National Centre for Optics, Vision and Eye Care, Faculty of Health and Social Sciences, University of South-Eastern Norway, Kongsberg, Norway.
Stem-Cell and Brain Research Institute, INSERM U1208, Bron, France.
Invest Ophthalmol Vis Sci. 2022 Oct 3;63(11):20. doi: 10.1167/iovs.63.11.20.
To investigate the diurnal rhythms in the human eye in winter and summer in southeast Norway (latitude 60°N).
Eight measures (epochs) of intraocular pressure, ocular biometry, and optical coherence tomography were obtained from healthy participants (17-24 years of age) on a mid-winter's day (n = 35; 6 hours of daylight at solstice) and on a day the following summer (n = 24; 18 hours of daylight at solstice). Participants wore an activity monitor 7 days before measurements. The epochs were scheduled relative to the individual's habitual wake and sleep time: two in the day (morning and midday) and six in the evening (every hour until and 1 hour after sleep time). Saliva was collected for melatonin. A linear mixed-effects model was used to determine significant diurnal variations, and a sinusoid with a 24-hour period was fitted to the data with a nonlinear mixed-effects model to estimate rhythmic statistics.
All parameters underwent significant diurnal variation in winter and summer (P < 0.002). A 1-hour phase advance was observed for melatonin and ocular axial length in the summer (P < 0.001). The degree of change in axial length was associated with axial length phase advance (R2 = 0.81, P < 0.001) and choroidal thickening (R2 = 0.54, P < 0.001) in summer.
Diurnal rhythms in ocular biometry appear to be synchronized with melatonin secretion in both winter and summer, revealing seasonal variation of diurnal rhythms in young adult eyes. The association between axial length and seasonal changes in the phase relationships between ocular parameters and melatonin suggests a between-individual variation in adaptation to seasonal changes in ocular diurnal rhythms.
在挪威东南部（北纬 60°）的冬季和夏季研究人类眼睛的昼夜节律。
在仲冬（冬至，6 小时日光）和仲夏日（夏至，18 小时日光），从健康参与者（17-24 岁）中获得 8 次眼内压、眼部生物测量和光学相干断层扫描测量（n=35；n=24）。参与者在测量前 7 天佩戴活动监测器。根据个人的日常作息时间安排时段：白天两次（上午和中午），晚上六次（每小时一次，直到和睡眠后 1 小时）。收集唾液以测定褪黑素。采用线性混合效应模型确定显著的昼夜变化，并用非线性混合效应模型拟合 24 小时周期的正弦曲线，以估计节律统计数据。
所有参数在冬季和夏季均有显著的昼夜变化（P < 0.002）。在夏季，褪黑素和眼轴长度出现 1 小时的相位提前（P < 0.001）。眼轴长度的变化程度与眼轴长度相位提前（R2=0.81，P < 0.001）和夏季脉络膜增厚（R2=0.54，P < 0.001）相关。
在冬季和夏季，眼部生物测量的昼夜节律似乎与褪黑素分泌同步，揭示了年轻成年人眼睛昼夜节律的季节性变化。眼轴长度与眼参数和褪黑素之间相位关系的季节性变化之间的关系表明，个体之间适应眼部昼夜节律季节性变化的差异。
