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PubMed2001

Autonomic consequences of brainstem infarction.

OBJECTIVE: It is well known that patients with brainstem infarctions sometimes experience dizziness, vertigo and falls, although the exact mechanism is not clear. Therefore, we designed a study to quantify autonomic function in patients with brainstem infarction. PATIENTS AND METHODS: We examined autonomic function in 15 patients with brainstem infarctions, who had a history of vertigo, nausea, floating sensation and/or general fatigue during standing, and 31 age-matched controls using the composite autonomic scoring scale (CASS), which was used to grade autonomic function. The patients underwent initial autonomic assessment and then were subjected to aniracetam therapy. The drug was given orally (dose of 600 mg/day) for a duration of 56 days. Upon completion of aniracetam administration, the CASS was again tested. RESULTS: Upon initial assessment, the patients had mild reductions in mean blood pressure (MBP) and lack of an increasing heart rate (HR) within 5 min of head up-tilt, an impairment in BP correction during late phase II and reduced phase IV beat-to-beat BP response to the Valsalva maneuver, and reduced heart rate response to deep breathing (HRdb). CASS indicated mild autonomic dysfunction. After 8 weeks of treatment with aniracetam, the patients' symptoms improved and the autonomic tests showed improvement in autonomic function. CONCLUSION: Part of the pathogenesis of recurrent vertigo or dizziness with brainstem infarction might be due to mild autonomic dysfunction. Aniracetam, which activates the cholinergic system in brain, might correct the cardiovagal system in these patients. The CASS may be a sensitive tool for assessing mild autonomic dysfunction in patients with brainstem infarction.

Aged↗

PubMed2000

Three-dimensional return map: a new tool for quantification of heart rate variability.

BACKGROUND: Several methods are used to study heart rate variability, but they have limitations, which might be overcome by the use of a three-dimensional return map. OBJECTIVES: To evaluate the performance of three-dimensional return map-derived indices to detect (1) sympathetic and parasympathetic modulation to the sinus node and (2) autonomic dysfunction in diabetic patients. METHODS: Six healthy subjects underwent partial and total pharmacological autonomic blockade in a protocol that incorporated vagal and sympathetic predominance. Twenty-two patients with type 2 diabetes mellitus and 12 normal controls participated in the subsequent validation experiment. Three-dimensional return maps were constructed by plotting RRn intervals versus the difference between adjacent RR intervals [(RRn+1)-(RRn)] versus the number of counts, and four derived indices (P1, P2, P3, MN) were created for quantification. RESULTS: Both indices P1 and MN were significantly increased after sympathetic blockade with propranolol, while all indices except P1 were modified after parasympathetic blockade (P < 0.05). During the validation experiments, P1 and MN detected differences between normal controls, and diabetic patients with and without autonomic neuropathy. The overall accuracy of most three-dimensional indices to detect autonomic dysfunction, estimated by the area under the ROC curve, was significantly better than traditional time domain indices. Three-dimensional return map-derived indices also showed adequate reproducibility on two different recording days (intra-class correlation coefficients of 0.69 to 0.82; P < 0.001). CONCLUSIONS: Three-dimensional return map-derived indices are reproducible, quantify parasympathetic as well as sympathetic modulation to the sinus node, and are capable of detecting autonomic dysfunction in diabetic patients.

1-Propanol↗

PubMed1985

Autonomic neuropathy associated with autoimmune disease.

Mononeuropathy multiplex and mixed sensorimotor neuropathy are known complications of systemic vasculitis and related autoimmune disorders. Autonomic dysfunction is not generally considered a neurologic complication of these diseases. We report two patients who came to neurologic attention because of autonomic dysfunction and were then discovered to have autoimmune disease. Autonomic dysfunction may be the presenting sign of autoimmune disorders, which should be considered in the differential diagnosis of acquired autonomic disturbances.

Adult↗

PubMed2002

Cardiac autonomic nervous dysfunction in diabetic patients with a mitochondrial DNA mutation: assessment by heart rate variability.

OBJECTIVE: To elucidate the degree and characteristics of cardiac autonomic nervous dysfunction in diabetic patients associated with a mitochondrial DNA mutation at base pair 3243. RESEARCH DESIGN AND METHODS: We investigated heart rate variability using 24-h Holter monitoring in 10 diabetic patients with the mutation compared with 55 ordinary diabetic patients and 45 nondiabetic control subjects. RESULTS: Age and sex were similar in the three groups. Between patients with the mutation and ordinary diabetic patients, the duration of diabetes and blood glycemic levels were not different. In the time domain analysis of heart rate variability, patients with the mutation and ordinary diabetic patients had significantly smaller SDNN index and pNN50 than control subjects. Compared with ordinary diabetic patients, patients with the mutation had smaller SDNN index (P < 0.02), but rMSSD and pNN50 were not different. In the frequency domain analysis, total, low frequency (LF), and high frequency (HF) spectra were significantly smaller in patients with the mutation and ordinary diabetic patients than in control subjects. Compared with ordinary diabetic patients, patients with the mutation had smaller total and LF spectra (P < 0.02). However, HF spectra were not significantly different. Notably, the LF/HF spectra ratio was lower in patients with the mutation than in ordinary diabetic patients and control subjects (P < 0.05), but this ratio was similar in ordinary diabetic patients and control subjects. CONCLUSIONS: Our results suggest that diabetic patients with the mitochondrial DNA mutation have more severely impaired cardiac autonomic nervous function with sympathovagal imbalance, as compared with ordinary diabetic patients.

Age of Onset↗

PubMed1987

Disorders of the autonomic nervous system: Part 1. Pathophysiology and clinical features.

Autonomic dysfunction may result from diseases that affect primarily either the central nervous system or the peripheral autonomic nervous system. The most common pathogenesis of disturbed autonomic function in central nervous system diseases is degeneration of the intermediolateral cell columns (progressive autonomic failure) or disease or damage to descending pathways that synapse on the intermediolateral column cells (spinal cord lesions, cerebrovascular disease, brainstem tumors, multiple sclerosis). The peripheral autonomic nervous system may be damaged in isolation in the acute and subacute autonomic neuropathies or in association with a generalized peripheral neuropathy. The peripheral neuropathies most likely to cause severe autonomic disturbance are those in which small myelinated and unmyelinated fibers are damaged in the baroreflex afferents, the vagal efferents to the heart, and the sympathetic efferent pathways to the mesenteric vascular bed. Acute demyelination of the sympathetic and parasympathetic nerves in the Guillain-Barré syndrome may also cause acute autonomic dysfunction. Although autonomic disturbances may occur in other types of peripheral neuropathy, they are rarely clinically important.

Autonomic Nervous System↗

PubMed2001

Cardiac autonomic function in Blacks with congestive heart failure: vagomimetic action, alteration in sympathovagal balance, and the effect of ACE inhibition on central and peripheral vagal tone.

Cardiac autonomic dysfunction is common in heart disease with or without congestive heart failure, and can cause sudden cardiac death. However, cardiac autonomic abnormalities in non-ischemic (hypertensive) heart failure, which is prevalent in Black Africans is poorly documented. We conducted a cross-sectional study of 32 patients with congestive heart failure, mostly secondary to hypertension (aged 52 +/- 15 years, with ejection fraction of 0.38 +/- 11) and 30 age- and sex-matched healthy volunteers (aged 51 +/- 11 years, 14 males/16 females). Cardiac autonomic function was assessed by the Valsalva's maneuver, respiratory sinus arrhythmia (for cardiac vagal tone) and the pressor and chronotropic changes following forearm isometric handgrip exercise and the assumption of upright posture (tests of sympathetic function). The exercise tolerance of the cardiac patients was assessed by the distance covered during 6 min of walking. The Valsalva ratio was significantly lower in chronic heart failure, 1.10 +/- 0.08 compared to the healthy controls 1.47 +/- 0.20 (p<0.001). Specifically, the phase IV bradycardia in heart failure, was significantly attenuated to 650 +/- 121 msec compared to the value of 935 +/- 101 msec in healthy controls (p<0.001). The phase 11 Valsalva tachycardia did not differ between the patients and controls. The respiratory sinus arrhythmia was also significantly reduced in chronic heart failure (p<0.05) compared to controls. Treatment of the heart failure patients with enalapril-digoxin and diuretics by 4 weeks, resulted in a reversal of the autonomic abnormalities. The phase IV bradycardia increased significantly to 798 +/- 164 msec (p<0.01) and the Valsalva ratio to 1.35 +/- 0.25 (p<0.01) and the respiratory sinus arrhythmia increased toward normal. There was close positive correlation between the Valsalva's ratio and the 6 min self paced distance covered (r = 0.44, p = 0.03 ANOVA), and a weak inverse correlation to cardiac size and cardiothoracic ratio (r = -0.31, p = 0.09). This study demonstrates cardiac autonomic dysfunction (especially reduced vagal tone) in Black Nigerians with mainly non-ischemic congestive heart failure. The parasympathetic dysfunction significantly correlates with severity of heart failure. Current treatment reverses autonomic dysfunction to values seen in healthy age matched controls, mainly through augmentation of cardiac parasympathetic activity.

Adult↗

PubMed2003

Autonomic neuropathy in patients with hepatic cirrhosis.

BACKGROUND: Autonomic neuropathy has been reported in patients with alcoholic liver disease but information on its occurrence in patients with non-alcoholic liver disease is contradictory. AIM: To assess autonomic functions in patients with alcoholic and non-alcoholic liver disease. STUDY DESIGN: Autonomic function using five standard tests was examined in 20 cirrhotics (10 alcoholics and 10 non-alcoholics) and 20 age and sex matched controls. The extent of autonomic dysfunction was determined in the patients and a comparison between the characteristics of patients with and without autonomic neuropathy was made. RESULTS: Sixteen (80%) of the cirrhotic subjects were found to have evidence of autonomic neuropathy. Of these, three (15%) patients had early parasympathetic damage, five (25%) had definite parasympathetic damage, and eight (40%) had combined (that is, both parasympathetic and sympathetic) damage. Nine (90%) of the alcoholics and seven (70%) of the non-alcoholics had autonomic dysfunction. Only one patient belonging to the alcoholic group had clinical evidence of peripheral neuropathy. Moreover, there was no significant association between subjective symptoms of autonomic neuropathy and objective evidence of autonomic damage as assessed by autonomic function tests. Autonomic dysfunction was significantly more frequent in advanced liver disease compared with early liver damage. Nine (75%) out of 12 cirrhotic subjects belonging to Child class B and six (85.7%) of the seven patients belonging to Child class C had autonomic neuropathy. CONCLUSION: This study shows that autonomic neuropathy is common in cirrhotic subjects, that it is found with comparable frequency in alcoholics and non-alcoholics, and that it increases in severity with increase in extent of liver damage, suggesting that liver damage contributes to the neurological deficit.

Autonomic Nervous System Diseases↗

PubMed2000

Physiological, pharmacological and neurohormonal assessment of autonomic function in progressive supranuclear palsy.

The clinical features of progressive supranuclear palsy (PSP) overlap with other parkinsonian syndromes, including multiple system atrophy (MSA). Autonomic dysfunction is a characteristic of MSA, but has also been described in PSP. We therefore report results from a series of physiological studies of cardiovascular autonomic function in 35 PSP and 20 MSA subjects, and 26 age-matched healthy control subjects. The response to growth hormone-clonidine testing, a neuropharmacological assessment of central adrenoceptor function, was also assessed in 14 PSP and 10 MSA subjects, and compared with 10 controls. None was on medication which may have affected the results. Orthostatic hypotension did not occur in PSP subjects or controls, unlike MSA subjects. Overall there was no evidence of sympathetic vasoconstrictor failure in PSP subjects, unlike MSA subjects, although the pressor response to mental arithmetic was reduced. Cardiac parasympathetic function was affected in only a minority (three of 35) of PSP subjects and was abnormal in MSA subjects. After clonidine administration, growth hormone rose in PSP subjects (median increase 4.3; interquartile range 1.8-7.8 mU/l) and controls, unlike MSA subjects (0.9; 0.3-2.4 mU/l; P < 0.005, Mann-Whitney U-test). In conclusion, in PSP subjects, responses to both physiological and pharmacological tests provided evidence against widespread autonomic dysfunction; this differed markedly from MSA subjects. Thus, cardiovascular autonomic dysfunction should be an exclusionary feature in the diagnosis of PSP.

Adrenergic alpha-Agonists↗

PubMed2000

Abnormal heart rate variability in adults with growth hormone deficiency.

GH-deficient (GHD) patients have increased risk of cardiovascular death and may have cardiac structural abnormalities. In non-GHD patients these are associated with cardiac autonomic dysfunction, and it is possible that autonomic dysfunction is also present in GHD patients. Power spectral analysis (PSA) of heart rate variability (HRV) indirectly measures cardiac autonomic tone and generates peaks at 3 frequency bands, very low frequency (VLF), low frequency (LF) and high frequency (HF). The area under the LF curve is considered to reflect predominantly cardiac sympathetic activity, whereas HF indicates parasympathetic activity. PSA of HRV was performed in 14 normotensive GHD patients (5 men and 9 women; mean age, 35.2 yr) and 19 healthy controls (9 men and 10 women; mean age, 38.3 yr). GHD patients had 26% lower normalized LF power (P < 0.004), 39% higher normalized HF power (P < 0.001), 28% lower normalized VLF power (P < 0.046), and 51% lower LF/HF ratio (an index of sympathovagal balance; P < 0.001) compared to controls. These data indicate that heart rate variability is abnormal in patients with GHD. The decreased sympathetic tone could be a consequence of reduced central sympathetic tone or altered cardiac responsiveness to autonomic control and may contribute to the increased cardiovascular risk in GHD patients.

Adult↗

PubMed1995

Changes in the sweatspot test with ageing and relation to cardiovascular autonomic function.

The sweatspot test assesses the local sweat response to an intradermal injection of acetylcholine. It has been reported as a more sensitive indicator of autonomic dysfunction in important diabetic men than either pupillary or cardiovascular tests, and has been used to establish the presence of autonomic dysfunction in patients with idiopathic chronic constipation. However, the usefulness of this test as a simple and quick method of diagnosing autonomic dysfunction in an elderly population has not been established. This is important given the high prevalence of reduced autonomic function with ageing and hypertension. We compared the age-associated responses in the sweatspot test and its relation to cardiovascular autonomic function in elderly normotensive and hypertensive subjects. We studied eleven normotensive and 24 untreated hypertensive elderly subjects (mean age 75.7 years, range 63-85) and compared the results of the sweatspot test to a young control group (n = 11, mean age 32.0 years, range 25-41), and to a standard battery of cardiovascular autonomic function tests. The median sweatspot score was significantly lower in the elderly compared with young subjects (1.9 vs. 12.0, p < 0.0001) although there was no difference between elderly normotensive and hypertensive subjects (1.6 vs. 2.4, p = 0.8). No correlation was demonstrated between the median sweatspot score and the number of abnormal cardiovascular tests. The sweatspot test was grossly abnormal in all elderly subjects and was not correlated to changes in cardiovascular autonomic function. Its diagnostic use in the elderly is therefore of very limited value.

Acetylcholine↗

PubMed2000

[Postural orthostatic tachycardia syndrome (POTS): etiology, diagnosis and therapy].

BACKGROUND: Since the renaissance of tilt table testing in clinical cardiology some 15 years ago, the syndromes of autonomic dysfunction with orthostatic intolerance underwent improved differentiation and classification. In the present review a variant of autonomic dysfunction with orthostatic intolerance--POTS (postural orthostatic tachycardia syndrome)--will be discussed. DIAGNOSIS AND TREATMENT: The affected patients present with orthostatic intolerance, postural tachycardia, exercise intolerance, fatigue, dizziness and in some cases with other dysautonomic symptoms such as gastrointestinal or sudomotor dysfunction. Together with the clinical history, tilt table testing is the cornerstone of diagnostic evaluation by which the syndrome can be distinguished from typical neurocardiogenic disorders. POTS is characterized by different subtypes; accordingly, therapy for relief of symptoms is variable and includes beta blockers for patients with the hyperadrenergic type and alphamimetics for those with partial dysautonomia. CONCLUSION: Although it is now possible to differ POTS from other forms of autonomic dysfunction, further research is warranted to clarify the pathophysiology of this syndrome and its subtypes and to improve therapeutic interventions.

Adrenergic Agents↗

PubMed1998

Longitudinal follow-up of cardiovascular reflex tests in multiple sclerosis.

Several studies have shown various degrees of autonomic dysfunction in patients with multiple sclerosis. Longitudinal follow-up studies are remarkably scarce up to now. We assessed autonomic dysfunction twice with an interval of 1 year in 20 relapsing remitting and 26 secondary progressive MS-patients. Autonomic function was assessed by the heart rate response during deep breathing, standing up and Valsalva manoeuvre. Only the maximum change in heart rate after standing up (in ms and beats/min) and the Max/Min ratio after standing up showed significant worsening over 1 year. The changes in EDSS scores also documented gradual deterioration of the neurological condition over the study period. We conclude that there is progression of autonomic dysfunction in MS over 1 year and that this could correlate with progression in clinical disability.

Adult↗

PubMed2001

Familial association of autonomic and gastrointestinal symptoms.

Autonomic dysfunction occurs in the adult population with irritable bowel syndrome, but this association is not recognized in children. A mother and son with functional abdominal pain unresponsive to conventional treatment had complete resolution of symptoms with treatment directed at the autonomic dysfunction identified by testing. The authors recommend autonomic testing in patients with functional abdominal pain and suggest that autonomic dysfunction plays a direct and intrinsic role in the mechanism of these disorders and their symptoms.

Adrenergic beta-Antagonists↗

PubMed1996

No change in automatic function tests during uncomplicated haemodialysis.

Uraemic autonomic dysfunction is reckoned to participate in dialysis hypotension, but a clear relationship has not been established. However, autonomic function is usually tested at rest, and possibly autonomic dysfunction arises or worsens during dialysis. We therefore performed easily repeatable tests of efferent sympathetic function, that is static exercise test and parasympathetic function, that is heart rate variability during Valsalva manoeuvre and deep breathing, at successive stages of a standard haemodialysis session; before dialysis, 20 min after dialysis without ultrafiltration, after 3 h of dialysis combined with ultrafiltration, and 20 min after dialysis. Studies were performed in 22 patients on chronic haemodialysis on a cuprophane dialyser. The mean ultrafiltration volume was 2.2 +/- 0.61. We found that blood pressure elevation upon static exercise, and heart rate variability during Valsalva or deep breathing test remained unaltered at the various stages of dialysis. On past performance the patients were divided into hypotension prone (n = 6) or resistant (n = 16). Hypotension prone patients showed a greater blood pressure drop during dialysis, but also showed an appropriately enhanced heart rate acceleration. The occurrence of autonomic dysfunction was not elevated in this group, nor did such dysfunction develop along dialysis. Predialysis parasympathetic function tests were abnormal in 10 patients. These patients also showed an augmented intradialytic blood pressure decrease, but no enhanced acceleration in heart rate. Their parasympathetic dysfunction did not worsen during dialysis. Based upon the predialysis exercise test, low responding patients (blood pressure increase 5 +/- 2 mmHg, n = 11) were distinguished. These subjects were not characterized by a greater blood pressure decrease or different heart rate acceleration. Generally, the responses upon exercise, whether low or high, remained unaltered during dialysis. we conclude that haemodialysis has no systematic effect on autonomic function. Hypotension-prone patients are not distinguished by a disturbed predialytic or intradialytic autonomic blood pressure control.

Adult↗

PubMed1992

[Carcinomatous autonomic neuropathy and the autoantibodies in paraneoplastic neuropathy].

Carcinomatous autonomic neuropathy is a syndrome of autonomic dysfunction associated with malignant neoplasm. It is most often associated with small-cell lung cancer. Auto-immune mechanism is suspected to underlie this syndrome. Among the symptoms of autonomic dysfunction, intestinal pseudo-obstruction is most frequently seen. The autonomic dysfunction often precedes the discovery of the cancer. Several autoantibodies have been reported in paraneoplastic neuropathies. Anti-Hu antibody, which was originally reported in paraneoplastic sensory neuronopathy, has also been detected in some cases with autonomic failure. Anticarbohydrate antibody activity has been frequently shown in IgM M-proteins associated with peripheral neuropathies. These include anti-MAG, Po, and sulphated glucuronyl glycolipids in demyelinating neuropathy and anti-GM1 in motor dominant neuropathy or motor neuron disease. Further investigation should reveal more glycoconjugate antigens as targets of possible auto-immune attack in paraneoplastic neuropathies.

Autoimmune Diseases↗

PubMed1988

Comparative analysis of autonomic and somatic dysfunction in chronic uraemia.

The relationship between autonomic dysfunction and peripheral somatic neuropathy was investigated in uraemics. The battery of autonomic tests included R-R interval variation test, deep breathing, Valsalva manoeuvre, heart rate and blood pressure responses to standing, and sustained handgrip. Maximum conduction velocity along sensory and motor fibres of the posterior tibial nerve was measured. An impairment of parasympathetic reflexes was more frequent than a sympathetic damage, but with no relationship to the degree of electrophysiological disturbances. Cardiovascular autonomic dysfunction and somatic neuropathy in uraemia result to be two different entities in incidence and perhaps in pathogenesis.

Adult↗

PubMedDate not supplied

[Prevention of myopia in children].

Eye diseases rank third in the structure of morbidity among children aged 0 to 17 years. Acquired myopathy is the leading abnormality in the structure of morbidity, with diminished vision being in 28% of preschool children and in every two school graduates. Myopia is attended by the signs of systemic connective tissue dysplasia and impaired circulation due to autonomic dysfunction. Early diagnosis and correction of autonomic dysfunction is the basic line of the prevention and treatment of school myopia. Treatment of children can be organized in the medical room of a school. Along with general health-improving measures, physiotherapetic procedures, such as lens exercises, curative gymnastics, massage, and gentle manual therapy procedures should be used in the multimodality treatment of children with myopia. Autonomic tone can be regulated through the visual analyzer by pulse photostimulation on a spectral ophthalmologic apparatus (an up-to-date ACO-05 software model ("DEST", Cheboksary). Moreover, circulation improves, eye muscles become stronger, visual reflexes restore, and vision improves. A school oculist's room may be used as a new health-improving form in children with myopia. It should be set up in every school since the high efficiency of treatment for accommodation spasm is an important argument of the prevention of myopia, promotes a greater coverage of children with early myopia by means of therapeutic measures, as well as timely and contemporary prevention of progressive myopathy.

Child↗

PubMed1999

Autonomic nervous system disorders in stroke.

Disturbances of the autonomic nervous system are common in patients with various cerebrovascular diseases. They are attributed to damage of the central autonomic network, particularly in the frontoparietal cortical areas and in the brain stem, or to a disruption of the autonomic pathways descending from the hypothalamus via the mesencephalon, pons, and medulla to the spinal cord. The most common clinical problems include abnormalities in heart rate and blood pressure regulation, reflecting cardiovascular autonomic dysfunction, and asymmetric sweating with cold hemiplegic limbs, reflecting changes in the sudomotor and vasomotor regulatory systems. Bladder and bowel dysfunction and impotence are also frequent complaints after stroke, but the present knowledge concerning their prevalence and clinical significance is still limited. Cardiovascular autonomic dysfunction, which is mainly related to increased sympathetic activity, is most evident in the acute phase of stroke, whereas other autonomic disorders, such as abnormal sweating, are long-standing or even irreversible. In addition to the well-established sympathetic hyperfunction, abnormalities of the parasympathetic nervous system may also contribute to the autonomic imbalance after stroke. Reliable recognition of autonomic dysfunction using quantitative analysis methods is important, because these disturbances are not only subjectively disabling and uncomfortable, but they may also be prognostically unfavorable. Moreover, quantitative measurements also form the ground for successive treatment of various stroke-related autonomic disorders.

Autonomic Nervous System Diseases↗