中国汉族人和美国高加索人眼前节结构差异的初步研究

Differences in anterior segment structure between Chinese Han people and American Caucasians

目的 比较中国汉族人和美国高加索人眼前节结构的差异,并探索影响前房角参数的相关因素.方法 横断面研究.研究设计自2008年5月到2010年12月纳人中国汉族人(从北京大学第三医院眼科招募)和美国高加索人(从美国加州大学旧金山分校眼科门诊招募)2组健康人群,每组纳入120名志愿者,年龄40~80岁,每隔10岁纳入30名,其中男、女各15名.应用自动屈光检查仪、A超、超声生物显微镜测量眼前节参数.两组间连续变量的比较采用独立样本t检验或Wilcoxon秩和检验,分类变量的比较采用x2检验,采用多元线性回归方法分析前房角参数的影响因素.结果 共纳人中国汉族人118名(118只眼)和美国高加索人117名(117只眼).与高加索人相比,汉族人有较小的A超测量前房深度[(3.03±0.34) mm与(3.38±0.36) mm比较,t=-5.791]、晶状体相对位置[0.227 (0.198,0.256)与0.235 (0.191,0.262)比较,Z=-3.063]、眼轴长度[23.3 (20.9,28.3) mm与24.2 (20.8,28.5) mm比较,Z=-5.510]、虹膜根部附着点距离[0.111(0.000,0.401)mm与0.142(0.000,0.451)mm比较,Z=-3.188]、巩膜突后1 mm处睫状体厚度[0.661(0.424,0.892)mm与0.716(0.467,0.942)mm比较,Z=-3.456]、小梁睫状突距离[0.780(0.410,1.400) mm与0.930(0.420,1.470) mm比较,Z=-3.191]、小梁睫状突夹角[73.4°(36.3°,115.3°)与81.1°(47.9°,147.9°)比较,Z=-3.407]、前房角开放距离500(AOD500)[0.181 (0.000,0.703)mm与0.264(0.000,0.806)mm比较,Z=-3.444]和房角隐窝面积(ARA) [0.118(0.011,0.457)mm2与0.179(0.000,0.626)mm2比较,Z=-3.814](均P<0.01);与高加索人相比,汉族人有较大的等效球镜屈光度[0.40(-5.80,4.00)D与-0.70(-8.00,4.00)D比较,Z=-5.454]、晶状体厚度[(4.62±0.40) mm与(4.52±0.40) mm比较,t=2.077]和虹膜厚度[0.430 (0.280,0.600)mm与0.410(0.240,0.580)mm比较,Z=-2.263](均P<0.05).总体上,年龄每增加10岁,汉族人的AOD500比高加索人减小更快(汉族人0.040 mm,高加索人0.030 mm),而ARA减小速度相同(两组均为0.020 mm2).经校正年龄、性别、等效球镜屈光度、眼轴长度以及其他眼前节参数后,汉族人和高加索人前房角参数的最主要影响因素分别为小梁睫状突夹角(AOD500的标准化回归系数为0.487,R2=0.549;ARA的标准化回归系数为0.372,R2=0.502)和前房深度(AOD500的标准化回归系数为0.413,R2=0.476;ARA的标准化回归系数为0.331,R2=0.403)(均P<0.001).结论 与年龄和性别匹配的美国高加索人相比,中国汉族人有更加拥挤的前房和更加狭窄的前房角,老龄化对中国汉族人的前房角狭窄影响更加明显.睫状体前位程度和前房深度分别是影响中国汉族人和美国高加索人前房角的主要因素.

Objective To compare the difference of anterior segment structure between Chinese Han people and American Caucasians,and to explore the confounding factors of anterior chamber angle.Methods Cross-sectional study.The study was designed to include two healthy groups of Chinese Han people (enrolled from Department of Ophthalmology,Peking University Third Hospital) and American Caucasians (enrolled from Department of Ophthalmology,University of California,San Francisco) from May 2008 to December 2010,each with approximately 120 participants,including 15 persons of each gender in each decade between 40 and 80 years of age.The parameters of the anterior segment were measured by the automatic refractive test,A-ultrasound and ultrasound biomicroscopy.Differences between the two groups were compared with the independent-sample t test or Wilcoxon two-sample test for continuous variable data and the x2 test for classified variable data.Multiple linear regression models were performed to analyze the associated factors of anterior chamber angle.Results There were 118 subjects (118 eyes) and 117 subjects (117 eyes) enrolled in the Chinese and American Caucasians groups,respectively.Compared to Caucasians,Chinese had smaller A-ultrasound measured anterior chamber depth [(3.03±0.34) mm vs.(3.38±0.36) mm,t=-5.791,P<0.001],smaller relative lens position [0.227 (0.198,0.256) vs.0.235 (0.191,0.262),Z=-3.063,P =0.002],smaller axial length [23.3 (20.9,28.3) mm vs.24.2 (20.8,28.5) mm,Z=-5.510,P<0.001],smaller iris root distance [0.111 (0.000,0.401) mm vs.0.142 (0.000,0.451) mm,Z=-3.188,P=0.001],smaller ciliary body thickness at 1 mm posterior to the scleral spur [0.661 (0.424,0.892) mm vs.0.716 (0.467,0.942) mm,Z=-3.456,P=0.001],smaller trabecular ciliary process distance [0.780 (0.410,1.400) mm vs.0.930 (0.420,1.470) mm,Z=3.191,P=0.001],smaller trabecular ciliary process angle [73.4°(36.3°,115.3°) vs.81.1° (47.9°,147.9°),Z=-3.407,P =0.001],smaller angle opening distance at 500 μm (AOD500) [0.181 (0.000,0.703) mm vs.0.264 (0.000,0.806) mm,Z=-3.444,P=0.001],smaller angle recess area (ARA) [0.118 (0.011,0.457) mm2 vs.0.179 (0.000,0.626) mm2,Z=-3.814,P<0.001],larger spherical equivalent [0.40 (-5.80,4.00) D vs.-0.70 (-8.00,4.00) D,Z=-5.454,P<0.001],larger lens thickness [(4.62±0.40) mm vs.(4.52± 0.40) mm,t=2.077,P=0.039] and larger iris thickness [0.430 (0.280,0.600) mm vs.0.410 (0.240,0.580) mm,Z=-2.263,P=0.024].On average,with each decade of the increased age,Chinese had a greater decrease in the AOD500 than Caucasians (0.040 mm in Chinese vs.0.030 mm in Caucasians),while the angle recess area decreased at the same rate (0.020 mm2 in both groups).After adjusted for age,gender,spherical equivalent,axial length and other parameters of the anterior segment,the trabecular ciliary process angle [for AOD500,standardized regression coefficient (SRC)=0.487,R2=0.549,P<0.001;for ARA,SRC=0.372,R2=0.502,P<0.001] and anterior chamber depth (for AOD500,SRC=0.413,R2=0.476,P<0.001;for ARA,SRC=0.331,R2=0.403,P<0.001) were the main factors of anterior chamber angle parameters for Chinese and Caucasians,respectively.Conclusions Compared with age and gender matched American Caucasians,Chinese Han people have more crowded anterior chambers and narrower anterior chamber angles.The more anteriorly positioned ciliary processes and shallower anterior chambers are the main factors that contributed to more crowded anterior chambers in Chinese Han people and American Caucasians,respectively.