Prevalence and Etiology of Delayed Orthostatic Hypotension in Adult Women

A representative SBP and DBP profile obtained by continuous blood pressure monitoring during 30 minutes of quiet sitting from a (A) normotensive subject and (B) delayed OH subject.

The mean resting DBP of the study population 2 minutes, 15 minutes, and 30 minutes after sitting. The normotensive group (n=21) exhibited a significant increase in DBP (P=.001) during 30 minutes of quiet upright sitting (71.1±1.0mmHg) in comparison to the 15-minute time point (64.2±0.9mmHg). The delayed OH group (n=9) experienced a significant decrease in resting DBP (53.1±0.9mmHg, P=.02) compared with the 15-minute time point (59.8±0.4mmHg).

The venous-filling index and calf venous volume for all study subjects. The venous-filling index was in the normative range (≤5mL/s) for all the subjects, as was calf venous volume (20–80mL). Legend: •, delayed OH group; ○, normotensive group.

Peripheral edema (index of microvascular filtration) and venous ejection fraction after 30 minutes of upright sitting. Six subjects (4 from the normotensive group; 2 delayed OH group) had an ejection fraction less than 30%. Four normotensive subjects showed higher peripheral edema rate than any of the delayed OH subjects. Legend: •, delayed OH group; ○, normotensive group.

Effect of 30 minutes of plantar micromechanical stimulation on both SBP and DBP of 9 subjects in the delayed OH group. Both SBP (P=.003) and DBP (P=.002) values were significantly increased because of stimulation in comparison to values observed after 30 minutes of quiet upright sitting. Legend: ☐, blood pressure after 30 minutes of upright sitting; ○, blood pressure values after 30 minutes of plantar-based stimulation.