HEAD ELEVATION AND GLAUCOMA

Several nighttime events including increased IOP, decreased ocular perfusion pressure (OPP), and possibly obstructive sleep apnea (OSA) contribute to the development and progression of glaucomatous optic neuropathy. These events may explain the occurrence and progression of glaucomatous disease in the setting of seemingly controlled office-measured IOP. [1]

A study by Buys et al., has shown the 30-degree head-up sleeping position lowers IOP compared with the flat position. Although this effect varies between individual patients, mean IOP was 20% lower in one third of patients in this series.[2]

Several studies have shown that raising the bed head by 30-degrees significantly lowers IOP compared to the supine position. However, the method applied to elevate the head plays a significant role in IOP reduction. For example, while bed head elevation (BHE) is useful, resting on multiple pillows (MP) does not appear to offer the same IOP reduction in glaucoma patients.[3]

Some researchers studied the effect of sleeping in a head-up position using a wedge pillow in glaucoma patients, and healthy subjects. They have demonstrated reduction of mean IOP by 1.5–3.2 mm Hg in the head-up position compared with the flat position.[3]

Lazzaro et al also studied the effect of sleeping in a 20° head-up position in 15 glaucoma patients and 15 non-glaucoma patients. They demonstrated lower nocturnal IOPs (−1.5 mm Hg) with head-up position as compared with the head-flat position in patients with and without glaucoma.[4]

However, Natasha G reported that lying down increases IOP but also improves ocular blood flow. This could affect progression of glaucomatous optic nerve degeneration.[5]

REFERENCES:

1. Aref AA. What happens to glaucoma patients during sleep? Curr Opin Ophthalmol. 2013 Mar;24(2):162-6.
2. Buys YM, Alasbali T, Jin YP, Smith M, Gouws P, Geffen N, Flanagan JG, Shapiro CM, Trope GE. Effect of sleeping in a head-up position on intraocular pressure in patients with glaucoma. Ophthalmology. 2010 Jul;117(7):1348-51.
3. Yeon DY, Yoo C, Lee TE, Park JH, Kim YY. Effects of head elevation on intraocular pressure in healthy subjects: raising bed head vs using multiple pillows. Eye (Lond). 2014 Nov;28(11):1328-33. 
4. Lazzaro EC, Mallick A, Singh M, Reich I, Elmann S, Stefanov DG, et al. The effect of positional changes on intraocular pressure during sleep in patients with and without glaucoma. J Glaucoma. 2014;23:282–287.
5. https://www.medscape.com/viewarticle/night-shift-should-patients-glaucoma-sleep-their-head-raised-2025a10005rn