Prenatal and neonatal factors for the development of childhood visual impairment in primary and middle school students: a cross-sectional survey in Guangzhou, China

Abstract

ObjectivesIn this cross-sectional survey, we sought to determine the prevalence of and the influence of prenatal and neonatal factors on childhood visual impairment without correction (VIUC) in a paediatric population from Guangzhou, China.SettingThe health survey covered 11 administrative districts in Guangzhou, including 991 schools.ParticipantsAll of the primary and middle school students in Guangzhou were invited to complete an online questionnaire with the help of their parents. The results of physical examinations were reported by school medical departments. The results of the questionnaire were collected by the researchers. In total, 253 301 questionnaires were collected.Primary outcome measuresThe students’ uncorrected visual acuity (UCVA) was examined by trained optometrists by standard logarithmic visual acuity charts. VIUC was defined by UCVA (of the better eye) (UCVA <6/12) with three levels: light VIUC (UCVA ≥6/18 to <6/12), mild VIUC (UCVA ≥6/60 to <6/18) and severe VIUC (UCVA <6/60).ResultsA total of 39 768 individuals (15.7%) had VIUC, and the rate was much higher among grade 10 to 12 students (51.4%) than among grade 1 to 6 students (6.71%). The following factors were significantly associated with an increased risk of VIUC: female gender, high birth weight, formula feeding, not having siblings, higher level of parents’ education, parental myopia, much homework time and little outdoor activity. Delivery mode was not associated with the risk of VIUC.ConclusionsThis study validates known major prenatal/genetic, perinatal and postnatal factors for childhood VIUC. In conclusion, prenatal and perinatal factors can affect the onset of childhood VIUC, but parental myopia and postnatal factors are the main factors.

The Association Between Refractive Errors and Breastfeeding in Pakistani Children: A Case-Control Study

“…Although most studies show a positive relationship between outdoor time and vision, our data revealed no such association [9,12,13].…”

“…Similar to our results, a very extensive study by Chong et al [17] revealed a reduced risk of myopia development in breastfed children (43% lower than nonbreastfed). Liu et al [24] had similar findings and demonstrated that children breastfed for a duration of more than six months had a 49.8% lower chance of developing myopia and that parental myopia was strongly associated with the child developing myopia, which was also highlighted in our results [12,13,24,25].…”

“…Parental myopia is perhaps the most research-backed and clinically recognized risk factor for a child developing myopia, followed by outdoor activity as a protective element in environmental factors [4,5,11,12,13]. Studies have also been carried out to investigate the effects of breastfeeding on visual development in the early years of life; these have revealed that breast milk contains omega-3 and essential fatty acids that play a vital role in cognitive and visual development [14], reducing various ocular morbidities, and preventing retinopathy of prematurity [15].…”

School-related sedentary behaviours and indicators of health and well-being among children and youth: a systematic review

“…Study designs included cross-over trial, non-randomized interventions, and longitudinal with up to 4 years follow-up, and cross-sectional. Risks (injury)/harms were assessed objectively through eye examinations for myopia, visual acuity, and visual impairment; and subjectively pain/discomfort (abdominal, ankles/feet, back, elbow, hip/thigh, knee, lower back, lower limbs, neck and shoulder, neck, shoulder, upper back, upper limbs, wrist/hands, and overall pain or discomfort using the Nordic Musculoskeletal Questionnaire, HBSC survey, or study-specific questionnaires), headaches (study-specific questionnaires), well-being (self-report HBSC), and global health (parent-report questionnaire) a Intervention first condition, and control group first condition were in the same classroom b Only one study, with a small sample size c Unfavourable for odds of elbow, low back, neck, and shoulder pain, as well as for less neck pain, but null for all other areas of pain [ 98 ] d 2/3 studies had intervention and control groups in the same school e Study did not demonstrate psychometric testing of subjectively measured exposure variables f Only one study, but did have large sample size g 9/15 studies did not demonstrate psychometric testing of subjectively measured exposure variables h 5: null and unfavourable [1: unfavourable for too much homework and shoulder pain, but null for not enough and shoulder pain, and all neck pain [ 105 ]; 1: unfavourable for too much, null for not enough [ 106 ]; 1: unfavourable for > = 60 min and myopia, null for all visual acuity and myopia 1–30 and 31–60 min homework [ 107 ]; 1: unfavourable overall and > = 2 h of homework, null for 0.5–1.9 h/day [ 99 ]; 1: unfavourable for boys weekday homework and odds of pain, but null for all other outcomes and sub-groups (11/12 associations) [ 108 ]; 2 : favourable and null and unfavourable findings [1: dose response-generally favourable associations at 1–2 h of studying, unfavourable at > 3 h and 2–3 h [ 109 ]; 1: dose response-favourable associations at 6–8 and 8–10 h, but null for > 10 h and 4–6 h (compared to < 4 h), and unfavourable for extra learning tasks after class [ 110 ]]…”

“…h 5: null and unfavourable [1: unfavourable for too much homework and shoulder pain, but null for not enough and shoulder pain, and all neck pain [ 105 ]; 1: unfavourable for too much, null for not enough [ 106 ]; 1: unfavourable for > = 60 min and myopia, null for all visual acuity and myopia 1–30 and 31–60 min homework [ 107 ]; 1: unfavourable overall and > = 2 h of homework, null for 0.5–1.9 h/day [ 99 ]; 1: unfavourable for boys weekday homework and odds of pain, but null for all other outcomes and sub-groups (11/12 associations) [ 108 ]; 2 : favourable and null and unfavourable findings [1: dose response-generally favourable associations at 1–2 h of studying, unfavourable at > 3 h and 2–3 h [ 109 ]; 1: dose response-favourable associations at 6–8 and 8–10 h, but null for > 10 h and 4–6 h (compared to < 4 h), and unfavourable for extra learning tasks after class [ 110 ]]…”