Self-management program improves participation in patients with neuromuscular disease: A randomized controlled trial

OBJECTIVE

To investigate the effectiveness of Energetic, a self-management group program combining aerobic training, energy conservation management, and relapse prevention to improve social participation in patients with neuromuscular disease (NMD) and chronic fatigue.

METHODS

In this multicenter, assessor-blinded, 2-armed randomized controlled trial with repeated measurements, 53 patients with various types of NMD and chronic fatigue were randomly allocated to Energetic, a 4-month group intervention, or to usual care. The primary endpoint was social participation assessed with the Canadian Occupational Performance Measure (COPM) performance scale immediately postintervention. Secondary outcomes included COPM satisfaction scale, 6-Minute Walk Test (6MWT), and Checklist Individual Strength-subscale fatigue. Participants were followed for 11 months postintervention. Data were analyzed with linear models that account for repeated measurements.

RESULTS

Directly after intervention, the mean group difference for COPM-performance was 1.7 (95% confidence interval [CI] 1.0-2.4; p < 0.0001) in favor of the intervention group (n = 29), adjusted for baseline, sex, diagnosis, and work status. This effect was retained at 11 months follow-up (0.9; 95% CI 0.0-1.7; p = 0.049). The COPM satisfaction scale and 6MWT improved more in the intervention group compared to usual care. After 3 and 11 months follow-up, most beneficial effects on social participation and functional endurance were retained.

CONCLUSION

Energetic led to sustainable improvements in social participation and functional endurance compared to usual care in patients with NMD and chronic fatigue.Clinicaltrials.gov IDENTIFIER: NCT02208687.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that a combination of aerobic training, energy conservation management, and relapse prevention improves social participation in patients with NMD and chronic fatigue.

Validity and reliability of serratus anterior hand held dynamometry

BACKGROUND

Strength testing of the serratus anterior muscle with hand held dynamometry (HDD) in supine subjects has low reproducibility, and is influenced by compensatory activity of other muscles like the pectoralis major and upper trapezius. Previously, two manual maximum voluntary isometric contraction tests of the serratus anterior muscle were reported that recruited optimal surface electromyography (sEMG) activity in a sitting position. We adapted three manual muscle tests to make them suitable for HHD and investigated their validity and reliability.

METHODS

Twenty-one healthy adults were examined by two assessors in one supine and two seated positions. Each test was repeated twice. Construct validity was determined by evaluating force production (assessed with HHD) in relation to sEMG of the serratus anterior, upper trapezius and pectoralis major muscles, comparing the three test positions. Intra- and interrater reliability were determined by calculating intra-class correlation coefficients (ICC) smallest detectable change (SDC) and standard error of measurement (SEM).

RESULTS

Serratus anterior muscle sEMG activity was most isolated in a seated position with the humerus in 90° anteflexion in the scapular plane. This resulted in the lowest measured force levels in this position with a mean force of 296 N (SEM 15.8 N). Intrarater reliability yielded an ICC of 0.658 (95% CI 0.325; 0.846) and an interrater reliability of 0.277 (95% CI -0.089;0.605). SDC was 127 Newton, SEM 45.8 Newton.

CONCLUSION

The results indicate that validity for strength testing of the serratus anterior muscle is optimal with subjects in a seated position and the shoulder flexed at 90° in the scapular plane. Intrarater reliability is moderate and interrater reliability of this procedure is poor. However the high SDC values make it difficult to use the measurement in repeated measurements.

NA-CONTROL: a study protocol for a randomised controlled trial to compare specific outpatient rehabilitation that targets cerebral mechanisms through relearning motor control and uses self-management strategies to improve functional capability of the upper extremity, to usual care in patients with neuralgic amyotrophy

Background

Neuralgic amyotrophy (NA) is a distinct peripheral neurological disorder of the brachial plexus with a yearly incidence of 1/1000, which is characterised by acute severe upper extremity pain. Weakness of the stabilising shoulder muscles in the acute phase leads to compensatory strategies and abnormal motor control of the shoulder - scapular dyskinesia. Despite peripheral nerve recovery, scapular dyskinesia often persists, leading to debilitating residual complaints including pain and fatigue. Evidence suggests that persistent scapular dyskinesia in NA may result from maladaptive cerebral neuroplasticity, altering motor planning. Currently there is no proven effective causative treatment for the residual symptoms in NA. Moreover, the role of cerebral mechanisms in persistent scapular dyskinesia remains unclear.

Methods

NA-CONTROL is a single-centre, randomised controlled trial comparing specific rehabilitation to usual care in NA. The rehabilitation programme combines relearning of motor control, targeting cerebral mechanisms, with self-management strategies. Fifty patients will be included. Patients are recruited through the Radboud university medical center Nijmegen, the Netherlands. Patients with a (suspected) diagnosis of NA, with lateralized symptoms and scapular dyskinesia in the right upper extremity, who are 18 years or older and not in the acute phase can be included. The primary outcome is the Shoulder Rating Questionnaire score, which measures functional capability of the upper extremity. Secondary clinical outcomes include measures of pain, fatigue, participation, reachable workspace, muscle strength and quality of life. In addition, motor planning is assessed with first-person motor imagery and functional magnetic resonance imaging. In a sub-study the patients are compared to 25 healthy participants, to determine the involvement of cerebral mechanisms. This will enable interpretation of cerebral changes associated with the rehabilitation programme and functional impairments in NA.

Discussion

NA-CONTROL is the first randomised trial to investigate the effect of specific rehabilitation on residual complaints in NA. It also is the first study into the cerebral mechanisms that might underlie persistent scapular dyskinesia in NA. It thus may aid the further development of mechanism-based interventions for disturbed motor control in NA and in other peripheral neurological disorders.

Trial registration

ClinicalTrials.gov, NCT03441347. Registered on 20 February 2018.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3556-4) contains supplementary material, which is available to authorized users.

Aerobic Exercise Therapy in Ambulatory Patients With ALS: A Randomized Controlled Trial

Background: Weakness caused by motor neuron degeneration in amyotrophic lateral sclerosis (ALS) may result in avoidance of physical activity, resulting in deconditioning and reduced health-related quality of life (HRQoL). Objective: To study the effectiveness of aerobic exercise therapy (AET) on disease-specific and generic HRQoL in ambulatory patients with ALS. Methods: We conducted a multicenter, assessor-blinded, randomized controlled trial. Using a biphasic randomization model, ambulatory ALS patients were assigned (1:1) to AET+usual care (UC), or UC. AET consisted of a 16-week aerobic cycling exercise program. Primary outcome measures were the 40-item ALS assessment questionnaire (ALSAQ-40), and the mental component summary (MCS) and physical component summary (PCS) scores of the short-form survey (SF-36), using linear mixed effects models. Per-protocol (PP) analysis was performed for those patients who attended ≥75% of the training sessions; controls were matched (1:1) by propensity score matching. Results: Of 325 screened patients, 57 were randomized: 27 to AET+UC and 30 to UC. No significant mean slope differences between groups were observed for ALSAQ-40 (-1.07; 95% confidence interval [CI] -2.6 to 0.5, P=0.172) nor for SF-36 MCS (0.24; -0.7 to 1.1, P=0.576) or PCS (-0.51; -1.4 to 0.38, P=0.263). There were no adverse events related to the AET. PP-analyses showed significantly less deterioration in ALSAQ-40 (-1.88, -3.8 to 0.0, P=0.046) in AET+UC compared to UC. Conclusions: AET+UC was not superior to UC alone in preserving HRQoL in ambulatory ALS patient. However, the study was unfortunately underpowered, because only 10 patients completed the protocol. AET+UC may preserve disease-specific HRQoL in slow progressors. Clinical trial registration number: Netherlands National Trial Register (NTR): 1616.

Meet and eat, an interdisciplinary group intervention for patients with myotonic dystrophy about healthy nutrition, meal preparation, and consumption: a feasibility study

Purpose: To develop and evaluate an interdisciplinary group intervention for patients with myotonic dystrophy regarding healthy nutrition, meal preparation, and consumption, called Meet and Eat.Materials and methods: A design-based approach was used, exploring experiences and needs of patients with myotonic dystrophy and their next of kin. This resulted in a 4-week interdisciplinary outpatient group intervention to increase awareness and change behavior. In a mixed-method feasibility study this intervention was evaluated with participants and facilitators.Results: Participants reported on social impact of difficulties with eating and drinking (speaking, swallowing, and social embarrassment) and a variety of complaints affecting meal preparation and consumption. Patients and family members expressed the wish to learn from others. After delivery of the intervention, self-reported outcome measures demonstrated improvement on eating and drinking issues in daily life. The qualitative evaluation showed increased awareness and appreciation of the following design principles: peer support, multidisciplinary approach, active involvement of patient with myotonic dystrophy and their next of kin by using personal goals and motivational interviewing.Conclusion: Participation in Meet and Eat seemed to increase insight in patients' condition and ways of management. However, a longer self-management life style program is recommended to change behavior.Implications for rehabilitationPatients with myotonic dystrophy experience physical, cognitive and psychosocial problems to manage healthy nutrition, meal preparation, and consumption;This multidisciplinary group intervention Meet and Eat in patients with myotonic dystrophy appears to be feasible and seems to result in increased insight and management strategies;Peer support, multidisciplinary approach, personal goals, and involvement of family were key factors;To change eating and drinking behavior, a 4-week intervention is too short.

Respiratory Assessment of ALS Patients: A Nationwide Survey of Current Dutch Practice

BACKGROUND AND OBJECTIVE

Non-invasive ventilation (NIV) is an established treatment for respiratory failure in patients with amyotrophic lateral sclerosis (ALS). Several studies have shown room for improvement with regard to respiratory care for ALS patients, including latency of referral. These studies focused on the time period starting at the moment of referral to a home ventilation service (HVS) onwards. In the current study we performed a nationwide survey to gain insight in the trajectory before referral. We questioned the assessment of respiratory impairment by ALS physicians/care teams, including criteria for referral to an HVS.

METHODS

We requested 40 ALS care teams in the Netherlands to fill in an online questionnaire on respiratory management in ALS patients.

RESULTS

Thirty-two ALS care teams (80%) responded. Forced vital capacity was the most frequently used test at each outpatient visit (72%) and often served as a criterion (78%) for referral to an HVS. Other respiratory function measurements that were performed less often included peak cough flow (50%), maximum inspiratory/expiratory pressure (31% /28%) and sniff nasal inspiratory pressure (13%). Morning headache was the most frequently questioned complaint (94%), followed by daytime sleepiness (91%). Dyspnoea and orthopnoea were reported by 38% and 59% as important complaints. Out of all patients under the care of the ALS care teams, the mean estimated proportion of patients that was referred to an HVS was 69% (range 20-100%). When physicians refrained from referral, the most often cited reasons were patient's decision to withhold NIV (94%) and cognitive impairment (50%). Sixteen percent of the respondents stated bulbar impairment as a reason to refrain from referral.

CONCLUSION

Despite findings in previous studies on the superiority of SNIP and PCF as compared to FVC, our study shows that a majority of ALS care teams still prefers to use FVC for the assessment of respiratory dysfunction and for the timing of referral to an HVS. Another finding is that bulbar impairment is not an obstacle for referral for NIV.

Phrenic neuropathy and diaphragm dysfunction in neuralgic amyotrophy

OBJECTIVE

To describe the clinical phenotype and recovery of diaphragm dysfunction caused by neuralgic amyotrophy in a large cohort of patients, to improve accurate awareness of this entity, and to encourage adoption of a standardized approach for diagnosis and treatment.

METHODS

This observational cohort study recruited adult patients with neuralgic amyotrophy and symptoms of idiopathic phrenic neuropathy from the database of the Dutch expert center for neuralgic amyotrophy and the Dutch centers for home mechanical ventilation. Demographic and clinical information on diagnosis, symptoms, and recovery was obtained from chart review. We attempted to contact all patients for a follow-up interview.

RESULTS

Phrenic neuropathy occurs in 7.6% of patients with neuralgic amyotrophy. Unilateral diaphragmatic dysfunction and bilateral diaphragmatic dysfunction are frequently symptomatic, causing exertional dyspnea, orthopnea, disturbed sleep, and excessive fatigue. Diagnostic practices varied widely and were often not optimally targeted. The majority of patients experienced at least moderate recovery within 2 years.

CONCLUSION

We recommend screening every patient with neuralgic amyotrophy for diaphragm dysfunction by asking about orthopnea and by performing upright and supine vital capacity screening and diaphragm ultrasound in cases of suspected phrenic neuropathy to optimize diagnosis and care.

Reflections of patients and therapists on a multidisciplinary rehabilitation programme for persons with brachial plexus injuries

PURPOSE

There is lack of knowledge, evidence, and guidelines for rehabilitation interventions for persons with neuralgic amyotrophy (NA) or brachial plexus pathology. A first pilot study, evaluating the effect of an integrated rehabilitation programme, showed improvements in activity and participation levels.

AIM

To gain insight, from the perspective of patients and therapists, into the critical ingredients of the programme, that contributed to improvements in activity and participation.

MATERIALS AND METHODS

A qualitative study using semi-structured interviews with eight patients and five therapists (three occupational therapists and two physical therapists). Participants were asked to identify and describe factors regarding the rehabilitation that they perceived as positive and aspects of the programme that could be improved. Data were analysed using a constant comparative approach.

RESULTS

Patients reported (1) Time to diagnose: "Finally I'm in the right place;" (2) Awareness: "They gave me a mirror;" (3) Partnership: "There was real contact with the therapists; we made decisions together;" (4) Close collaboration: "Overlapping scopes of practice; doing the same from a different perspective;" and finally (5) Self-management: "Now I can do it myself." Therapists reported (1) "Patients knowledge and understanding is critical to success;" (2) "Activate problem solving and decision making;" (3) "Personalize your therapy; it's more than just giving exercises and information;" (4) "Constant consultation within the team; consistency in messages and approach;" and (5)" Ultimately the patient is in charge."

CONCLUSIONS

The critical ingredients, correspond well with each other and include a person-centred approach, education, support in problem solving and decision making and an integrated team approach. These ingredients provided the patients with confidence to take responsibility to manage their everyday lives, the ultimate goal of the programme. Implications for rehabilitation Both patients and therapists believe that the ability to self-manage and take control should be the outcome of high quality integrated rehabilitation programmes for patients with neuralgic amyotrophy and/or other brachial plexus injuries. A person-centred, collaborative, and integrated team approach, among all members of the team, are critical components of care delivery in personalised interventions. Critical programme ingredients are knowledge and education of both the patient and therapists; partnership between patient-therapist and within the team; patient activation and self-reflection; and personalised care. Patients recommend more options for personalisation of the intensity and duration of rehabilitation, the possibility to consult a psychologist and peer support within a group setting.

The predictive value of respiratory function tests for non-invasive ventilation in amyotrophic lateral sclerosis

Background

Non-invasive ventilation (NIV) improves survival and quality of life in amyotrophic lateral sclerosis (ALS) patients. The timing of referral to a home ventilation service (HVS), which is in part based on respiratory function tests, has shown room for improvement. It is currently unknown which respiratory function test predicts an appropriate timing of the initiation of NIV.

Methods

We analysed, retrospectively, serial data of five respiratory function tests: forced vital capacity (FVC), peak cough flow (PCF), maximum inspiratory and expiratory pressure (MIP and MEP) and sniff nasal inspiratory pressure (SNIP) in patients with ALS. Patients who had had at least one assessment of respiratory function and one visit at the HVS, were included. Our aim was to detect the test with the highest predictive value for the need for elective NIV in the following 3 months. We analysed time curves, currently used cut-off values for referral, and respiratory function test results between ‘NIV indication’ and ‘no-NIV indication’ patients.

Results

One hundred ten patients with ALS were included of whom 87 received an NIV indication; 11.5% had one assessment before receiving an NIV indication, 88.5% had two or more assessments. The NIV indication was based on complaints of hypoventilation and/or proven (nocturnal) hypercapnia. The five respiratory function tests showed a descending trend during disease progression, where SNIP showed the greatest decline within the latest 3 months before NIV indication (mean = −22%). PCF at the time of referral to the HVS significantly discriminated between the groups ‘NIV-indication’ and ‘no NIV-indication yet’ patients at the first HVS visit: 259 (±92) vs. 348 (±137) L/min, p = 0.019. PCF and SNIP showed the best predictive characteristics in terms of sensitivity.

Conclusion

SNIP showed the greatest decline prior to NIV indication and PCF significantly differentiated ‘NIV-indication’ from ‘no NIV-indication yet’ patients with ALS. Currently used cut-off values might be adjusted and other respiratory function tests such as SNIP and PCF may become part of routine care in patients with ALS in order to avoid non-timely initiation of (non-invasive) ventilation.

Quantification of gait in mitochondrial m.3243A > G patients: a validation study

Background

More than half of the patients harbouring the m.3243A > G mutation were found to have trouble maintaining balance when walking in a recent study by our group. Others demonstrated that these patients had an abnormal gait pattern, as quantified by gait analysis. Gait analysis is an emerging method to quantify subtle changes in walking pattern, also during therapeutic interventions. Therefore, we aimed to test the reliability and reproducibility of gait analysis and select the most suitable protocol for this group of patients using a GAITRite electronic walkway. Four different protocols were tested: normal walking, dual task, post exercise and after a ten minutes of rest.

Results

In total 36 patients with the m.3243A > G mutation and 50 healthy controls were enrolled in this study. Overall high intra class correlation coefficients were found in all experimental conditions for both patients and healthy controls indicating good reproducibility. Marked differences in gait between patients and controls were observed and were in line with the only available exploratory study performed. There was a good correlation between both the overall NMDAS score, NMDAS subscale scores, both markers for disease severity, and specific gait parameters.

Conclusions

The observed reliability of the test makes GAITRite a suitable instrument for intervention studies in patients with mitochondrial disease.

The 6-min mastication test: a unique test to assess endurance of continuous chewing, normal values, reliability, reproducibility and usability in patients with mitochondrial disease

In patients with mitochondrial disease, fatigue and muscle problems are the most common complaints. They also experience these complaints during mastication. To measure endurance of continuous mastication in patients with mitochondrial diseases, the 6-min mastication test (6MMT) was developed. This study included the collection of normal data for the 6MMT in a healthy population (children and adults). During 6 min of continuous mastication on a chew tube chewing cycles per minute, total amount of chewing cycles and the difference between minute 1 (M₁ ) and minute 6 (M₂ ) were collected in 271 healthy participants (5-80 years old). These results were compared with those of nine paediatric and 25 adult patients with a mitochondrial disease. Visual analogue scale (VAS) scores were collected directly after the test and after 5 min. A qualitative rating was made on masticatory movements. The reproducibility of the 6MMT in the healthy population with an interval of approximately 2 weeks was good. The inter-rater reliability for the observations was excellent. The patient group demonstrated lower total amount of chewing cycles or had greater differences between M₁ and M₆ . The 6MMT is a reliable and objective test to assess endurance of continuous chewing. It demonstrates the ability of healthy children and adults to chew during 6 min with a highly stable frequency of mastication movements. The test may give an explanation for the masticatory problems in patient groups, who are complaining of pain and fatigue during mastication.

Neuralgic amyotrophy: An update on diagnosis, pathophysiology, and treatment

In this review we provide a current overview of the clinical features, pathophysiology, epidemiology, and diagnostic and therapeutic strategies in neuralgic amyotrophy (NA). The disorder has several phenotypic variations, with a classic form in 70% of the patients. It is not rare, with an incidence of 1 per 1,000 individuals, but it is still often missed. Recurrences are common, yet the proposed multifactorial etiology, which includes genetic, biomechanical, and immunologic factors, limits our capacity to predict or prevent them. NA is a clinical diagnosis, and ancillary studies serve to exclude infectious or malignant causes or to assess a differential diagnosis. If patients are seen early and are still in pain, a short trial of high-dose oral corticosteroids is advised, and adequate analgesia may require opioids and non-steroidal anti-inflammatory drugs. Persistent complaints are common, and a multidisciplinary rehabilitation approach focusing on scapular coordination, energy distribution strategies, and self-management is indicated.

Effectiveness and cost-effectiveness of a self-management group program to improve social participation in patients with neuromuscular disease and chronic fatigue: protocol of the Energetic study

Background

Chronic fatigue is present in more than 60% of the patients with a neuromuscular disease and can be their most disabling symptom. In combination with other impairments, fatigue often results in low levels of physical activity and decreased social participation, leading to high societal costs. ‘Energetic’ is a self-management group program aimed at improving social participation, physical endurance and alleviating fatigue in these patients. The primary aim of this study is to evaluate the effectiveness and cost-effectiveness of the Energetic program.

Methods/Design

A multicentered, assessor-blinded, two-armed randomized controlled trial is conducted with evaluations at inclusion and four, seven and fifteen months later. The study includes patients with a neuromuscular disease and chronic fatigue and, when present, their caregivers. The participants are randomized (ratio 1:1) to either an intervention group, receiving the Energetic program, or a control group, receiving usual care (i.e., no specific intervention). The Energetic program covers four months and includes four modules: 1) individually tailored aerobic exercise training; 2) education about aerobic exercise; 3) self-management training in applying energy conservation strategies; and 4) implementation and relapse prevention in daily life. Two months after cessation of the program a booster session is provided. The primary outcome is the perceived performance score of the Canadian Occupational Performance Measure (COPM). Secondary outcomes include the COPM-satisfaction score, and measures of fatigue, physical endurance, activity engagement, mood, and self-efficacy. Caregiver burden is also evaluated as a secondary outcome. Health-related quality of life and medical and societal costs are assessed to estimate cost-effectiveness of the program.

Discussion

The Energetic study is the first randomized controlled trial to evaluate the effectiveness and cost-effectiveness of a combined physical and self-management group training program for improving social participation, physical endurance and alleviating fatigue in patients with neuromuscular diseases. It will generate new insights in (cost-)effective rehabilitation strategies for these incurable conditions.

Trial registration

Clinicaltrials.gov NCT02208687.

[Incidence of neuralgic amyotrophy in a primary care setting: a prospective cohort study]

OBJECTIVE

To assess the incidence of classic neuralgic amyotrophy (NA) in a primary care setting.

DESIGN

Prospective cohort study.

METHOD

During the year 2012 we registered all new cases of neck, shoulder or arm symptoms from two large primary care centres serving a population of 14,118. Prior to commencing the study, general practitioners attended a short training session on how to diagnose classic NA. After inclusion, patients in whom general practitioners suspected NA were offered a neurologic assessment for diagnostic confirmation.

RESULTS

Of the 492 patients identified with new onset of neck, shoulder or arm symptoms, 34 were suspected of having NA. Neurologic evaluation confirmed the diagnosis in 14 patients. For the Netherlands, this translates to an incidence of 1 in 1,000.

CONCLUSION

Our findings suggest that NA is 30-50 times more common than previously thought; in the Netherlands, this would mean 17,000 instead of 500 new cases each year. Lack of awareness of the disorder and its clinical presentation seems the most likely explanation for this difference. Since NA may lead to sustained symptoms and functional limitations in the chronic phase, increased attention is urgently required to improve diagnostics and treatment.

Efficacy of a combined physical and occupational therapy intervention in patients with subacute neuralgic amyotrophy: a pilot study

BACKGROUND

Neuralgic Amyotrophy (NA) is characterized by neuropathic pain, subsequent patchy paresis and possible sensory loss in the upper extremity. Many patients experience difficulties in performing activities of daily life and are unable to resume work. We developed a combined physical- and occupational therapy program for patients recovering from NA.

OBJECTIVE

Evaluation of the effectiveness of a multidisciplinary intervention program for patients with subacute NA.

METHODS

We performed a within subject proof-of-principle pilot study in eight patients with subacute NA. Patients followed 8 hours of physical and 8 hours of occupational therapy spread over a 16-week period.

PRIMARY OUTCOME MEASURES

The Canadian Occupational Performance Measure (COPM) and Shoulder Rating Questionnaire (SRQ).

SECONDARY OUTCOME MEASURE

Disability of Arm Shoulder and Hand (DASH).

RESULTS

Improvements (mean (95% CI)) were found in the performance and satisfaction scores of the COPM +2.3 (0.9-3.7) and +1.4 (0.4-2.4) points, respectively and the SRQ +14.8 (7.4-22.0) points. The majority of patients (6 out of 8) also demonstrated improvements in the DASH.

CONCLUSION

The proposed physical and occupational therapy program, may be effective for patients with subacute NA, as demonstrated by improvements in activity, performance and participation.

Complete absence of evening melatonin increase in tetraplegics

Individuals with a spinal cord injury (SCI), especially with tetraplegia, experience poor sleep quality, and this may be related to impaired control of circadian rhythmicity. Here, we examined the evening onset of melatonin secretion, an important hormone for the initiation of sleep, in people with a complete cervical (tetraplegia) and thoracic (paraplegia) SCI, and age- and sex-matched able-bodied control participants. Multiple samples of salivary melatonin were obtained during the evening hours and analyzed by ELISA methods in 10 control partcipants, 9 individuals with paraplegia, and 6 individuals with tetraplegia. Sleep quality was assessed using questionnaires. Interactive effects of group and time were found for melatonin levels (P=0.022). In the control and paraplegia groups, the mean melatonin level increased significantly from 2.59 ± 1.04 and 4.28 ± 3.28 pg/ml at 7 PM to 10.62 ± 4.59 and 13.10 ± 7.39 pg/ml at 11 PM, respectively (P<0.001). In the tetraplegia group, melatonin level was 5.25 ± 3.72 at 7 PM but only 2.41 ± 1.25 pg/ml at 11 PM (P>0.05). Decreased sleep quality was more prevalent in individuals with tetraplegia (83%) and paraplegia (75%) compared with controls (20%; P=0.02). Unlike in the control and paraplegia groups, the evening increase in melatonin concentration was completely absent in the tetraplegia group. This provides biological insight into sleep regulation in humans and provides better understanding of the poor sleep quality in people with tetraplegia.

Leg vasoconstriction during head-up tilt in patients with autonomic failure is not abolished

Maintaining blood pressure during orthostatic challenges is primarily achieved by baroreceptor-mediated activation of the sympathetic nervous system, which can be divided into preganglionic and postganglionic parts. Despite their preganglionic autonomic failure, spinal cord-injured individuals demonstrate a preserved peripheral vasoconstriction during orthostatic challenges. Whether this also applies to patients with postganglionic autonomic failure is unknown. Therefore, we assessed leg vasoconstriction during 60° head-up tilt in five patients with pure autonomic failure (PAF) and two patients with autonomic failure due to dopamine-β-hydroxylase (DBH) deficiency. Ten healthy subjects served as controls. Leg blood flow was measured using duplex ultrasound in the right superficial femoral artery. Leg vascular resistance was calculated as the arterial-venous pressure gradient divided by blood flow. DBH-deficient patients were tested off and on the norepinephrine pro-drug l-threo-dihydroxyphenylserine (l-DOPS). During 60° head-up tilt, leg vascular resistance increased significantly in PAF patients [0.40 ± 0.38 (+30%) mmHg·ml−1·min−1]. The increase in leg vascular resistance was not significantly different from controls [0.88 ± 1.04 (+72%) mmHg·ml−1·min−1]. In DBH-deficient patients, leg vascular resistance increased by 0.49 ± 0.01 (+153%) and 1.52 ± 1.47 (+234%) mmHg·ml−1·min−1 off and on l-DOPS, respectively. Despite the increase in leg vascular resistance, orthostatic hypotension was present in PAF and DBH-deficient patients. Our results demonstrate that leg vasoconstriction during orthostatic challenges in patients with PAF or DBH deficiency is not abolished. This indicates that the sympathetic nervous system is not the sole or pivotal mechanism inducing leg vasoconstriction during orthostatic challenges. Additional vasoconstrictor mechanisms may compensate for the loss in sympathetic nervous system control.

Effect of different sympathetic stimuli-autonomic dysreflexia and head-up tilt-on leg vascular resistance in spinal cord injury

OBJECTIVE

To compare the effect of different sympathetic stimuli, that is, exaggerated sympathetic activity and orthostatic challenges, on the increase in leg vascular resistance in persons with spinal cord injury (SCI) without and controls with supraspinal sympathetic control.

DESIGN

Case-control intervention study.

SETTING

Physiology research laboratory.

PARTICIPANTS

Persons with SCI (N=9; motor and sensory complete spinal cord lesion above the sixth thoracic spinal segment) and able-bodied controls (N=9).

INTERVENTIONS

In persons with SCI, exaggerated sympathetic activity was evoked by autonomic dysreflexia, and in controls, by using a cold pressor test (CPT). A 30° head-up tilt (HUT) was performed in both groups.

MAIN OUTCOME MEASURE

Leg blood flow was measured by using venous occlusion plethysmography during the different sympathetic stimuli. Leg vascular resistance was calculated as the arterial-venous pressure gradient divided by blood flow.

RESULTS

In persons with SCI, leg vascular resistance significantly increased during autonomic dysreflexia and 30° HUT (25±20 and 24±13 arbitrary units [AU], respectively), with no difference (P=.87) between stimuli. In controls, leg vascular resistance significantly increased during CPT and 30° HUT (15±13 and 29±12AU, respectively) with no difference (P=.03) between stimuli. There were no differences (P=.22) in increase in leg vascular resistance during the different sympathetic stimuli between persons with SCI and controls.

CONCLUSIONS

The increase in leg vascular resistance during autonomic dysreflexia in persons with SCI is not different from that during 30° HUT, which might be caused by a limited vasoconstrictor reserve. Despite the lack of supraspinal sympathetic control in persons with SCI, the increase in leg vascular resistance during exaggerated sympathetic activity was not different from controls.