Objective: To evaluate microRNA-associated inflammatory and vascular alterations in patients with Long COVID, with particular emphasis on arterial hypertension as a modifier of cardiovascular risk. Design and method: A total of 102 adults were assessed at least 4 weeks after acute SARS-CoV-2 infection and stratified according to the presence of arterial hypertension (hypertensive group, n=50; non-hypertensive group, n=52). Plasma levels of microRNAs associated with immune and vascular regulation (hsa-miR-155-5p and hsa-miR-28-5p) were quantified using reverse transcription quantitative polymerase chain reaction. Relative expression was analysed using the delta Ct method with an exogenous synthetic microRNA as an internal control. Correlation analyses and statistical comparisons were performed to evaluate associations between microRNA expression, inflammatory markers and cardiovascular parameters. Results: Hypertensive patients exhibited significantly increased expression of hsa-miR-155-5p and reduced expression of hsa-miR-28-5p compared with non-hypertensive individuals (p<0.0001). These molecular alterations were accompanied by elevated levels of inflammatory markers, including C-reactive protein, interleukin-6 and ferritin, as well as markers of cardiac stress and coagulation activity. In contrast, non-hypertensive patients demonstrated more stable microRNA expression patterns consistent with a less pronounced inflammatory response. Conclusions: hsa-miR-155-5p and hsa-miR-28-5p represent sensitive molecular indicators of persistent inflammation and vascular dysfunction in Long COVID. Arterial hypertension is associated with dysregulation of these microRNAs, reflecting enhanced immune-mediated vascular activation. These findings support the importance of cardiovascular risk stratification and targeted follow-up strategies in Long COVID patients with hypertension-related vulnerability.
Agzamxodjayeva et al. (Fri,) studied this question.