Spectacles utilization and its impact on health-related quality of life among rural Chinese adolescents.

PURPOSE: The aims of the study were to assess the magnitude and predictors of the unmet need for spectacles utilization and to quantify its impact on health-related quality of life (HRQOL) among rural Chinese adolescents. METHODS: This school-based survey of 2346 grade-7 students (mean age: 13.8 years) was conducted in Southwestern China in 2016. Spectacles need was defined as uncorrected visual acuity (VA) of 20/40 or worse but correctable to 20/40 or better in the better-seeing eye, together with the presence of myopia of less than -0.5 diopters (D), hyperopia of more than +2.0 D, or astigmatism of more than 0.75 D in both eyes. The HRQOL was measured using self-reported versions of 23-item Pediatric Quality of Life Inventory Version 4.0 Generic Core Scales (PedsQL 4.0). RESULTS: Among 579 (24.7%) adolescents with an uncorrected VA of 20/40 or less, 483 (83.4%) needed vision corrections and 172 (35.6%) used them. Higher parental education levels (odds ratio (OR) = 2.73; 95% CI, 1.29-5.77), negative attitude regarding spectacles (OR = 0.49; 95% CI, 0.25-0.97), and poorer uncorrected VA (OR = 31.27; 95% CI, 3.76-260.23) were independent determinants for spectacles utilization. Adolescents not using spectacles had a lower HRQOL score compared to those using spectacles in terms of psychosocial health (65.91 vs. 70.59; P = 0.028), emotional health (56.85 vs. 63.24; P = 0.012), and social functioning (72.99 vs. 78.60; P = 0.036). CONCLUSIONS: The rate of spectacles utilization in rural China was low. Adolescents were not accustomed to use spectacles had a worse HRQOL score.

Refractive error in Chinese with type 2 diabetes and its association with glycaemic control.

BACKGROUND: The aim of this study was to determine the prevalence of refractive errors and their association with glycaemic control among adults with type 2 diabetes mellitus (T2DM) in eastern China. METHODS: A community-based survey, including 913 adults with T2DM aged 30 to 89 years, was conducted. Refractive error was assessed by autorefraction, after which subjective refraction was performed. Ocular biometric parameters were measured by non-contact partial coherence laser interferometry. Myopia was defined as spherical equivalent (SE) less than -0.50 dioptres (D), high myopia as SE less than -5.00 D, hyperopia as SE greater than 0.50 D and astigmatism as cylinder less than -0.50 D. RESULTS: After excluding participants who had undergone cataract surgery, 839 were included in the data analyses and 96.1 per cent were found to have refractive errors. The overall prevalences of myopia, high myopia, hyperopia and astigmatism were 28.2 per cent (95 per cent confidence interval [CI] 25.2-31.3), 6.3 per cent (95 per cent CI 4.7-8.0), 46.4 per cent (95 per cent CI 43.0-49.7) and 81.0 per cent (95 per cent CI 78.4-83.7) with no gender differences observed (all p > 0.10). In multivariate analysis, myopia was associated with decreasing age (odds ratio [OR] = 0.86, p = 0.01; per year increase), higher blood levels of haemoglobin A1c (HbA1c ) (OR = 1.12, p = 0.05; per unit increase), higher education levels (OR = 5.10, p < 0.001; university or college versus illiterate or primary school) and the presence of nuclear cataract (OR = 2.36, p < 0.001). CONCLUSIONS: Refractive errors may be associated with glycaemic control among T2DM patients. Longitudinal analyses are warranted to examine the relationship between changes in HbA1c and the development of refractive errors.

Iris colour in relation to myopia among Chinese school-aged children.

PURPOSE: Understanding the association of iris colour and myopia may provide further insights into the role of the wavelength of lights in the pathophysiology of myopia. We aim to assess the association of iris colour and myopia in a school-based sample of Chinese students. METHODS: Two thousand three hundred and forty-six Year 7 students from 10 middle schools (93.5% response rate) aged 13-14 years in Mojiang, a small county located in Southwestern China, participated in the study. We obtained standardised slit lamp photographs and developed a grading system assessing iris colour (higher grade denoting a darker iris). Refractive error was measured after cycloplegia using an autorefractor by optometrists or trained technicians. An IOLMaster (www.zeiss.com) was used to measure ocular biometric parameters including axial length (AL). RESULTS: Of all the study participants, 693 (29.5%) were affected by myopia with the prevalence estimates being higher in girls (36.8%; 95% confidence interval [CI]: 34.0, 39.6) than in boys (22.8%; 95% CI: 20.4, 25.1) (p < 0.001). After adjusting for gender, height, parental history of myopia, time spent on computer, time spent watching TV, time spent outdoors, and time spent reading and writing, participants with a darker iris colour tended to have a higher prevalence of myopia, a more myopic refraction and a longer AL. Dose-response relationships were observed in all regression models (p for trend <0.05). CONCLUSIONS: Darker iris colour was associated with more myopic refractive errors and longer ALs among Chinese school-aged children and this association was independent of other known myopia-related risk factors.

Epidemiology of Reduced Visual Acuity among Chinese Multiethnic Students.

SIGNIFICANCE: Data regarding the epidemiology of reduced visual acuity (VA) among multiethnic children and adolescents in China are few. Understanding the vision-related health inequalities among different ethnic groups is crucial for health resource allocations and clinical managements for eye diseases. PURPOSE: We aim to determine the prevalence, main causes, and health inequalities of reduced VA in multiethnic school students in rural China. METHODS: A school-based eye survey including 7681 multiethnic school students aged 5 to 16 years in the southwestern part of China was conducted. Detailed ocular examinations including VA measurements, ocular motility evaluations, bilateral postcycloplegic refractions, and the assessments of the external eye, anterior segment, media, and retinal fundus were carried out by trained research vision professionals. Visual acuity was measured using a logarithm of the minimum angle of resolution E-chart, and reduced VA was defined as a presenting VA of worse than 20/40. Concentration index was initiatively utilized to measure health inequalities among different ethnic groups. RESULTS: The prevalence of reduced VA was 11.4 per 100 children (95% confidence interval, 10.7 to 12.1%) based on the worse-seeing eye data. The prevalence of reduced VA increased with increasing age (P < .001 for trend) and was higher among girls compared with boys (P < .0001). Uncorrected refractive error was the principal cause for reduced VA, which accounted for 87.3% of the participants with reduced VA. The concentration index for reduced VA was 0.07 among different ethnic groups. CONCLUSIONS: Compared with the estimates reported from previous studies on Chinese children and adolescents, a relatively lower prevalence of reduced VA was observed among multiethnic school students in rural China. Ethnic variations and health inequalities of reduced VA were not significant in this study.

Prevalence, Awareness, and Risk Factors of Diabetic Retinopathy among Adults with Known Type 2 Diabetes Mellitus in an Urban Community in China.

PURPOSE: To understand the prevalence, awareness, and risk factors for diabetic retinopathy (DR) among Chinese with known type-2 diabetes mellitus (T2DM) in eastern China communities. METHODS: A community-based survey including 913 patients with known T2DM was conducted in Suzhou, China. Diabetes was defined as hemoglobin A1c (hbA1c) ≥6.5%, use of diabetic medication or a physician diagnosis of diabetes. Retinal photographs were graded for the presence of DR using the Airlie House classification system. Binary logistic regression models were established to examine the associations of risk factors with DR and vision-threatening diabetic retinopathy (VTDR). RESULTS: The overall prevalence of any DR was 18.0% (95% confidence interval [CI]: 15.5-20.6%) in this population. VTDR affected 4.4% (95% CI: 3.1-5.8%) of the study participants. In multivariate analysis, the presence of DR among T2DM patients was associated with decreased age (odds ratio [OR] = 0.97; p = 0.01; per year increase), longer durations of diabetes (OR = 1.02; per year increase; p = 0.03), higher blood levels of hbA1c (OR = 1.15; per unit increase; p = 0.03). Of the 158 participants with DR, only 12 (8%) had been aware of their condition or had been diagnosed previously as having DR. CONCLUSIONS: The prevalence of DR among diabetes patients in eastern China was lower than those in northern China. The awareness of DR was poor, which emphasizes the pressing need for increasing the public awareness of this vision-threatening eye disorder and routine eye screening should be performed among T2DM patients in the communities.

Time outdoors, blood vitamin D status and myopia: a review.

BACKGROUND: Myopia is a major public health concern throughout the world and the prevalence has been increasing rapidly in recent years, especially in urban Asia. The "vitamin D hypothesis" has been raised recently because vitamin D may be a link between less time outdoors and increased risk of myopia. METHODS: We reviewed all studies published in English which examined the association of time outdoors and blood vitamin D status with myopia. RESULTS: The protective effect of time spent outdoors on the risk of myopia onset has been well-established with numerous observational studies and three trials published. Five studies reporting the association between the blood vitamin D status and the risk of myopia and two studies examining the variations in the vitamin D receptor as potential risk factors for myopia development were identified. Most of the current evidence was cross-sectional in nature and had not properly controlled important confounders in its analyses. The evidence supporting that vitamin D played a role in myopia development is weak and the mechanisms are unclear. CONCLUSIONS: At the current stage, it is still unclear whether blood vitamin D status regulates the onset or progression of myopia. Blood vitamin D status may only serve as a biomarker of outdoor exposure, which is the real protective factor for myopia.

Apgar score and reduced vision in children aged 3 to 6 years.

PURPOSE: We aimed to examine the association between the 5-min Apgar score and reduced vision in children 3 to 6 years of age. METHODS: A total of 5834 preschool children aged 3 to 6 years participated in this school-based eye survey. Reduced vision was defined as unaided distance vision of 6/12 or worse in the better-seeing eye. The 5-min Apgar scores of the participants were retrieved from medical records. RESULTS: The overall prevalence of reduced vision in this population was 6.63 % (95 % confidence interval [CI] 5.99-7.27). In multivariate analysis, the presence of reduced vision was associated with a low 5-min Apgar score at birth (<7 vs. 7-10; odds ratio [OR] = 1.66, 95 % CI 1.48-3.05) after adjusting for age, gender, parental history of myopia, maternal age, gestational age, and birth weight. In addition, both myopia and amblyopia were associated with Apgar scores of less than 7 in multivariate analyses. CONCLUSIONS: Children with 5-min Apgar scores of less than 7 were more likely to have reduced vision at the age of 3 to 6 years.

Visual Impairment among Older Adults in a Rural Community in Eastern China.

Purpose. To determine the prevalence, causes, and associations of visual impairment (VI) among participants aged 60 years or older in a rural community in China. Methods. A community-based survey was undertaken in a rural town located in Eastern China and 4579 people aged 60 years or older participated in the study. Presenting visual acuity was assessed using a Snellen chart with tumbling-E optotypes and anterior segment was examined using a slit-lamp. VI was defined as presenting VA <6/18 and it included moderate VI (<6/18 to 6/60) and blindness (<6/60). Results. The prevalence of VI was 5.4% (95% confidence interval [CI] 4.7-6.0). In multivariate analysis, the presence of VI was positively associated with increasing age (odds ratio [OR] = 1.12, 95% CI 1.10-1.16, per year increase), female gender (OR = 2.33, 95% CI 1.53-3.55), the presence of hypertension (OR = 1.31, 95% CI 1.001-1.85), living alone (OR = 1.52, 95% CI 1.08-2.62), and increased sleeping hours (OR = 1.10, 95% CI 1.001-1.22). Drinking 3 or more glasses of green tea per day was inversely associated with VI (OR = 0.79, 95% CI 0.63-0.98). Conclusion. VI was less prevalent in this community compared with previous report in other areas in China.

Population-based assessment of visual impairment among ethnic Dai adults in a rural community in China.

Dai ethnicity is one of the major Chinese ethnic minorities with a population of about 1.2 million. We aimed to determine the prevalence and potential causes of visual impairment (VI) among ethnic Dai adults aged 50 years or older in a rural community in China. A population-based survey including 2163 ethnic Dai people (80.5%) was undertaken using a random cluster sampling strategy. The detailed eye examination was performed after pupil dilation by trained study ophthalmologists and optometrists. Presenting visual acuity (PVA) and best-corrected visual acuity (BCVA) was measured using the Early Treatment Diabetic Retinopathy Study logMAR chart and VI was defined as a VA of less than 20/63 in the better-seeing eye. The overall prevalence of presenting blindness and low vision was 3.0% (95% CI, 2.3-3.7) and 13.3% (95% CI, 11.9-14.8), respectively. The prevalence estimates were reduced to 2.1% (95% CI, 1.5-2.8) and 6.7% (95% CI, 5.7-7.8) when BCVA was considered. Men were more likely to be affected by low vision but less likely to be blind compared with women. Cataract accounted for 62.7% of presenting low vision and 68.8% of presenting blindness, respectively. In conclusion, VI was a significant health concern in Dai Chinese in China.

Myopia among school students in rural China (Yunnan).

PURPOSE: We described the prevalence and associated factors of myopia and high myopia in school children of different ethnicities in a rural community in Yunnan province, China. METHODS: A total of 7681 (93.4%) primary and secondary school students aged 5-16 years in Mangshi participated in this study. Cycloplegic refraction was performed using an auto-refractor. Information regarding demographic factors, socioeconomic status and lifestyle-related exposures were collected using a questionnaire. Multivariate logistic regression models were fitted to estimate the risk factors for myopia and high myopia. RESULTS: The overall prevalence of myopia and high myopia was 39.1% (95% confidence interval [CI]: 38.0, 40.2) and 0.6% (95% CI: 0.4, 0.8) in this study. Myopia prevalence increased significantly with increasing age (p for trend <0.001). Girls were more likely to have myopia compared with boys (p < 0.001). In multivariate analysis, the presence of myopia was associated with increasing height (odds ratio [OR] = 1.02; 95% CI: 1.01, 1.03), computer use (OR = 1.17; 95% CI: 1.03, 1.32), having myopic father (OR = 1.56; 95% CI: 1.24, 1.94), having myopic mother (OR = 1.33; 95% CI: 1.08, 1.63), and increasing time on reading (OR = 1.18; 95% CI: 1.09, 1.28) after adjusting for age, sex and ethnicity. CONCLUSIONS: Nowadays myopia but not high myopia is prevalent among school children in rural China. Significant ethnic differences in myopia prevalence were not observed. A significant 'cohort effect' of myopia previously observed in urban cities had occurred in rural communities in China.