In this hyperendemic area, an important proportion of seizure cases are associated with neurocysticercosis as demonstrated by serology or brain CT.
Orthostatic hypotension is a chronic, debilitating illness that is difficult to treat. The therapeutic goal is to improve postural symptoms, standing time, and function rather than to achieve upright normotension, which can lead to supine hypertension. Drug therapy alone is never adequate. Because orthostatic stress varies with circumstances during the day, a patient-oriented approach that emphasizes education and nonpharmacologic strategies is critical. We provide easy-to-remember management recommendations, using a combination of drug and non-drug treatments that have proven efficacious.Orthostatic hypotension is a chronic, debilitating illness associated with common neurologic conditions (eg, diabetic neuropathy, Parkinson disease). It is common in the elderly, especially in those who are institutionalized and are using multiple medications.Treatment can be challenging, especially if the problem is neurogenic. This condition has no cure, symptoms vary in different circumstances, treatment is nonspecific, and aggressive treatment can lead to marked supine hypertension.This review focuses on the prevention and treatment of neurogenic causes of orthostatic hypotension. We emphasize a simple but effective patient-oriented approach to management, using a combination of nonpharmacologic strategies and drugs clinically proven to be efficacious. The recommendations and their rationale are organized in a practical and easy-toremember format for both physicians and patients. WHAT HAPPENS WHEN WE STAND UP?When we stand up, the blood goes down from the chest to the distensible venous capacitance system below the diaphragm. This fluid shift produces a decrease in venous return, ventricular filling, cardiac output, and blood pressure. 1 This gravity-induced drop in blood pressure, detected by arterial baroreceptors in the aortic arch and carotid sinus, triggers a compensatory reflex tachycardia and vasoconstriction that restores normotension in the upright position. This compensatory mechanism is termed a baroreflex; it is mediated by afferent and efferent autonomic peripheral nerves and is integrated in autonomic centers in the brainstem. Orthostatic hypotension is the result of baroreflex failure (autonomic failure), end-organ dysfunction, or volume depletion. Injury to any limb of the baroreflex causes neurogenic orthostatic hypo tension, although with afferent lesions alone, the hypotension tends to be modest and accompanied by wide fluctuations in blood pressure, including severe hypertension. Drugs can produce orthostatic hypotension by interfering with the autonomic pathways or their target end-organs or by affecting intravascular volume. Brain hypoperfusion, resulting from orthostatic hypotension from any cause, can lead to symptoms of orthostatic intolerance (eg, lightheadedness) and falls, and if the hypotension is severe, to syncope. A DECREASE OF 20 MM HG SYSTOLIC OR 10 MM HG DIASTOLICThe consensus definition of orthostatic hypotension is a reduction of systolic blood pressure of at least 20 mm Hg or a ...
Background Neurologic and autonomic presentation in multiple system atrophy (MSA) may predict early mortality. Quantification of early autonomic failure as mortality predictor is lacking. Methods Early neurologic and autonomic clinical features were retrospectively reviewed in 49 MSA cases (median age at onset, 56.1 years; 16 women) confirmed by autopsy at Mayo Clinic. When available, the 10-point composite autonomic severity score derived from the autonomic reflex screen provided quantification of the degree of autonomic failure and thermoregulatory sweat test quantitated body surface anhidrosis. Results Symptoms at onset were autonomic in 50%, parkinsonian in 30%, and cerebellar in 20% of cases. Survival (median [95% confidence interval]) was 8.6 [6.7–10.2] years. Survival was shorter in patients with early laboratory evidence of generalized (composite autonomic severity score ≥ 6) autonomic failure (7.0 [3.9–9.8] vs. 9.8 [4.6–13.8] years; P=0.036), and early requirement of bladder catheterization (7.3 [3.1–10.2] vs. 13.7 [8.5–14.9] years; P=0.003) compared to those without these clinical features. On Cox proportional analysis, prognostic indicators of shorter survival were older age at onset (hazard ratio [95% confidence interval], 1.04 [1.01–1.08]; P=0.03), early requirement of bladder catheterization (7.9 [1.88–38.63]; P=0.004) and early generalized (composite autonomic severity score ≥ 6) autonomic failure (2.8 [1.01–9.26]; P=0.047). Gender, phenotype, and early development of gait instability, aid-requiring ambulation, orthostatic symptoms, neurogenic bladder or significant anhidrosis (thermoregulatory sweat test ≥ 40%) were not indicators of shorter survival. Conclusions Our data suggests that early development of severe generalized autonomic failure more than triples the risk of shorter survival in patients with MSA.
Background Multiple system atrophy (MSA) is a sporadic progressive neurodegenerative disorder characterised by autonomic failure, manifested as orthostatic hypotension or urogenital dysfunction, with combinations of parkinsonism that is poorly responsive to levodopa, cerebellar ataxia and corticospinal dysfunction. Published autopsy confirmed cases have provided reasonable neurological characterisation but have lacked adequate autonomic function testing. Objectives To retrospectively evaluate if the autonomic characterisation of MSA is accurate in autopsy confirmed MSA and if consensus criteria are validated by autopsy confirmation. Methods 29 autopsy confirmed cases of MSA evaluated at the Mayo Clinic who had undergone formalised autonomic testing, including adrenergic, sudomotor and cardiovagal functions and Thermoregulatory Sweat Test (TST), from which the Composite Autonomic Severity Score (CASS) was derived, were included in the study. Results Patient characteristics: 17 men, 12 women; age of onset 57±8.1 years; disease duration to death 6.5±3.3 years; first symptom autonomic in 18, parkinsonism in seven and cerebellar in two. Clinical phenotype at first visit was MSA-P (predominant parkinsonism) in 18, MSA-C (predominant cerebellar involvement) in eight, pure autonomic failure in two and Parkinson’s disease in one. Clinical diagnosis at last visit was MSA for 28 cases. Autonomic failure was severe: CASS was 7.2±2.3 (maximum 10). TST% was 65.6±33.9% and exceeded 30% in 82% of patients. The most common pattern was global anhidrosis. Norepinephrine was normal supine (203.6±112.7) but orthostatic increment of 33.5±23.2% was reduced. Four clinical features (rapid progression, early postural instability, poor levodopa responsiveness and symmetric involvement) were common. Conclusion The pattern of severe and progressive generalised autonomic failure with severe adrenergic and sudomotor failure combined with the clinical phenotype is highly predictive of MSA.
Objective: To prospectively evaluate patients who met standard criteria for postural tachycardia syndrome (POTS), at baseline and 1-year follow-up, using standard clinical and laboratory methods to assess autonomic function. Methods: Fifty-eight patients met the study criteria (orthostatic symptoms and a heart rate increment of Ն30 beats/min on head-up tilt) and completed 12 months of follow-up. All patients were enrolled and completed the study from January 16, 200616, , through April 15, 2009. Patients underwent standardized autonomic testing, including head-up tilt, clinical assessment, and validated questionnaires designed to determine the severity of autonomic symptoms. Results: Patients were predominantly young females (nϭ49, 84%), with 20 patients (34%) reporting an antecedent viral infection before onset of symptoms. More than one-third (37%) no longer fulfilled tilt criteria for POTS on follow-up, although heart rate increment on head-up tilt did not differ significantly at 1 year (33.8Ϯ15.1 beats/min) compared with baseline (37.8Ϯ14.6 beats/min) for the entire cohort. Orthostatic symptoms improved in most patients. Autonomic dysfunction was mild as defined by a Composite Autonomic Severity Score of 3 or less in 55 patients (95%) at baseline and 48 patients (92%) at 1 year. Conclusion: To our knowledge, this is the first prospective study of the clinical outcomes of patients with POTS. Orthostatic symptoms improved in our patients, with more than one-third of patients no longer fulfilling tilt criteria for POTS, although the overall group change in heart rate increment was modest. Our data are in keeping with a relatively favorable prognosis in most patients with POTS. P ostural tachycardia syndrome (POTS) is defined by symptoms of orthostatic intolerance associated with heart rate increments greater than 30 beats/min on head-up tilt (HUT), with the more severe cases reaching standing heart rates of greater than 120 beats/min.1 Symptoms related to orthostatic changes most often include light-headedness, palpitations, presyncope, and symptom exacerbations caused by heat or exercise.2 The disorder begins primarily between 15 and 50 years of age (with a mean age at onset of 30 years) and is characterized by a strong female predominance. 1-5The pathophysiologic and etiologic mechanisms of POTS are heterogeneous in nature. Several important subtypes of primary POTS have been described. Neuropathic POTS describes a subgroup with length-dependent denervation of sympathetic fibers in the lower extremity. 6 In keeping with this denervation, these patients have impaired norepinephrine spillover, resulting in isolation to the legs. Approximately half of patients diagnosed as having primary POTS manifest this restricted autonomic neuropathy pattern.2,7 A second hyperadrenergic subtype has been defined by increased systolic blood pressure during HUT (Ն10 mm Hg) and an elevated plasma norepinephrine level (Ն600 pg/mL [to convert to pmol/L, multiply by 5.911]).8 These patients have episodes of tachycardia and...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.