Sasaki H, Jonasson F, Kojima M, Katoh N, Ono M, Takahashi N, Sasaki K
Department of Ophthalmology, University of Iceland, Reykjavik, Iceland.
Ophthalmologica. 2000;214(6):412-20. doi: 10.1159/000027535.
A population-based cataract epidemiological study, the Reykjavik Eye Study, was conducted to determine the prevalence and characteristics of lens opacities in Iceland. The results were compared with those from previous surveys in Japan to determine the influence of race and environmental factors.
1,635 randomly selected residents of Reykjavik, Iceland, were enrolled, and among them, 1,045 responded and took part in the study. The subjects received ophthalmological examination of both the anterior and the posterior segments. Changes in the crystalline lens were examined and photographed under maximal pupillary dilation. Classification of the opacity types and grading of the extent of lens opacificiation were done using a standardized scheme, and the data were analyzed with Student's test, the chi(2) test and the Mantel-Haenszel test.
The prevalence of lens opacities in subjects in their 50s, 60s, 70s and in those 80 years and older was 42.7, 61.0, 85.3 and 100%, respectively. Grade II and III lens opacities were found in 2. 2% of subjects in their 50s and in 10.5, 35.9 and 62.3% in their 60s, 70s, and over 80 years, respectively. Cortical opacities predominated in all age groups followed by nuclear opacities; subcapsular opacities, on the other hand, were quite rare. A unique type of opacity, i.e., granular opacity, seldom seen among the Japanese, was found in 6.6% of the Icelandic subjects.
Our results show that cortical opacity is the major type of opacity in Icelandic subjects, although its prevalence was lower than that in the Japanese subjects. Interestingly, the first appearance of lens opacities of grades II and III in Icelanders was delayed by 10 years compared to the Japanese suggesting fewer or less severe risk factors for cataract formation in Iceland.
开展一项基于人群的白内障流行病学研究——雷克雅未克眼病研究，以确定冰岛晶状体混浊的患病率及特征。将研究结果与日本此前的调查结果进行比较，以确定种族和环境因素的影响。
随机选取1635名冰岛雷克雅未克居民参与研究，其中1045人作出回应并参与了该研究。研究对象接受了眼前节和眼后节的眼科检查。在最大瞳孔散大状态下检查并拍摄晶状体的变化情况。采用标准化方案对混浊类型进行分类并对晶状体混浊程度进行分级，数据采用学生检验、卡方检验和曼特尔 - 亨塞尔检验进行分析。
50多岁、60多岁、70多岁以及80岁及以上研究对象的晶状体混浊患病率分别为42.7%、61.0%、85.3%和100%。50多岁的研究对象中，II级和III级晶状体混浊的比例为2.2%，而60多岁、70多岁以及80岁以上的研究对象中该比例分别为10.5%、35.9%和62.3%。所有年龄组中均以皮质性混浊为主，其次为核性混浊；而囊下混浊则相当少见。一种在日本人中很少见的独特混浊类型，即颗粒状混浊，在6.6%的冰岛研究对象中被发现。
我们的研究结果表明，皮质性混浊是冰岛研究对象中主要的混浊类型，尽管其患病率低于日本研究对象。有趣的是，与日本人相比，冰岛人II级和III级晶状体混浊的首次出现延迟了10年，这表明冰岛白内障形成的危险因素较少或不太严重。
