The Impact of Head-Up Tilt Sleeping on Orthostatic Tolerance: A Scoping Review

Figures

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  Figure 1. PRISMA flow diagram. HUTS = head-up tilt sleeping; PRISMA = preferred reporting items for systematic reviews and meta-analyses [28].

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  Figure 2. Illustration of the different angles of HUTS applied in the included studies. The number of cases subjected to the specific angles are indicated.

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  Figure 3. Forest plot showing mean differences and 95% confidence intervals of orthostatic systolic blood pressure (SBP) values (i.e., standing and change upon standing) after and before head-up tilt sleeping intervention (HUTS) in studies with orthostatic hypotension (n = 6; 102 cases). Favouring HUTS (towards the right) is a higher standing BP and smaller drop post HUTS, shown as the increase in the SBP change. Many of the included studies had a very limited sample size, resulting in unreliable estimations of the mean and confidence interval and a high likelihood of type II errors. In the case series, we only calculated the mean difference if we had access to the data of at least two cases [26,27]. * Values corresponding to this study: 95% CI—130 to 162 mmHg. SBP = systolic blood pressure; HUTS = head-up tilted sleeping.