ALB and hypertensive disorder: Restricted cubic spline analysis revealed an approximately linear positive association between the red cell distribution width-to-albumin ratio (RAR) and hypertension prevalence (Overall P < 0.001; Nonlinearity P = 0.874) (Fig. 2), Despite a non-significant nonlinearty test (P = 0.874), the threshold model suggested distinct associations below and above RAR = 3.4, warranting clinical attention to this cutoff.