Posture-induced intraocular pressure changes among patients with primary open angle glaucoma in a Nigerian Tertiary Hospital: Any implication for management.

Background And Aim: To determine the effect of postural changes on intraocular pressure (IOP) among newly diagnosed patients with primary open-angle glaucoma (POAG).

Patients And Methods: This was a cross-sectional observational study of 55 consecutive newly diagnosed patients with POAG attending Glaucoma clinics at a Federal Teaching Hospital in Abakaliki, Ebonyi state, from July to September 2017. Patients IOPs were measured in the sitting position, supine without a pillow, and supine with pillow positions using Perkin's handheld applanation tonometer. All data were analyzed with SPSS version 20.0.

Results: A total of 55 subjects were recruited comprising 30 (54.5%) males and 25 (45.5%) females, with a mean age of 50.13 ± 9.97 years and an age range of 30-79 years. The mean intraocular pressure was 27.54 ± 3.98 mmHg in the sitting position, 30.15 ± 4.41 mmHg in the supine with pillow position, and 35.22 ± 4.61 mmHg in the supine without pillow position. The mean difference of mean IOP of sitting compared to supine without the pillow was 7.68 ± 2.08 mmHg (P-value < 0.001, 95% CI: 7.12-8.24); sitting compared to supine with the pillow was 2.61 ± 1.49 mmHg (P-value < 0.001, 95% CI: 3.01-2.21), whereas supine without the pillow compared to supine with the pillow was 5.07 ± 2.24 mmHg (P-value 0.001, 95% CI: 4.47-5.68).

Conclusion: IOP was lowest in the sitting position and highest in the supine without pillow position. There was a statistically significant reduction in IOP on the assumption of supine with pillow position compared to supine without pillow position. The use of thick pillows in supine positions (such as during sleep or relaxations) rather than lying supine without pillows may reduce IOP spikes in POAG patients. This may have a positive effect as regards treatment and progression of glaucoma.