Evidence for Impaired Renin Activity in Postural Orthostatic Tachycardia Syndrome

Background: Postural orthostatic tachycardia syndrome (POTS) is a heterogeneous condition predominantly affecting autonomic control of the cardiovascular system. Its extensive symptom diversity implies multi-organ involvement that interacts in ways still requiring full exploration. Current understanding POTS pathophysiology suggests alterations renin–angiotensin–aldosterone system as possible contributing factor. Therefore, we investigated relationship between activity and hemodynamic parameters cohort patients controls recruited at tertiary referral center. Methods: The case-control study included 46 with (27 ± 9 years), 48 healthy (30 years) without intolerance. Plasma renin activity, expressed angiotensin I generation, plasma aldosterone were measured by enzyme-linked immunosorbent assay correlated obtained during active standing tests. Results: Renin was significantly downregulated compared to individuals (median, 3406 ng/mL vs. 9949 ng/mL, p < 0.001), whereas concentration did not differ 218 pmol/L pmol/L, = 0.26). A significant inverse correlation supine blood pressure levels observed (p 0.05 for all), but patients. Conclusions: concentration, POTS. Moreover, dissociated from contrast individuals. These findings suggest impaired function POTS, which may direct future therapeutic approaches.