Orthostatic blood pressure reduction is associated with renal damage in functionally preserved elderly hypertensive patients.

BACKGROUND

Blood pressure (BP) exhibits specific characteristics in elderly patients. We evaluated the association between positional BP changes during orthostatism and the presence of hypertension-mediated organ damage (HMOD) in functionally preserved elderly hypertensive patients.

METHODS

This was a multicenter, cross-sectional study of 156 hypertensive patients with a mean age of 75 ± 5.8 years (49% women). Central and peripheral office and 24-h BP were measured using an oscillometric device. Orthostatic BP changes were recorded according to the conventional definition of orthostatic hypotension (OH) and also as a continuous variable obtained by subtracting values (supine BP - orthostatic BP). Treating BP as a continuous variable, patients were divided into two groups based on orthostatic BP changes, below or above the median of the distribution. HMOD was assessed as renal (reduced glomerular filtration rate and/or increased albuminuria), cardiac [left ventricular hypertrophy (LVH)], and arterial (increased aortic pulse wave velocity).

RESULTS

OH was present in 33 patients (21%), whereas orthostatic BP change showed a wide distribution. A total of 145 patients (92.9%) presented HMOD (48% kidney disease, 47% LVH, and 81% arterial stiffness). All patients with OH showed HMOD involvement and significantly higher values of all systolic BP estimates. Although OH and HMOD were not significantly associated, analysis of orthostatic BP changes showed greater renal damage in the group with a BP reduction above the median compared with those with a reduction below it, after adjustment for age, office BP, and alpha-blocker treatment (p < 0.05).

CONCLUSION

Orthostatic BP reduction is associated with renal damage in functionally preserved elderly hypertensive patients.