New England College of Optometry, Boston, Massachusetts.
Invest Ophthalmol Vis Sci. 2014 Feb 4;55(2):752-8. doi: 10.1167/iovs.13-13029.
To investigate monthly and seasonal variations in the progression of myopia in children enrolled in the Correction of Myopia Evaluation Trial (COMET).
An ethnically diverse cohort of 469 myopic 6- to <12 year-old children was randomized to single vision or progressive addition lenses and followed for 3 years with 98.5% retention. Progression of myopia was measured semiannually by noncycloplegic autorefraction (Nidek ARK 700A) and annually by cycloplegic autorefraction, with the former measurements used in these analyses. The semiannual progression rate was calculated as (change in spherical equivalent refraction between two consecutive semiannual visits/number of days between the two visits) times 182.5. Months were categorized as the midpoint between two visit dates. Seasons were classified as winter (October through March) or summer (April through September). The seasonal difference was tested using a linear mixed model adjusting for demographic variables (age, sex, ethnicity), baseline refraction, and treatment group.
Data from 358 children (mean [± SD] age = 9.84 ± 1.27 years; mean myopia = -2.54 ± 0.84 diopters [D]) met the criteria for these analyses. Myopia progression varied systematically by month; it was slower in April through September than in the other months. Mean progression in winter was -0.35 ± 0.34 D and in summer was -0.14 ± 0.32 D, a statistically significant difference (0.21 D, P < 0.0001). The same seasonal pattern was found by age, sex, ethnicity (except in the small sample of Asians), lens type, and clinical center.
The slower progression of myopia found in summer is likely related to children's spending more time outdoors and fewer hours in school. The data have clinical implications regarding the time of year and the frequency with which myopic children have eye examinations and the need for precise timing of visits in clinical trials testing new myopia treatments. (ClinicalTrials.gov number, NCT00000113.).
研究参加近视矫正评估试验（COMET）的儿童近视进展的月度和季节性变化。
对 469 名 6 至 <12 岁的近视程度不同的儿童进行了种族多样化的研究，将他们随机分为单视或渐进式附加镜片组，并进行了 3 年的随访，其中 98.5%的儿童得到了保留。近视进展通过非睫状肌麻痹自动折射（Nidek ARK 700A）半年度测量，以及每年通过睫状肌麻痹自动折射测量。这些分析中使用了前者的测量值。半年度进展率的计算方法为（两次半年度随访之间的等效球镜屈光度变化/两次随访之间的天数）乘以 182.5。月份被归类为两次就诊日期之间的中点。季节分为冬季（10 月至 3 月）和夏季（4 月至 9 月）。使用线性混合模型调整人口统计学变量（年龄、性别、种族）、基线折射和治疗组来测试季节性差异。
符合这些分析标准的数据来自 358 名儿童（平均[±SD]年龄=9.84±1.27 岁；平均近视度=-2.54±0.84 屈光度[D]）。近视进展逐月呈系统变化，4 月至 9 月较慢。冬季平均进展为-0.35±0.34 D，夏季为-0.14±0.32 D，差异具有统计学意义（0.21 D，P<0.0001）。在不同的年龄、性别、种族（亚洲样本较小的除外）、镜片类型和临床中心也发现了相同的季节性模式。
夏季发现的近视进展较慢可能与儿童户外活动时间增多、在校时间减少有关。这些数据与儿童每年进行眼部检查的时间和频率以及临床试验中测试新近视治疗方法的访视时间的精确性有关。（临床试验.gov 编号，NCT00000113）。
