Chandrasekaran Sujatha, Cumming Robert G, Rochtchina Elena, Mitchell Paul
Centre for Vision Research, Department of Ophthalmology and Westmead Millennium Institute, University of Sydney, Westmead, Australia.
Ophthalmology. 2006 Mar;113(3):417-24. doi: 10.1016/j.ophtha.2005.10.050. Epub 2006 Feb 3.
To examine incident relationships between elevated intraocular pressure (IOP), open-angle glaucoma (OAG), and use of glaucoma medications with 5-year incident cataract.
Population-based cohort study.
The Australian Blue Mountains Eye Study examined 3654 participants > or =50 years old at baseline (82.4% response; 1992-1994); 2335 eligible participants were reexamined after 5 years (75.1% response; 1997-1999).
A detailed medical and ocular history, including current medications, was taken, and a comprehensive eye examination, including applanation tonometry, automated perimetry, and lens photography, was performed at each examination. The Wisconsin system was used to grade lens photographs in assessing incident nuclear, cortical, and posterior subcapsular cataract (PSC). Data from both eyes were assessed using generalized estimating equation analyses.
Elevated IOP was defined as > or =21 mmHg. Open-angle glaucoma was diagnosed from typical glaucomatous field loss with matching optic disc cupping, without reference to IOP. Subjects without OAG or secondary or angle-closure glaucoma with IOP > 21 mmHg in either eye were classified as having ocular hypertension (OH), as were non-OAG subjects with IOP < 22 mmHg using glaucoma medications. Wisconsin levels 4 to 5 were graded as nuclear cataract, at least 5% lens involvement was graded as cortical cataract, and any PSC defined its presence.
The 5-year incidence of nuclear cataract was 23.4% (592/2532), or 23.1% (574/2486) after excluding subjects using glaucoma medication. A marginally significant association was found for elevated IOP or OH at baseline and incident nuclear cataract (odds ratio [OR], 1.93 [95% confidence interval (CI), 0.97-3.89], and OR, 1.83 [95% CI, 0.96-3.48], respectively) in subjects not using glaucoma medications, after multivariate adjustment. Age- and gender-adjusted analyses showed similar but statistically significant associations. The association between elevated IOP or OH and nuclear cataract was significant in multivariate analyses (OR, 2.07 [95% CI, 1.04-3.12], and OR, 1.78 [95% CI, 1.05-3.01], respectively). Use of glaucoma medications was associated with nonsignificantly increased adjusted odds for incident nuclear cataract (OR, 1.90 [95% CI, 0.92-3.92]). No associations, however, were found with incident cortical cataract or PSC.
Elevated IOP may increase the risk of nuclear cataract, but not that of other types. The use of glaucoma medications could magnify this risk.
研究眼内压（IOP）升高、开角型青光眼（OAG）以及使用青光眼药物与5年新发白内障之间的关联。
基于人群的队列研究。
澳大利亚蓝山眼研究在基线时检查了3654名年龄≥50岁的参与者（应答率82.4%；1992 - 1994年）；5年后对2335名符合条件的参与者进行了复查（应答率75.1%；1997 - 1999年）。
每次检查时都采集详细的医学和眼部病史，包括当前用药情况，并进行全面的眼部检查，包括压平眼压测量、自动视野检查和晶状体摄影。使用威斯康星系统对晶状体照片进行分级，以评估新发核性、皮质性和后囊下白内障（PSC）。使用广义估计方程分析双眼的数据。
IOP升高定义为≥21 mmHg。开角型青光眼根据典型的青光眼性视野缺损及相应的视盘杯状凹陷进行诊断，不参考IOP。双眼IOP>21 mmHg且无OAG或继发性或闭角型青光眼的受试者被归类为高眼压症（OH），使用青光眼药物且IOP<22 mmHg的非OAG受试者也被归类为OH。威斯康星分级4至5级被评为核性白内障，晶状体受累至少5%被评为皮质性白内障，任何PSC均定义为存在PSC。
核性白内障的5年发病率为23.4%（592/2532），排除使用青光眼药物的受试者后为23.1%（574/2486）。在未使用青光眼药物的受试者中，多因素调整后发现基线时IOP升高或OH与新发核性白内障之间存在边缘显著关联（优势比[OR]分别为1.93[95%置信区间（CI），0.97 - 3.89]和OR 1.83[95%CI，0.96 - 3.48]）。年龄和性别调整分析显示了类似但具有统计学意义的关联。在多因素分析中，IOP升高或OH与核性白内障之间的关联显著（OR分别为2.07[95%CI，1.04 - 3.12]和OR 1.78[95%CI，1.05 - 3.01]）。使用青光眼药物与新发核性白内障的调整后优势比非显著增加相关（OR，1.90[95%CI，0.92 - 3.92]）。然而，未发现与新发皮质性白内障或PSC有关联。
IOP升高可能增加核性白内障风险，但不增加其他类型白内障风险。使用青光眼药物可能会放大这种风险。
