Uncontrolled blood pressure before covid-19 is associated with elevated serum il-17 and long-covid sequelae in hemodialysis patients

Objective: Hypertension, a nearly ubiquitous complication in hemodialysis (HD) patients, has been identified as a risk factor for COVID -19 and its associated adverse outcomes. In turn, both hypertensive and COVID-19-infected patients with long- COVID sequelae have been reported to have elevated serum interleukin-17 (IL-17) levels. Although HD patients belong to the high-risk group for long COVID sequelae, the association between pre-infection blood pressure (BP) control, serum IL-17 levels, and long COVID sequelae has never been investigated in this cohort. Design and method: A total of 80 HD patients aged 56 (44-63.2) years with a dialysis vintage of 40 (23-74) months who had experienced COVID-19 before enrollment were included in this cross-sectional cohort study. Controlled BP was defined as a 3-month average pre-dialysis BP < 140/90 mmHg and post-dialysis < 130/80 mmHg. IL-17 was measured at least 5 months after acute COVID-19 by ELISA assay. Data were expressed as proportion or median (Me) and interquartile ranges (Q25-Q75) and compared with the Chi-squared test or the Mann-Whitney test as appropriate. Results: Of the 80 patients included, 46 (57.5%) had uncontrolled BP and 34 (42.5%) had controlled BP before infection with COVID -19. Long-term COVID sequelae were observed in 26/46 (56.5%) patients with uncontrolled BP and 11/34 (32.4%) of the BP -controlled group (⇙ 2 = 4.6, p = 0.03). Serum levels of IL-17 ranged from 0.01 to 15.14 pg/ml and were significantly higher in patients with uncontrolled BP than in the controlled BP group [0.34 (0.08-0.98) vs 0.06 (0.03-0.14) pg/mL, p = 0.001]. In addition, IL-17 was also higher in patients with long-COVID sequelae than in fully recovered patients [0.43 (0.07-1.58) vs 0.08 (0.02-0.16) pg/mL, p = 0.0003], while those with long-COVID sequelae and preinfection uncontrolled BP had the highest value IL-17 (p = 0.04) (Fig. 1). Conclusions: Uncontrolled BP before COVID-19 is associated with increased serum IL-17 levels and long-COVID sequelae in HD patients. Further studies are needed to understand the role of IL-17 in BP control and long-term COVID sequelae in HD patients.