Measurement of coronary artery calcification by electron beam computerized tomography in persons with chronic spinal cord injury: evidence for increased atherosclerotic burden

Development of a Hypercoagulable-Hypofibrinolytic State Early After Spinal Cord Injury

OBJECTIVES

To determine whether spinal cord injury (SCI) is associated with adverse changes in coagulation and fibrinolytic factors that underlie thrombogenesis and contribute to atherothrombotic events such as myocardial infarctions (MIs) and strokes.

DESIGN

Cross-sectional study.

SETTING

Neurorehabilitation hospital and general community.

PARTICIPANTS

Thirty young and middle-aged (20-58 years) adults (N=30) were studied: 14 non-injured community dwelling adults. (11M/4F) and 16 with subacute tetraplegic motor complete SCI during initial inpatient rehabilitation (13M/3F; time since injury: 11.8±5.3 wk).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Circulating markers of coagulation [von Willebrand factor (vWf) and factors VII, VIII, and X], the fibrinolytic system [tissue-type plasminogen activator (t-PA), and plasminogen activator inhibitor-1 (PAI-1) antigen and activity], and fibrin formation (D-dimer) were determined by enzyme immunoassay.

RESULTS

Thirty young and middle-aged (20-58 years) adults were studied: 14 non-injured (11M/4F) and 16 with subacute tetraplegic motor complete SCI (13M/3F; time since injury: range 4-25 wk). Circulating levels of coagulation factors VII, VIII, and X were significantly higher (∼20%-45%; P<.05) in the adults with SCI than non-injured adults, whereas vWf was similar between groups. Fibrinolytic markers were adversely disrupted with SCI with t-PA antigen, PAI-1 antigen and PAI-1 activity were markedly higher (∼50%-800%; P<.05) in adults with SCI compared with non-injured adults. The molar concentration ratio of active t-PA to PAI-1 was significantly higher (∼350%) in adults with SCI. Concordant with coagulation cascade activation and fibrinolytic system inhibition, D-dimer concentrations were markedly ∼70% higher (P<.05) in adults with SCI compared with non-injured adults.

CONCLUSIONS

Subacute tetraplegic motor complete SCI is associated with a prothrombotic hemostatic profile. Adverse changes in the coagulation cascade and fibrinolytic system appear to occur early after injury and may contribute to the increased atherothrombotic risk in adults living with SCI.

Coronary and carotid imaging of atherosclerosis and contributing factors in middle-aged people with long-term cervical and upper thoracic spinal cord injuries

BACKGROUND

Cardiovascular disease is a major cause of death in people aging with spinal cord injury (SCI) and is predominantly caused by atherosclerosis; however, knowledge of atherosclerosis in people with SCI is scarce.

OBJECTIVE

To describe coronary and carotid atherosclerosis in middle-aged people with long-term cervical and upper thoracic SCI using coronary computed tomography angiography, carotid ultrasound, and cardiovascular disease risk factors and to compare with the general population.

DESIGN

Cross-sectional study with matched controls.

SETTING

Outpatient SCI unit in southern Sweden.

PARTICIPANTS

Participants (n = 25) in the Swedish SPinal Cord Injury Study on Cardiopulmonary and Autonomic Impairment (SPICA) (20% women, mean age 58 years, mean time since injury 28 years, injury levels C2-T6, American Spinal Injury Association Impairment Scale A-C). Non-SCI controls (n = 125; ratio 5:1) from the Swedish CArdioPulmonary bioImage Study (SCAPIS).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASUREMENTS

Presence of coronary atherosclerosis, coronary artery calcium score, carotid plaques, carotid intima media thickness, blood pressure, lipids, Systematic Coronary Risk Evaluation (SCORE), and anthropometry.

RESULTS

Coronary and carotid atherosclerotic plaques occurred in 44% of the participants, 67% of the controls exhibited coronary and 59% carotid plaques; odds ratios (OR; 95% confidence interval [CI]): 0.38 (0.13-1.17) and 0.54 (0.22-1.32), respectively. Mean number of segments with coronary atherosclerosis were 1.0 in participants and 2.1 in controls (OR: 0.74 [0.52-1.06]). Coronary artery calcium score > 100 occurred in 4 (18%) of the participants and 23 (21%) of the controls. The participants had significantly lower levels of total and non-high density lipoprotein cholesterol and SCORE than the controls.

CONCLUSIONS

This is the first comprehensive assessment of atherosclerosis in people with SCI using advanced imaging techniques. The atherosclerotic burden in middle-aged people with long-term cervical and upper thoracic SCI was not increased, whereas SCORE was lower due to lower cholesterol levels. Imaging techniques may be valuable tools for assessment of atherosclerosis in SCI.

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.

Diagnosis and Management of Cardiovascular Risk in Individuals With Spinal Cord Injury: A Narrative Review

More than 16 000 Americans experience spinal cord injury (SCI), resulting in chronic disability and other secondary sequelae, each year. Improvements in acute medical management have increased life expectancy. Cardiovascular disease is a leading cause of death in this population, and seems to occur earlier in individuals with SCI compared with the general population. People with SCI experience a high burden of traditional cardiovascular disease risk factors, including dyslipidemia and diabetes, and demonstrate anatomic, metabolic, and physiologic changes alongside stark reductions in physical activity after injury. They also experience multiple, complex barriers to care relating to disability and, in many cases, compounding effects of intersecting racial and socioeconomic health inequities. Given this combination of risk factors, some investigators have proposed that people with SCI are at increased risk for cardiovascular disease, beyond that associated with traditional risk factors, and SCI could be considered a risk-enhancing factor, analogous to other risk-enhancing factors defined by the 2019 American Heart Association/American College of Cardiology Primary Prevention Guidelines. However, more research is needed in this population to clarify the role of traditional risk factors, novel risk factors, health care access, social determinants of health, and intersectionality of disability, race, and socioeconomic status. There is an urgent need for primary care physicians and cardiologists to have awareness of the importance of timely diagnosis and management of cardiac risk factors for people with SCI.

Differential Expression of Vascular-Related MicroRNA in Circulating Endothelial Microvesicles in Adults With Spinal Cord Injury: A Pilot Study

Background

Spinal cord injury (SCI) is associated with an increased risk and prevalence of cardiopulmonary and cerebrovascular disease-related morbidity and mortality. The factors that initiate, promote, and accelerate vascular diseases and events in SCI are poorly understood. Clinical interest in circulating endothelial cell-derived microvesicles (EMVs) and their microRNA (miRNA) cargo has intensified due to their involvement in endothelial dysfunction, atherosclerosis, and cerebrovascular events.

Objectives

The aim of this study was to determine whether a subset of vascular-related miRNAs is differentially expressed in EMVs isolated from adults with SCI.

Methods

We assessed eight adults with tetraplegia (7 male/1 female; age: 46±4 years; time since injury: 26±5 years) and eight uninjured (6 male/2 female; age: 39±3 years). Circulating EMVs were isolated, enumerated, and collected from plasma by flow cytometry. The expression of vascular-related miRNAs in EMVs was assessed by RT-PCR.

Results

Circulating EMV levels were significantly higher (~130%) in adults with SCI compared with uninjured adults. The expression profile of miRNAs in EMVs from adults with SCI were significantly different than uninjured adults and were pathologic in nature. Expression of miR-126, miR-132, and miR-Let-7a were lower (~100-150%; p < .05), whereas miR-30a, miR-145, miR-155, and miR-216 were higher (~125-450%; p < .05) in EMVs from adults with SCI.

Conclusion

This study is the first examination of EMV miRNA cargo in adults with SCI. The cargo signature of vascular-related miRNAs studied reflects a pathogenic EMV phenotype prone to induce inflammation, atherosclerosis, and vascular dysfunction. EMVs and their miRNA cargo represent a novel biomarker of vascular risk and a potential target for intervention to alleviate vascular-related disease after SCI.

Increased risk of sensorineural hearing loss in patients with spinal cord injury: a nationwide longitudinal follow-up study

STUDY DESIGN

Retrospective cohort study with 10 years follow-up.

OBJECTIVE

To compare the risks of sensorineural hearing loss in patients with and without spinal cord injury, based on a nationally representative sample.

SETTING

Taiwan's Longitudinal Health Insurance Database 2005.

METHOD

A total of 2006 participants who had been aged between 20 and 69 and who had spinal cord injury as of 2002-06 were enrolled in the spinal cord injury group. The non-spinal cord injury group consisted of 8024 sex- and age-matched, randomly sampled participants without spinal cord injury. Then, their sensorineural hearing loss -cumulative incidence curves were generated using the Kaplan-Meier method. Stratified Cox proportional-hazard regression was employed to estimate the effect of having spinal cord injury on patients' subsequent risk of sensorineural hearing loss.

RESULTS

During the follow-up, 30 patients in the spinal cord injury group and 87 in the non-spinal cord injury group developed sensorineural hearing loss. As such, the cumulative incidence of sensorineural hearing loss was significantly higher in the spinal cord injury group than the non-spinal cord injury group (2.16 vs. 1.21 per 1000 person-years, p = 0.008). The adjusted hazard ratio of sensorineural hearing loss for the spinal cord injury group was 1.75 times that of the non-spinal cord injury group (95% CI, 1.14-2.68, p = 0.01). The patients with non-cervical SCI appeared to have a higher magnitude of SNHL risk than their cervical SCI counterparts.

CONCLUSION

Our study showed that patients with spinal cord injury have an increased risk of developing sensorineural hearing loss.

The neurological level of spinal cord injury and cardiovascular risk factors: a systematic review and meta-analysis

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVE

To determine the difference in cardiovascular risk factors (blood pressure, lipid profile, and markers of glucose metabolism and inflammation) according to the neurological level of spinal cord injury (SCI).

METHODS

We searched 5 electronic databases from inception until July 4, 2020. Data were extracted by two independent reviewers using a pre-defined data collection form. The pooled effect estimate was computed using random-effects models, and heterogeneity was calculated using I² statistic and chi-squared test (CRD42020166162).

RESULTS

We screened 4863 abstracts, of which 47 studies with 3878 participants (3280 males, 526 females, 72 sex unknown) were included in the meta-analysis. Compared to paraplegia, individuals with tetraplegia had lower systolic and diastolic blood pressure (unadjusted weighted mean difference, -14.5 mmHg, 95% CI -19.2, -9.9; -7.0 mmHg 95% CI -9.2, -4.8, respectively), lower triglycerides (-10.9 mg/dL, 95% CI -19.7, -2.1), total cholesterol (-9.9 mg/dL, 95% CI -14.5, -5.4), high-density lipoprotein (-1.7 mg/dL, 95% CI -3.3, -0.2) and low-density lipoprotein (-5.8 mg/dL, 95% CI -9.0, -2.5). Comparing individuals with high- vs. low-thoracic SCI, persons with higher injury had lower systolic and diastolic blood pressure (-10.3 mmHg, 95% CI -13.4, -7.1; -5.3 mmHg 95% CI -7.5, -3.2, respectively), while no differences were found for low-density lipoprotein, serum glucose, insulin, and inflammation markers. High heterogeneity was partially explained by age, prevalent cardiovascular diseases and medication use, body mass index, sample size, and quality of studies.

CONCLUSION

In SCI individuals, the level of injury may be an additional non-modifiable cardiovascular risk factor. Future well-designed longitudinal studies with sufficient follow-up and providing sex-stratified analyses should confirm our findings and explore the role of SCI level in cardiovascular health and overall prognosis and survival.

The Swedish SPinal Cord Injury Study on Cardiopulmonary and Autonomic Impairment: Methodology, Cohort Demographics, and Initial Results

OBJECTIVE

The aim of the study was to present the methodology, cohort demographics, and initial results of the Swedish SPinal Cord Injury Study on Cardiopulmonary and Autonomic Impairment (SPICA).

DESIGN

The SPICA is based on the Swedish CArdioPulmonary BioImage Study, a study on cardiopulmonary diseases in a cohort of 30,000 people. The assessments in the SPICA cover the structure and function of the cardiopulmonary and autonomic systems using bioimaging and functional analyses, together with a study-specific questionnaire and generic and spinal cord injury-specific assessment tools. The inclusion criteria were as follows: age 50-65 yrs, traumatic spinal cord injury of 5 yrs or more, and injury levels C1-T6, American Spinal Injury Association Impairment Scale A-C.

RESULTS

Of 38 potential participants, 25 comprised the final sample (20% women, mean age 58 yrs, mean time since injury 28 yrs). Eight percent had sustained a cardiovascular event, and 72% were classified as a high risk for cardiovascular disease. Asthma was previously diagnosed in only 8%, and none had chronic obstructive pulmonary disease.

CONCLUSIONS

The risk for cardiovascular disease in people with severe high-level spinal cord injury is a major clinical concern. Forthcoming studies in the SPICA will provide new knowledge of cardiopulmonary health in this cohort, which can guide future research and be used to develop long-term management.

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.

Guideline for the identification and management of cardiometabolic risk after spinal cord injury: a case of unsubstantiated recommendations

The 2018 Guideline for the Identification and Management of Cardiometabolic Risk after Spinal Cord Injury (SCI) represented the first concerted effort to address a cluster of derangements and diseases that are claiming the lives of individuals living with injuries. Its contributors and authors scoured the literature, weighed the validity, importance, and clinical relevance of what data they found, and collaborated in an effort to meaningfully improve the health and lives of people with SCI. However, we are concerned that several of the guideline's central recommendations-particularly around screening for and detection of glycemic dysregulation and dyslipidemia-have been offered prematurely. In several instances, the authors cite data from studies of people without SCI and, in our opinion, inappropriately apply those findings to support their SCI-specific suggestions. In other instances, they recommend that we employ tests whose usefulness and clinical relevance have yet to be demonstrated among people living with injuries. In short, we fear that the authors have developed clinical guidelines that are inadequately supported by data. This guideline is an extraordinary show of collaboration, and is an important first step toward understanding and treating a number of secondary cardiometabolic effects of SCI. The lack of data underpinning several of its central recommendations-making them, in our opinion, unadoptable-underscores the inadequacy of research in this area and provides a roadmap for future investigative efforts.

Effects of Intermittent Pneumatic Compression on Leg Vascular Function in People with Spinal Cord Injury: A Pilot Study

Objective: The purpose of this pilot study was to determine whether 60 mins of intermittent pneumatic compression therapy (IPC) could acutely increase leg blood flow-induced shear stress and enhance vascular endothelial function in persons with spinal cord injury (SCI). Design: Pretest with multiple posttests, within subject randomized control design. Setting: University of Southern Mississippi, Spinal Cord Injury Research Program within the School of Kinesiology, recruiting from the local community in Hattiesburg, Jackson, and Gulfport, MS. Participants: Eight adults with SCI (injury level: T3 and below; ASIA class A-C; age: 41±17 yrs). Interventions: A 60-min IPC session was performed in one leg (experimental leg; EXP), with the other leg serving as a control (CON). Outcomes Measures: Posterior-tibial artery shear rate (Doppler-ultrasound) was examined at rest, and at 15 and 45 mins during IPC. Endothelial function was assessed using the flow-mediated dilation (FMD) technique, before and after IPC. Results: Resting FMD (mm) was similar between legs at rest. A two-way repeated measures ANOVA (leg x time) revealed that during IPC, peak shear rate increased in the EXP leg (215±137 to 285±164 s^-1 at 15 mins; +39±29%, P = 0.03), with no change occurring in the CON. In addition, FMD significantly increased in the EXP leg (Pre IPC: 0.36±0.14 vs. Post IPC: 0.47±0.17 mm; P = 0.011, d = 0.66), with no change occurring in the CON leg. Conclusion: These preliminary findings suggests that IPC therapy may acutely increase leg shear stress within 15 mins, with a resultant moderate-large improvement in vascular endothelial function after 60 mins in people with SCI.

Circulating microRNAs, Vascular Risk, and Physical Activity in Spinal Cord-Injured Subjects

The aim of this study was to compare the expression of serum microRNAs (miRNAs) in individuals with spinal cord injury (SCI) (athletes [SCI-A] and sedentary [SCI-S]) and able-bodied (AB) individuals, and investigate the relationship of miRNAs with carotid intima-media thickness (cIMT) and serum oxidized LDL-cholesterol (oxLDL) among SCI subjects. Seventeen SCI-S, 23 SCI-A, and 22 AB males were evaluated by clinical and laboratory analysis, and had oxLDL and cIMT measured by enzyme-linked immunosorbent assay (ELISA) and ultrasonography, respectively. A total of 754 miRNAs were measured using a TaqMan OpenArray^® Human MicroRNA system. SCI-S subjects had higher cIMT and oxLDL than SCI-A and AB. Compared with AB, only one miRNA was differently expressed in both SCI-A and SCI-S individuals, whereas 25 miRNAs were differently expressed in SCI-S, but not in SCI-A. Of these 25 miRNAs, 22 showed different expression between SCI-S and SCI-A. Several miRNAs correlated with oxLDL and cIMT among all SCI individuals. Notably, miR-125b-5p, miR-146a-5p, miR-328-3p, miR-191-5p, miR-103a-3p, and miR-30b-5p correlated with both oxLDL and cIMT, and showed distinct expression between the SCI-A and SCI-S groups. Gene set enrichment analysis demonstrated that miRNAs related to cIMT and oxLDL may be involved in molecular pathways regulating vascular function and remodeling. In conclusion, this exploratory analysis suggests that variations in circulating miRNA expression in individuals with SCI compared with AB subjects are markedly attenuated by regular physical activity. Several miRNAs may be involved in physical activity-related improvements in vascular risk and remodeling among SCI individuals.

Quality reporting of carotid intima-media thickness methodology; Current state of the science in the field of spinal cord injury

OBJECTIVES

Carotid intima-media thickness (cIMT) may be used increasingly as a cardiovascular disease (CVD) screening tool in individuals with spinal cord injury (SCI) as other routine invasive diagnostic tests are often unfeasible. However, variation in cIMT acquisition and analysis methods is an issue in the current published literature. The growth of the field is dependent on cIMT quality acquisition and analysis to ensure accurate reporting of CVD risk. The purpose of this study is to evaluate the quality of the reported methodology used to collect cIMT values in SCI.

METHODS

Data from 12 studies, which measured cIMT in individuals with SCI, were identified from the Medline, Embase and CINAHL databases. The quality of the reported methodologies was scored based on adherence to cIMT methodological guidelines abstracted from two consensus papers.

RESULTS

Five studies were scored as 'moderate quality' in methodological reporting, having specified 9 to 11 of 15 quality reporting criterion. The remaining seven studies were scored as 'low quality', having reported less than 9 of 15 quality reporting criterion. No study had methodological reporting that was scored as 'high quality'. The overall reporting of quality methodology was poor in the published SCI literature.

CONCLUSIONS

A greater adherence to current methodological guidelines is needed to advance the field of cIMT in SCI. Further research is necessary to refine cIMT acquisition and analysis guidelines to aid authors designing research and journals in screening manuscripts for publication.

Fundamental hemodynamic mechanisms mediating the response to myocardial ischemia in conscious paraplegic mice: cardiac output versus peripheral resistance

Autonomic dysfunction, a relative sedentary lifestyle, a reduced muscle mass and increased adiposity leads to metabolic abnormalities that accelerate the development of coronary artery disease (CAD) in individuals living with spinal cord injury (SCI). An untoward cardiac incident is related to the degree of CAD, suggesting that the occurrence of a significant cardiac event is significantly higher for individuals with SCI. Thus, understanding the fundamental hemodynamic mechanisms mediating the response to myocardial ischemia has the potential to positively impact individuals and families living with SCI. Accordingly, we systematically investigated if thoracic level 5 spinal cord transection (T₅X; paraplegia) alters the arterial blood pressure response to coronary artery occlusion and if the different arterial blood pressure responses to coronary artery occlusion between intact and paraplegic mice are mediated by changes in cardiac output and or systemic peripheral resistance and whether differences in cardiac output are caused by changes in heart rate and or stroke volume. To achieve this goal, the tolerance to 3 min of coronary artery occlusion was determined in conscious intact and paraplegic mice. Paraplegic mice had an impaired ability to maintain arterial blood pressure during coronary artery occlusion as arterial pressure fell to near lethal levels by 1.38 ± 0.64 min. The lower arterial pressure was mediated by a lower cardiac output as systemic peripheral resistance was elevated in paraplegic mice. The lower cardiac output was mediated by a reduced heart rate and stroke volume. These results indicate that in paraplegic mice, the arterial pressure response to coronary artery occlusion is hemodynamically mediated primarily by cardiac output which is determined by heart rate and stroke volume.

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.

Robotically assisted treadmill exercise training for improving peak fitness in chronic motor incomplete spinal cord injury: A randomized controlled trial

OBJECTIVE

To assess the effectiveness of robotically assisted body weight supported treadmill training (RABWSTT) for improving cardiovascular fitness in chronic motor incomplete spinal cord injury (CMISCI).

DESIGN

Pilot prospective randomized, controlled clinical trial.

SETTING

Outpatient rehabilitation specialty hospital.

PARTICIPANTS

Eighteen individuals with CMISCI with American Spinal Injury Association (ASIA) level between C4 and L2 and at least one-year post injury. Interventions CMISCI participants were randomized to RABWSTT or a home stretching program (HSP) three times per week for three months. Those in the home stretching group were crossed over to three months of RABWSTT following completion of the initial three month phase.

OUTCOME MEASURES

Peak oxygen consumption (peak VO(2)) was measured during both robotic treadmill walking and arm cycle ergometry: twice at baseline, once at six weeks (mid-training) and twice at three months (post-training). Peak VO(2) values were normalized for body mass.

RESULTS

The RABWSTT group improved peak VO(2) by 12.3% during robotic treadmill walking (20.2 ± 7.4 to 22.7 ± 7.5 ml/kg/min, P = 0.018), compared to a non-significant 3.9% within group change observed in HSP controls (P = 0.37). Neither group displayed a significant change in peak VO2 during arm cycle ergometry (RABWSTT, 8.5% (P = 0.25); HSP, 1.76% (P = 0.72)). A repeated measures analysis showed statistically significant differences between treatments for peak VO(2) during both robotic treadmill walking (P = 0.002) and arm cycle ergometry (P = 0.001).

CONCLUSION

RABWSTT is an effective intervention model for improving peak fitness levels assessed during robotic treadmill walking in persons with CMISCI.

Bowel dysfunction in spinal cord injury: current perspectives

Permanent disruptions of gastrointestinal function are very common sequel of spinal cord injury (SCI). When motor and sensory nervous integrity are severely affected, neurogenic gastrointestinal dysfunction is an inevitable consequence. Autonomic nervous system miss function has significantly diminished or lost sensory sensations followed with incomplete evacuation of stool from the rectal vault, immobility, and reduced anal sphincter tone all of those predisposing to increased risk of fecal incontinence (FI). The FI is, beside paralysis of extremities, one of the symptoms most profoundly affecting quality of life (QOL) in patients with SCI. We are reviewing current perspectives in management of SCI, discussing some pathophysiology mechanisms which could be addressed and pointing toward actual practical concepts in use for evaluation and improvements necessary to sustain SCI patients QOL.

Lean tissue mass and energy expenditure are retained in hypogonadal men with spinal cord injury after discontinuation of testosterone replacement therapy

OBJECTIVE

To determine whether favorable changes to lean tissue mass (LTM), resting energy expenditure (REE), and testosterone (T) that occurred with 12 months of physiological testosterone replacement therapy (TRT) were retained 6 months after discontinuing treatment.

DESIGN

Prospective, open-label, controlled drug intervention trial.

SETTING

Metropolitan area hospitals.

SUBJECTS

Eugonadal (n = 11) and hypogonadal (n = 13) men with chronic spinal cord injury (SCI).

INTERVENTIONS

Hypogonadal subjects received a 5 or 10 mg transdermal T patch daily for 12 months, with adjustment of the dose to normalize the serum T concentration; TRT was discontinued after 12 months (TRT-12M) and subjects were followed for an additional 6 months and re-evaluated (Post-TRT). Total body dual energy X-ray absorptiometry and blood draws were performed at baseline (BL) prior to TRT, TRT-12M, and Post-TRT. Eugonadal subjects did not receive treatment and were evaluated at comparable time points.

RESULTS

There were no significant differences between groups prior to TRT at BL for any of the study endpoints. In the hypogonadal group, a significant increase in LTM was observed from BL to TRT-12M (50.2 ± 7.4 vs. 52.9 ± 6.8 kg, P < 0.01), which persisted Post-TRT compared to BL (52.2 ± 7.8 kg, P < 0.05). The increase in REE from BL to TRT-12M (1283 ± 246 vs. 1410 ± 250 kcal/day) was also retained at Post-TRT (1393 ± 220 kcal/day). These sustained improvements in LTM and REE after termination of anabolic hormonal therapy may be associated with persistent beneficial effects on health and physical function of hypogonadal men with chronic SCI.

Predictors of subclinical atherosclerosis in women with spinal cord injury

BACKGROUND

Chronic spinal cord injury (SCI) is associated with an increase in risk factors for cardiovascular disease (CVD). In the general population, atherosclerosis in women occurs later than in men and usually presents differently. Associations between risk factors and incidence of CVD have not been studied in women with SCI.

OBJECTIVE

To determine which risk factors for CVD are associated with increased carotid intima-media thickness (CIMT), a common indicator of atherosclerosis, in women with SCI.

METHODS

One hundred and twenty-two females older than 18 years with traumatic SCI at least 2 years prior to entering the study were evaluated. Participants were asymptomatic and without evidence of CVD. Exclusion criteria were acute illness, overt heart disease, diabetes, and treatment with cardiac drugs, lipid-lowering medication, or antidiabetic agents. Measures for all participants were age, race, smoking status, level and completeness of injury, duration of injury, body mass index, serum lipids, fasting glucose, hemoglobin A1c, and ultrasonographic measurements of CIMT. Hierarchical multiple linear regression was conducted to predict CIMT from demographic and physiologic variables.

RESULTS

Several variables were significantly correlated with CIMT during univariate analyses, including glucose, hemoglobin A1c, age, and race/ethnicity; but only age was significant in the hierarchical regression analysis.

CONCLUSIONS

Our data indicate the importance of CVD in women with SCI.

The relationship between the postprandial lipemic response and lipid composition in persons with spinal cord injury

OBJECTIVE

To determine the influence of lipid concentration, lipid particle size, and total abdominal fat (TAF) on postprandial lipemic response (PPLr) in persons with spinal cord injury (SCI).

METHODS

Thirty-five persons with SCI (17 paraplegia, 18 tetraplegia) and 18 able-bodied (AB) individuals participated. Following a 10-hour fast, blood was drawn for lipids, apolipoprotein (apo) A1 and B concentrations, and low-density (LSP) and high-density (HSP) lipoprotein particle sizes. A high-fat milkshake was consumed (∼1.3 g fat/kg). Blood was drawn at 2, 4, and 6 hours to determine PPLr, (triglyceride (TG) area under the curve). TAF and visceral (VF) fat were measured by ultrasonography; total body fat (TBF) by dual-energy X-ray absorptiometry. Differences between the groups were determined by independent sample t-tests. Pearson correlation coefficients determined the relationship among PPLr and lipids, and TAF.

RESULTS

There were no significant differences in fasting TG, low-density lipoprotein (LDL), apoB, TAF, or PPLr values between the groups. In SCI, PPLr significantly correlated with: apoB (r = 0.63, P < 0.01, LSP (r = 0.57, P < 0.01), and TAF (r = 0.36, P < 0.01). After controlling for age and duration of injury, PPLr significantly correlated with apoB (r = 0.66, P = 0.001), TBF (r = 0.45, P = 0.03), VF (r = 0.66, P = 0.02), and TAF (r = 0.56, P = 0.007).

CONCLUSIONS

Although concentrations of LDL cholesterol and apoB were not different between SCI and AB groups, LSP, apoB, and TAF correlated with PPLr in persons with SCI. ApoB was associated with a greater PPLr in those with motor complete SCI, after controlling for age and duration of injury.

Oxidized low-density lipoprotein, matrix-metalloproteinase-8 and carotid atherosclerosis in spinal cord injured subjects

OBJECTIVE

Previous reports have indicated that subjects with chronic spinal cord injury (SCI) exhibit increased cardiovascular risk compared to able-bodied individuals. This study investigated the relationship between plasmatic oxidized low-density lipoprotein (OxLDL), matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) levels and vascular remodeling in SCI subjects and the role of physical activity in this regard.

METHODS

We studied 42 men with chronic (≥2 years) SCI [18 sedentary (S-SCI) and 24 physically active (PA-SCI)] and 16 able-bodied men by clinical, anthropometric, laboratory, and carotid intima-media thickness (IMT) analysis. All enrolled subjects were normotensive, non-diabetics, non-smokers and normolipemic. Plasmatic OxLDL, MMP-2, MMP-8, MMP-9, TIMP-1 and TIMP-2 levels were determined by enzyme-linked immunosorbent assay.

RESULTS

Carotid IMT, IMT/diameter ratio and OxLDL levels of PA-SCI and able-bodied subjects were statistically similar. Conversely, S-SCI subjects exhibited higher IMT, IMT/diameter ratio and OxLDL levels compared to PA-SCI (p < 0.01, p < 0.001 and p = 0.01, respectively) and able-bodied (p < 0.001 for all) individuals. Results of bivariate correlation analysis including all injured subjects showed that carotid IMT and IMT/diameter ratio only correlated with OxLDL, MMP-8 and MMP-8/TIMP-1 ratio. Further stepwise regression analysis adjusted for the presence or not of physical activity and age showed that OxLDL was associated with carotid IMT and IMT/diameter ratio, while MMP-8 was associated with IMT/diameter ratio in SCI individuals.

CONCLUSIONS

Plasmatic OxLDL and MMP-8 levels are associated with carotid atherosclerosis and there is an interaction among physical inactivity, atherosclerosis and OxLDL in SCI individuals.

Baseline prevalence of heart diseases, hypertension, diabetes, and obesity in persons with acute traumatic spinal cord injury: potential threats in the recovery trajectory

BACKGROUND

Chronic diseases impede the recovery trajectory of acutely injured persons with traumatic spinal cord injury (TSCI). This study compares the odds of prevalent heart disease, hypertension, diabetes mellitus, and obesity between persons with TSCI and persons with lower extremity fractures (LEF) who were discharged from acute care facilities.

METHODS

1,776 patients with acute TSCI (cases) and 1,780 randomly selected patients with LEF (controls) discharged from January 1, 1998, through December 31, 2009, from all nonfederal hospitals were identified. Data extracted from uniform billing files were compared between cases and controls in a multivariable logistic regression model controlling for sociodemographic and clinical covariables.

RESULTS

Thirty percent of patients with acute TSCI had at least 1 of 4 conditions compared with 18% of patients with LEF (P < .0001). Persons with acute TSCI were 4 times more likely (odds ratio [OR], 4.05; 95% CI, 1.65-9.97) to have obesity, 2.7 times more likely to have heart disease (P < .001), 2 times more likely to have hypertension (P < .001), and 1.7 times more likely to have diabetes (P = .044) at the onset of TSCI. Disproportionately more Blacks than Whites have TSCI and chronic diseases.

CONCLUSION

This study suggests that there is an increased burden of cardiovascular and cardiometabolic diseases among persons with acute TSCI compared with LEF trauma controls. Unattended comorbid conditions will affect quality of life and the recovery process. This warrants continuous monitoring and management of chronic diseases during the rehabilitation process.

Characteristics of abdominal obesity in persons with spinal cord injury

Objective

To investigate the characteristics of community-dwelling spinal cord injury (SCI) persons with obesity, including diet, socioeconomic factors, weight reduction method, and frequency of body weight and abdominal circumference measurements.

Methods

We developed a questionnaire based on 'the Fourth Korea National Health and Nutrition Examination Survey, 2009'. A total of 371 community-dwelling SCI persons were enrolled in this study. Inclusion criteria were SCI persons older than 20 years with more than 1 year elapsed since the injury. Trained investigators visited SCI persons' home to complete the questionnaire and measure abdominal obesity (AO) as defined by the waist circumference.

Results

Prevalence of AO was 29.2% in SCI persons and 27.4% in the general population (GP), showing no significant difference. Education showed correlation with AO in both SCI persons and the GP. The injury level, type of injury and income did not show any correlation with AO in SCI persons. Only 28.8% and 48.8% of SCI persons measured their waist circumference and body weight within the past year, respectively. Also, SCI persons with AO thought that their body was less obese compared to persons with AO in the GP (p<0.001). The method of weight reduction was diet modification in 53.6% of SCI persons with AO, which was higher than 37.1% of persons with AO in the GP.

Conclusion

In SCI persons, obesity perception as well as socioeconomic factors correlated with AO, but these were not relevant factors in the GP. Therefore, development of a specific and intensive weight control program for SCI persons is necessary.

H-FABP, cardiovascular risk factors, and functional status in asymptomatic spinal cord injury patients

BACKGROUND

This was a cross-sectional study in the setting of a rehabilitation hospital.

OBJECTIVE

The aim of the study was to determine the serum levels of heart-type fatty acid-binding protein (H-FABP) in patients with spinal cord injury (SCI). A further goal was to examine whether there is a relationship between H-FABP levels and Functional Ambulation Classification (FAC) scale, Functional Independence Measure (FIM) score, American Spinal Injury Association (ASIA) status, and metabolic syndrome (MetS).

METHODS

The study included 56 SCI patients and 37 age- and sex-matched healthy control subjects who had not been diagnosed with coronary artery disease in the past.

RESULTS

Serum H-FABP levels were significantly higher in patients with SCI than in control subjects: paraplegia group, 18.5  ±  11.4; tetraplegia group, 16.3  ±  9.1; control group, 6.7 ± 5.1 ng/ml (p < 0.001). There was no difference between the other cardiac enzymes (troponin I, AST, ALT, CK, CK-MB, and LDH) among the groups. The relationship between the serum H-FABP levels and FAC status was examined. There was a negative correlation between FAC status and H-FABP levels (p < 0.001, r = - 0.581). Patients with complete SCI were divided into two groups according to the level of the lesion: (lesion levels in C6-T6, n = 25; lesion levels in T7-L2, n = 11). In patients with complete motor injury, H-FABP levels were higher in subjects with injuries above T6 than in those with injuries below T6 (24.21 ± 10.1 and 14.1 ± 10.4, respectively; p = 0.011). Serum levels of H-FABP were higher in SCI patients with MetS (n = 10) than in those without MetS (n = 46; 25.8  ±  11.6 ng/ml vs. 16.42 ± 10.3 ng/ml, respectively; p = 0.014). Patients were then divided into two groups according to SCI duration: <  12 months (n = 27) and > 12 months (n = 29). H-FABP levels showed statistically significant differences between the two groups (14.8 ± 11.7 ng/dl and 20.9  ±  9.9 ng/dl, respectively; p = 0.036).

CONCLUSION

H-FABP is related to MetS and FAC status in asymptomatic SCI patients.

31st g. Heiner sell lectureship: secondary medical consequences of spinal cord injury

Persons with spinal cord injury (SCI) have secondary medical consequences of paralysis and/or the consequences of extreme inactivity. The metabolic changes that result from reduced activity include insulin resistance with carbohydrate disorders and dyslipidemia. A higher prevalence of coronary artery calcification was found in persons with SCI than that in matched able-bodied controls. A depression in anabolic hormones, circulating testosterone and growth hormone, has been described. Adverse soft tissue body composition changes of increased adiposity and reduced skeletal muscle are appreciated. Immobilization is the cause for sublesional disuse osteoporosis with an associated increased risk of fragility fracture. Bowel dysmotility affects all segments of the gastrointestinal tract, with an interest in better defining and addressing gastroesophageal reflux disease and difficulty with evacuation. Developing and testing more effective approaches to cleanse the bowel for elective colonoscopy are being evaluated. The extent of respiratory dysfunction depends on the level and completeness of SCI. Individuals with higher spinal lesions have both restrictive and obstructive airway disease. Pharmacological approaches and expiratory muscle training are being studied as interventions to improve pulmonary function and cough strength with the objective of reducing pulmonary complications. Persons with spinal lesions above the 6th thoracic level lack both cardiac and peripheral vascular mechanisms to maintain blood pressure, and they are frequently hypotensive, with even worse hypotension with upright posture. Persistent and/or orthostatic hypotension may predispose those with SCI to cognitive impairments. The safety and efficacy of anti-hypotensive agents to normalize blood pressure in persons with higher level cord lesions is being investigated.

Comparison of coronary artery calcification scores and National Cholesterol Education program guidelines for coronary heart disease risk assessment and treatment paradigms in individuals with chronic traumatic spinal cord injury

OBJECTIVE

To investigate the risk of coronary heart disease (CHD) in individuals with spinal cord injury (SCI) according to the National Cholesterol Educational Program (NCEP) guidelines and CT coronary artery calcium scores (CCS).

RESEARCH

Cross-sectional study of consecutive sample of males with SCI presenting to a single site for CHD risk assessment.

PARTICIPANTS/METHODS

Males age 45-70 with traumatic SCI (American Spinal Injury Association (ASIA) A, B, and C) injured for at least 10 years with no prior history of clinical CHD. Medical history, blood-pressure, and fasting lipid panel were used to calculate risk for CHD with the use of the Framingham risk score (FRS). Risk and treatment eligibility status was assessed based on NCEP/FRS recommendations and by presence and amount of CCS. Percent agreement (PA) and kappa were calculated between the two algorithms. Spearman correlations were calculated between CCS and FRS and individual risk factors.

RESULTS

A total of 38 men were assessed; 18 (47.4%) had CCS > 0. The PA between NCEP/FRS assessment and CCS was 18% with a kappa of -0.03. 11 (28.9%) had CCS > 100 or >75th percentile for their age, sex, and race, which might qualify them for lipid-lowering treatment. Only 26 were placed into the same treatment category by NCEP/FRS and CCS, for a PA of 68% with a kappa of 0.35. In all, 20 (52.6%) were eligible for lipid-lowering treatment by either NCEP/FRS (n=9) or CCS (n = 11). Seven subjects were above the treatment threshold based on CCS, but not NCEP/FRS and five subjects were above the NCEP/FRS threshold, but not CCS. Just four subjects were eligible by both algorithms. CCS only correlated with FRS (r = 0.508, P = 0.001) and age (r = 0.679, P < 0.001).

Evidence for greater burden of peripheral arterial disease in lower extremity arteries of spinal cord-injured individuals

Spinal cord injury leads to increased risk for cardiovascular disease and results in greater risk of death. Subclinical markers of atherosclerosis have been reported in carotid arteries of spinal cord-injured individuals (SCI), but the development of lower extremity peripheral arterial disease (PAD) has not been investigated in this population. The purpose of this study was to determine the effect of spinal cord injury on ankle-brachial index (ABI) and intima-media thickness (IMT) of upper-body and lower-extremity arteries. We hypothesized that the aforementioned measures of lower-extremity PAD would be worsened in SCI compared with controls and that regular participation in endurance exercise would improve these in both groups. To test these hypotheses, ABI and IMT were determined in 105 SCI and compared with 156 able-bodied controls with groups further subdivided into physically active and sedentary. ABIs were significantly lower in SCI versus controls (0.96 ± 0.12 vs. 1.06 ± 0.07, P < 0.001), indicating a greater burden of lower-extremity PAD. Upper-body IMTs were similar for brachial and carotid arteries in controls versus SCI. Lower extremity IMTs revealed similar thicknesses for both superficial femoral and popliteal arteries, but when normalized for artery diameter, individuals with SCI had greater IMT than controls in the superficial femoral (0.094 ± 0.03 vs. 0.073 ± 0.02 mm/mm lumen diameter, P < 0.01) and popliteal (0.117 ± 0.04 vs. 0.091 ± 0.02 mm/mm lumen diameter, P < 0.01) arteries. The ABI and normalized IMT of SCI compared with controls indicate that subclinical measures of lower-extremity PAD are worsened in individuals with SCI. These findings should prompt physicians to consider using the ABI as a screening method to detect lower-extremity PAD in SCI.

An evidence-based review of aging of the body systems following spinal cord injury

STUDY DESIGN

Systematic review.

OBJECTIVE

To systematically review evidence on aging of the body systems after spinal cord injury (SCI).

SETTING

Toronto, Ontario and Vancouver, British Columbia, Canada.

METHODS

Electronic databases (MEDLINE/PubMed, CINAHL, EMBASE and PsycINFO), were searched for studies published between 1980 and 2009. The search was augmented by reviewing the reference lists of relevant papers. Non-intervention studies that were longitudinal or cross-sectional with able-bodied controls that were at minimum matched on chronological age were included for review. Levels of evidence were assigned to the study design using a modified Sackett scale.

RESULTS

Of the 74 studies selected for inclusion, 16 were longitudinal in design. The hypothesis that SCI represents a model for premature aging is supported by a large proportion of level 5 evidence for the cardiovascular and endocrine systems, level 2, 4 and 5 evidence for the musculoskeletal system, and limited level 5 evidence for the immune system. Only a few level 4 and 5 studies for the respiratory system were found. The evidence on the genitourinary system, gastrointestinal system, and for skin and subcutaneous tissues provide level 4 and 5 evidence that premature aging may not be occurring. The evidence on the nervous system does not provide evidence of premature aging as a result of SCI.

CONCLUSIONS

Premature aging appears to occur in some systems after SCI. Additional longitudinal studies are required to confirm these findings.

[Complications of chronic spinal cord injury]

BACKGROUND

A spinal cord injury changes body composition and metabolism over time. The main purpose of this article is to provide an overview of what is known about these changes and the consequences of those in the chronic phase, long after the acute injury.

MATERIAL AND METHODS

The article is based on own research and clinical experience, as well as a non-systematic search in the PubMed database.

RESULTS

The following has been documented for people with spinal cord injury: reduced bone and muscle mass, altered composition of muscle fibre, marked increase of body fat, decreased sensitivity to insulin and leptin and an increased activity in inflammatory signalling pathways. Changes are also demonstrated in hemostatic mechanisms and immune system.

INTERPRETATION

Changes in metabolism and hormonal regulation in people with spinal cord injury, may increase the risk of osteoporosis, obesity, cardiovascular disease and type 2 diabetes. Changed body composition and inflammatory activity may contribute to the higher incidence of cardiovascular disease and diabetes/metabolic syndrome, although other important risk factors (such as obesity and high blood pressure) may be absent. It has not been documented that changes in haemostatic mechanisms and the immune system are associated with the increased incidence of thromboembolic complications, severe infections or certain types of cancer.

Subclinical atherosclerosis is related to injury level but not to inflammatory parameters in spinal cord injury subjects

STUDY DESIGN

Cross-sectional.

OBJECTIVES

Individuals with spinal cord injury (SCI) exhibit increased carotid intima-media thickness (IMT) and are reported to be exposed to higher circulating levels of inflammatory mediators. This study evaluated the relationship between inflammatory markers and carotid surrogates of cardiovascular risk in subjects with SCI.

SETTING

São Paulo, Brazil.

METHODS

A total of 65 nondiabetic, nonhypertensive, sedentary, nonsmoker men (34 with SCI; 31 healthy subjects) were evaluated by medical history, anthropometry, routine laboratory tests, analysis of hemodynamic, inflammatory parameters and ultrasound examination of carotid arteries.

RESULTS

Subjects with SCI (18 tetraplegic and 16 paraplegic) had lower systolic blood pressure (P = 0.009), higher serum C-reactive protein (P = 0.001), tumor necrosis factor (TNF) receptor-II (P = 0.02) and TNF receptor-I (P = 0.04) levels and increased in vitro production of interleukin-6 by mononuclear cells (P = 0.04), compared to able-bodied individuals. No differences in serum interleukin-6, e-selectin, intercellular adhesion molecule-1, vascular cell adhesion molecule-1 and transforming growth factor-β levels, or in vitro release of interleukin-10, interleukin-17 and interferon-γ by mononuclear cells, were detected between the studied groups. Common carotid IMT, but not internal carotid resistive index, was significantly higher in subjects with SCI (P<0.0001 adjusted for C-reactive protein and TNF receptor-II levels). In addition, tetraplegic subjects exhibited increased IMT (P = 0.002 adjusted for systolic blood pressure and body mass index), but similar levels of inflammatory mediators compared to paraplegic ones.

CONCLUSIONS

Individuals with SCI exhibit a clustering of vascular and inflammatory surrogates of increased cardiovascular risk. Nevertheless, subclinical carotid atherosclerosis is related to injury level but not to increased inflammatory status in these subjects.

The potential metabolic consequences of cerebral palsy: inferences from the general population and persons with spinal cord injury

The metabolic consequences of cerebral palsy (CP) have not been reported. The observations and suggestions presented in this article are based on our current knowledge of physiology in the general population and on information on the known metabolic consequences of disability in persons with spinal cord injury. Because of pain, fatigue, and other secondary consequences of CP, adolescents with CP who are ambulatory may become less physically active with age. This phenomenon would be expected to be associated with deconditioning and adverse changes in body composition including atrophy of muscles and an absolute or relative increase in adiposity. Insulin resistance, hyperinsulinemia, and associated adverse metabolic changes may develop. In an unfavorable metabolic milieu, the ability of the pancreas to compensate for mild elevations of circulating glucose may diminish. The combination of reduced fitness and conventional risk factors for cardiovascular disease would be expected to increase the risk for coronary heart disease (CHD); however, there has been no assessment of the risk factors for CHD in adults with CP. Once subgroups with modifiable risk factors for cardiovascular disease have been identified, risk factors for CHD should be aggressively treated, according to current standards of care.

The relationships among serum glucose, albumin concentrations and carotid atherosclerosis in men with spinal cord injury

Limited information is available that examines the interrelationships between glucose tolerance, serum albumin, subclinical inflammation, and carotid atherosclerosis (CA) in patients with spinal cord injury (SCI). We prospectively recruited 110 male patients with traumatic SCI, 57 with SCI at thoracic level 6 or above (SCI-T6) and 53 with SCI at T7 or below (SCI-T7), and 62 age-matched able-bodied controls from the National Taiwan University Hospital. The associations among glucose levels after oral glucose tolerance tests (OGTT), serum albumin, high-sensitivity C-reactive protein (hs-CRP), and CA in terms of the extracranial carotid artery (ECCA) plaque score and common carotid artery (CCA) intima-media thickness (IMT) were examined. Results showed significantly higher post-challenge glucose levels and carotid plaque scores and lower serum albumin in the SCI-T6 patients. In addition, serum albumin was negatively associated with CA and post-challenge glucose levels. The higher post-challenge glucose levels at 120min (Glu120) were associated with higher serum hs-CRP levels and lower serum albumin levels. In addition, lower serum albumin levels were associated with a thicker CCA IMT and a higher prevalence of ECCA plaque. Mixed models revealed that body mass index, age, LDL-cholesterol, Glu120, homeostasis model assessment for insulin resistance (HOMA-IR), lower serum albumin and smoking habits were positively associated with CCA IMT. Age, HOMA-IR, LDL-cholesterol, and lower serum albumin were identified as the important factors for the presence of carotid plaque by multiple linear regression analyses. In conclusion, post-challenge hyperglycemia and serum albumin levels are important indicators of CV health in men with SCI.

Pulse wave velocity for assessment of arterial stiffness among people with spinal cord injury: a pilot study

BACKGROUND/OBJECTIVE

The most significant complication and leading cause of death for people with spinal cord injury (SCI) is coronary artery disease (CAD). It has been confirmed that aortic pulse wave velocity (PWV) is an emerging CAD predictor among able-bodied individuals. No prior study has described PWV values among people with SCI. The objective of this study was to compare aortic (the common carotid to femoral artery) PWV, arm (the brachial to radial artery) PWV, and leg (the femoral to posterior tibial artery) PWV in people with SCI (SCI group) to able-bodied controls (non-SCI group).

METHODS

Participants included 12 men with SCI and 9 non-SCI controls matched for age, sex, height, and weight. Participants with a history of CAD or current metabolic syndrome were excluded. Aortic, arm, and leg PWV was measured using the echo Doppler method.

RESULTS

Aortic PWV (mean +/- SD) in the SCI group (1,274 +/- 369 cm/s) was significantly higher (P < 0.05) than in the non-SCI group (948 +/- 110 cm/s). There were no significant between-group differences in mean arm PWV (SCI: 1,152 +/- 193 cm/s, non-SCI: 1,237 +/- 193 cm/s) or mean leg PWV (SCI: 1,096 +/- 173 cm/s, non-SCI: 994 +/- 178 cm/s) values.

CONCLUSIONS

Aortic PWV was higher among the SCI group compared with the non-SCI group. The higher mean aortic PWV values among the SCI group compared with the non-SCI group indicated a higher risk of CAD among people with SCI in the absence of metabolic syndrome.

Coronary heart disease in individuals with spinal cord injury: assessment of risk factors

STUDY DESIGN

Discussion document.

OBJECTIVES/METHOD

To review the work performed on conditions and disorders that predispose persons with spinal cord injury (SCI) to an increased risk of coronary heart disease (CHD).

RESULTS/DISCUSSION

Individuals with SCI have an increased prevalence of abnormalities in carbohydrate and lipid metabolism because of immobilization, muscle atrophy and relative adiposity. In those with SCI, an inverse relationship has been reported between serum high-density lipoprotein (HDL) cholesterol values and abdominal circumference, and a direct relationship between serum triglycerides levels and abdominal circumference. Persons with SCI have lower serum HDL cholesterol levels than able-bodied controls. A higher prevalence of insulin resistance and diabetes mellitus, as well as an earlier occurrence of coronary heart disease (CHD), has been reported in persons with SCI than in the general population. Recently, a higher prevalence and greater degree of coronary artery calcification by electron beam computerized tomography has been demonstrated in persons with SCI, even if matched with the able-bodied population for age, gender, ethnicity and conventional risk factors for CHD. Knowledge of relative risk of CHD in persons with SCI is important for appropriate intervention strategies. The conventional risk factors for CHD were determined in veterans with SCI to assign risk to determine target low-density lipoprotein cholesterol levels for therapeutic intervention. Limitations of conventional guidelines when applied to the SCI population should be appreciated. Conventional risk factors for CHD should be identified and treated in individuals with SCI, according to current standards of care.