Bountziouka Vasiliki, Cumberland Phillippa M, Rahi Jugnoo S
Life Course Epidemiology and Biostatistics Section, Population, Policy, and Practice Programme, University College London Great Ormond Street Institute of Child Health, London, England.
Ulverscroft Vision Research Group, London, England.
JAMA Ophthalmol. 2017 Sep 1;135(9):954-961. doi: 10.1001/jamaophthalmol.2017.2812.
Despite the existing country-specific strategies tackling social inequalities in visual health in adults, little is known about trends in visual function in childhood and its association with social position.
To investigate the distribution of childhood visual function in the United Kingdom and associations with early-life social position between 1961 and 1986, a period of significant social change.
DESIGN, SETTING, AND PARTICIPANTS: Longitudinal cohort study using harmonized data sets from the British 1946, 1958, and 1970 national birth cohorts. In total, 14 283 cohort members with complete data on visual acuity at age 15 or 16 years, measured in 1961, 1974, and 1986, respectively, for each cohort, and social position were assessed.
Using habitual distance visual acuity (with correction if prescribed), participants were assigned to a visual function category ranging from bilateral normal to visual impairment/severe visual impairment/blindness (International Statistical Classification of Diseases, Tenth Revision, Clinical Modification). Distribution of visual function over time and associations with social position (risk ratios [RRs] and 95% confidence intervals) were analyzed.
Complete data were available for 3152 participants (aged 15 years; 53% boys [n = 1660]) in the 1946 Medical Research Council National Survey of Health and Development, 6683 participants (aged 16 years; 51% boys [n = 3420]) in the 1958 National Child Development Study, and 4448 participants (aged 16 years; 48% boys [n = 2156]) in the 1970 British Birth Cohort Study. The proportion of children with bilateral normal vision decreased by 1.3% (95% CI, -5.1% to 2.7%) in 1974 and 1.7% (95% CI, -5.9% to 2.7%) in 1986. The risk of overall impaired vision increased by 1.20 times (95% CI, 1.01-1.43) and the risk of visual impairment/severe visual impairment/blindness by 1.75 times (95% CI, 1.03-2.98) during this period. Girls were consistently at increased risk of all vision impairment categories. Higher social position at birth and in childhood was associated with reduced risk of visual impairment/severe visual impairment/blindness (RR, 0.58; 95% CI, 0.20-1.68) and unilateral impairment (RR, 0.89; 95% CI, 0.72-1.11), respectively.
Our study provides evidence of temporal decline in childhood visual function between 1961 and 1986. Despite the limited power of the analysis owing to the small sample size of those with impaired vision, we found an emergence of a contribution of sociodemographic status to the cohort effect that may be the antecedent of the current picture of childhood blindness. Equally, early-life social position may also have contributed to the current social patterning in visual function in older adults in the United Kingdom. These findings highlight the potential value of targeting children in national ophthalmic public policies tackling inequalities.
尽管已有针对各国成年人视觉健康方面社会不平等问题的特定战略，但对于儿童视觉功能的趋势及其与社会地位的关联却知之甚少。
调查1961年至1986年期间英国儿童视觉功能的分布情况以及与早期社会地位的关联，这是一个社会发生重大变革的时期。
设计、背景和参与者：纵向队列研究，使用来自英国1946年、1958年和1970年全国出生队列的统一数据集。总共评估了14283名队列成员，他们分别在各队列对应的1961年、1974年和1986年有15或16岁时的完整视力数据，以及社会地位数据。
使用习惯远距离视力（必要时进行矫正），将参与者分配到从双眼正常到视力损害/严重视力损害/失明（《疾病和有关健康问题的国际统计分类》第十次修订本，临床修订版）的视觉功能类别。分析视觉功能随时间的分布情况以及与社会地位的关联（风险比[RRs]和95%置信区间）。
在1946年医学研究理事会全国健康与发展调查中有3152名参与者（15岁；53%为男孩[n = 1660]）、1958年全国儿童发展研究中有6683名参与者（16岁；51%为男孩[n = 3420]）以及1970年英国出生队列研究中有4448名参与者（16岁；48%为男孩[n = 2156]）可获得完整数据。1974年双眼正常视力儿童的比例下降了1.3%（95%置信区间，-5.1%至2.7%），1986年下降了1.7%（95%置信区间，-5.9%至2.7%）。在此期间，总体视力受损风险增加了1.20倍（95%置信区间，1.01 - 1.43），视力损害/严重视力损害/失明风险增加了1.75倍（95%置信区间，1.03 - 2.98）。女孩在所有视力损害类别中的风险一直较高。出生时和儿童期较高的社会地位分别与视力损害/严重视力损害/失明风险降低（RR，0.58；95%置信区间，0.20 - 1.68）和单眼损害风险降低（RR，0.89；95%置信区间，0.72 - 1.11）相关。
我们的研究提供了1961年至1986年期间英国儿童视觉功能随时间下降的证据。尽管由于视力受损者样本量小导致分析效力有限，但我们发现社会人口学状况对队列效应有影响，这可能是当前儿童失明状况的先兆。同样，早期社会地位可能也对英国老年人当前视觉功能的社会模式产生了影响。这些发现凸显了在解决不平等问题的国家眼科公共政策中以儿童为目标的潜在价值。
