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Autonomic Nervous System Testing Name of Blue Advantage Policy: Autonomic Nervous System Testing Policy #: 573 Latest Review Date: July 2020 Category: Medicine Policy Grade: Effective July 8, 2020: Active policy but no longer scheduled for regular literature reviews and updates. BACKGROUND: Blue Advantage medical policy does not conflict with Local Coverage Determinations (LCDs), Local Medical Review Policies (LMRPs) or National Coverage Determinations (NCDs) or with coverage provisions in Medicare manuals, instructions or operational policy letters. In order to be covered by Blue Advantage the service shall be reasonable and necessary under Title XVIII of the Social Security Act, Section 1862(a)(1)(A). The service is considered reasonable and necessary if it is determined that the service is: 1. Safe and effective; 2. Not experimental or investigational*; 3. Appropriate, including duration and frequency that is considered appropriate for the service, in terms of whether it is: • Furnished in accordance with accepted standards of medical practice for the diagnosis or treatment of the patient’s condition or to improve the function of a malformed body member; • Furnished in a setting appropriate to the patient’s medical needs and condition; • Ordered and furnished by qualified personnel; • One that meets, but does not exceed, the patient’s medical need; and • At least as beneficial as an existing and available medically appropriate alternative. *Routine costs of qualifying clinical trial services with dates of service on or after September 19, 2000 which meet the requirements of the Clinical Trials NCD are considered reasonable and necessary by Medicare. Providers should bill Original Medicare for covered services that are related to clinical trials that meet Medicare requirements (Refer to Medicare National Coverage Determinations Manual, Chapter 1, Section 310 and Medicare Claims Processing Manual Chapter 32, Sections 69.0-69.11). Page 1 of 13 Proprietary Information of Blue Cross and Blue Shield of Alabama An Independent Licensee of the Blue Cross and Blue Shield Association Blue Advantage Medical Policy #573 POLICY: Effective for dates of service on and after February 26, 2018: Blue Advantage will treat autonomic nervous system testing, consisting of a battery of tests in several domains as a covered benefit when the following criteria are met: • Signs and/or symptoms of autonomic dysfunction are present; AND • A definitive diagnosis cannot be made from clinical examination and routine laboratory testing alone; AND • Diagnosis of the suspected autonomic disorder will lead to a change in management or will eliminate the need for further testing. Blue Advantage will treat autonomic nervous system testing as a non-covered benefit and as investigational in all other situations when criteria are not met, including but not limited to the evaluation of the following conditions: • chronic fatigue syndrome; • fibromyalgia; • anxiety and other psychologic disorders; • sleep apnea; • allergic conditions; • hypertension; • screening of asymptomatic individuals; • monitoring progression of disease or response to treatment. Blue Advantage will treat autonomic nervous system testing using portable automated devices as a non-covered benefit and as investigational for all indications. Although there is not a standard battery of tests that are part of ANS testing, a full battery of testing generally consists of individual tests in 3 domains. • Cardiovagal function (heart rate [HR] variability, HR response to deep breathing and Valsalva) • Vasomotor adrenergic function (blood pressure [BP] response to standing, Valsalva, and hand grip, tilt table testing) • Sudomotor function (QSART, QST, TST, silastic sweat test) At least one test in each category is usually performed. More than one test from a category will often be included in a battery of tests, but the incremental value of using multiple tests in one domain is not known. There is little evidence on the comparative accuracy of different ANS tests, but the following tests are generally considered to have uncertain value in ANS testing: • Pupillography • Pupil edge light cycle • Gastric emptying tests • Cold pressor test • QDIRT test • Plasma catecholamine levels • Skin vasomotor testing Page 2 of 13 Proprietary Information of Blue Cross and Blue Shield of Alabama An Independent Licensee of the Blue Cross and Blue Shield Association Blue Advantage Medical Policy #573 • The ANSAR® test Autonomic nervous system should be performed in a dedicated autonomic nervous system testing laboratory. Testing in a dedicated laboratory should be performed under closely controlled conditions, and interpretation of the results should be performed by an individual with expertise in autonomic nervous system testing. Testing using automated devices with interpretation of the results performed by computer software has not been validated and thus has the potential to lead to erroneous results. POLICY GUIDELINES: Although there is no standard battery of tests for autonomic nervous system (ANS) testing, a full battery generally consists of individual tests in three categories. • Cardiovagal function (heart rate variability, heart rate response to deep breathing and Valsalva maneuver) • Vasomotor adrenergic function (blood pressure response to standing, Valsalva maneuver, and hand grip, tilt table testing) • Sudomotor function (Quantitative Sudomotor Axon Reflex Test, quantitative sensory test, Thermoregulatory Sweat Test, silastic sweat imprint, sympathetic skin response, electrochemical sweat conductance). At least one test in each category is usually performed. More than one test from a category will often be included in a battery of tests, but the incremental value of using multiple tests in a category is unknown. There is little evidence on the comparative accuracy of different ANS tests, but the following tests are generally considered to have uncertain value in ANS testing: • Pupillography • Pupil edge light cycle • Gastric emptying tests • Cold pressor test • Quantitative direct and indirect testing of sudomotor function test • Plasma catecholamine levels • Skin vasomotor testing • The ANSAR® test. ANS testing should be performed in a dedicated ANS testing laboratory. Testing in a dedicated laboratory should be performed under closely controlled conditions, and an individual with expertise in ANS testing should interpret results. Testing using automated devices with results interpreted by computer software has not been validated and thus has the potential to lead to erroneous results. Blue Advantage does not approve or deny procedures, services, testing, or equipment for our members. Our decisions concern coverage only. The decision of whether or not to have a certain test, treatment or procedure is one made between the physician and his/her patient. Blue Advantage administers benefits based on the members' contract and medical policies. Physicians Page 3 of 13 Proprietary Information of Blue Cross and Blue Shield of Alabama An Independent Licensee of the Blue Cross and Blue Shield Association Blue Advantage Medical Policy #573 should always exercise their best medical judgment in providing the care they feel is most appropriate for their patients. Needed care should not be delayed or refused because of a coverage determination. DESCRIPTION OF PROCEDURE OR SERVICE: The autonomic nervous system (ANS) controls physiologic processes that are not under conscious control. ANS testing consists of a battery of individual tests that are intended to evaluate the integrity and function of the ANS. These tests are intended to be adjuncts to the clinical examination in the diagnosis of ANS disorders. Autonomic Nervous System The autonomic nervous system (ANS) has a primary role in controlling physiologic processes not generally under conscious control. They include heart rate, respirations, gastrointestinal (GI) motility, thermal regulation, bladder control, and sexual function. The ANS is a complex neural regulatory network that consists of two complementary systems that work to maintain homeostasis: the sympathetic and the parasympathetic systems. The sympathetic nervous system is responsible for arousal, and sympathetic stimulation leads to increased pulse, increased blood pressure (BP), increased sweating, decreased GI motility, and an increase on other glandular exocrine secretions. This is typically understood as the “fight or flight” response. Activation of the parasympathetic nervous system will mostly have the opposite effects; BP and pulse will decrease, GI motility increases, and there will be a decrease in sweating and other glandular secretions. ANS Disorders ANS disorders, also called dysautonomias, are heterogeneous in etiology, clinical symptoms, and severity. ANS disorders can be limited and focal, such as patients with isolated neurocardiogenic syncope or idiopathic palmar hyperhidrosis. At the other extreme, some ANS disorders can be widespread and severely disabling, such multiple systems atrophy, which leads to widespread and severe autonomic failure. Symptoms of autonomic disorders can vary, based on the etiology and location of dysfunction. Cardiovascular manifestations are often prominent. Involvement of the cardiovascular system causes abnormalities in heart rate control and vascular dynamics. Orthostatic hypotension and other manifestations of BP lability can occur, causing weakness, dizziness, and syncope. Resting tachycardia and an inability to appropriately increase heart rate in response to exertion leads to exercise
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