THE ASSESSMENT OF AUTONOMIC FUNCTION IN PATIENTS WITH SYSTEMIC AMYLOIDOSIS - METHODOLOGICAL CONSIDERATIONS

Autonomic neuropathy is a well-known and prognostically important feat ure of systemic amyloidosis. In other conditions, autonomic function i s commonly assessed by cardiovascular reflex rests, described by Ewing , but the feasibility of these tests has not been investigated in pati ents with systemic amyloidosis. We studied autonomic function in amylo idotic patients using cardiovascular tests and assessed their feasibil ity. Patients with AA, AL and ATTR amyloidosis participated. In all pa tients, cardiovascular reflex testing (mental arithmetic stress test a nd head-lip tilting, besides the Ewing-tests) was performed. Of the 46 patients included, only 28 patients could perform all 4 Ewing-tests. In particular, patients with AA amyloidosis secondary to rheumatoid ar thritis could not perform standing up and the isometric handgrip test, However, when the mental stress test replaced the handgrip test and h ead-up tilting replaced standing up, in 45 of the 46 patients, autonom ic function could be assessed with cardiovascular reflex tests. Half o f the patients with AA amyloidosis had signs of autonomic neuropathy-w hich was more than expected. We propose to replace the isometric handg rip test with the mental arithmetic stress test and standing up with h ead-up tilting if a patient is not able to perform these tests.