Intraocular Pressure Elevation during Lateral Body Posture in Side-sleeping Glaucoma Patients

SIGNIFICANCE In side-sleeping open-angle glaucoma (OAG) patients, eyes that showed progression exhibited a greater intraocular pressure (IOP) elevation when subjects were rested in the lateral decubitus (LD) posture on the ipsilateral side compared with those eyes that did not progress. PURPOSE The purposes of this study were to investigate whether lying in the LD position for an extended period affects IOP in side-sleeping patients with OAG when rested on their own pillow and to compare posture-induced IOP variations between eyes with recent glaucomatous progression and those without. METHODS Twenty-eight bilateral OAG patients who reported a preference for side sleeping were included. We measured IOP in both eyes, with the patient in the sitting and supine positions, 5 and 30 minutes after they had been in the right or left LD position (depending on their sleeping habits) and 5 minutes after they had returned to the supine position. While in the recumbent postures, the patients rested on their own pillows from home. The patients were divided into the correspondence and noncorrespondence subgroups, based on whether the laterality of the progressed eye corresponded with their habitual sleeping side. RESULTS The IOP of the lower-sided eye increased further (+1.6 ± 1.8 mmHg; P <.001) when the LD posture was maintained for an additional 25 minutes. Such time-dependent IOP elevation in the dependent eye was greater in patients whose LD posture corresponded with glaucoma progression (+2.5 ± 1.7 mmHg) than in those who showed no correspondence or no glaucoma progression (+1.0 ± 1.6 mmHg; P =.03). CONCLUSIONS Compared with nonprogressed eyes, progressed eyes exhibited a greater IOP elevation when the side-sleeping patients with OAG were rested in the LD posture on the ipsilateral side.