Fotedar Reena, Mitchell Paul, Burlutsky George, Wang Jie Jin
Department of Ophthalmology, University of Sydney (Centre for Vision Research, Westmead Millennium Institute, Westmead Hospital), Sydney, Australia.
Ophthalmology. 2008 Aug;115(8):1273-8, 1278.e1. doi: 10.1016/j.ophtha.2007.11.003. Epub 2008 Jan 25.
To examine 10-year changes and other influences on spherical equivalent refraction (SER) in older persons.
Prospective population-based study.
Three thousand six hundred fifty-four Blue Mountains Eye Study participants 49 or older at baseline (1992-1994) were observed after 5 years (2335; 75% of survivors) and 10 years (1952; 76% of survivors).
At each visit, subjective refraction was performed using modified Early Treatment Diabetic Retinopathy Study protocols. Spherical equivalent refraction was calculated as sphere + half cylinder power. Axial length was measured only at the 10-year examinations, using an IOL Master. Right phakic eyes with best-corrected visual acuity > 20/40 (n = 1340) at baseline and 10-year examinations were included.
Temporal refractive change.
Over the decade, a hyperopic shift was observed among persons <65 years old, and a myopic shift was associated with increasing age among older subjects, with gender-adjusted mean SER changes of 0.40, 0.33, -0.02, and -0.65 diopters (D) in persons with baseline ages 49 to 54, 55 to 64, 65 to 74 and > or = 75, respectively. Apart from age, myopic refractive change was strongly associated with baseline nuclear cataract; mean changes of -0.96 and 0.26 D were observed in eyes with and without nuclear cataract, respectively (P<0.001). A birth cohort effect on refraction was also observed. After adjusting for age and nuclear cataract, baseline refractive status (P = 0.58), education (P = 0.34), and diabetes (P = 0.16) were not associated with changing SER. A 10% increase in against-the-rule astigmatism was observed over the 10-year period. Axial length showed an age-related reduction in 10-year cross-sectional data, from a mean of 23.61 mm (95% confidence interval [CI], 23.50-23.73) in 59- to 64-year-olds to a mean of 23.15 mm (95% CI, 22.83-23.47) in > or = 85-year-olds. After adjusting for age, education, and nuclear cataract, axial length measured 10 years later was not associated with change in SER (P = 0.34).
This longitudinal study confirms a hyperopic shift in persons younger than 65 and a myopic shift for older ages. Although underlying causes for this age-related hyperopic shift are unknown, it does not appear related to axial length. The myopic shift, however, is most likely caused by increasing nuclear cataract.
研究老年人球镜等效屈光度（SER）的10年变化及其他影响因素。
基于人群的前瞻性研究。
3654名蓝山眼研究参与者，基线时（1992 - 1994年）年龄在49岁及以上，分别在5年（2335名；幸存者的75%）和10年（1952名；幸存者的76%）后进行观察。
每次就诊时，使用改良的糖尿病视网膜病变早期治疗研究方案进行主观验光。球镜等效屈光度计算为球镜度 + 柱镜度的一半。仅在10年检查时使用IOL Master测量眼轴长度。纳入基线和10年检查时最佳矫正视力>20/40的右眼有晶状体眼（n = 1340）。
随时间的屈光变化。
在这十年间，65岁以下人群出现远视性移位，而老年受试者中近视性移位与年龄增加有关，基线年龄为49至54岁、55至64岁、65至74岁和≥75岁的人群，经性别调整后的平均SER变化分别为0.40、0.33、 - 0.02和 - 0.65屈光度（D）。除年龄外，近视性屈光变化与基线核性白内障密切相关；有和无核性白内障的眼睛平均变化分别为 - 0.96 D和0.26 D（P<0.001）。还观察到出生队列对屈光的影响。在调整年龄和核性白内障后，基线屈光状态（P = 0.58）、教育程度（P = 0.34）和糖尿病（P = 0.16）与SER变化无关。在10年期间观察到逆规散光增加了10%。在10年的横断面数据中，眼轴长度显示出与年龄相关的缩短，从59至64岁人群的平均23.61 mm（95%置信区间[CI]，23.50 - 23.73）降至≥85岁人群的平均23.15 mm（95% CI，22.83 - 23.47）。在调整年龄、教育程度和核性白内障后，10年后测量的眼轴长度与SER变化无关（P = 0.34）。
这项纵向研究证实了65岁以下人群的远视性移位和老年人的近视性移位。尽管这种与年龄相关的远视性移位的潜在原因尚不清楚，但似乎与眼轴长度无关。然而，近视性移位很可能是由核性白内障增加所致。
