Objective:

This study aimed to identify optimal blood pressure cut-offs to diagnose orthostatic hypotension during a sit-to-stand manoeuvre.

Methods:

This was a cross-sectional study of patients and healthy controls from the Vanderbilt Autonomic Dysfunction Center. Blood pressure was measured while supine, seated and standing. Blood pressure changes were calculated from supine-to-standing and seated-to-standing. Orthostatic hypotension was diagnosed on the basis of a supine-to-standing SBP drop at least 20 mmHg or a DBP drop at least 10 mmHg. Receiver operator characteristic (ROC) curves identified optimal sit-to-stand cut-offs.

Results:

Amongst the 831 individuals, more had systolic orthostatic hypotension [n= 354 (43%)] than diastolic orthostatic hypotension [n= 305 (37%)] during lying-to-standing. The ROC curves had good characteristics [SBP area under curve= 0.916 (95% confidence interval: 0.896–0.936), P< 0.001; DBP area under curve= 0.930 (95% confidence interval: 0.909–0.950), P< 0.001]. A sit-to stand SBP drop at least 15 mmHg had optimal test characteristics (sensitivity= 80.2%; specificity= 88.9%; positive predictive value= 84.2%; negative predictive value= 85.8%), as did a DBP drop at least 7 mmHg (sensitivity= 87.2%; specificity= 87.2%; positive predictive value= 80.1%; negative predictive value= 92.0%).

Conclusions:

A sit-to-stand manoeuvre with lower diagnostic cut-offs for orthostatic hypotension provides a simple screening test for orthostatic hypotension in situations wherein a supine-to-standing manoeuvre cannot be easily performed. Our analysis suggests that a SBP drop at least 15 mmHg or a DBP drop at least 7 mmHg best optimizes sensitivity and specificity of this sit-to-stand test.