Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0015672 (fatigue)
 51,768 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Patients with chronic open angle glaucoma are traditionally managed by medical therapy during the early stages of the disease. Pilocarpine is a well established topical agent, but suffers troublesome sequelae, the most apparent of which is pupillary constriction. This study assesses the effect of miosis (produced by one drop of 2% pilocarpine) on the static threshold perimetry of 20 subjects with chronic open angle glaucoma and documented visual field loss, using the 30-2 program of the Humphrey field analyser. Following miosis, the Statpac mean defect deteriorated by an average of -1.49 dB compared with baseline (p = 0.004). This dB deterioration is twice that reported in studies on younger normal subjects following miosis. The decrease in mean defect showed a positive correlation with the degree of pupillary constriction, the correlation being greater in those eyes with a miosed pupil diameter of 2 mm or less. There was no significant decrease in the other Statpac global indices following miosis. A parallel study using the fellow eye of the same glaucoma patients showed a high degree of intertest variability, but no significant learning or fatigue effect. We conclude that pilocarpine-induced miosis causes a significant deterioration in visual field in a population of patients with chronic open angle glaucoma: this factor should be considered when choosing therapy for glaucoma particularly in cases where field loss approaches the permitted legal minimum for driving.
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PMID:The effect of pilocarpine on the glaucomatous visual field. 828 Jun 87

We studied the effect of fatigue within a 10 degree visual field measured with automated perimetry in normal volunteers (10 eyes), patients who have recovered from optic neuritis with multiple sclerosis (10 eyes), and patients with glaucoma (10 eyes). Using an Octopus 201, the visual field was tested with Program 61, which was centered (0.0), and 25 test locations were determined three times. Eight of the 25 points were selected for the evaluation. The mean sensitivity of the eight points was compared among the three measurements. Normal subjects and patients with optic neuritis showed no effect of fatigue within the 10 degrees visual field, but the patients with glaucoma indicated fatigue during the third measurement.
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PMID:Fatigue effect within 10 degrees visual field in automated perimetry. 848 56

Clinical trials were conducted to evaluate brimonidine tartrate, an alpha 2-adrenoceptor agonist, for treating chronically elevated intraocular pressure (IOP) and the prophylactic treatment of acute pressure rises. In normal volunteers, brimonidine administered twice daily for five days at concentrations ranging from 0.08-0.5% lowered IOP 16-22% and was well-tolerated ocularly and systemically. In a 28-day study in 186 patients with glaucoma or ocular hypertension, maximum IOP lowering was 27.2% and 30.1% for brimonidine 0.2% and 0.5%, respectively. The most common adverse events were dry mouth fatigue/drowsiness, and blurring, which occurred significantly more frequently with brimonidine 0.5% than 0.2%. Brimonidine 0.5% was tested in 471 patients undergoing argon laser trabeculoplasty (ALT). One drop administered preoperatively, postoperatively or both pre- and postoperatively significantly reduced the number of postoperative IOP spikes (1-2% of patients compared to 23% receiving only vehicle). Systemic hypotension, dry mouth, lid retraction and conjunctival blanching occurred more frequently in patients who received the drug twice. Brimonidine 0.2% twice daily was compared with three times daily in 101 patients. No significant differences were seen between the two regimens in mean change from baseline IOP with mean decreases ranging from 3.4 +/- 3.23 to 5.2 +/- 3.77 mm Hg (standard deviation) with twice daily dosing, and from 2.8 +/- 3.26 to 4.9 +/- 3.70 mm Hg with three times daily dosing. The most common complaints were blurring and oral dryness. Based upon results of these and other early studies, brimonidine 0.5% was selected for acute therapy for the prevention of postoperative intraocular pressure spikes and brimonidine 0.2% for chronic use in glaucoma and ocular hypertension.
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PMID:Development and use of brimonidine in treating acute and chronic elevations of intraocular pressure: a review of safety, efficacy, dose response, and dosing studies. 897 Feb 46

Perimetry is a cornerstone in glaucoma management. The detection of glaucomatous visual field loss is of crucial importance for diagnosing the disease. Automated threshold perimetry makes thorough testing of the central visual field very possible and high-quality data are often achieved. Certain factors, however, may hamper the visual field examination or visual field interpretation. Many diseases other than glaucoma are known to influence the visual field in more or less predictable ways. Of interest is also low patient reliability, learning and fatigue effects, as well as test artifacts and suboptimal test strategies or parameters. Finally, statistical aids provided by the built-in computer of the perimeter must be judged keeping in mind the population from which the patient is derived. We describe such pitfalls in glaucoma perimetry, how they can be identified, and dealt with clinically.
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PMID:Pitfalls of automated perimetry in glaucoma diagnosis. 1015 Aug 57

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

Glaucoma can be considered a disease of the aging eye. Most medications used to treat glaucoma are in topical eyedrop form and may cause numerous untoward systemic effects in older persons. In recent years, several new ocular hypotensive medications have become available. These medications are being used more commonly because there is a growing trend by ophthalmologists to aggressively lower intraocular pressure. Therefore, geriatricians require a comprehensive knowledge of medications used to treat glaucoma, in addition to an understanding of their mechanism of action profiles of untoward effects and possible interactions with other diseases or medications. Therefore, we performed a review of the medications recently introduced into clinical practice. We selected drugs approved by the U.S. Food and Drug Administration between 1996 and September 2001. The safety profiles of these agents and their untoward side effects were reviewed by class: topical carbonic anhydrase inhibitors (brinzolamide: ocular tolerance, taste perversion), beta-adrenoceptor antagonists (timolol: bradycardia and bronchospasm), alpha-adrenergic agonists (brimonidine: oral dryness, headache, and fatigue), and prostaglandin analogs (latanoprost, bimatoprost, travoprost, and unoprostone isopropyl: ocular hyperemia, iris color changes). The function of this review is to make geriatricians more aware of the efficacy and untoward effects of medications recently introduced into clinical practice. We recommend that geriatricians perform a medication review on all medications their patients use, including eye drops.
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PMID:New glaucoma medications in the geriatric population: efficacy and safety. 1202 87

Computer perimetry is constantly being developed but still remains a subjective examination method. The patient's cooperation plays an important part and therefore examination strategies are improved to make it possible to obtain the most accurate possible results during the shortest possible examination time. The author presents an account on the comparability of results of rapid TOP strategy (Tendency Oriented Perimetry) and normal threshold strategy with programme G2 on the perimeter OCTOPUS 101. It involves the retrospective evaluation of 73 visual fields which were divided into four groups according to the achieved retinal sensitivity during examination with TOP strategy and with normal threshold strategy. The author compared the obtained parameters MD and LV, she compared the sites of defects of retinal sensitivity in both strategies and calculated the time saved by rapid TOP strategy. High comparability was achieved in group 1 with normal retinal sensitivity in both strategies and also in group 4 with abnormal retinal sensitivity in both strategies. In groups 2 and 3 comparability was not proved (group 2--abnormal retinal sensitivity in TOP and normal retinal sensitivity in normal threshold strategy, group 3--normal retinal sensitivity in TOP and abnormal retinal sensitivity in normal threshold strategy). In these groups we may assume a higher ratio of the so-called learning effect or conversely fatigue and poorer cooperation of the patients during the lengthy examination by normal threshold strategy. The localization of defects agreed in group 4 in 83.3% and in the other groups it was not compared (group 1 practically without defects, in groups 2 and 3 the results were not comparable). The total time saved with TOP strategy was 75.8%, the mean examination time with TOP strategy was 3 minutes 27 seconds, with normal threshold strategy 14 minutes 17 seconds. With regard to the significant time saving the programme G2 with TOP strategy can be considered suitable for patients with glaucoma, with intraocular hypertension and with suspected glaucoma but it can be also used as a screening method with quantitative results for other situations.
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PMID:[Computer perimetry--rapid TOP (tendency oriented perimetry) and normal threshold methods in clinical practice--comparison of results]. 1208 65

This study intended to evaluate the advantages of brimonidine tartrate 0.2% (Alphagan((R))), a selective alpha-2 receptor agonist, relaying a poorly tolerated beta-blocker treatment. Effectiveness, as assessed by intraocular pressure, local and general tolerance of the treatment, and the quality of life of the patients included in the study, was compared for these two eye drops. This multicenter and prospective study, performed by 450 ophthalmologists, included 807 adults presenting with glaucoma or ocular hypertony over 8 months. After a poorly tolerated beta-blocker treatment, which had started at least 6 months before, these patients received brimonidine over 8 weeks. At 3 successive visits, intraocular pressure, biomicroscopic examination results, and visual acuity were recorded. A quality-of-life questionnaire evaluating breathlessness, fatigue, depressive mood, loss of appetite, and satisfaction with the treatment was also given to patients. In the 731 patients observed in the study, the analysis concluded a statistically significant decrease in intraocular pressure (-2.5mmHg) and in the cardiovascular parameters during brimonidine treatment: blood pressure was reduced by 3mmHg and 1.1mmHg for systolic and diastolic pressure, respectively. The heart rate rose by 1.7 beats/min. The quality-of-life questionnaire revealed less breathlessness (-26%), fatigue (-24.9%), depressive mood (-19.3%), and better appetite (+8.2%). The feeling of satisfaction with the brimonidine treatment was significantly improved for 95 patients. However, 12% of all patients stopped their treatment because of adverse effects. Brimonidine improved the glaucomatous patients' quality of life, at least in some areas. Improved intraocular pressure could at least in part result from better compliance with the treatment. Brimonidine is an encouraging alternative after an unsatisfactory beta-blocker treatment.
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PMID:[Use of brimonidine 0.2% in treatment of glaucoma or ocular hypertony after poorly tolerated beta-blocker treatment]. 1222 42

Mitochondriopathies (MCPs) are either due to sporadic or inherited mutations in nuclear or mitochondrial DNA located genes (primary MCPs), or due to exogenous factors (secondary MCPs). MCPs usually show a chronic, slowly progressive course and present with multiorgan involvement with varying onset between birth and late adulthood. Although several proteins with signalling, assembling, transport, enzymatic function can be impaired in MCP, most frequently the activity of the respiratory chain (RC) protein complexes is primarily or secondarily affected, leading to impaired oxygen utilization and reduced energy production. MCPs represent a diagnostic challenge because of their wide variation in presentation and course. Systems frequently affected in MCP are the peripheral nervous system (myopathy, polyneuropathy, lactacidosis), brain (leucencephalopathy, calcifications, stroke-like episodes, atrophy with dementia, epilepsy, upper motor neuron signs, ataxia, extrapyramidal manifestations, fatigue), endocrinium (short stature, hyperhidrosis, diabetes, hyperlipidaemia, hypogonadism, amenorrhoea, delayed puberty), heart (impulse generation or conduction defects, cardiomyopathy, left ventricular non-compaction heart failure), eyes (cataract, glaucoma, pigmentary retinopathy, optic atrophy), ears (deafness, tinnitus, peripheral vertigo), guts (dysphagia, vomiting, diarrhoea, hepatopathy, pseudo-obstruction, pancreatitis, pancreas insufficiency), kidney (renal failure, cysts) and bone marrow (sideroblastic anaemia). Apart from well-recognized syndromes, MCP should be considered in any patient with unexplained progressive multisystem disorder. Although there is actually no specific therapy and cure for MCP, many secondary problems require specific treatment. The rapidly increasing understanding of the pathophysiological background of MCPs may further facilitate the diagnostic approach and open perspectives to future, possibly causative therapies.
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PMID:Mitochondriopathies. 1500 63

Inhibition of carbonic anhydrase (CA, EC 4.2.1.1) isoforms present in the eyes (CA I, II, IV and XII), with sulfonamides such as acetazolamide, methazolamide, ethoxzolamide and dichlorophenamide, is still widely used for the systemic treatment of glaucoma. The mechanism of action of these drugs consists in inhibition of CA isozymes present in ciliary processes of the eye, with the consequent reduction of bicarbonate and aqueous humour secretion, and of elevated intraocular pressure (IOP) characteristic of this disease. As isoforms CA II/IV/XII are present in many other tissues/organs, generally, systemic CAIs possess undesired side effects such as numbness and tingling of extremities; metallic taste; depression; fatigue; malaise; weight loss; decreased libido; gastrointestinal irritation; metabolic acidosis; renal calculi and transient myopia. For avoiding these side effects, recently, topically effective CAIs have been developed in the last 10 years, with two drugs available clinically: dorzolamide and brinzolamide. Both these drugs are applied topically as water solutions/suspensions, alone or in combination with other agents (beta-blockers, prostaglandin derivatives, etc) and produce a consistent and prolonged reduction of IOP. Furthermore, recent reports show both the systemically as well as topically acting sulfonamide CAIs to be effective in the treatment of macular edema, macular degeneration disease, or diabetic retinopathy, for which pharmacological treatment is unavailable up to now. Much research is in act in the search of more effective topically acting CAIs, free of the inconveniences and side effects of the presently available drugs. For achieving this goal, two recently reported strategy, the tail approach and its variant, the sugar-tail approach, were extensively applied for the synthesis of large numbers of derivatives possessing desired physico-chemical properties. Many such new sulfonamides showed promising antiglaucoma activity in animal models of the disease.
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PMID:The development of topically acting carbonic anhydrase inhibitors as antiglaucoma agents. 1833 10


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