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Query: UMLS:C0015672 (fatigue)
 51,768 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Head upright tilt table testing has emerged as an accepted modality for identifying an individual's predisposition to episodes of autonomically mediated hypotension and bradycardia that are sufficiently profound so that transient loss of consciousness ensues (neurocardiogenic syncope). However it has also become apparent that less dramatic falls in blood pressure, while not sufficient to cause full syncope, may produce symptoms such as near syncope, vertigo, dizziness, and TIA-like episodes. We have identified a subgroup of individuals with a mild form of autonomic dysfunction with symptoms of postural tachycardia and lightheadedness, disabling fatigue, exercise intolerance, dizziness, and near syncope. During baseline tilt table testing these patients demonstrated a heart rate increase of > or = 30 beats/min (or a maximum heart rate of 120 beats/min) within the first 10 minutes upright (unassociated with profound hypotension), which reproduced their symptom complex. In addition these patients exhibit an exaggerated response to isoproterenol infusions. Similar observations have been made by others who have dubbed this entity the Postural Orthostatic Tachycardia Syndrome (POTS). We conclude that POTS represents a mild (and potentially treatable) from of autonomic dysfunction that can be readily diagnosed during head upright tilt table testing.
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PMID:The postural orthostatic tachycardia syndrome: a neurocardiogenic variant identified during head-up tilt table testing. 930 45

Three cases cardiac death in young male athletes are described, and the medical management outlined. On the basis of extensive data available in published reports, it is argued that the risk group can be more clearly distinguished clinically than is usual today. It is stressed that athletic young adults consulting for dyspnoea, cardiac arrhythmia, syncope, tiredness, or nonspecific postinfectious symptoms, may have serious cardiac disease. It is concluded that, to prevent sudden cardiac death, ECG examination should be performed without delay, followed in the case of abnormal findings by extended cardiological investigation.
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PMID:[Sudden death among young people. ECG and selective investigation of non-specific postinfectious problems may prevent fatal outcome]. 944 36

To examine the literature on chronic fatigue syndrome (CFS), especially as it relates to cognitive deficits and exercise, more than 200 articles related to CFS were selected from computer-based research as well as pertinent articles noted in the references of individual articles. All were relevant articles on CFS, although articles in a foreign language were excluded. CFS is a controversial diagnosis of exclusion, but certain subgroups do appear to exist. It may represent multiple diseases or multiple stages of the same disease. Although cognitive deficits are commonly reported, the measured impairments are relatively subtle and are in the area of complex information processing speed, or efficiency. Magnetic resonance imaging, single-photon emission computer tomography, and neuroendocrine studies present preliminary evidence suggestive of the cerebral involvement primarily in the white matter. The weakness and fatigue may be the result of alterations in the central nervous system, not in the peripheral muscles. However, it is hard to separate the documented weakness and endurance deficits from deconditioning. Autonomic symptoms such as orthostatic intolerance and a predisposition to neurally mediated syncope may be explained by cardiovascular deconditioning, a postviral idiopathic autonomic neuropathy, or both. The review points out the need for more carefully designed studies of CFS that focus on the relationship between neuropathology, psychopathology and neuropsychologic functioning. The role of exercise as a stimulus for exacerbation or in treatment needs to be further studied using clear diagnostic criteria as well as control groups that carefully match the activity level.
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PMID:Chronic fatigue syndrome: a literature review from a physiatric perspective. 955 19

This study examined the efficacy of glycerol and water hyperhydration (1 h before exercise) on tolerance and cardiovascular strain during uncompensable exercise-heat stress. The approach was to determine whether 1-h preexercise hyperhydration (29.1 ml H2O/kg lean body mass with or without 1.2 g/kg lean body mass of glycerol) provided a physiological advantage over euhydration. Eight heat-acclimated men completed three trials (control euhydration before exercise, and glycerol and water hyperhydrations) consisting of treadmill exercise-heat stress (ratio of evaporative heat loss required to maximal capacity of climate = 416). During exercise ( approximately 55% maximal O2 uptake), there was no difference between glycerol and water hyperhydration methods for increasing (P < 0.05) total body water. Glycerol hyperhydration endurance time (33. 8 +/- 3.0 min) was longer (P < 0.05) than for control (29.5 +/- 3.5 min), but was not different (P > 0.05) from that of water hyperhydration (31.3 +/- 3.1 min). Hyperhydration did not alter (P > 0.05) core temperature, whole body sweating rate, cardiac output, blood pressure, total peripheral resistance, or core temperature tolerance. Exhaustion from heat strain occurred at similar core and skin temperatures and heart rates in each trial. Symptoms at exhaustion included syncope and ataxia, fatigue, dyspnea, and muscle cramps (n = 11, 10, 2, and 1 cases, respectively). We conclude that 1-h preexercise glycerol hyperhydration provides no meaningful physiological advantage over water hyperhydration and that hyperhydration per se only provides the advantage (over euhydration) of delaying hypohydration during uncompensble exercise-heat stress.
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PMID:Hyperhydration: tolerance and cardiovascular effects during uncompensable exercise-heat stress. 960 77

Past studies have shown that severe fatigue was the presenting symptom in six of seven patients with delayed orthostatic hypotension and that tilt table-induced hypotension was found in 22 of 23 patients with the chronic fatigue syndrome. We have determined the prevalence of fatigue, volunteered in response to a nonspecific pre-examination questionnaire used in 431 patients, each subsequently diagnosed as having one of eight neurological or endocrine disorders. The results show that fatigue is a very common symptom in patients with delayed orthostatic hypotension (n = 21), as well as both primary (n = 30) and secondary (n = 106) hypocortisolism: 70-83% in all groups. In contrast, fatigue was an uncommon complaint in patients with multiple system atrophy (MSA) (n = 30), pituitary disorders without hypocortisolism (n = 106) or idiopathic hirsutism (n = 96): 7-33% in all groups, and was intermediate in prevalence in patients with acute hyperadrenergic orthostatic hypotension (n = 32): 41%. It is concluded that fatigue commonly results from delayed orthostatic hypotension and all forms of hypocortisolism but is less common in patients with acute orthostatic hypotension, both idiopathic and due to MSA, which more commonly present with lightheadedness or syncope.
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PMID:The role of delayed orthostatic hypotension in the pathogenesis of chronic fatigue. 961 2

Menorrhagia--menstrual periods lasting longer than 7 days and totaling blood losses greater than 80mL--affects 9%-14% of otherwise healthy women, and it can signal cancer, an endocrinologic disorder, or gynecologic disease. Blood loss can be high enough to result in anemia, fatigue, and syncope. Most often, abnormal uterine bleeding such as menorrhagia involves a disruption in the hypothalamic-pituitary axis, the ovary, and/or the uterus. Other identified causes include medications (especially psychotropics) that cross the blood-brain barrier; chronic diseases such as cancer, diabetes, and liver and kidney dysfunction; endocrine disorders, perimenopausal anovulation, polycystic ovary disease, pituitary tumors, and abnormal estrogen cycling caused by morbid obesity; and anatomic abnormalities of the uterus. Routine tests include hematocrit or hemoglobin to detect and evaluate anemia, thyroid stimulating hormone (TSH) level to evaluate thyroid function as a possible cause, and a pregnancy test to rule out an incomplete, spontaneous abortion as a cause. A Pap test is recommended to screen for dysplasia that can suggest a gynecologic cancer cause. Additional screening for endocrine disorders that may be causing menorrhagia include tests of thyroid, liver, and kidney function, and tests of follicle stimulating hormone (FSH), prolactin, and cortisol levels. Treatment can be medical or surgical. Medical treatment includes prostaglandin inhibitors, specifically nonsteroidal antiinflammatory drugs (NSAIDs), and hormonal therapy with estrogen, progesterone, gonadotropin-releasing hormone agonists, or oral contraceptives such as medroxyprogesterone (Depo-Provera). Surgical treatment includes hysteroscopic endometrial ablation by physical agents, laser electrodiathermy, and "roller ball," or surgical, resection. Hysterectomy is the treatment of last resort.
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PMID:Treatment Decisions in the Management of Menorrhagia. 974 72

Heat-related illnesses cause 240 deaths annually. Although common in athletes, heat-related illnesses also affect the elderly, persons with predisposing medical conditions and those taking a variety of medications. Symptoms range from mild weakness, dizziness and fatigue in cases of heat edema, to syncope, exhaustion and multisystem complications, including coma and death, in cases of heat stroke. Milder heat-related symptoms can be treated with hydration, rest and removal from the hot environment. Heat stroke, a life-threatening problem, must be treated emergently. Prompt recognition is critical since rapid cooling is the cornerstone of treatment and must not be delayed. Fluid resuscitation with dextrose and normal or half-normal saline is also important. These therapies should be instituted while the patient is being stabilized. Heat illness may be prevented by recognizing which individuals are at risk, using appropriate hydration and paying attention to acclimatization and environmental conditions. Preventive care should include drinking plenty of fluids before, during and after activities, gradually increasing the time spent working in the heat and avoiding exertion during the hottest part of the day.
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PMID:Heat-related illnesses. 975 May 42

A normal, uncomplicated pregnancy causes many physiologic cardiovascular changes and symptoms. For example, maternal blood volume, heart rate, and cardiac output increase, and fatigue, orthopnea, and presyncope often occur. In general, these findings are innocuous. Physicians need to recognize those that are not typically associated with pregnancy, such as diastolic murmurs, paroxysmal nocturnal dyspnea, and syncope. Diagnostic evaluation of pregnant women must be approached cautiously to avoid risk to the fetus. Methods using ionizing radiation should be avoided whenever possible. Hypertension, one of the most common complications of pregnancy, may be transient and benign, or it may be chronic or gestational. Early recognition and intervention are beneficial to both the mother and the child.
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PMID:Heart disease during pregnancy. Which cardiovascular changes are normal or transient? 979 64

alpha-Agonists are a relatively old class of medications, the topical use of which lowers eye pressure. Clonidine was introduced for this use in 1966, brimonidine in 1974, and apraclonidine in 1978. Initial short-term attempts to use clonidine were complicated by problems with systemic hypotension. Apraclonidine is more polar and less lipophilic than clonidine. This probably allows less penetration into both the posterior segment of the eye and systemic circulation, allowing for an excellent therapeutic index. The prophylactic use of apraclonidine (1% and 0.5%) has dramatically changed the safety profile for many anterior segment laser procedures, cataract surgery, and vitrectomy. The role of alpha-agonists in the chronic treatment of glaucoma is still uncertain. Potential benefits of additional lowering of intraocular pressure must be weighed against the following potential disadvantages: tachyphalaxsis, posterior segment vasoconstriction, psychologic depression and fatigue, syncope and systemic hypotension, and a topical allergy-like syndrome.
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PMID:The role of alpha-agonists in glaucoma therapy. 1016 56

The symptoms caused by or relating to orthostatic hypotension (over 20 mmHg systolic blood pressure) were evaluated using a questionnaire in 72 patients with primary chronic autonomic failure, 32 of whom had pure autonomic failure (PAF, and 40 multiple system atrophy (MSA). The most common posturally related symptoms were dizziness (84% PAF, 83% MSA), syncope (91% PAF, 45% MSA), visual disturbances (75% PAF, 53% MSA) and suboccipital/paracervical 'coat-hanger' neck pain (8 l% PAF, 53% MSA). Chest pain occurred mainly in patients with PAF (44% PAF, 13% MSA). Improvement occurred with sitting or lying flat. Non-specific symptoms (weakness, lethargy and fatigue) were common in both groups (91% PAF, 85% MSA); six patients (one PAF, five MSA) had these symptoms only. Postural symptoms (mainly dizziness and neck pain) were worse in the morning and with warm temperature, straining, exertion, arm movements and food ingestion; they were more common in PAF. Compensatory autonomic symptoms, such as palpitations and sweating, did not occur in either group. In conclusion, orthostatic hypotension caused symptoms of cerebral hypoperfusion (syncope, dizziness and visual disturbances); neck pain, presumably due to muscle hypoperfusion, also occurred frequently. These symptoms were exacerbated by various factors in daily life and were relieved by returning to the horizontal. Non-specific symptoms (such as fatigue) also were common. In MSA, despite substantial orthostatic hypotension, fewer patients had syncope, visual disturbance and neck pain; the reasons for this are unclear. Lack of these features does not exclude the need to assess and investigate orthostatic hypotension and possible autonomic failure.
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PMID:Symptoms associated with orthostatic hypotension in pure autonomic failure and multiple system atrophy. 1055 35


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