Department of Optics, Faculty of Science.
Department of Physical Education and Sport, Faculty of Sport Sciences, University of Granada, Granada, Spain.
J Glaucoma. 2020 Jul;29(7):581-586. doi: 10.1097/IJG.0000000000001510.
PRéCIS:: Greater intraocular pressure (IOP) values are observed when reading in the supine position in comparison with the sitting position, and thus, it should be considered by eye care specialists for the management of glaucoma patients or those at risk.
IOP is sensitive to near work and body position, however, the influence of the body position adopted while performing near tasks remains unknown. This study aimed to assess the IOP changes induced by reading on a smartphone in sitting and supine position, and to explore whether these IOP changes differ between men and women.
Twenty-four healthy young adults (12 men and 12 women) read a text on a smartphone placed at 30 cm for 25 minutes while lying down and sitting in 2 different days. A rebound tonometer, which allows assessing IOP in the supine position, was used to measure IOP before reading, during reading (5, 15, and 25 min), and after 5 minutes of recovery. Complementarily, the authors checked the level of sleepiness/alertness before reading, and the perceived levels of fatigue and discomfort after reading.
The data showed that reading induces an IOP rise [P<0.001, partial eta squared (ηp)=0.44]. These effects were more accentuated when reading in the supine position in comparison with the sitting position (P=0.019, ηp=0.23) with an increment of 2.4 mm Hg (14%) and 1.3 mm Hg (8%) after 25 minutes of reading, respectively. The IOP rises associated with reading did not differ between men and women (P=0.127). Participants reported greater levels of discomfort in the neck and back when reading in the sitting position (P=0.012, ηp=0.25).
The IOP rises associated with reading are greater when it is performed in the supine position in comparison with the sitting position. The present findings indicate that reading in the supine position should be discouraged in individuals who should avoid IOP increments or fluctuations.
阅读时眼压（IOP）值在仰卧位比坐位高，因此，眼科专家在管理青光眼患者或有风险的患者时应考虑这一因素。
IOP 对近距工作和体位敏感，但进行近距任务时所采用的体位对 IOP 的影响尚不清楚。本研究旨在评估仰卧位和坐位阅读对智能手机时IOP 的影响，并探讨这些 IOP 变化是否存在性别差异。
24 名健康年轻成年人（12 名男性和 12 名女性）在 2 天内分别仰卧位和坐位阅读智能手机上的文本 25 分钟，阅读距离为 30cm。使用回弹眼压计测量阅读前、阅读时（5、15 和 25 分钟）和恢复后 5 分钟的 IOP。此外，作者在阅读前检查了困倦/警觉程度，以及阅读后疲劳和不适的感知程度。
数据显示阅读会引起 IOP 升高（P<0.001，部分 eta 平方（ηp）=0.44）。与坐位相比，仰卧位阅读时这些影响更为明显（P=0.019，ηp=0.23），分别在 25 分钟阅读后增加 2.4mmHg（14%）和 1.3mmHg（8%）。男性和女性之间阅读引起的 IOP 升高没有差异（P=0.127）。参与者报告在坐位阅读时颈部和背部的不适感更明显（P=0.012，ηp=0.25）。
仰卧位阅读时与坐位相比，IOP 升高幅度更大。本研究结果表明，应避免仰卧位阅读，以防 IOP 升高或波动。
