Rahmani B, Tielsch J M, Katz J, Gottsch J, Quigley H, Javitt J, Sommer A
Dana Center for Preventive Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, USA.
Ophthalmology. 1996 Nov;103(11):1721-6. doi: 10.1016/s0161-6420(96)30435-1.
Whereas population-based data on the causes of bilateral blindness have been reported, little information is available on the distribution of causes of central vision loss less severe than the criteria used to define legal blindness. This visual impairment is responsible for a high proportion of eye care service use and results in important reductions in functional status.
Data from the Baltimore Eye Survey were used to estimate the cause-specific prevalence of visual impairment (best-corrected visual acuity worse than 20/40 but better than 20/200) among black and white residents of east Baltimore who were 40 years of age or older. Eligible subjects underwent a screening examination at a neighborhood location and, for those whose best-corrected visual acuity was less than 20/30, a definitive ophthalmologic examination at the Wilmer Eye Institute.
The prevalence of visual impairment was 2.7% in whites and 3.3% in blacks; the age-adjusted relative prevalence (B/W) was 1.75 (P = 0.01). The leading causes of visual impaired eyes were cataract (35.8%), age-related macular degeneration (14.2%), diabetic retinopathy (6.6%), glaucoma (4.7%), and other retinal disorders (7.3%). Cataract, diabetic retinopathy, and glaucoma were more common as a cause of visual impairment among blacks, whereas macular degeneration was more frequent among whites. More than 50% of all subjects had the potential for improvement in vision with appropriate surgical intervention.
Visual impairment is a prevalent condition among inner city adults 40 years of age or older. The distribution of causes suggests that improvements in the visual health of the population could be achieved with more effective delivery of efficacious ophthalmologic care.
尽管已有基于人群的双侧失明病因数据报道，但关于比法定失明定义标准程度较轻的中心视力丧失病因分布的信息却很少。这种视力损害导致了很大一部分眼科护理服务的使用，并导致功能状态显著下降。
巴尔的摩眼病调查数据用于估计巴尔的摩东部40岁及以上黑人和白人居民中特定病因的视力损害患病率（最佳矫正视力低于20/40但优于20/200）。符合条件的受试者在社区地点接受筛查检查，对于最佳矫正视力低于20/30的受试者，在威尔默眼科研究所进行确定性眼科检查。
白人视力损害患病率为2.7%，黑人为3.3%；年龄调整后的相对患病率（黑人/白人）为1.75（P = 0.01）。视力受损眼睛的主要病因是白内障（35.8%）、年龄相关性黄斑变性（14.2%）、糖尿病视网膜病变（6.6%）、青光眼（4.7%）和其他视网膜疾病（7.3%）。白内障、糖尿病视网膜病变和青光眼作为视力损害病因在黑人中更为常见，而黄斑变性在白人中更为常见。超过50%的受试者通过适当的手术干预有可能改善视力。
视力损害在40岁及以上的市中心成年人中是一种普遍存在的情况。病因分布表明，通过更有效地提供有效的眼科护理，可以改善人群的视觉健康。
