was significantly and positively correlated with postprandial peak FO (r = 0.77, p = 0.01). However, PFO was not significantly associated with postabsorptive FO at rest (0.08 ± 0.02 g/min; p = 0.97), postprandial peak FO (0.10 ± 0.03 g/min; p = 0.43), or incremental area under the curve postprandial FO (p = 0.22). It may be advantageous to assess both postabsorptive FO at rest and PFO in those with SCI to gain a more complete picture of their metabolic flexibility and long-term metabolic health.

The Role of Lipids, Lipid Metabolism and Ectopic Lipid Accumulation in Axon Growth, Regeneration and Repair after CNS Injury and Disease

Axons in the adult mammalian nervous system can extend over formidable distances, up to one meter or more in humans. During development, axonal and dendritic growth requires continuous addition of new membrane. Of the three major kinds of membrane lipids, phospholipids are the most abundant in all cell membranes, including neurons. Not only immature axons, but also severed axons in the adult require large amounts of lipids for axon regeneration to occur. Lipids also serve as energy storage, signaling molecules and they contribute to tissue physiology, as demonstrated by a variety of metabolic disorders in which harmful amounts of lipids accumulate in various tissues through the body. Detrimental changes in lipid metabolism and excess accumulation of lipids contribute to a lack of axon regeneration, poor neurological outcome and complications after a variety of central nervous system (CNS) trauma including brain and spinal cord injury. Recent evidence indicates that rewiring lipid metabolism can be manipulated for therapeutic gain, as it favors conditions for axon regeneration and CNS repair. Here, we review the role of lipids, lipid metabolism and ectopic lipid accumulation in axon growth, regeneration and CNS repair. In addition, we outline molecular and pharmacological strategies to fine-tune lipid composition and energy metabolism in neurons and non-neuronal cells that can be exploited to improve neurological recovery after CNS trauma and disease.

Dietetics After Spinal Cord Injury: Current Evidence and Future Perspectives

Following spinal cord injury (SCI), individuals are at high risk for obesity and several chronic cardiometabolic disorders due to a deterioration in body composition, hypometabolic rate, and endometabolic dysregulation. Countermeasures to the consequences of an SCI include adopting a healthy diet that provides adequate nutrition to maintain good body habitus and cardiometabolic health. A proper diet for individuals with SCI should distribute carbohydrates, protein, and fat to optimize a lower energy intake requirement and should stress foods with low caloric yet high nutrient density. The purpose of this article is to present available evidence on how nutritional status after SCI should advance future research to further develop SCI-specific guidelines for total energy intake, as it relates to percent carbohydrates, protein, fat, and all vitamins and minerals, that take into consideration the adaptations after SCI.

Substrate metabolism during recovery from circuit resistance exercise in persons with spinal cord injury

INTRODUCTION

Whole body energy expenditure and lipid oxidation (Lox) are upregulated during and after exercise. Persons with spinal cord injury (SCI) generally have a blunted ability to utilize fat during exercise, but it is unknown if their substrate partitioning is affected during recovery from exercise.

PURPOSE

To determine the effect of a single session of upper body circuit resistance exercise (CRE) on energy expenditure and Lox during exercise recovery in persons with and without SCI.

METHODS

Twenty four persons (3 groups; 7 male and 1 female per group) without paralysis (neurologically intact; N) or with chronic (≥ 1 yr) paraplegia (P) or tetraplegia (T) participated. Energy expenditure and substrate partitioning were assessed via indirect calorimetry before, during, and three times after (up to 120 min after) a single session of CRE, or time-matched seated control (CON).

RESULTS

During CRE, all groups experienced a similar relative increase in oxygen consumption (49 ± 13, 55 ± 11, and 48 ± 15% VO_2peak for N, P, and T, respectively). The Post_0-120 energy expenditure was greater following CRE vs. CON (P < 0.01) and independent of injury characteristics (10.6, 22.6, and 14.3% higher than CON for N, P, and T; P = 0.21). The absolute increase in Lox above CON during recovery was similar for N, P, and T (5.74 ± 2.81, 6.62 ± 3.10, and 4.50 ± 3.91 g, respectively; P = 0.45).

CONCLUSIONS

Energy expenditure and lipid utilization was increased similarly following circuit exercise in persons without and with spinal cord injury in a manner independent of level of injury.

Effect of Paraplegia on the Time Course of Exogenous Fatty Acid Incorporation Into the Plasma Triacylglycerol Pool in the Postprandial State

Spinal cord injury (SCI) results in disordered fat metabolism. Autonomic decentralization might contribute to dyslipidemia in SCI, in part by influencing the uptake of dietary fats through the gut-lymph complex. However, the neurogenic contributions to dietary fat metabolism are unknown in this population. We present a subset of results from an ongoing registered clinical trial (NCT03691532) related to dietary fat absorption. We fed a standardized (20 kcal⋅kgFFM^–1) liquid meal tolerance test (50% carb, 35% fat, and 15% protein) that contained stable isotope lipid tracer (5 mg⋅kgFFM^–1 [U-¹³C]palmitate) to persons with and without motor complete thoracic SCI. Blood samples were collected at six postprandial time points over 400 min. Changes in dietary fatty acid incorporated into the triacylglycerol (TAG) pool (“exogenous TAG”) were used as a marker of dietary fat absorption. This biomarker showed that those with paraplegia had a lower amplitude than non-injured participants at Post₂₄₀ (52.4 ± 11.0 vs. 77.5 ± 16.0 μM), although this failed to reach statistical significance (p = 0.328). However, group differences in the time course of absorption were notable. The injury level was also strongly correlated with time-to-peak exogenous TAG concentration (r = −0.806, p = 0.012), with higher injuries resulting in a slower rise in exogenous TAG. This time course documenting exogenous TAG change is the first to show a potential neurogenic alteration in SCI dietary fat absorption.

Neurogenic Obesity and Skeletal Pathology in Spinal Cord Injury

Spinal cord injury (SCI) results in dramatic changes in body composition, with lean mass decreasing and fat mass increasing in specific regions that have important cardiometabolic implications. Accordingly, the recent Consortium for Spinal Cord Medicine (CSCM) released clinical practice guidelines for cardiometabolic disease (CMD) in SCI recommending the use of compartmental modeling of body composition to determine obesity in adults with SCI. This recommendation is guided by the fact that fat depots impact metabolic health differently, and in SCI adiposity increases around the viscera, skeletal muscle, and bone marrow. The contribution of skeletal muscle atrophy to decreased lean mass is self-evident, but the profound loss of bone is often less appreciated due to methodological considerations. General-population protocols for dual-energy x-ray absorptiometry (DXA) disregard assessment of the sites of greatest bone loss in SCI, but the International Society for Clinical Densitometry (ISCD) recently released an official position on the use of DXA to diagnose skeletal pathology in SCI. In this review, we discuss the recent guidelines regarding the evaluation and monitoring of obesity and bone loss in SCI. Then we consider the possible interactions of obesity and bone, including emerging evidence suggesting the possible influence of metabolic, autonomic, and endocrine function on bone health in SCI.

Effect of Exercise on Cardiovascular Function Following Spinal Cord Injury: A REVIEW

Spinal cord injury (SCI) is associated with a reduced level of physical activity, deterioration of patient body composition, metabolic profile, quality of life, and psychological functioning. As a result, risk of cardiovascular disease (CVD) increases and CVD-related death occurs at an earlier age than in individuals without SCI. Regular participation in exercise has been shown to exert beneficial effects also in patients with SCI. In this review, we analyze and discuss the effects of regular exercise training in SCI on cardiovascular function, autonomic function of the cardiovascular system, arterial stiffness, metabolism, inflammation, and gene expression.

Physiological responses to moderate intensity continuous and high-intensity interval exercise in persons with paraplegia

STUDY DESIGN

Randomized crossover.

OBJECTIVES

To test differences in the duration and magnitude of physiological response to isocaloric moderate intensity continuous (MICE) and high-intensity interval exercise (HIIE) sessions in persons with spinal cord injury (SCI).

SETTING

Academic medical center in Miami, FL, USA.

METHODS

Ten adult men (mean ± s.d.; 39 ± 10 year old) with chronic (13.2 ± 8.8 year) paraplegia (T2-T10) completed a graded exercise test. Then, in a randomized order, participants completed MICE and HIIE for a cost of 120 kcal. MICE was performed at 24.6% PO_peak. During HIIE, exercise was completed in 2 min work and recovery phases at 70%:10% PO_peak.

RESULTS

MICE and HIIE were isocaloric (115.9 ± 21.8 and 116.6 ± 35.0 kcal, respectively; p = 0.903), but differed in duration (39.8 ± 4.6 vs 32.2 ± 6.2 min; p < 0.001) and average respiratory exchange ratio (RER; 0.90 ± 0.08 vs 1.01 ± 0.07; p = 0.002). During MICE, a workrate of 24.6 ± 6.7% PO_peak elicited a V̇O₂ of 53.1 ± 6.5% V̇O_2peak (10.1 ± 2.2 ml kg^-1 min^-1). During HIIE, a workrate at 70% PO_peak elicited 88.3 ± 6.7% V̇O_2peak (16.9 ± 4.2 ml kg^-1 min^-1), and 29.4 ± 7.7% of the session was spent at or above 80% V̇O_2peak. During HIIE working phase, RER declined from the first to last interval (1.08 ± 0.07 vs 0.98 ± 0.09; p < 0.001), reflecting an initially high but declining glycolytic rate.

CONCLUSIONS

Compared with MICE, HIIE imposed a greater physiological stimulus while requiring less time to achieve a target caloric expenditure. Thus, exercise intensity might be an important consideration in the tailoring of exercise prescription to address the cardiometabolic comorbidities of SCI.

Classification of obesity, cardiometabolic risk, and metabolic syndrome in adults with spinal cord injury

Objective: To describe and compare (1) classification of obesity using clinical proxies of body composition that are easily accessible in the outpatient clinic setting, (2) cardiometabolic risk using existing screening tools and staging systems, and (3) the presence of metabolic syndrome (MetS) using four commonly-used definitions in adults with spinal cord injury (SCI). Design: Retrospective chart review Setting: Outpatient Veterans Affairs (VA) SCI Annual Evaluation Clinic Participants: Patients who attended an annual evaluation appointment with demographic, anthropometric, and biochemical data documented in their medical records as part of routine medical care. Outcome measures: Obesity classification (body mass index, waist circumference, ideal body weight percentage), cardiometabolic risk scores (Framingham Risk Score, Cardiometabolic Disease Staging System, Edmonton Obesity Staging System), and MetS classification (using four commonly-used definitions) were described and compared. Results: Of the 155 veterans included in this analysis, 93% were considered "at risk" by at least one of the measurements studied. However, there was considerable variation between the different screening tools. The κ-agreement between various definitions of MetS ranged from fair to moderate. Conclusion: Screening tools that were developed for the non-SCI population produced variable assessments of risk when applied to veterans with SCI. Due to the fair to moderate inter-rater agreement between MetS definitions, it is unknown which definition is superior to identify MetS in the SCI population. An SCI-specific screening tool is needed to accurately classify obesity, cardiometabolic risk, and MetS in order to provide timely education and intervention.

A Provider's Guide to Vascular Disease, Dyslipidemia, and Glycemic Dysregulation in Chronic Spinal Cord Injury

Individuals with chronic spinal cord injury (SCI) are predisposed to accelerated atherogenesis, dyslipidemia, and glycemic dysregulation, although not enough is known about the etiologies or clinical consequences of these secondary effects of paralysis. While guidelines for the detection and treatment of cardiometabolic disease in SCI have recently been published, there has been a historical paucity of data-driven approaches to these conditions. This article will describe what is and not known about the cardiovascular disease and glycemic dysregulation that frequently attend SCI. It will conclude with a review of both guideline-driven and informal recommendations addressing the clinical care of people living with SCI.

Measurement of Visceral Adipose Tissue in Persons With Spinal Cord Injury by Magnetic Resonance Imaging and Dual X-Ray Absorptiometry: Generation and Application of a Predictive Equation

PURPOSE

Dual energy X-ray absorptiometry (DXA) and magnetic resonance imaging (MRI) permits quantification of visceral adipose tissue (VAT). However, DXA has not been validated against MRI in persons with chronic spinal cord injury (SCI). A predictive equation was generated from the measurement of VAT by MRI, a "gold" standard to quantitate VAT, compared to that of DXA, a method with several practical advantages.

METHOD

DXA and MRI scans were performed in 27 participants with SCI. MRI multiaxial images were captured for VAT analysis. DXA-VAT was quantified at the android region (DXA-VAT_ANDROID-VOL) using enCore software. Android regions of DXA and MRI were matched using android height. Volumes of multiaxial MRI-VAT and subcutaneous adipose tissue (SAT) were quantified for the android region (MRI-VAT_ANDROID-VOL, MRI-SAT_ANDROID-VOL) and total trunk (MRI-VAT_ANDROID-VOL). Linear regression analysis was used to establish the proposed predication equations. The prediction equations were then applied to an independent sample that consisted of 98 participants with SCI. Bland-Altman analysis was used to determine the limits of agreement.

RESULTS

DXA-VAT_ANDROID-VOL predicted 92% of the variance in MRI-VAT_ANDROID-VOL (SEE = 252.5, p < 0.0005) and 85% of the variance in MRI-VAT_TRUNK-VOL (SEE = 1526.9, p < 0.0005). DXA-SAT_ANDROID-VOL predicted 81.5% of the variance in MRI-SAT_ANDROID-VOL (SEE = 458.2, p < 0.0005). Bland-Altman analysis revealed a high level of agreement between MRI-VAT_ANDROID-VOL and DXA-VAT_ANDROID-VOL (mean bias = 58.45 cm³). A predicted mean DXA-VAT_ANDROID-VOL of 995.2 cm³ was estimated as the population-specific cut-off point for high levels of VAT.

CONCLUSION

DXA-VAT_ANDROID-VOL may accurately predict MRI-VAT_ANDROID-VOL in persons with SCI. The ability of DXA to detect VAT changes in longitudinal studies in persons with SCI should be performed.

Health promotion and cardiovascular risk reduction in people with spinal cord injury: physical activity, healthy diet and maintenance after discharge- protocol for a prospective national cohort study and a preintervention- postintervention study

INTRODUCTION

Spinal cord injury (SCI) predisposes those who suffer from it to physical inactivity and weight gain; consequently, death due to cardiovascular diseases is more frequent among people with SCI than in the general population. The literature documents a consensus about an interdisciplinary multimodal approach for the prevention and treatment of cardiovascular risk factors including overweight and obesity in people with SCI, focusing on diet, physical activity (PA) and behavioural interventions. This study will investigate implementation of recommendations from a recent clinical practice guideline for identification and management of cardiometabolic risk after SCI through multimodal patient education in a subacute clinical setting.

METHODS AND ANALYSIS

All patients who are aged 18 years or older with an SCI within the previous 12 months and admitted to highly specialised rehabilitation are included, regardless of SCI aetiology or neurological level. A primary study designed as a controlled, pragmatic, preintervention- postintervention study with 6-month follow-up evaluates the effect of the clinical intervention; a prospective national cohort study on body mass index (BMI) serves as a historical control. The intervention consists of a standardised approach to patient education about cardiovascular risk factors, PA and a healthy diet that begins at the outset of primary SCI rehabilitation and is integrated into existing settings and workflows. Outcome measures are collected at admission, discharge and 6 months after discharge and include peak oxygen uptake (VO2peak) (primary outcome), BMI, body composition, metabolic profile, neurological status, level of functioning, depression, quality of life, objective PA (accelerometry), self-reported PA, self-assessed PA ability, shared decision making, and dietary habits. Test-retest reliability of four VO2peak test protocols are investigated, as is test-retest reliability of a multisensor accelerometer in a rehabilitation setting.

ETHICS AND DISSEMINATION

The project is approved by the Committees on Health Research Ethics in the Capital Region of Denmark on 10 July 2018 (Journal-nr.: H-18018325). The principal investigator obtains informed consent from all participants. The interventions in the project are closely related to existing rehabilitation care, and the risk of pain and discomfort is considered modest. Any unintended events related to the elements of the intervention are reported, according to existing regional procedures. Data are stored in a secure web-based database (Redcap). The primary study and prospective cohort study are registered at Clinicaltrials.gov. Positive and negative results will be submitted to relevant scientific journals related to SCI for publication. Important protocol modifications are reported to the Committees on Health Research Ethics in the Capital Region of Denmark.

TRIAL REGISTRATION NUMBERS

NCT03689023 and NCT03369080.

Addressing cardiometabolic risk in adults with spinal cord injury: acting now despite knowledge gaps

This perspective advocates for the adoption of recently published clinical practice guidelines on identifying and managing cardiometabolic risk after spinal cord injury (SCI). It makes the case for acting now, with the knowledge that we currently have, while continuing to address knowledge gaps with high-quality research studies in this area. Cardiovascular disease is a leading cause of death in people with SCI. Cardiometabolic disease (CMD) and risks are more likely to be overlooked after SCI. Unique SCI-related considerations impact both assessment and management of cardiometabolic risk. Risk factors and components of CMD including obesity, impaired glucose tolerance/insulin resistance, dyslipidemia, and hypertension should be evaluated and managed to optimize the cardiometabolic health of this population. While it would be optimal to base all care on high-quality evidence-based research, its absence should not be an excuse for inaction. Applying what is currently known and filling the research gaps with empirical recommendations based on clinical rationale and expert consensus is both appropriate and necessary till more definitive SCI-specific evidence becomes available.

Prevalence of metabolic syndrome in veterans with spinal cord injury

CONTEXT/OBJECTIVE

Recent literature would suggest the prevalence of metabolic syndrome in persons with spinal cord injury (SCI) is higher than that of the general population, although no large cohorts have yet been reported. Part of the controversy relates to the differing definitions provided for metabolic syndrome and the characterization of obesity in persons with SCI.

DESIGN/PARTICIPANTS

The current retrospective investigation represents a cross-sectional cohort of 473 veterans with SCI from a single center in the mid-Atlantic region of the United States for whom modified International Diabetes Federation (IDF) criterion variables for the metabolic syndrome were available in the computerized personal record system (CPRS).

OUTCOME MEASURES

These variables included a surrogate marker of obesity appropriate to SCI (Body Mass Index (BMI) ≥ 22 kg/m2), as well as indicators of diabetes, dyslipidemia and hypertension.

RESULTS

Over 57% of the veterans assessed were determined to have metabolic syndrome by modified IDF criteria, including 76.7% with BMI ≥ 22 kg/m2, 55.1% with or under treatment for hypertension, 49.7% with or previously diagnosed with diabetes mellitus, and 69.7% with or under treatment for high density lipoprotein (HDL) cholesterol under 40 mg/dl.

CONCLUSION

Metabolic syndrome and its constituent components appear to be more prevalent in veterans with SCI than in the general population, suggesting a greater need for identification and treatment interventions in this specialty population.

Establishing a threshold to predict risk of cardiovascular disease from the serum triglyceride and high-density lipoprotein concentrations in persons with spinal cord injury

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

This report identified the serum triglyceride (TG) concentrations in persons with spinal cord injury (SCI) and able-bodied (AB) individuals that the serum high-density lipoprotein cholesterol (HDL-C) equaled 40 mg/dl, a concentration below which is an independent risk factor for coronary artery disease.

METHODS

Retrospective analysis was performed on 578 participants: 223 with SCI at or proximal to the 4th thoracic vertebrae (↑T4), 178 with SCI at or distal to the 5th thoracic vertebrae (↓T5), and 177 AB. Different statistical modeling approaches identified the intersecting serum TG concentration with a serum HDL-C concentration equal to 40 mg/dl. Participants were dichotomized into subgroups by TG concentration exceeding (supra) or falling below (sub) the intersecting value and the TG/HDL-C ratios were compared.

RESULTS

Linear regression analysis revealed that the serum TG concentration that intersects with serum HDL-C concentration at 40 mg/dl was 121 mg/dl in SCI ↑T4 and 137 mg/dl in SCI ↓T5 group. A ROC curve identified the optimal TG concentration as 115 mg/dl in SCI ↑T4 and 137 mg/dl in SCI ↓T5 group with the latter concentration being similar to the AB group (e.g., 137 mg/dl). The TG/HDL-C ratios in the respective ↑T4, ↓T5, and AB supra and subgroups were similar within each group.

CONCLUSIONS

A lower TG concentration appears to be associated with dyslipidemia in persons with SCI than AB individuals. These findings should prompt clinicians to screen for and consider instituting lifestyle or pharmacological interventions at lower TG concentrations to reduce risk of CVD.

Exercise and Health-Related Risks of Physical Deconditioning After Spinal Cord Injury

A sedentary lifestyle occurring soon after spinal cord injury (SCI) may be in contrast to a preinjury history of active physical engagement and is thereafter associated with profound physical deconditioning sustained throughout the lifespan. This physical deconditioning contributes in varying degrees to lifelong medical complications, including accelerated cardiovascular disease, insulin resistance, osteopenia, and visceral obesity. Unlike persons without disability for whom exercise is readily available and easily accomplished, exercise options for persons with SCI are more limited. Depending on the level of injury, the metabolic responses to acute exercise may also be less robust than those accompanying exercise in persons without disability, the training benefits more difficult to achieve, and the risks of ill-considered exercise both greater and potentially irreversible. For exercise to ultimately promote benefit and not impose additional impairment, an understanding of exercise opportunities and risks if exercise is undertaken by those with SCI is important. The following monograph will thus address common medical challenges experienced by persons with SCI and typical modes and benefits of voluntary exercise conditioning.

Acute Myocardial Infarction in Patients with Paraplegia: Characteristics, Management, and Outcomes

BACKGROUND

Cardiovascular disease has become a leading cause of death for patients with paraplegia. Acute myocardial infarction in patients with paraplegia has not been described in the literature. This study investigates clinical features, management strategies, and outcomes of these patients.

METHODS

Acute myocardial infarction in patients with or without paraplegia was identified in the New York State Inpatient Database between 2007 and 2013. Clinical comorbidities, management strategies and their associated outcomes were compared using propensity score-matching analysis.

RESULTS

Among 402,569 patients with acute myocardial infarction, 1400 had a concomitant diagnosis of paraplegia. Compared with those without, patients with paraplegia were younger, more likely to be black, and had a higher prevalence of hypertension, anemia, congestive heart failure, coagulopathy, and depression, but a lower prevalence of diabetes, hyperlipidemia, obesity, chronic lung disease, and renal failure. Patients with paraplegia were more likely to receive medical therapy without a diagnostic cardiac catheterization than those without (83.7% vs 64.5%, P < .001). Nine percent of patients with paraplegia received revascularization, which was significantly lower than that without paraplegia. In terms of the clinical outcome, patients with paraplegia had higher in-hospital mortality than those without (22.4% vs 16.8%, P < .001). Among the patients with paraplegia, the subcohort that received revascularization had lower in-hospital mortality (9.5% vs 22.0%, P < .01), had shorter length of stay (13.0 vs 16.9 days, P =.08), and higher hospital charges ($130,079 vs $92,125, P < .001) than those without revascularization. Furthermore, the paraplegic subcohort underwent coronary artery bypass grafting that was associated with higher in-hospital mortality (21.7% vs 1.7%, P < .001), longer length of stay (24.8 vs 14.2 days, P < .001), and higher hospital charges ($231,323 vs $144,449, P < .01) than subcohort that received percutaneous coronary intervention.

CONCLUSIONS

Acute myocardial infarction patients with concomitant paraplegia had distinct clinical characteristics and comorbidity profiles; were less likely to receive revascularization therapy; and had higher in-hospital mortality. Acute myocardial infarction patient with paraplegia who underwent revascularization were associated with better clinical outcomes, in particular, those who were treated with percutaneous coronary intervention had significantly lower in-hospital mortality than those treated with coronary artery bypass grafting.

Relationship Between Gonadal Function and Cardiometabolic Risk in Young Men With Chronic Spinal Cord Injury

BACKGROUND

We reported previously that young men with chronic spinal cord injury (SCI) have a greater prevalence of testosterone deficiency compared with an age-matched, healthy control population. Young men with SCI also are at increased risk for developing cardiometabolic dysfunction after injury. It is unclear whether testosterone deficiency is associated with heightened cardiometabolic risk in men with SCI.

OBJECTIVE

To investigate associations among levels of testosterone in young men with chronic SCI and surrogate markers of cardiometabolic risk.

DESIGN

Secondary cross-sectional analysis.

SETTING

Rehabilitation research centers in Washington, DC, and Miami, Florida.

PARTICIPANTS

Men (n = 58) aged 18-45 years with chronic (≥1 year), motor complete SCI without comorbidities or use of testosterone therapy.

METHODS

Plasma concentrations of testosterone, lipids, inflammatory markers (C-reactive protein and interleukin-6), percent hemoglobin A1c, glucose, and insulin were measured in a fasting state using standard assays. A 2-hour oral glucose tolerance test and Framingham Risk Score were assessed for each subject. Body composition was assessed by dual X-ray absorptiometry scan.

MAIN OUTCOME MEASUREMENTS

Surrogate markers of cardiometabolic risk among men based on the level of total testosterone (TT; ≤300, 301-500, or >500 ng/dL) and free testosterone (fT; ≤9 or >9 ng/dL). Comparisons were made between men with normal and low TT or fT.

RESULTS

Framingham Risk Score was significantly greater in men with low fT (P < .05). Percent body fat (P < .05) and waist-to-hip ratio (P < .05) but not body mass index (P > .08), were greater in men with low TT or low fT. Men with low TT or low fT had lower high-density lipoprotein cholesterol levels (P < .05) without differences in fasting triglycerides (P > .1) or low-density lipoprotein cholesterol (P > .07). Men with low TT had greater levels of inflammatory markers C-reactive protein (P < .05) and interleukin-6 (P < .05). Men with low TT or low fT had greater fasting glucose (P < .05) and greater insulin resistance (P < .04), without differences in percent hemoglobin A1c (P > .8).

CONCLUSIONS

In young men with chronic SCI who undergo an accelerated aging process postinjury, hypogonadism is associated with an unfavorable cardiometabolic risk profile. Further research is needed to determine whether a causal relationship exists between hypogonadism and heightened cardiometabolic risk in men with SCI and whether routine screening for testosterone deficiency is warranted in this population.

LEVEL OF EVIDENCE

IV.

Cardiovascular disease risk in individuals with chronic spinal cord injury: Prevalence of untreated risk factors and poor adherence to treatment guidelines

BACKGROUND/OBJECTIVE

Cardiovascular disease (CVD) is currently the leading cause of mortality among individuals living with chronic spinal cord injury (SCI). The purpose of this study is to: 1) Describe the prevalence of CVD risk factors including dyslipidemia (DYS), hypertension (HTN) and type II diabetes mellitus (DM) in patients with chronic SCI; 2) Report the frequency of individuals recommended for diagnostic testing, as per current Canadian CVD diagnostic guidelines; and 3) Report the frequency of individuals receiving guideline-derived appropriate therapy for these risk factors.

METHODS

Adults with a chronic, stable SCI (n = 91) were included in this study. Medical histories, current medications, blood serum analyses and blood pressures were collected and compared to current Canadian CVD diagnostic guidelines to assess for DYS, HTN and DM.

RESULTS

Of the 81 participants with blood serum analyses, 10 (14.7%) of 23 (28.4%) individuals meeting diagnostic criteria for DYS were not taking appropriate statin medication and 2 (2.5%) of 7 (8.6%) individuals meeting diagnostic criteria for DM were not taking appropriate DM medication. Of the 91 participants having BP measurements, 13 (14.3%) of 26 (28.6%) individuals meeting diagnostic criteria for HTN were not taking appropriate BP medication.

CONCLUSIONS

In addition to a high prevalence of CVD risk factors among individuals with chronic SCI, there is also evidence of poor adherence to diagnostic and treatment guidelines for DYS, HTN and DM. The study results highlight an important gap between the observed prevalence of disease and the low rates of screening and guideline adherence in the SCI population.

Rehabilitation Interventions to modify endocrine-metabolic disease risk in Individuals with chronic Spinal cord injury living in the Community (RIISC): A systematic review and scoping perspective

CONTEXT

Endocrine-metabolic disease (EMD) risk following spinal cord injury (SCI) is associated with significant multi-morbidity (i.e. fracture, diabetes, heart disease), mortality, and economic burden. It is unclear to what extent rehabilitation interventions can modify EMD risk and improve health status in community-dwelling adults with chronic SCI.

OBJECTIVES

To characterize rehabilitation interventions and summarize evidence on their efficacy/effectiveness to modify precursors to EMD risk in community-dwelling adults with chronic SCI.

METHODS

Systematic searches of MEDLINE PubMed, EMBASE Ovid, CINAHL, CDSR, and PsychInfo were completed. All randomized, quasi-experimental, and prospective controlled trials comparing rehabilitation/therapeutic interventions with control/placebo interventions in adults with chronic SCI were eligible. Two authors independently selected studies and abstracted data. Mean differences of change from baseline were reported for EMD risk outcomes. The GRADE approach was used to rate the quality of evidence.

RESULTS

Of 489 articles identified, 16 articles (11 studies; n=396) were eligible for inclusion. No studies assessed the effects of rehabilitation interventions on incident fragility fractures, heart disease, and/or diabetes. Individual studies reported that exercise and/or nutrition interventions could improve anthropometric indices, body composition/adiposity, and biomarkers. However, there were also reports of non-statistically significant between-group differences.

CONCLUSIONS

There was very low-quality evidence that rehabilitation interventions can improve precursors to EMD risk in community-dwelling adults with chronic SCI. The small number of studies, imprecise estimates, and inconsistency across studies limited our ability to make conclusions. A high-quality longitudinal intervention trial is needed to inform community-based rehabilitation strategies for EMD risk after chronic SCI.

The analysis of serum lipid levels in patients with spinal cord injury

STUDY DESIGN

Retrospective study.

OBJECTIVES

The purposes of this investigation were to evaluate the serum lipid profile among a broad sample of patients with spinal cord injury (SCI), examining the impact of disease duration, lesion level, lesion grade and functional activity level on serum lipid levels of patients with SCI.

SETTING

Ankara Physical Medicine and Rehabilitation Training and Research Hospital, Turkey.

METHODS

Serum lipid profiles of 269 participants with SCI were analyzed and correlated to disease duration, lesion level, lesion grade and ambulation status.

RESULTS

Total cholesterol (TC) was higher than normal in 21.2%, low density lipoprotein cholesterol in 24.4%, and triglycerides levels in 31% of the patients. The high density lipoprotein cholesterol (HDL-c) level was found to be lower than 40 mg/dl in 79.5% of the patients, TC/HDL-c ratio was 4.5 and above in 65.7% of the patients in our study. TC/HDL-c ratio was significantly higher in patients with SCI with a disease duration of 0-12 months than the group with a longer disease duration (P = 0.009). TC/HDL-c ratio was significantly higher in patients who could not be community ambulated than the patients who were community ambulated (P = 0.005). HDL-c levels in patients with motor complete SCI were significantly lower than patients with motor incomplete SCI (P = 0.028).

CONCLUSION

Dyslipidemia is observed in a large number of patients with SCI. The risk of dyslipidemia was seen to have increased in motor complete SCI patients, in patients who can not be community ambulated and whose disease duration is between 0 to 12 months.

Longitudinal changes in body composition and metabolic profile between exercise clinical trials in men with chronic spinal cord injury

STUDY DESIGN

Longitudinal design.

OBJECTIVES

The study was undertaken to determine the effects of cessation of exercise interventions on body composition and metabolic profiles in men with chronic SCI.

SETTINGS

Clinical trials within a Medical Center.

METHODS

Eleven men with motor complete SCI were followed on average over a period of 2.5 years. Six men were involved in two different exercise interventions (functional electrical stimulation cycling versus arm cycling ergometer), 5 days/week for 16 weeks (exercise group), and five men served as a control (control group). Anthropometrics and dual energy X-ray absorptiometry (DXA) were captured to measure changes in lean mass (LM), fat mass (FM), percentage FM before, immediately after exercise, and after a period of 2.5 years. Basal metabolic rate (BMR) and lipid panel were also measured.

RESULTS

Thigh circumference increased by 8.5% following exercise (P = 0.042) and remained 6.4% greater than baseline measurements (P = 0.012). Leg LM increased by 9% following the exercise intervention (P = 0.03) and decreased by 16% in the follow-up visit (P = 0.02). Percentage trunk and total body FM increased by 4.5% (P = 0.008) and 3.5% (P = 0.019) in the follow-up visit, respectively, and whole body LM increased by 8.4% and decreased back by 5.4% following a 2.5 year-period. BMR significantly decreased by 15.5% following the exercise (P = 0.029) interventions.

CONCLUSION

Exercise training is accompanied with positive changes in body composition as well as compensatory decrease in BMR, that regressed back following 2.5 years of exercise cessation. Participation in an exercise trial is unlikely to confound the measurements of a follow-up trial.

Vitamin D and spinal cord injury: should we care?

STUDY DESIGN

Narrative review.

OBJECTIVES

This review provides an overview of the etiological factors and consequences of vitamin D insufficiency in relation to spinal cord injury (SCI) as well as important considerations for vitamin D supplementation.

SETTING

Montreal, Canada.

METHODS

Literature search.

RESULTS

Vitamin D insufficiency is common in SCI individuals owing to the presence of many contributing factors including limited sun exposure and intake, use of medication and endocrine perturbations. Although there are several biological plausible mechanisms by which vitamin D may act upon musculoskeletal and cardiometabolic health, the impact of vitamin D insufficiency on such systems remains ill defined in SCI. In the absence of guidelines for the management of vitamin D insufficiency in this high-risk population and in an attempt to provide clinical guidance, considerations for vitamin D supplementation such as the type of vitamin D, dosing regimens and toxicity are discussed and tentative recommendations suggested with particular reference to issues faced by SCI patients.

CONCLUSION

Although high rates of vitamin D insufficiency are encountered in SCI individuals, its consequences and the amount of vitamin D required to prevent insufficiency are still unknown, indicating a need for more intervention studies with well-defined outcome measures. Routine screening and monitoring of vitamin D as well as treatment of suboptimal status should be instituted in both acute and chronic setting. The close interactions between vitamin D and related bone minerals should be kept in mind when supplementing SCI individuals, and practices should be individualized with clinical conditions.

Coronary artery disease and hypertension in a non-selected spinal cord injury patient population

STUDY DESIGN

Retrospective observational comparative study.

OBJECTIVES

The objectives of this study were to assess the atherosclerosis diseases and risk factors prevalence after spinal cored injury (SCI).

SETTING

Loewenstein Rehabilitation Hospital, Israel.

METHODS

Data of 154 traumatic and non-traumatic SCI patients were retrospectively collected. Coronary artery disease (CAD), myocardial infarction (MI), hypertension (HT) and risk factors for atherosclerotic diseases were examined after SCI for prevalence and effects, and compared with published corresponding data of the general population.

RESULTS

CAD, MI and HT were found in 11.7, 6.7 and 29.2% of 120 patients, aged 53.4±11.1 years, 83.3% males, who survived until the end of the follow-up. Corresponding values for the general population, adjusted for age, gender and years of education, are 8.5, 6.6 and 24.9% in Israel, and 10.2% for CAD and 40.3% for HT, in US. Body mass index>30 increased the odds of acquiring CAD (P=0.016). Hypercholesterolemia and older age at injury increased the hazard for HT (P=0.044; P=0.019, respectively). A steady partner decreased the risk of CAD (P=0.029). HT was more prevalent at T₄-T₆ than above T₄ (52 vs 23.3%, P=0.02). Patients with SCI below T₆ had a higher rate of diabetes mellitus, hypercholesterolemia, and past smoking, and fewer years of education than those with SCI above T₇ (P=0.016; P=0.032; P=0.034; P=0.014, respectively).

CONCLUSION

The prevalence of CAD, HT and some of their risk factors after SCI is generally, but not consistently and not statistically significant, slightly higher than in the corresponding general population. The challenge is to reduce the prevalence of atherosclerotic morbidity after SCI below that in the general population.

Does Upper Extremity Training Influence Body Composition after Spinal Cord Injury?

Spinal cord injury (SCI) leads to serious body composition adaptations characterized by increasing whole body fat mass and decreased soft tissue lean mass (LM). These adaptations in body composition may lead to several cardio-metabolic disorders that reduce the quality of life, increase patients' and caregivers' burden and eventually leads to mortality. Exercise, an appropriate dietary regimen, and an active lifestyle may alleviate several of the negative effects on body composition after a SCI. Today however, there is no established consensus on the recommended dose, frequency or type of exercise to ameliorate several of the body composition sequelae after an acute SCI. Resistance training has been previously recommended as an effective strategy to restore soft tissue LM and decrease fat mass (FM). The strategy can be simply implemented as a routine home-based training program using free weights or resistance bands after a SCI. Additionally, upper extremity (UE) circuit resistance training has been previously used to improve cardiovascular and metabolic parameters after a SCI; however compared to the vast knowledge regarding the able-bodied (AB) population, the effects of UE circuit resistance training on body composition after a SCI is not well established. In summary, the available evidence does not support the rationale that UE circuit resistance training can lead to positive adaptations in body composition after a SCI. Further studies are suggested to examine the effects of UE circuit resistance training on body composition.

Lipoprotein heterogeneity in persons with Spinal Cord Injury: a model of prolonged sitting and restricted physical activity

BACKGROUND

Persons with spinal cord injury (SCI) often have low levels of physical activity, which predispose to increased adiposity and decreased high density lipoprotein cholesterol (HDL-C) concentrations, and, generally, normal low density lipoprotein cholesterol (LDL-C) concentrations. In spite of the mixed lipoprotein profile, the SCI population has been reported to have an elevated risk of cardiovascular-related morbidity and mortality. Nuclear magnetic resonance spectroscopy may permit a more precise quantification of lipoprotein particle (P) species, enabling a more accurate inference of risk for cardiovascular disease (CVD) in the SCI population.

METHODS

Fasting blood samples were obtained on 83 persons with chronic SCI and 62 able-bodied (AB) subjects. Fasting plasma insulin (FPI), triglycerides (TG), and P number and size of VLDL (very low density lipoprotein), LDL, and HDL subclasses were determined. AB and SCI subjects were stratified based on HDL-C (i.e., Low <40 and Normal ≥ 40 mg/dl): AB-Normal (n = 48), AB-Low (n = 14), SCI-Normal (n = 49), and SCI-Low (n = 34). Factorial analyses of variance were performed to identify group differences in lipoprotein measurements. Pearson correlations were performed between the number of P by lipoprotein subclass, size, FPI, and TG.

RESULTS

The SCI-Normal group was not significantly different from the AB-Normal group for body composition, FPI, TG or LP-IR and had negligible differences in the lipoprotein P profile, except for fewer number and smaller size of HDL-P. The SCI-Low group had a similar lipoprotein profile to that of the AB-Low group, but with a lipid P composition associated with a heightened atherogenic risk and greater tendency toward insulin resistance by the Lipoprotein-Insulin Resistance (LP-IR) score. In the SCI-Low group, the decreased number and reduced size of lipoprotein P were more prevalent and may be associated with increased waist circumference (i.e., abdominal adiposity), relatively elevated TG values (compared to the other subgroups), and an underlying subclinical state of insulin resistance.

CONCLUSIONS

Prolonged sitting and restricted physical activity in individuals with SCI had the most profound effect on the HDL-C and its lipoprotein P subclasses, but not on LDL-C, however its P subclasses were also unfavorably affected but not to the same degree. The quantification of lipoprotein P characteristics may be a potent tool for the determination of risk for CVD in persons with SCI.

Acute Cardiorespiratory and Metabolic Responses During Exoskeleton-Assisted Walking Overground Among Persons with Chronic Spinal Cord Injury

BACKGROUND

Lower extremity robotic exoskeleton technology is being developed with the promise of affording people with spinal cord injury (SCI) the opportunity to stand and walk. The mobility benefits of exoskeleton-assisted walking can be realized immediately, however the cardiorespiratory and metabolic benefits of this technology have not been thoroughly investigated.

OBJECTIVE

The purpose of this pilot study was to evaluate the acute cardiorespiratory and metabolic responses associated with exoskeleton-assisted walking overground and to determine the degree to which these responses change at differing walking speeds.

METHODS

Five subjects (4 male, 1 female) with chronic SCI (AIS A) volunteered for the study. Expired gases were collected during maximal graded exercise testing and two, 6-minute bouts of exoskeleton-assisted walking overground. Outcome measures included peak oxygen consumption (V̇O2peak), average oxygen consumption (V̇O2avg), peak heart rate (HRpeak), walking economy, metabolic equivalent of tasks for SCI (METssci), walk speed, and walk distance.

RESULTS

Significant differences were observed between walk-1 and walk-2 for walk speed, total walk distance, V̇O2avg, and METssci. Exoskeleton-assisted walking resulted in %V̇O2peak range of 51.5% to 63.2%. The metabolic cost of exoskeleton-assisted walking ranged from 3.5 to 4.3 METssci.

CONCLUSIONS

Persons with motor-complete SCI may be limited in their capacity to perform physical exercise to the extent needed to improve health and fitness. Based on preliminary data, cardiorespiratory and metabolic demands of exoskeleton-assisted walking are consistent with activities performed at a moderate intensity.

Serum lipid profile in subjects with traumatic spinal cord injury

Background and Aims

Few large studies have examined the relationship between spinal cord injury (SCI) and lipid profile. We studied serum lipid concentrations in subjects with traumatic SCI in relation to the degree of neurological involvement and time since injury, and compared them with values from a reference sample for the Spanish population (DRECE study).

Materials and Methods

A retrospective cohort was built from 177 consecutive cases with traumatic SCI admitted to the SCI unit of the Miguel Servet Hospital in Aragon (Spain). Outcome measures (cholesterol, triglycerides, HDL-c and LDL-c levels) were analyzed according to the ASIA Impairment Scale (AIS), neurological level of injury (involvement of all limbs vs. only lower limbs), and time since injury. All analyses were adjusted for age and sex.

Results

Cases without preserved motor function (AIS A or B) had lower total and HDL cholesterol than the others (-11.4 [-21.5, -1.4] mg/dL total cholesterol and -5.1 [-8.8, -1.4] mg/dL HDL-c), and cases with all-limb involvement had lower total, HDL, and LDL cholesterol than those with only lower-limb involvement (-14.0 [-24.6, -3.4] mg/dL total cholesterol, -4.1 [-8.0, -0.2] mg/dL HDL-c, and -10.0 [-19.7, -0.3] mg/dL LDL-c) (all p<0.05). No association was found between lipid concentrations and time since injury. Concentrations of lipid subfractions and triglycerides in SCI subjects were lower than in sex- and age-stratified values from the reference sample.

Conclusion

A high degree of neurological involvement in SCI (anatomically higher lesions and AIS A or B) is associated with lower total cholesterol and HDL-c.