Can Sleeping Position Affect Eye Pressure in Glaucoma?

Glaucoma is a condition in which damage to the optic nerve can lead to vision loss, and elevated eye pressure — called intraocular pressure (IOP) — is the most important modifiable risk factor doctors can currently treat. While medications and procedures are commonly used to lower IOP, researchers are also interested in whether everyday behaviors, such as sleeping position, might influence eye pressure — especially overnight, when IOP naturally tends to rise.

In the current study, published in the British Journal of Ophthalmology, investigators found that certain sleep positions may worsen nighttime eye pressure fluctuations, especially in patients with primary open-angle glaucoma. Posture-related compression of neck veins may help explain why some sleeping positions raise eye pressure in glaucoma patients.

“Traditional strategies of nocturnal IOP management are primarily limited to increasing the types and frequency of IOP-lowering medications or supplementary laser therapy,” wrote investigators. “Given the well-documented influence of postural changes on IOP, positional modification emerges as a plausible strategy warranting further investigation.”

The team examined whether sleeping with the head elevated on two pillows (a “high-pillow” position) affects eye pressure compared with lying flat on the back (the supine position). The study included 144 people with glaucoma, whose eye pressure was measured in both positions. The team also studied 20 healthy volunteers using ultrasound imaging to see how neck veins responded to these posture changes.

The results showed that compared with lying flat, the high-pillow position led to higher eye pressure, greater fluctuations in eye pressure over 24 hours, and lower ocular perfusion pressure (a measure related to blood flow to the eye). A total of 96 patients (66.7%) demonstrated elevated IOP when transitioning from the flat position to the high-pillow position.

Reduced blood flow to the optic nerve is concerning because it may contribute to glaucoma progression. These posture-related pressure changes were more pronounced in younger patients, those with primary open-angle glaucoma and people with thicker corneas.

Ultrasound imaging offered a possible explanation: When volunteers used the high-pillow position, the jugular veins in the neck became compressed, which altered blood flow. This compression may increase pressure in the veins that drain blood from the eye, indirectly raising eye pressure.

Investigators noted the study had some limitations, including a relatively small number of participants in certain types of glaucoma and natural variation in eye pressure changes between individuals. Even so, the main finding (that sleeping with the head elevated on two pillows can raise eye pressure) was consistent and reliable. The team used a realistic sleep setup rather than strict positioning rules to better reflect how people actually sleep at home, which makes the results more relevant to everyday life.

Overall, the findings suggest that sleeping with the head elevated using multiple pillows may unintentionally raise eye pressure in people with glaucoma. While more research is needed before making firm recommendations, the study raises the possibility that avoiding sleep positions that compress neck veins could help reduce nighttime eye pressure fluctuations as a supportive strategy alongside standard glaucoma treatments.

“Patients with glaucoma may therefore benefit from avoiding sleeping postures that induce jugular venous compression to mitigate postural IOP elevation,” concluded investigators. “Such behavioral adjustments represent a simple yet potentially effective adjunctive strategy for optimizing long-term IOP management in clinical practice.”