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Functional disturbances of the autonomic nerve in nasal hyperreactivity: an up-date review.

During the 1980s, our view of airway hypersensitivity was altered significantly. Advances in biochemical techniques revealed involvement of several nonspecific events in nasal hyperreactivity: Autonomic dysfunction involving primary and/or secondary receptor disorders, epithelial damage by cytotoxic proteins in eosinophil, which is stimulated by inflammatory mediators, and an axonal reflex of sensory C fibers. Since 1983, we have neurobiochemically investigated the autonomic nerve dysfunction in the nasal mucosa of patients with nasal allergy and guinea pigs with experimentally-induced nasal hypersensitivity. We propose the following mechanisms as potential contributors to the disturbance of the beta receptor function in airway hyperreactivity: i) Down-regulation caused by excess endogenous norepinephrine stimulation, ii) down-regulation and uncoupling to adenylate cyclase, produced by the inflammatory mediator-induced activation of protein kinase C, iii) the action of beta receptor inhibitory factor, presumably anti beta receptor autoantibodies, and iv) dysfunction of beta receptor kinase, which is known to cause short-term desensitization of beta receptors after exposure to beta agonists. This review provides the anatomical and neurobiochemical background for the autonomic regulation and dysfunction in the nose. We also introduce our series of experiments and the above updated hypotheses of how functional disturbances of the autonomic nerve in the nasal mucosa may occur.

Autonomic Nervous System↗

Autonomic nervous system involvement in Behçet's disease.

In this study, R-R interval variation (RRIV) and sympathetic skin response (SSR) were used to evaluate autonomic nervous system (ANS) involvement in 25 patients with Behçet's disease. Normative values of RRIV and SSR were determined in a group of 25 healthy volunteers. R-R interval variation at rest (R%) and during deep breathing (D%), the difference between D% and R% (D-R), and the ratio of D% to R% (D/R) were determined. R-R interval variations did not show a significant difference between patients and the control group. There was a negative correlation with age for R%, D%, and D-R in the control group, but none was found in the patient group. The SSR latencies were two standard deviations above the normal mean values in three patients who described symptoms of autonomic dysfunction. In conclusion, symptoms of autonomic disturbance must be evaluated carefully for a possible involvement of ANS that might occur in Behçet's disease.

Adolescent↗

Antibody in the CSF of patients with multiple system atrophy reacts specifically with rat locus ceruleus.

Idiopathic chronic autonomic dysfunction may occur as pure autonomic failure (PAF) or in association with multiple system atrophy (MSA). CSF immunoreactivity to rat locus ceruleus occurred in a significantly greater number of samples from MSA patients compared to control subjects or patients with PAF. Other brain regions infrequently showed immunoreactivity. These findings suggest that degeneration in MSA may release antigen(s) that induce antibodies against locus ceruleus neurons. Further studies are required to determine whether immune abnormalities play a pathogenetic role in MSA. Lack of CSF immunoreactivity in PAF is consistent with primarily peripheral involvement.

Adult↗

Discordant mental and physical efforts in an autistic patient.

We investigated whether there was mental effort in response to verbal commands in a 16-year old girl with autism, a high degree of non-compliance with commands and symptoms of autonomic dysfunction by monitoring the brainstem autonomic tone during an attempt to perform isometric exercise. An index of cardiac vagal tone (CVT), cardiac sensitivity to baroreflex (CSB), heart rate (HR) and mean arterial blood pressure (MAP) were measured simultaneously. Physical non-compliance with our commands meant there was no force applied by the patient during the attempted exercise, but CVT and CSB were both reduced and sustained at very low levels throughout the attempt, while MAP and HR were increased concurrently to higher levels in the same period. This vagal withdrawal to allow concurrent increases in HR and MAP is an arousal response appropriate for isometric exercise, which is a sign of a positive mental effort to comply with our commands. These results demonstrate discordant mental and physical efforts in our patient. In this particular case, the physical inabilities in some instances could have been mislabelled as mental non-compliance due to autism. It would be worthwhile to investigate the prevalence of discordant mental and physical efforts in autism.

Adolescent↗

Assessment of cardiovascular autonomic function in myotonic dystrophy type 2 (DM2/PROMM).

BACKGROUND: Proximal myotonic myopathy is an autosomal dominant multisystem disorder with a recently defined CCTG expansion on chromosome 3 in the major subgroup (myotonic dystrophy type 2). Cardiac rhythm disturbances have been described in patients with this disease, but it is not known whether myotonic dystrophy type 2/proximal myotonic myopathy patients suffer from dysautonomia and whether cardiac arrhythmias relate to autonomic dysfunction. OBJECTIVES: To investigate cardiovascular autonomic function in myotonic dystrophy type 2/proximal myotonic myopathy patients with and without cardiac arrhythmias. PATIENTS AND METHODS: Standard autonomic function tests (heart rate responses to Valsalva manoeuvre, deep breathing and active change of posture, and blood pressure responses to active change of posture and sustained handgrip), resting heart rate variability in the time- and frequency-domain, and the corrected QT interval length were determined in 16 patients with genetically defined myotonic dystrophy type 2/proximal myotonic myopathy and compared to the results obtained in 16 age- and sex-matched healthy control subjects. RESULTS: Standard autonomic tests yielded similar results in both groups. Measures of heart rate variability tended to be lower in myotonic dystrophy type 2/proximal myotonic myopathy patients compared to healthy controls, but reached statistical significance only for the number of R-R intervals exceeding 50 ms (p50) and the power spectrum density in the low-frequency range (low-frequency power). Four patients (25%) suffered from mild cardiac rhythm disturbances encompassing paroxysmal tachycardia, sinoatrial block, right bundle branch block, ventricular premature beats and bradycardia. The autonomic responses of these patients were essentially similar compared to those without cardiac arrhythmias, apart from a decreased heart rate response to deep breathing in the patients with cardiac arrhythmias. CONCLUSIONS: We found no major abnormalities of cardiovascular autonomic function in patients with myotonic dystrophy type 2/proximal myotonic myopathy, neither in the whole study group nor in the subgroup of patients with cardiac rhythm abnormalities.

Adult↗

Sympathetic skin response asymmetry in early stage idiopathic Parkinson's disease.

Simultaneous bilateral plantar sympathetic skin response (SSR) was studied in 25 patients with early stage idiopathic Parkinson's disease (IPD), characterized by monolateral motor involvement (Hoehn and Yahr, stage <2) and without clinical evidence of autonomic dysfunctions. Thirteen (mean age: 68.69 +/- 7.70, range 55-76) had extrapyramidal clinical signs only at the left body side, 12 (mean age 66.60 +/- 7.43, range 51-73) at the right body side. A group of 25 healthy, age-matched, subjects were also evaluated. To evoke the responses, trains of 10 electrical pulses were applied at different intensities and frequencies. Only intensities of stimulation > or = 5 times the sensory electrical threshold always assured bilateral plantar responses in all the examined subjects. Amplitude asymmetry between left and right responses was found only in the IPD patients (P < 0.05). The amplitude reduction corresponded to the motor affected side. No analogue latency variation was observed in any group. Independently from the peripheral or central origins of such phenomena, these findings suggest that simultaneous bilateral SSR amplitude evaluation could be useful, in early IPD patients, to demonstrate and to monitor the sympathetic cholinergic dysfunction, despite the lack of autonomic symptoms.

Aged↗

Autonomic regulation of cardiopulmonary functions in sleep apnea syndrome and narcolepsy.

Thirteen patients with sleep apnea syndrome, nine with narcolepsy, and age-matched controls were studied to evaluate possible impairment of autonomic nervous control of cardiovascular and pulmonary function. The sleep apnea group had subnormal increases in heart rate and blood flow in the resting arm upon muscle contraction, although they were higher than seen in the narcolepsy group. Some sleep apnea patients had marked bradycardia in response to a dive reflex test. Other cardiovascular results did not differ from controls. Some sleep apnea patients had low ventilatory response to CO2. One had abnormal spirometry, two had enlarged tonsils, and five were snorers. The narcolepsy group had subnormal heart rate, blood pressure, and forearm blood flow responses to muscle contraction, subnormal respiratory sinus arrhythmia, and subnormal heart rate response to the Valsalva maneuver. Ventilatory function was normal. Thus, narcolepsy is associated with attenuation of some cardiovascular reflexes. The impairment is probably of central origin. The causative factor for the sleep apnea syndrome is probably also in the central nervous system rather than in the pulmonary or upper airway region. Great interindividual variations in the sleep apnea group point to a more multifactorial etiology. Thus, the two conditions of increased sleepiness are associated with autonomic dysfunction, but the differences in autonomic abnormalities reinforce that sleep apnea and narcolepsy, also in this respect, represent different clinical entities.

Adult↗

[Wallenberg's syndrome with sleep-induced dyspnea--a case study].

One case with Wallenberg's syndrome followed by the neck clipping of the posterior inferior cerebellar aneurysm was reported. The patient was 49 years old female with the subarachnoid hemorrhage, who had previously no history of the cardiovascular disease. The vertebral angiogram revealed a saccular aneurysm of the left vertebral artery at the origin of the posterior inferior cerebellar artery. The preoperative neurological examination were normal, except for the slight degree of the meningeal irritation. The surgical intervention was successfully performed on 39th day after the subarachnoid hemorrhage. Postoperative course was eventful, presenting the typical Wallenberg's syndrome, which was complicated the accompanying signs. The troublesome accompanying signs were chiefly automatic respiratory dysfunction (sleep-induced dyspnea), autonomic dysfunction (Horner's syndrome, perspiration, hypertension), and restless confusion. The postoperative vertebral angiogram showed the obliteration of the aneurysm and the sufficient circulation of the vertebrobasilar system, especially the posterior inferior cerebellar artery. The mechanism of "sleep-induced dyspnea" was discussed in detail from the literatures. In addition to the above mentioned, it should be stressed that the recognition of "sleep-induced dyspnea" and the other accompanying signs are important for the treatment of the patient with the brain stem lesion.

Cerebellar Diseases↗

[Shy-Drager syndrome (multisystem atrophy with progressive autonomic insufficiency). Clinicopathologic study of a case].

The clinical and neuropathological findings in a case of Shy-Drager syndrome in a 56-years-old woman are reported. The patient showed slowly progressive autonomic dysfunctions and additional non-autonomic abnormalities, including pyramidal, extrapyramidal and cerebellar features. The neuropathological examination revealed striatonigral degeneration and olivopontocerebellar atrophy; neuronal loss and reactive gliosis were found also in the pigmented nuclei of the brainstem and in the spinal cord, mainly in the intermediolateral columns. The nosological place of the Shy-Drager syndrome in systemic degenerative diseases is pointed out, and the possible etiopathogenetic mechanisms are briefly discussed.

Female↗

Autonomic nervous system function in multiple sclerosis.

Autonomic dysfunction causes significant disability in patients with multiple sclerosis (MS). Abnormalities of bladder, bowel and sexual function have been well documented in previous studies but cardiovascular and sudomotor autonomic changes have been less frequently reported. The present study has documented autonomic symptoms and results of cardiovascular and sudomotor autonomic function tests in 63 MS patients and correlated these changes with the clinical features of MS.Autonomic symptoms were common in MS patients, the most common being disorders of micturition, impotence, sudomotor and gastrointestinal disturbances, which were associated with increased MS severity. There was no significant association between autonomic symptoms and abnormalities of autonomic investigations. Abnormalities of one or more autonomic function tests, not including those of bladder, gastrointestinal or sexual dysfunction, were present in more than one half of the MS patients. Autonomic dysfunction, defined as abnormalities in two or more tests, was found in 18% of patients and was associated with increased MS severity. Postural hypotension was very uncommon. Parasympathetic cardiovascular autonomic abnormalities occurred in 16% of patients and were associated with increased MS severity. Sympathetic cardiovascular abnormalities were present in 13% of patients and showed no significant association with MS severity. The sympathetic skin response(SSR) was abnormal in nearly one half of the patients and also showed no significant association with MS severity. There was a variable and heterogenous pattern of autonomic test abnormalities found in the MS patients, which were of minor clinical significance except for postural hypotension. Cardiovascular and sudomotor autonomic abnormalities in MS patients are likely to be due to plaques distributed throughout the brainstem and spinal cord affecting anatomically widespread autonomic regulatory areas and their connections.

Adult↗

Autonomic nervous system dysfunction associated with HIV infection in intravenous heroin users.

OBJECTIVE: To evaluate the presence of autonomic nervous system (ANS) involvement in HIV-positive drug users. DESIGN: We investigated 37 HIV-positive (and 18 HIV-negative controls) intravenous heroin users who were without symptoms and signs of autonomic or peripheral neuropathy. METHODS: The patients were clinically and immunologically assessed and subjected to a battery of five cardiovascular reflex function tests. RESULTS: The tests revealed ANS involvement in 22 HIV-positive subjects but only in one HIV-negative subject. Immunoglobulin (Ig) G and C1q immune complex levels were significantly higher in HIV-positive subjects with severe cardiovascular reflex function tests alteration compared to those with normal tests. In a follow-up of 17 HIV-positive subjects, nine presented deteriorated reflexes in the tests and higher IgG immune complex levels. CONCLUSIONS: The results confirm that, by using sufficiently sensitive tests, signs of preclinical autonomic neuropathy can frequently be found in HIV-positive intravenous heroin users, as previously observed in homosexual patients, and suggest the existence of an HIV-related autoimmune pathogenesis. Early diagnosis of ANS involvement could be important, since the presence of autonomic dysfunction could increase the risk of cardiorespiratory arrest during invasive procedures.

Adult↗

[Orthostatic hypotension due to autonomous nervous system dysfunction. Review of different syndromes and their treatment].

Dysfunction of the autonomous nervous system was poorly known to cardiologists until recently. Advances in the diagnosis of vasovagal syncope have initiated intense cardiological research into this subject. This type of syncope does not cover by far all dysfunctions of this system, all or nearly all of which have vasoplegic or bradycardic components. The aim of this article is to review the disorders of the autonomous nervous system which may interest every day practice of the cardiologist. The diagnostic advances and new treatments will require a further update of this review in the months or years to come.

Autonomic Nervous System Diseases↗

[Cardiac sympathetic dysfunction in Parkinson's disease--relationship between results of 123I-MIBG scintigraphy and autonomic nervous function evaluated by the Valsalva maneuver].

We examined whether the results of 123I-MIBG scintigraphy reflect cardiac sympathetic nerve function in patients with Parkinson's disease (PD). The subjects were 62 patients with Parkinson's disease (age, 65.4 +/- 6.3 years) and 53 controls (65.2 +/- 7.1 years). All subjects underwent 123I-MIBG scintigraphy and QTc interval measurement on ECG. Hemodynamic autonomic function was estimated by the Valsalva maneuver in 37 subjects (63.9 +/- 5.2 years) randomly selected from the patients with PD. As control, the Valsalva maneuver was also done in 20 randomly selected controls (64.1 +/- 5.0 years), and 123I-MIBG scintigraphy was performed in 21 controls (67.7 +/- 5.3 years old). The subjects rested in a supine position for 20 min and were given an intravenous injection of 111 MBq 123I-MIBG. Relative organ uptake was determined by the region of interest (ROI) in the anterior view and the ratio of average pixel count in the heart (H) to that in the mediastinum (M) was calculated (H/M ratio) for early (after 15 min) and delayed (after 3 hrs) periods. The Valsalva maneuver was done by having the subjects exhale into a mouthpiece at an expiratory pressure of 40 mmHg for 15 seconds. Blood pressure and RR intervals were measured during the Valsalva maneuver by tonometry, using a noninvasive blood pressure monitoring system (ANS 508, Nihon Colin Co., Ltd.). Baroreceptor reflex sensitivities (BRS) of the second phase (BRS II) and fourth phase (BRS IV) of the Valsalva maneuver were calculated, and blood pressure elevations during the late second phase (IIp) and fourth phase (IVp) were measured. QTc was greater in the patients with PD (417 ms) than in the control subjects (409 ms). The H/M ratios of the early and delayed images in the patients with PD (1.76, 1.61) were significantly lower than those in the control subjects (2.56, 2.45). The early and delayed H/M ratios significantly correlated with the severity of disease according to Hoehn-Yahr stage. QTc interval and IVp significantly correlated with early and delayed H/M ratios. No other significant correlations were detected. The early H/M ratio in the patients with PD who had IVp within the normal range was lower than the early H/M ratio in control subjects. Our results show that early and delayed H/M ratio correlates with cardiac autonomic function, evaluated on the basis of QTc interval and the Valsalva maneuver, but not with baroreceptor reflex sensitivity or vasomotor autonomic function. Our findings suggest that silent cardiac autonomic dysfunction may be evaluated by 123I-MIBG scintigraphy, because early and delayed H/M ratios were lower in the patients with PD who had normal IVp than in the control subjects.

3-Iodobenzylguanidine↗

Autonomic nervous system dysfunction and volume nonresponsive hypotension in hemodialysis patients.

Studies were conducted in 9 dialysis patients with volume-nonresponsive hypotension, 6 dialysis patients with volume-responsive hypotension and in 10 normal subjects in an effort to evaluate the role of dysfunction of the autonomic nervous system (ANS) in the genesis of volume-nonresponsive hypotension. ANS function was evaluated by the Valsalva maneuver, handgrip exercise, and by the response of heart rate and blood pressure to change of posture from a supine to a standing position. Patients with volume-nonresponsive hypotension displayed significant derangements in the function of ANS as compared to normal subjects and to patients with volume-responsive hypotension. Data show that dysfunction of ANS plays an important role in the genesis of volume-nonresponsive hypotension in dialysis patients.

Autonomic Nervous System Diseases↗

Asymptomatic autonomic and sweat dysfunction in patients with Adie's syndrome.

A study was conducted to determine by using noninvasive tests whether autonomic dysfunction occurs in patients with Adie's syndrome. Eighteen consecutive patients with Aide's syndrome prospectively underwent a standardized battery of five noninvasive tests of autonomic function, including three that predominantly reflected parasympathetic function and two that predominantly reflected sympathetic function. Eight of these patients additionally underwent thermoregulatory sweat testing. Of the 18 patients 10 (56%) had no abnormal autonomic test results, 5 (28%) had one abnormal result, 2 (11%) had two abnormal results, and 1 (6%) had three abnormal results. None of the patients had more than three abnormal results. Tests that predominantly reflected parasympathetic function produced abnormal results more frequently than those that predominantly reflected sympathetic function. Three of eight (38%) patients who underwent thermoregulatory sweat testing showed abnormal patterns of sweating. Although abnormal autonomic and sweat functions are not uncommon in patients with Aide's syndrome, the abnormalities are mild and are generally unassociated with symptoms of dysautonomia. Such abnormalities have little clinical significance but may be important from a nosologic point of view.

Adie Syndrome↗

Complexities in ETS-domain transcription factor function and regulation: lessons from the TCF (ternary complex factor) subfamily. The Colworth Medal Lecture.

The ETS-domain transcription factor family can be divided into a series of subfamilies. Elk-1 represents the founding member of the ternary complex factor (TCF) subfamily. By focusing on the TCF subfamily, we can demonstrate the complexities that exist in the function and regulation of ETS-domain transcription factors. This article focuses on Elk-1 in detail and summarizes the functions of other TCFs. The key themes covered include the domain structure of the TCFs, the mechanisms of complex formation with serum response factor, regulation of TCFs by mitogen-activated protein kinase cascades, and transcriptional regulatory properties of the TCFs. Finally, the emerging role of the TCFs in vivo is discussed. A picture is developing indicating that, while these proteins exhibit significant sequence and functional conservation, key differences in their structure and regulation are being identified which may relate to unique functions of these proteins in vivo.

Amino Acid Sequence↗

Autonomic performance and dehydroepiandrosterone sulfate levels in HIV-1-infected individuals: relationship to TH1 and TH2 cytokine profile.

BACKGROUND: Products of immune activation, including cytokines and lipid membrane derivatives, have been implicated in the pathogenesis of the neurologic sequelae, including autonomic dysfunction, associated with human immunodeficiency virus 1 (HIV-1) infection. In animal models, autonomic and endocrine dysfunction are associated with an altered cytokine profile. OBJECTIVES: To investigate the relationship between markers of immune activation (beta(2)-microglobulin), HIV-1 disease progression (CD4(+) cell count and viral load), and autonomic nervous system performance and to assess the relationship between autonomic performance, plasma levels of dehydroepiandrosterone sulfate (DHEAS), and T(H)1 and T(H)2 cytokine profile. METHODS: Thirty-one HIV-1-infected individuals and 22 HIV-1-negative controls were evaluated with a comprehensive neurologic, neuropsychological, and autonomic examination. Interleukin 4 and interferon gamma were measured by enzyme-linked immunosorbent assay in the supernatant of stimulated peripheral blood mononuclear cells. RESULTS: A composite measure of autonomic performance (AZ score) was significantly lower (worse autonomic function) in patients compared with controls (P=.04). A lower AZ score was associated with higher beta(2)-microglobulin serum levels and a lower CD4(+) cell count. Interleukin 4 levels were significantly inversely associated with AZ score (P=.01), whereas interferon gamma levels were significantly positively associated with DHEAS levels (P=.04). CONCLUSIONS: Our data show significant associations between markers of immune activation and disease progression and a composite measure of autonomic function in HIV-1-infected individuals. In addition, they suggest that poor autonomic function and low DHEAS plasma levels tend to be associated with an unbalanced cytokine profile.

Adult↗