Orthostatic Hypertension: Clinical Spectrum and Gaps in Knowledge.

PURPOSE OF REVIEW: Orthostatic hypertension (oHT) is increasingly recognized as a clinically relevant but poorly understood disorder of autonomic blood pressure control. This review aims to summarize the current understanding of the clinical spectrum and pathophysiology of oHT, evaluate its prognostic significance, and identify key gaps in knowledge to guide future mechanistic and clinical studies. RECENT FINDINGS: Recent evidence has shifted the perception of oHT from a physiological variant to a condition associated with adverse outcomes. In younger adults, oHT has been linked to incident hypertension, while in older populations it is associated with cardiovascular, cerebrovascular, renal, and cognitive complications. Excessive sympathetically mediated vasoconstriction appears to be the predominant mechanism, although arterial stiffness, impaired baroreflex buffering, and abnormal vascular responsiveness may also contribute depending on the population. Consensus definitions have recently standardized diagnostic criteria, but uncertainties remain regarding optimal thresholds, measurement reproducibility, and the mechanisms underlying its heterogeneous presentation. Despite growing recognition, important questions remain regarding whether oHT represents an independent cardiovascular risk factor or primarily a marker of vascular aging and hypertension. Evidence supporting oHT-specific therapeutic strategies is currently lacking. Further research is needed to clarify its pathophysiology, refine diagnostic approaches, and determine its clinical and prognostic significance.