SEARCH · PubMed Health

Results for “Autonomic dysfunction”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,099 records · Page 61Linked to original sources

PubMed1996

Biochemical and pharmacologic assessment of autonomic function.

Autonomic failure produces distinct pathophysiological abnormalities that differ according to the site and nature of the lesion(s). Although the anatomic organization and processes mediating chemical neurotransmission in the autonomic nervous system facilitate clinical investigation, limited access to the central compartment hampers evaluation of central neurotransmitter metabolism and neuropeptide function. As illustrated in the discussions of noradrenergic and cholinergic function, several indirect strategies have been used to assess the biochemical and neuropharmacologic consequences of autonomic dysfunction. The methods validated in patients with autonomic failure can be applied to investigate autonomic function in other clinical disorders including Parkinson's disease. The results of such studies may help to guide therapy and develop improved strategies for managing those patients with autonomic insufficiency.

Autonomic Nervous System↗

PubMed1995

[Function of the autonomic nervous system in uremia].

Autonomic impairement is associated with poor prognosis in many diseases. The article (first of three parts) critically reviews arguments found in the literature showing autonomic dysfunction in chronic renal failure patients. The autonomic nervous system problems will become of great clinical relevance considering increasing number and age of uremic patients being dialysed worldwide.

Animals↗

PubMedDate not supplied

Autonomic nervous system dysfunction involving the gastrointestinal and the urinary tracts in primary Sjögren's syndrome.

OBJECTIVE: Antibodies reacting with the m3 subtype muscarinic acetylcholine receptor appear to be an important pathogenic factor in primary Sjögren's syndrome (pSS). As this receptor subtype is functionally important in the gastrointestinal and urinary tracts, and very little is known about the autonomic nervous system function in these organs in pSS patients, the occurrence and clinical significance of an autonomic nervous system dysfunction involving the gastrointestinal and urinary tracts were investigated. METHODS: Data on clinical symptoms attributable to an autonomic dysfunction were collected from 51 pSS patients. Gastric emptying scintigraphy and urodynamic studies were performed on 30 and 16 patients, respectively, and the results were correlated with patient characteristics and with the presence of autonomic nervous system symptoms. RESULTS: Gastric emptying was abnormally slow in 21 of the 30 examined patients (70%). Urodynamic findings, compatible with a decreased detrusor muscle tone or contractility were found in 9 of the 16 patients tested (56%). Various symptoms of an autonomic nervous system dysfunction were reported by 2-16% of the patients. CONCLUSION: Signs of an autonomic nervous system dysfunction involving the gastrointestinal and the urinary systems can be observed in the majority of pSS patients. This high occurrence is rarely associated with clinically significant symptoms. The authors presume a role of autoantibodies reacting with the m3 muscarinic acetylcholine receptor in the elicitation of the autonomic dysfunction.

Adult↗

PubMed1994

Gastrobiliary motility after liquid fatty meal in progressive systemic sclerosis. A sonographic study.

Gastric emptying, antral motility, and gallbladder emptying after a liquid fatty meal were studied by ultrasound in 25 patients with progressive systemic sclerosis and in 25 sex- and age-matched controls. In patients with systemic sclerosis, the possible role of autonomic dysfunction was evaluated by four noninvasive cardiovascular reflex tests. Despite a significant delay of gastric emptying and a significant postprandial antral hypomotility in the patients with systemic sclerosis, the fat-induced gallbladder emptying was only slightly reduced, reaching no significant level when compared to the controls. The prolongation of gastric emptying correlated significantly with the duration of the disease. Although 36% of the patients in the systemic sclerosis group exhibited signs of autonomic cardiac dysfunction, there was no evidence of an association between these signs and gastric motor dysfunction. In conclusion motility disorders of the gallbladder seem to play a minor role in the upper gut involvement of systemic sclerosis, whereas motility disorders of the stomach are frequent and can be easily recognized noninvasively by real-time ultrasound.

Adult↗

PubMed1999

Orthostatic hypotension in Alzheimer's disease: result or cause of brain dysfunction?

In Alzheimer's disease (AD), an association was found between autonomic dysfunction and frontal hypoperfusion in brain during orthostatic testing. To ascertain whether frontal hypoperfusion is dependent on longitudinal effects of hemodynamic disturbances, or contributes to them, we studied the relationship between the presence of orthostatic hypotension (OH) and resting cerebral blood flow (CBF) in late stages of AD. Twelve women with senile dementia of Alzheimer type (SDAT), and 15 non-demented women (mean age 82.6 years, SD 3.8 vs 81.8 years, SD 3.5) were examined with the orthostatic test. Four of 12 patients with SDAT, and 9 controls had OH (defined as systolic blood pressure fall > or = 20 mmHg). CBF was determined under resting conditions using 600 Mbq 99mTc HMPAO single photon emission computerized tomography (SPECT), and quantified in cortical areas in relation to cerebellum. In patients with SDAT and OH, CBF was lower in frontal and parieto-frontal cortical areas than in SDAT patients without OH. The former group was younger and had a shorter dementia duration. No significant differences in CBF were observed between controls with vs without OH. No differences in SDAT patients with or without OH were observed in the Berger dementia scale or Katz' ADL index. No difference in incidence of symptoms related to autonomic disturbances (diarrhea, obstipation, dysphagia, vertigo) was observed in either the SDAT or control group with regard to OH presence. We conclude that during the course of AD, OH can contribute to frontal brain changes and may exacerbate the disease. The further involvement of frontal dysfunction in aggravating blood pressure dysregulation in the elderly is discussed.

Aged↗

PubMed2005

Autonomic nervous system dysfunction in lightning and electrical injuries.

Autonomic nervous system (ANS) dysfunction is a serious complication of lightning and electrical trauma (L/ET). The ANS regulates the normal vegetative functioning of many organ systems. When ANS is compromised after lightning and electric trauma, patients are vulnerable to serious medical problems. Three conditions of ANS dysfunction of particular concern for L/ET patients are complex regional pain syndrome (CRPS), cardiovascular abnormalities, and keraunoparalysis (KP). The patient with CRPS presents with pain, hyperpathia, sweating, and edema hours to days after trauma. Neurorehabilitation is exceedingly important. A primary goal is to keep the affected extremity mobile and functional. Some patients benefit from sympathetic blockade. Cardiovascular abnormalities associated with lightning and electrical trauma can be life threatening. Care for these patients require a multidisciplinary team including a cardiologist. Keraunoparalysis is a frightening and distressing complication of lightning strikes. The syndrome consists of limb paralysis, sensory symptoms, pallor, coolness and absent pulses. Release of excessive catecholamines is said to be responsible for these findings. Fortunately, the condition is transient.

Arrhythmias, Cardiac↗

PubMed1987

Infant botulism--the first reported case from Queensland.

Infant botulism is a rare disease with previous reports in Australia originating from its southern states. The first case to be recognized from Queensland is described in a four-month-old white girl. Complications included respiratory failure, the syndrome of inappropriate antidiuretic hormone secretion, urinary tract infection and autonomic dysfunction.

Australia↗

PubMed2006

Dysautonomia and ventricular dysfunction in the indeterminate form of Chagas disease.

BACKGROUND: The associations between autonomic function and biventricular function in patients with the indeterminate form of Chagas disease remains to be elucidated. METHODS: In 42 asymptomatic patients and 19 healthy volunteers, the autonomic function was assessed by time domain indices of heart rate variability (HRV), analyzed for 24 h; the right ventricular function was assessed by fraction area change, right ventricle shortening, and systolic excursion of the tricuspid valve; and the left ventricular function was assessed by ejection fraction and transmitral flow velocities. Data were expressed as mean+/-SD or medians (including the lower quartile and upper quartile). Groups were compared by Student's t or Mann-Whitney U test. Autonomic and ventricular function were correlated by Pearson's or Spearman's correlation coefficient. The level of significance was 5%. RESULTS: Right and left ventricular systolic function indexes were comparable between groups. Transmitral flow velocities were decreased in the Chagas disease group (p<0.05). The patients presented impaired HRV as indicated by the values of SDNN-day (80 (64-99) ms vs. 98 (78-127) ms; p=0.045), SDNNI-24 h (54 (43-71) vs. 65 (54-105) ms; p=0.027), SDNNI-day (49 (42-64) vs. 67 (48-76) ms; p=0.045), pNN50-day (2.2 (0.7-5)% vs. 10 (3-11)%; p=0.033); and pNN50-24 h (3 (1-7)% vs. 12 (8-19)%; p=0.013). There were no correlations between the left ventricular diastolic indices and autonomic dysfunctional indices (p>0.05). CONCLUSION: Patients with the indeterminate form of Chagas disease have both dysautonomia and left ventricular diastolic dysfunction. However, the right ventricular function is preserved. Importantly, ventricular diastolic dysfunction and dysautonomia are independent phenomena.

Adult↗

PubMed2003

Influence of autonomic nervous system dysfunction on the development of type 2 diabetes: the CARDIA study.

OBJECTIVE: We investigated whether autonomic nervous system dysfunction, estimated by slow heart rate recovery (HRR) following cessation of an exercise treadmill test, was associated with increases in insulin and glucose over time and the development of type 2 diabetes. RESEARCH DESIGN AND METHODS: Maximal exercise tests were performed by 3295 healthy adults aged 18-30 years in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Repeat measurements of insulin and glucose collected at 7-, 10-, and 15-year examinations were compared by quartiles of HRR (maximum heart rate minus heart rate 2 min after cessation of the test). Incident diabetes was identified at any follow-up examination as glucose >or=7 mmol/l or the use of diabetes control medication. RESULTS: Among participants who did not develop diabetes, fasting insulin concentrations increased from baseline to year 15. Following adjustment (for age, race, sex, smoking status, and BMI), participants with the slowest HRR (quartile 1) had higher fasting insulin at each examination than participants with faster HRR (e.g., year 15 examination: 88.1 vs. 81.3 pmol/l for quartile 1 vs. quartile 4, respectively, P = 0.05). Glucose did not differ by quartile of HRR at any examination. Among participants with poor fitness, the risk of developing diabetes (n = 98) was 3.4-fold greater (95% CI 1.5-8.0) when HRR was <42 vs. >42 bpm. This persisted following adjustment for baseline insulin. CONCLUSIONS: Autonomic dysfunction, in combination with poor physical fitness, may be a mechanism associated with early glucose dysmetabolism and the development of diabetes.

Adult↗

PubMed1991

High frequency of human immunodeficiency virus-associated autonomic neuropathy and more severe involvement in advanced stages of human immunodeficiency virus disease.

We conducted a controlled trial to determine frequency and severity of autonomic neuropathy in patients infected with the human immunodeficiency virus (HIV). We studied 25 HIV-seropositive patients and 10 seronegative controls in HIV risk groups by means of five cardiovascular tests, and autonomic neuropathy was graded with a scoring system. The overall autonomic test score differed between patients and controls and was higher in patients with advanced (Centers for Disease Control class IV) disease than in those with earlier (class II or III) HIV disease. Of the patients, 60% had findings of autonomic dysfunction. Our data demonstrate a high prevalence of autonomic neuropathy in HIV-infected patients. Advanced HIV disease is associated with more severe involvement than earlier disease states.

Adult↗

PubMed1992

Role of autonomic nerve functions in patients with familial amyloidotic polyneuropathy as analyzed by laser Doppler flowmetry, capsule hydrograph, and cardiographic R-R interval.

Laser Doppler flowmetry (LDF) was conducted on familial amyloidotic polyneuropathy (FAP) patients and asymptomatic carriers of FAP. Vasoconstrictive responses in the 11 FAP patients tested, induced by deep inspiration, were markedly depressed compared with those of the healthy controls. The responses decreased with the progression of FAP, with no responses being elicited from the 7 patients in stages 2 (moderate) to 4 (terminal). Interestingly, vasoconstrictive responses following deep inspiration also were depressed in 3 of 4 asymptomatic carriers of FAP who showed no clinical sign of FAP, and who had normal sensory nerve conduction velocity. Patients who had such diseases as Shy-Drager's disease, spinocelebellar degeneration, and pandysautonomia showed no decrease in blood flow for various stimulations. In contrast, patients with primary amyloidosis, who had no autonomic dysfunction, showed a normal pattern. Detection of the autonomic functions in FAP patients and asymptomatic carriers by capsule polyhydrography and computer analysis of the cardiographic R-R interval revealed that the asymptomatic carriers of FAP, as well as the FAP patients, had disordered peripheral autonomic functions. Our results suggest that the autonomic nervous system is first affected during the very early stage of FAP.

Adult↗

PubMed2000

Sleep apnoea in children with diabetes mellitus: effect of glycaemic control.

AIMS/HYPOTHESIS: Patients with diabetes mellitus commonly have cardiovascular autonomic dysfunction and an abnormal ventilatory pattern during sleep. Few data are available on these changes in childhood diabetes. We investigated whether young diabetic children with or without diabetic neuropathy have ventilatory dysfunction during sleep and if so, whether these autonomic changes are related to the duration of diabetes and glycaemic control. METHODS: We studied 25 children with insulin-dependent diabetes mellitus (19 boys, mean age 7.72 +/- 1.99 years). All patients were insulin-dependent at diagnosis; blood samples for HbA1c assay were collected on the morning before testing and at 3-month intervals during the preceding year. Patients and control subjects (20 age-matched healthy children, 15 boys) underwent overnight polysomnography. RESULTS: More diabetic patients than control subjects had sleep apnoeas (p = 0.006); apnoeas in patients also lasted longer (p = 0.07). Patients with poorly controlled diabetes had more apnoeas than patients with well-controlled diabetes and than healthy control subjects (p < 0.0001). Respiratory events during sleep correlated significantly with glycaemic control (r = 0.360; p = 0.09) and with the duration of diabetes (r = 0.430; p = 0.04). CONCLUSION/INTERPRETATION: We conclude that respiratory control is compromised very early in children with diabetes. These anomalies are closely related to the duration of diabetes and to glycaemic control. In young children with diabetes, screening of ventilatory control using recording techniques that are simpler than polysomnography could provide an early indication that an adverse cardiopulmonary reaction has begun.

Blood Glucose↗

PubMed2002

Ion channel-directed therapies in autonomic neurons: a view from the bench.

Voltage-gated and ligand-gated ion channels have been mapped in autonomic neurons. Furthermore, clinical pathology is associated with altered function of certain ion channels in autonomic neurons, most by channel-binding auto-antibodies. Medications that are directed to ion channels account for a major pharmaceutical market segment. Ion channel-directed drug therapies may be used to treat autonomic dysfunction. In turn, drug therapies for non-autonomic disorders (e. g., for cardiac disorders) often have unwanted effects on autonomic regulation. Within the last decade, we have witnessed an explosion of information about the molecular details of ion channel biology. Knowledge of ion channel molecular biology paired with advances in screening technologies and gene therapy may be useful for developing new ion channel-directed therapies.

Animals↗

PubMed1999

Studies of autonomic function in patients with achalasia and nutcracker oesophagus.

BACKGROUND: Post-mortem studies in patients with achalasia reveal degenerative changes in the vagus and its dorsal motor nuclei suggesting the possibility of widespread autonomic dysfunction. AIMS: To study a broad range of autonomic function in patients with achalasia and nutcracker oesophagus and in asymptomatic volunteers. SUBJECTS: Patients with a manometric diagnosis of achalasia and nutcracker oesophagus and age- and sex-matched asymptomatic volunteers. METHODS: Subjects underwent measurement of: (1) pupil cycle time estimation; (2) heart rate response to the Valsalva manoeuvre, standing and deep breathing; (3) systolic blood pressure response to standing; (4) diastolic response to sustained handgrip; (5) spectral analysis of heart rate variability; and (6) heart rate and blood pressure during the Valsalva manoeuvre. RESULTS: No significant differences were found between patients with achalasia and asymptomatic volunteers. Patients with nutcracker oesophagus, however, had longer pupil cycle times (1.2 (0.9-1.4) s versus 0.9 (0.8-1.2) s, P= 0.02) and had attenuation of both the rise in the low frequency peak of heart rate variability and the fall in the high frequency peak on standing (rise in low frequency peak - patients 26.6 (10.4-52.3)% to 42.2 (15.5-54.0)%, P = 0.46, volunteers 16.9 (8.4-37.2)% to 47.4 (21.1-66.3)%, P = 0.03; fall in high frequency peak - patients 18.1 (0.9-43.3)% to 10.1 (0.5-26.6)%, P= 0.46, volunteers 24.8 (8.5-44.4)% to 9.3 (2.6-35.6)%, P= 0.03). The rise in blood pressure during the Valsalva manoeuvre was also attenuated in patients with nutcracker oesophagus compared with asymptomatic volunteers (6.9 (1.0-9.3) mmHg versus 12.9 (11 -23.0) mmHg, P < 0.01). CONCLUSIONS: Whereas tests of cardiovascular and pupillary autonomic function are normal in patients with achalasia, patients with nutcracker oesophagus show defects in both parasympathetic and sympathetic function.

Adult↗

PubMed1996

Stimulus-evoked sinus arrest in severe Guillain-Barré syndrome: a case report.

Guillain-Barré syndrome, or acute inflammatory demyelinating polyradiculoneuropathy, is frequently accompanied by cardiac and autonomic dysfunction. We report a patient in whom minor autonomic stimulation by upgaze, tongue protrusion, opening the mouth against resistance, eyeball pressure, and carotid sinus massage produced asystole. The frequency of potentially lethal dysrhythmias in Guillain-Barré syndrome, coupled with the relative ease of cardiac pacing, makes recognition of these phenomena of utmost importance in affected patients.

Adult↗

PubMedDate not supplied

Electromyographic mixed nerve and cutaneous silent period in evaluating the A-delta fibres in a patient with hereditary sensory-autonomic neuropathy.

The aim of this study was to evaluate A-delta fibre function in a patient with hereditary sensory-autonomic neuropathy (HSAN). We used the mixed and cutaneous silent period techniques in addition to a conventional electromyographic investigation in a patient with type 2 HSAN, a rare disease characterised by wide-spread sensory and variable autonomic dysfunction caused by incomplete development of sensory and autonomic neurons. Whereas the stimulation of one digital nerve did not show any evidence of silent period in either the left or the right hand, the simultaneous stimulation of two digital nerves, as well as the stimulation of a mixed nerve, revealed a measurable delayed and shortened silent period. These data suggest that a spatial summation mediated by A-delta fibres was required for generation of the silent period in this patient and that combining the CSP and MNSP may be of practical use in evaluating impairment of the small myelinated fibres.

Adult↗

PubMed1990

[Autonomic nervous functions in Alzheimer type and multi-infarct dementia--a hemodynamic study].

As it has been recently postulated that patients with dementia have some altered neural transmission, these patients are speculated to accompany autonomic dysfunctions. The present study was aimed at investigating autonomic nervous functions in dementia of Alzheimer type (DAT) and multi-infarct dementia (MID). Hemodynamic autonomic functional tests were carried out on 14 patients with DAT (66.9 +/- 11.4 YO; mean +/- SD) and 9 patients with MID (73.1 +/- 7.5) and 16 age-matched healthy volunteers as controls. Blood pressure, pulse rate and respiration were continuously measured. The degree of reflex bradycardia in Aschner's test, a parameter for parasympathetic functions, was significantly lower in MID than in DAT and in the healthy volunteers (p less than 0.01, p less than 0.05, respectively), but there was no significant difference between DAT and the healthy volunteers in this reaction. The degree of reflex hypertension in cold pressor test, a parameter for sympathetic functions, was not significantly different among 3 groups. The degree of orthostatic hypotension also failed to show any significant difference among the groups. From the above data, it is suggested that the patients with DAT have preserved autonomic nervous functions, but that the patients with MID have impaired parasympathetic and normal sympathetic nervous functions.

Aged↗

PubMed1997

Autonomic dysreflexia: pharmacological management of hypertensive crises in spinal cord injured patients.

Interruption of autonomic pathways by spinal cord injury (SCI) causes dysfunctional autonomic dysreflexia (AD), which was first described in 1917, still remains unrecognized by those in the medical profession not involved in SCI care. Autonomic dysreflexia is a syndrome generally manifest by cardiovascular symptoms and characterized by paroxysmal hypertension. These symptoms appear in patients with spinal cord injury above the sympathetic outflow from the spinal cord (T6). Since patients with high level SCI are usually hypotensive, the high blood pressures that develop during AD represent pressure changes of a magnitude that can cause cerebrovascular accidents and death of the subject. We discuss the therapeutic interventions that abate and curtail the symptoms and prevent the catastrophic sequelae of autonomic dysreflexia.

Autonomic Nervous System Diseases↗