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Ocular autonomic dysfunction and intraocular pressure in leprosy.

We examined 241 leprosy patients and 135 age-matched healthy controls in central South Korea, measuring intraocular pressure in the supine and the upright positions and measuring the size of the pupils in darkness as an indication of ocular autonomic dysfunction. The mean intraocular pressure was significantly lower in the patients and the mean size of pupils was significantly smaller in the patients than in the controls. However, there was no correlation between pupil size and intraocular pressure in our patients. Our findings show that leprosy patients have ocular autonomic dysfunction, but do not support previous speculation that this dysfunction is the primary cause for low intraocular pressure in leprosy.

Adult

Cardiac autonomic dysfunction and neuroganglionitis in a rat model of chronic Chagas' disease.

OBJECTIVE: The aim was to evaluate whether the cardiac parasympathetic function in a rat model of chronic Chagas' disease is impaired as in the human disease, and to correlate the functional state to histopathology of the intrinsic autonomic innervation of heart. METHODS: 70 male Wistar rats 8 months infected with strains Y (n = 22), São Felipe (n = 18), and Colombia (n = 30) of Trypanosoma cruzi, were compared with 20 age and sex matched non-infected controls. Baroreflex bradycardia was quantified after multiple bolus injections of phenylephrine (3 to 12 micrograms). For each rat studied a mean was obtained of the absolute and relative (delta %) ratio (index) between the maximum heart rate decrease and the maximum systolic blood pressure increase. RESULTS: For the relative index the means were smaller (p less than 0.05) in the Y [-0.52(SD 0.19)%], São Felipe [-0.45(0.28)%], and Colombia [-0.53(0.21%)] subgroups, as well as in the pooled chagasic group [-0.51(0.22)%], than in the control group [-0.64(0.13)%]. In 32% (7/22), 33% (6/18), and 20% (6/30) of rats infected with Y, São Felipe, and Colombia strains, respectively, and in 27% (19/70) of the pooled group rats, the index exceeded the control group mean by -2 SD. After atropinisation, a similar pronounced reduction (p less than 0.01) in the index was observed in all groups [-84(28)% to -95(17)%]; however, rats with depressed bradycardia showed a smaller (p less than 0.05) reduction in the relative index than control rats, at -70(34) v -92(16%). Inflammatory and degenerative lesions of the intrinsic cardiac innervation were observed in 87% of the rats with autonomic dysfunction. Rats with the lesions showed a mean relative index that was smaller than those without lesions, at -0.44(0.23) v -0.64(0.20)% (p less than 0.01), and also smaller than in the controls. CONCLUSIONS: Cardiac autonomic dysfunction expressed by reduced baroreflex bradycardia was detected in rats chronically infected with T cruzi, as in human Chagas' disease. The disturbance, shown for the first time in an animal model of chagasic infection, resulted primarily from impaired efferent parasympathetic activity caused by intrinsic neuroganglionar lesions.

Animals

Autonomic dysfunction and silent myocardial ischaemia on exercise testing in diabetes mellitus.

The incidence and mechanism of painless myocardial ischaemia on exercise testing in diabetic patients is not clear. Therefore, two studies were performed. Retrospectively, all exercise tests carried out in our hospital during the past 5 years were reviewed for silent ischaemia. Prospectively, diabetic patients with known or suspected coronary artery disease underwent autonomic function testing and a second exercise test. Of 1653 exercise tests reviewed, 247 were positive (ST depression greater than 0.1 mV). Of the 29 diabetic patients with positive tests 20 (69%) had painless ST depression, compared with 77 (35%) of the 218 non-diabetic patients (p less than 0.001). The diabetic patients with painful and painless ST depression were comparable for age, sex, therapy, but the 20 with no pain on exercise testing had a longer duration of diabetes and a higher incidence of microvascular complications than the 9 with pain (70 vs 22%, p less than 0.05). In the prospective study, 12 of 30 diabetic patients with positive exercise tests had pain in association with ST depression and 18 had no pain. Six patients had mild and 12 severe autonomic neuropathy on formal testing. Twelve had no autonomic dysfunction. Eleven (92%) of 12 patients with severe neuropathy had painless ST depression, compared with 7 (39%) of 18 without severe neuropathy (p less than 0.01). Thus, silent myocardial ischaemia on exercise testing is common among patients with diabetes mellitus and is associated with severe autonomic dysfunction.

Aged

Increased prevalence of proliferative retinopathy and cardiovascular autonomic dysfunction in IDDM patients with proteinuria.

The purpose of the present cross-sectional clinical study was to evaluate the prevalence of retinopathy in Type 1 diabetic patients without nephropathy and with different degrees of nephropathy. In addition we investigated the association between retinopathy, nephropathy, and other variables, and studied the importance of cardiovascular autonomic dysfunction to these conditions. 76 Type 1 diabetic patients were investigated. All patients were initially selected on the basis of body weight, and 47 proteinuric patients were further selected for age, diabetes duration and the duration of insulin treatment (see Table 1). Proteinuric diabetic patients were categorized by degree of nephropathy, i.e. for incipient nephropathy (proteinuria of less than 0.5 g/day), for overt nephropathy (proteinuria of more than 0.5 g/day), and for renal failure (serum creatinine of more than 103 mumol/l). Retinopathy was assessed by ophthalmoscopy. Cardiovascular autonomic dysfunction (CAD) was assessed by heart rate variations, 30:15 ratios, the Valsalva maneuver, and systolic blood pressure fall upon standing. Our findings revealed increased prevalence of retinopathy in patients with more advanced stages of nephropathy. CAD abnormalities exhibited increased prevalence among proteinuric patients. Our data clearly revealed differences between proteinuric and non-proteinuric patients. In both proteinuric and non-proteinuric patients there were found correlations of retinopathy with diabetes duration, and only in proteinurics was retinopathy correlated with kidney function, systolic blood pressure and CAD findings. In patients in identical stages of nephropathy, increased prevalence of CAD abnormalities was shown in patients suffering from proliferative retinopathy. Thus our data suggest that CAD abnormalities might be related in some way to both the proliferative retinopathy and to diabetic nephropathy.

Adult

Autonomic dysfunction in men with Parkinson's disease.

Forty-eight men with Parkinson's disease (PD) were interviewed utilizing a questionnaire which evaluated autonomic function. The study population included PD patients (mean age: 65.8 years, mean duration of PD: 8 years) and 32 elderly healthy nonparkinsonian males (mean age: 70.4 years). We found a significantly higher prevalence of the following symptoms of autonomic dysfunction in the parkinsonian patients: erectile dysfunction (60.4 vs. 37.5%), sensation of incomplete bladder emptying (41.6 vs. 15.6%), urgency (45.8 vs. 3.125%), constipation (43.9 vs. 6.25%), dysphagia (22.9 vs. 6.25%) and orthostatic dizziness (21.95 vs. 0%). Eighty-nine percent of parkinsonian patients had at least one of these autonomic symptoms, compared to 43% of control subjects (p less than 0.05). This study is the first comprehensive survey of autonomic symptomatology in PD compared to elderly healthy controls and confirms that autonomic nervous system dysfunction is a pervasive problem in PD. Erectile dysfunction is a significant problem in this patient group and contributes to deterioration in the quality of life.

Aged

Improved technique for testing autonomic dysfunction: evaluation of transient behaviour of the autonomic response.

The transient behaviour of the autonomic response has been studied by means of a reactometer incorporating self-balancing of the electrodermal impedance. This instrument has been used for the indirect measurement of certain parameters associated with the autonomic response detected as skin electrical resistance relative variation (SERV) and capacitance (SECV). Transient signals of the electrodermal impedance response were obtained online by differentiating the analogue output of the impedance reactometer: d(SERV)/dt and d(SECV)/dt. We describe here how the use of the transient signals of the electrodermal impedance response can improve the accuracy and reduce variability and dispersion of the results and how autonomic conduction velocities (ACV) can be indirectly measured.

Autonomic Nervous System

Autonomic dysfunction at different ambient temperatures in infants at risk of sudden infant death syndrome.

Autonomic function was assessed by measuring the heart rate and blood pressure responses to a change from the horizontal to upright posture at various ambient temperatures in four groups of infants aged 8-12 weeks: 30 infants who had suffered a well-defined unexplained apparent life-threatening event (ALTE); 8 infants who had suffered a cyanotic attack; 24 healthy infants with a sibling who had died from sudden infant death syndrome (SIDS); and 17 healthy infants. Autonomic dysfunction was uncommon in the control group; no infant showed an abnormal heart rate response to postural change (R to R interval maximum/minimum ratio less than 1.0) and a postural fall in blood pressure of greater than 10% occurred in only 1 infant. In contrast, in the ALTE group 9 of 26, 9 of 30, and 4 of 22 infants showed an abnormal heart rate response and 20 of 26, 14 of 30, and 10 of 22 a greater than 10% fall in blood pressure on postural change at 20 degrees C, 25 degrees C, and 30 degrees C, respectively. 1 ALTE infant died of SIDS 14 h after showing an RR max/min ratio of 0.8 and a postural fall in blood pressure of 11% and 14% at 20 degrees C and 30 degrees C. Autonomic function testing should become part of the clinical evaluation of infants at high risk of a sudden unexpected death.

Autonomic Nervous System Diseases

[Autonomic dysfunction of central nervous system disorders].

Central nervous system disorders, such as cerebrovascular or spinal cord lesions often cause dysfunctions of the autonomic nervous system. In most cases of acute cerebrovascular accidents, blood pressure is transiently elevated. Some patients, especially with pontine or thalamic hemorrhage, suffer from extremely high fever. In patients with large lesions in the cerebral hemisphere or lesions in the brainstem, cardiopulmonary state may be affected. In spite of absence of acute myocardial infarction, electrocardiogram may show ST-T changes resembling acute myocardial infarction. Cheyne-Stokes respiration or sleep apnea can occur. Lesions in the medulla oblongata cause dysfunctions of automatic respiration. Patients with large cerebrovascular lesions in the unilateral hemisphere often show transient hyperhidrosis on the contralateral side. Prognosis of patients with these autonomic failures is poor. In patients with spinal shock, blood pressure and heart rate are reduced. In chronic stage, autonomic hyperreflexia, such as attacks of episodic hypertension can occur. Lesions in the high cervical cord often bring nonsymptomatic perforating gastric ulcer.

Autonomic Nervous System Diseases

Adult onset autonomic dysfunction coexistent with familial dysautonomia in a consanguineous family.

A consanguineous family is described in which autonomic dysfunction developed in the father during adult life while the son had familial dysautonomia at birth. The father's condition is felt to be secondary to olivopontocerebellar atrophy. The concurrence in this family of an adult and a childhood form of dysautonomia may be an expression of the same genetic defect at different stages of development.

Adult

The Riley-Day syndrome. Familial dysautonomy, central autonomic dysfunction.

The Riley-Day syndrome is characterized by a dysfunction of the autonomous nervous system, sensory disturbances, neurological disorders, psychical anomalies and important ophthalmological symptoms, such as absence of tears, corneal anaesthesia, keratinized conjunctiva and cornea; myosis after instillation of methacholine. The diagnosis is based on the absence of fungiform papillae of the tongue and the absence of reaction after intradermic injection of histamine. The inheritance is autosomal recessive. The disease results probably from an enzymatic insufficiency.

Child, Preschool

Autonomic dysfunction in systemic sclerosis: sympathetic overactivity and instability.

PURPOSE: This study was designed to assess the prevalence and nature of autonomic dysfunction (AD) in 34 patients with systemic sclerosis (SSc). PATIENTS AND METHODS: Patients were questioned for current symptoms possibly related to AD. Five noninvasive cardiovascular autonomic function tests and sequential plasma catecholamine estimations at rest, during standing, and during sustained handgrip were performed. Seven patients with manometrically documented esophageal involvement and high resting plasma adrenaline levels were treated with clonidine (75 to 375 micrograms/d). One month later, resting plasma catecholamine estimations and esophageal motility studies were repeated. RESULTS: Autonomic testing revealed AD in each patient, while symptoms were experienced by 33 of them. Findings on two of the three heart rate tests and both blood pressure tests were significantly impaired as compared with those in 25 matched control subjects. Mean resting plasma adrenaline levels were 18 times higher than in 10 matched controls (p less than 0.001). Plasma catecholamine (adrenaline, noradrenaline, and dopamine) concentrations and mean arterial blood pressures fluctuated inappropriately during standing and sustained handgrip in 28 (82%) of the patients. The presence of headaches correlated significantly with sympathetic overactivity and instability (p less than 0.05). Resting plasma adrenaline concentrations correlated inversely with disease duration (p less than 0.05). Significant suppression of sympathetic overactivity and increases in resting lower esophageal sphincter pressures were observed in the seven patients treated with clonidine. CONCLUSION: AD is extremely common in SSc. It is characterized by parasympathetic impairment and marked sympathetic overactivity, particularly in early disease. The potential role of AD in the pathogenesis of SSc deserves further study.

Adult

Oesophageal transit in patients with autonomic dysfunction. The effect of treatment with fludrocortisone.

Oesophageal function was examined by radionuclide transit measurements in 15 patients with severe autonomic deficiency and orthostatic hypothension and 23 healthy volunteers. Seven of the patients were re-examined after treatment for 3 weeks with fludrocortisone acetate (Florinef). Six patients and five control subjects were evaluated before and after i.v. administration of atropine. The mean transit time (MTT) was prolonged (P less than 0.007) and the residual activity increased (P = 0.038) in the patients compared with the control group. Prolonged MTT was associated with oesophageal symptoms. Treatment of orthostatic hypotension with fludrocortisone acetate significantly reduced MTT. Atropine increased MTT and residual activity. The increase in heart rate after atropine was correlated in the patients with MTT before treatment. The results demonstrate the frequent presence of impaired oesophageal function in patients with severe autonomic dysfunction, irrespective of aetiology. The impairment seems to be closely related to parasympathetic insufficiency. The improvement after fludrocortisone may suggest an influence of ion balance on oesophageal function in these patients.

Adult

Autonomic dysfunction in central nervous system disorders.

Dysautonomic symptoms are associated with many disorders of the central nervous system, in some of which the autonomic dysfunction is particularly conspicuous or the major cause of disability. New neuroimaging procedures and microneurographic techniques have helped to clarify the underlying pathophysiology and to distinguish or, classify disorders that are clinically similar. Recent studies also suggest that the autonomic nervous system is involved more frequently or extensively than previously thought in certain neurological conditions such as multiple sclerosis or human immunodeficiency virus (HIV) infection, and have helped to define the nature of its involvement in other disorders.

Autonomic Nervous System

Autonomic dysfunction in alcoholic cirrhosis: relationship to indicators of synthetic activation and the occurrence of renal sodium retention.

We investigated the occurrence of alcoholic autonomic dysfunction in patients with alcoholic cirrhosis in order to define its prevalence and relationship to renal sodium retention. Forty-seven alcoholics and 16 age-matched normal subjects were evaluated. Thirty-seven patients had liver disease (13 with and 24 without ascites), and 10 patients had normal hepatic function. Autonomic nervous system function was ascertained by skin sudomotor responses and the response of blood pressure and plasma norepinephrine concentration to upright tilt (sympathetic nervous system function), and by heart rate responses to deep breathing, Valsalva maneuver, and upright tilt (parasympathetic and sympathetic nervous system function). Heart rate responses to deep breathing and Valsalva maneuver were diminished, and skin sudomotor responses were significantly worse, in alcoholics than in control subjects. Alcoholic patients also had significantly lower supine mean arterial pressure (93 +/- 10 vs. 116 +/- 8 mm Hg, p less than or equal to 0.0001), and significantly greater increases in arterial pressure during passive upright tilt, than control subjects (mean increase 6.5 +/- 6.6 vs. 0.1 +/- 1.6 mm Hg, p = 0.0003). All of these findings were present to similar degrees in patients with and without liver disease and in cirrhotic patients with and without ascites. Supine heart rates, however, differed among the groups evaluated. Heart rate was significantly greater in patients with cirrhosis than in alcoholic patients without liver disease (83 +/- 11 vs. 71 +/- 13 bpm, p = 0.006), and in patients with ascites than in patients without ascites (88 +/- 12 vs. 80 +/- 10 bpm, p = 0.04). Plasma norepinephrine concentration was elevated in most patients with cirrhosis and was significantly higher in patients with ascites than in patients without ascites (789 +/- 238 vs. 388 +/- 185 pg/ml, p less than 0.0001; nl range: 65-320 pg/ml). Autonomic nervous system function is similarly impaired in alcoholics with and without liver disease. Patients with cirrhosis also have increased heart rate and elevated plasma norepinephrine concentration, abnormalities that are most pronounced in patients with sodium retention. Their is uncertainty as to the stimulus for norepinephrine release, and its source, in these patients. However, the similarity of supine blood pressure in patients with and without ascites and the occurrence of orthostatic hypertension rather than orthostatic hypotension following upright tilt suggest that arterial underfilling is not responsible.

Ascites

Correlation between oesophageal dysmotility and cardiovascular autonomic dysfunction in diabetic patients without gastrointestinal symptoms of autonomic neuropathy.

The vagal function was assessed by oesophageal scintigraphy and cardiovascular autonomic function tests in 65 diabetic patients without gastrointestinal symptoms of autonomic neuropathy and in 20 control subjects. Oesophageal radioisotope transit time was abnormal in 32% of diabetics. Values of cardiovascular function tests were normal in 34% of diabetics while definitive and early signs of cardiac autonomic neuropathy were found in 34% and 32% of diabetics, respectively. The results of oesophageal scintigraphy and cardiovascular function tests were concordant only in 54% of diabetics. Simultaneous impairment of oesophageal motility and cardiovascular (vagal) reflexes could be frequently but not uniformly observed in diabetics. Thus, vagal innervation of different organs (oesophagus and heart) might be affected to different degrees in diabetic patients.

Diabetes Mellitus, Type 1

Carbamazepine in Fabry's disease: effective analgesia with dose-dependent exacerbation of autonomic dysfunction.

Seven patients with Fabry's disease and severe pain received carbamazepine (CMZ). Five of 7 patients had moderate to complete relief based upon self-assessment of pain levels. Preexisting autonomic dysfunction was exacerbated by CMZ in 2. Complications encountered were ileus, urinary retention, and gastrointestinal disturbance. Although CMZ was useful in treatment of pain, caution should be employed in this disease.

Adult

Cardiovascular reflexes and autonomic dysfunction in Parkinson's disease.

Cardiovascular reflexes were analysed in a group of 20 patients suffering from Parkinson's disease and in 12 age-matched healthy subjects, in order to ascertain the incidence and degree of autonomic dysfunction. The following were measured: heart rate variation during normal breathing, postural change (30/15 ratio) and during the Valsalva manoeuvre: blood pressure variation after standing. These measurements were taken at least 12 h after therapy had been withdrawn and were repeated after therapy had been resumed. Significant changes in the different heart rate variation indices were found in the parkinsonian patients which correlated with the duration and severity of the extrapyramidal symptomatology. After standing the patients showed a significant drop in blood pressure, when compared respectively with their base values and with the response in controls. Anticholinergic drugs had no significant effect on the heart rate variation indices, whereas antiparkinsonian therapy seems to have contributed to the drop in blood pressure after standing.

Adult