The role of autoantibodies in the syndromes of orthostatic intolerance: a systematic review

Abstract

Orthostatic intolerance is defined as the provocation of symptoms upon standing, commonly caused by neurogenic orthostatic hypotension (OH) and postural tachycardia syndrome (POTS), the etiology for which has not been fully uncovered yet. Many reports have described the occurrence of dysautonomia, orthostatic intolerance and POTS following febrile illness, presumably viral and post-vaccine. Furthermore, patients with dysautonomia have higher rates of autoimmune disorders such as Hashimoto thyroiditis and SLE. Recent evidence has shown the presence of adrenergic and cholinergic receptor antibodies in patients with POTS and orthostatic hypotension. In patients with cholinergic receptor antibodies, higher titers correlate with the disease severity. Few reports have shown that immunomodulation therapy resulted in significant improvement in symptoms. In this article, we review the available literature correlating autoimmunity with orthostatic intolerance syndromes. Future studies are warranted to evaluate the prevalence of such antibodies and examine different treatment modalities in this sub group of patients.

Family history of associated disorders in patients with postural tachycardia syndrome

“…5 These findings would fit with the fact that autoantibodies to autonomic receptors have been found in affected patients, although actual causation has not been established. [10][11][12][13] We also found that just over half of our patients had some aspect of joint hypermobility, with either hypermobile Ehlers-Danlos syndrome or hypermobility spectrum disorder. 5 This also has been borne out in other studies, [14][15][16] suggesting a strong association with this disorder, as well.…”

Postural orthostatic tachycardia syndrome in children and adolescents

“…These all suggest a possible autoimmune etiology for POTS. Anti-adrenergic and anti-muscarinic antibodies have been found in the majority of POTS patients in small studies, although their actual causation has not been proven (Ruzieh et al, 2017). Further research on possible autoimmune mechanisms in POTS is underway.…”

Postural orthostatic tachycardia syndrome: clinical presentation, aetiology and management

“…In recent years, search for the presence of a hypothetical immunological fingerprint in POTS has resulted in a discovery of diverse autoantibodies with a proposed causative role in the syndrome . A specific focus was given cardiovascular G‐protein‐coupled membrane complexes, such as adrenergic, muscarinic and angiotensin II type‐1 receptors The symptoms of POTS, especially tachycardia, could be evoked by the direct action on sinus rate controlling system (via adrenergic and muscarinic receptors) or through a compensatory mechanism responding to peripheral vasodilation (via adrenergic, angiotensin and other possible vasoactive receptors) (Fig.…”

“…This attractive hypothesis awaits verification in larger and independent patient populations and well‐selected control groups. An interested reader is recommended to consult some of recently published reviews on the subject . Other autoantibodies with a proposed aetiological role in POTS include antibodies against nicotinic acetylcholine‐receptor in autonomic ganglia and Sjögren autoantibodies , detected in POTS through antibody screening programmes.…”