Mohamed Dirani

Outdoor Activity and Myopia in Singapore Teenage Children

Aim: To investigate the relationship of outdoor activities and myopia in Singapore teenage children. Methods: Teenage children (1249 participants), examined in the Singapore Cohort study Of Risk factors for Myopia (SCORM), during 2006 were included in analyses. Participants completed questionnaires that quantified total outdoor activity, and underwent an eye examination. Results: The mean total time spent on outdoor activity was 3.24 h/day. The total outdoor activity (h/day) was significantly associated with myopia, odds ratio 0.90 (95% CI 0.84 to 0.96) (p = 0.004), after adjusting for age, gender, ethnicity, school type, books read per week, height, parental myopia, parental education and intelligence quotient. In addition, the total time spent outdoors was associated with significantly less myopic refraction (regression coefficient = 0.17; CI 0.10 to 0.25, p<0.001) and shorter axial length (regression coefficient −0.06 (CI −0.1 to −0.03, p<0.001). Total sports was also significantly negatively associated with myopia (p = 0.008) but not indoor sports (p = 0.16). Conclusions: Participants who spent more time outdoors were less likely to be myopic. Thus, outdoor activity may protect against development of myopia in children, supporting recent Australian data. As near work did not predict outdoor activity, this can be viewed as an independent factor and not merely the reciprocal of near work.

Prevalence of refractive error in Singaporean Chinese children: the Strabismus, Amblyopia, and Refractive Error in Young Singaporean Children (STARS) Study.

PURPOSE To determine the prevalence of refractive error types in Singaporean Chinese children aged 6 to 72 months. METHODS The Strabismus, Amblyopia and Refractive Error in Singaporean Children (STARS) is a population-based study in southwest Singapore. Door-to-door recruitment of participants was used, with disproportionate random sampling in 6-month increments. Parental questionnaires were administered. Participant eye examinations included logMAR visual acuity, cycloplegic autorefraction, and ocular biometry. Overall and age-specific prevalences of myopia (spherical equivalence [SE] <or= -0.50 D), high myopia (SE <or= -6.00 D), hyperopia (SE >or= +3.00 D), astigmatism (cylinder >or= +1.50 D), and anisometropia (SE difference between each eye >or=2.00 D) were calculated. RESULTS A total of 3009 children were examined (participation rate, 72.3%). Right eye (OD) cycloplegia data were available for 1375 boys and 1264 girls (mean age, 41 months). Mean OD SE was +0.69 D (SD 1.15). Overall myopia prevalence was 11.0% with no variance between the sexes (P = 0.91). The prevalence of high myopia (at least -6.00 D) was 0.2%. The prevalences of hyperopia, astigmatism, and anisometropia were 1.4%, 8.6%, and 0.6%, respectively. Most astigmatism (>95%) was with-the-rule (cylinder axes between 1 degrees and 15 degrees or 165 degrees and 180 degrees ). Myopia was present in 15.8%, 14.9%, 20.2%, 8.6%, 7.6%, and 6.4% of children aged 6 to 11, 12 to 23, 24 to 35, 36 to 47, 48 to 59, and 60 to 72 months, respectively. Prevalence increased with age for astigmatism (P < 0.001), but not for hyperopia or anisometropia (P = 0.55 and P = 0.37), respectively. CONCLUSIONS The prevalences of myopia and astigmatism in young Singaporean Chinese children are high, but that of hyperopia is low. Age effects were observed for each refractive error category, but differences between the sexes were not significant. Age-related variation in myopia prevalence may be influenced by ocular development, environment, and/or testability.

Prevalence of Amblyopia and Strabismus in Young Singaporean Chinese Children

PURPOSE. To determine the prevalence of amblyopia and strabismus in young Singaporean Chinese children. METHODS. Enrolled in the study were 3009 Singaporean children, aged 6 to 72 months. All underwent complete eye examinations and cycloplegic refraction. Visual acuity (VA) was measured with a logMAR chart when possible and the Sheridan-Gardner test when not. Strabismus was defined as any manifest tropia. Unilateral amblyopia was defined as a 2-line difference between eyes with VA < 20/30 in the worse eye and with coexisting anisometropia (> or =1.00 D for hyperopia, > or =3.00 D for myopia, and > or =1.50 D for astigmatism), strabismus, or past or present visual axis obstruction. Bilateral amblyopia was defined as VA in both eyes <20/40 (in children 48-72 months) and <20/50 (<48 months), with coexisting hyperopia > or =4.00 D, myopia < or = -6.00 D, and astigmatism > or =2.50 D, or past or present visual axis obstruction. RESULTS. The amblyopia prevalence in children aged 30 to 72 months was 1.19% (95% confidence interval [CI], 0.73-1.83) with no age (P = 0.37) or sex (P = 0.22) differences. Unilateral amblyopia (0.83%) was twice as frequent as bilateral amblyopia (0.36%). The most frequent causes of amblyopia were refractive error (85%) and strabismus (15%); anisometropic astigmatism >1.50 D (42%) and isometropic astigmatism >2.50 D (29%) were frequent refractive errors. The prevalence of strabismus in children aged 6 to 72 months was 0.80% (95% CI, 0.51-1.19), with no sex (P = 0.52) or age (P = 0.08) effects. The exotropia-esotropia ratio was 7:1, with most exotropia being intermittent (63%). Of children with amblyopia, 15.0% had strabismus, whereas 12.5% of children with strabismus had amblyopia. CONCLUSIONS. The prevalence of amblyopia was similar, whereas the prevalence of strabismus was lower than in other populations.

Family history, near work, outdoor activity, and myopia in Singapore Chinese preschool children

Aims To investigate the risk factors for myopia, including near work and outdoor activity, in Singapore Chinese preschool children. Methods A cross-sectional study, with disproportionate random sampling by 6-month age groups, of 3009 Singapore Chinese children aged 6–72 months was performed. Information on family history, near work and outdoor activity was obtained. Spherical equivalent refraction (SER) was assessed. Results Children with two myopic parents were more likely to be myopic (adjusted OR=1.91; 95% CI 1.38 to 2.63) and to have a more myopic SER (regression coefficient=−0.35; 95% CI −0.47 to −0.22) than children without myopic parents. For each 1 cm taller height, the SER was more myopic by 0.01 dioptres. Neither near work nor outdoor activity was associated with preschool myopia. Conclusions A family history of myopia was the strongest factor associated with preschool myopia. In contrast, neither near work nor outdoor activity was found to be associated with early myopia. These data suggest that genetic factors may play a more substantial role in the development of early-onset myopia than key environmental factors.

Are obesity and anthropometry risk factors for diabetic retinopathy? The diabetes management project.

PURPOSE To investigate the relationship between anthropometric parameters and diabetic retinopathy (DR) in adults with diabetes. METHODS Five hundred participants with diabetes were recruited prospectively from ophthalmology clinics in Melbourne, Australia. Each underwent an eye examination, anthropometric measurements, and standardized interview-administered questionnaires, and fasting blood glucose and serum lipids were analyzed. Two-field fundus photographs were taken and graded for DR. Height; weight; body mass index (BMI); waist, hip, neck, and head circumferences; and skinfold measurements were recorded. RESULTS A total of 492 patients (325 men, 66.1%) aged between 26 and 90 years (median, 65) were included in the analysis: 171 (34.8%), 187 (38.0%), and 134 (27.2%) with no DR, nonproliferative DR (NPDR), and proliferative DR (PDR), respectively. After multiple adjustments, higher BMI (odds ratio [OR], 1.06; 95% confidence interval [CI],1.01-1.11; P = 0.02) was significantly associated with any DR. Obese people were 6.5 times more likely to have PDR than were those with normal weight (OR, 6.52; 95% CI, 1.49-28.6; P = 0.013). Neck circumference (OR, 1.05; 95% CI, 1.00-1.10; P = 0.03) and waist circumference (OR, 1.12; 95% CI, 1.03-1.22; P = 0.01) were significantly associated with any DR. BMI (OR, 1.04; 95% CI, 1.00-1.08; P = 0.04) and neck circumference (OR, 1.04 95% CI, 1.01-1.08; P = 0.04) were also positively associated with increasing severity levels of DR. CONCLUSIONS Persons with diabetes with higher BMI and larger neck circumference are more likely to have DR and more severe stages of DR. These data suggest that obesity is an independent risk factor for DR.

Change in Peripheral Refraction over Time in Singapore Chinese Children

PURPOSE. Relative peripheral hyperopia has been associated with central myopia. This study was conducted to determine whether baseline relative peripheral hyperopia is associated with an increased risk of developing myopia or myopia progression in young Singapore Chinese children. METHODS. One hundred eighty-seven children who participated in the Peripheral Refraction in Preschool Children (PREP) Study at baseline underwent a follow-up examination. Autorefraction was performed at five eccentricities with an infrared autorefractor after cycloplegia: central axis and 15° and 30° eccentricities in the nasal and temporal visual fields. The primary outcomes were development of myopia among children who were nonmyopic at baseline, and myopia progression in those who were myopic at baseline. RESULTS. The mean age of the children at baseline was 7.2 ± 3.0 years, and the mean duration of follow-up was 1.26 years. At baseline, 96 children were myopic (mean central spherical equivalent [SE] -2.75 ± 1.72 D) and 91 were nonmyopic (mean central SE 0.76 ± 0.81 D). Baseline relative peripheral hyperopia was not associated with a greater likelihood of becoming myopic or myopia progression. At follow-up, children who remained nonmyopic (n = 24) retained relative peripheral myopia at all eccentricities, whereas those who became myopic (n = 67) developed relative peripheral hyperopia at the nasal (+0.44 ± 0.72 D) and temporal 30° (+0.13 ± 0.74 D). The mean change in central SE was -1.51 ± 0.63 D/y for children who developed myopia, -0.82 ± 0.76 D/y for children who were myopic at baseline, and -1.05 ± 0.80 D/y for all children. CONCLUSIONS. Baseline peripheral refraction did not predict the subsequent onset of myopia or influence the progression of myopia.

Differential Association of Serum Lipids with Diabetic Retinopathy and Diabetic Macular Edema

PURPOSE To assess the association of serum lipids with diabetic retinopathy (DR), diabetic macular edema (DME), and macular thickness in adults with diabetes. METHODS Diabetic patients aged ≥ 18 years were prospectively recruited from specialized eye clinics in Melbourne, Australia. Fasting total-C (cholesterol), triglyceride, HDL-C, non-HDL-C, and LDL-C were assessed. DR was graded from fundus photographs and classified into mild, moderate, severe nonproliferative, and proliferative DR and separately graded for the presence of DME, including clinically significant macular edema (CSME). Macular thickness was assessed using optical coherence tomography (OCT). RESULTS A total of 500 participants (median age, 65 years) were examined. DR, DME, and CSME were present in 321 (66.2%), 149 (33.0%), and 68 (15.0%) patients, respectively. Serum lipid levels were not related to DR or DME. In multivariate models adjusted for traditional risk factors and lipid medications, persons with higher total-, LDL-, and non-HDL-C were more likely to have CSME (odds ratio of 1.54, 1.49, and 1.63 per 1-SD increase, respectively; all P < 0.05). No association was found for serum lipids with macular thickness, as assessed by OCT. The pattern of these associations remained similar in both type 1 and type 2 diabetes, although it was statistically significant only in type 2 diabetes. CONCLUSIONS Serum lipids are independently associated with the CSME, but not with DR, mild or moderate DME, or macular thickness. These data reflect the different impact of hyperlipidemia in the pathogenesis of DR and DME and may explain the discrepancies in previous studies.

Vision-Specific Distress and Depressive Symptoms in People with Vision Impairment

PURPOSE To determine the unique contribution of vision-specific distress in predicting depressive symptoms in people with vision impairment attending a tertiary eye care clinic. METHODS In this cross-sectional study, interview-administered surveys were conducted with 143 adult patients who had presenting visual acuity <0.3 logMAR. Depressive symptoms were assessed with the Patient Health Questionnaire-9 and vision-specific distress was assessed with the Impact of Vision Impairment (IVI) Questionnaire emotional well-being subscale. In addition, level of restriction of participation in common daily activities due to vision impairment was assessed with the IVI and measures of general physical health and social support were included. RESULTS Twenty-one (14.7%) of 143 participants reported clinically significant depressive symptoms and an additional 27.3% (n = 39) had mild depressive symptoms. Vision-specific distress was the strongest unique predictor of depressive symptoms (beta = 0.37, P < 0.001), with physical health (beta = -0.22, P < 0.01), age (beta = -0.18, P < 0.05), and experience of a negative life event (beta = 0.15, P < 0.05) also contributing significantly to depressive symptoms. Results also indicated that vision-specific distress mediates the impact of participation restriction due to vision impairment on depressive symptoms. CONCLUSIONS An assessment of vision-specific distress may be a useful tool with which to identify those at risk of depression or in need of early intervention in eye care or rehabilitation settings. Depression treatment approaches or depression prevention strategies for people with vision impairment may benefit from a focus on vision-specific distress.

Social and emotional impact of diabetic retinopathy: a review

People with vision‐threatening diabetic retinopathy are likely to experience enhanced social and emotional strain. Critically, those with both vision‐threatening diabetic retinopathy and psychosocial problems may have significantly reduced levels of functioning compared with psychologically healthy counterparts. This can cause inadequate compliance, increased strain on family functioning, worse diabetes control, increased progression of diabetic retinopathy and, consequently, further psychosocial stress resulting in a number of concerning implications for disease management, clinical outcomes and healthcare costs. However, the emotional and social health consequences of diabetic retinopathy have not yet been systematically explored. This information is crucial as it allows for a targeted approach to treatment and prevention and avoidance of the potentially detrimental implications described above. Therefore, this paper reviews the current qualitative and quantitative evidence regarding the social and emotional impact of diabetic retinopathy and identifies directions for future research. Key search terms were applied to the electronic databases Pubmed, ISI Web of Science and Embase and the bibliographies of relevant papers were systematically reviewed for additional references. Overall, the evidence suggests that diabetic retinopathy and associated vision loss have several debilitating effects, including disruption of family functioning, relationships and roles; increased social isolation and dependence; and deterioration of work prospects resulting in increased financial strain. Adverse emotional responses include fear, anxiety, vulnerability, guilt, loss of confidence, anger, stress and self‐perception issues. However, the research to date is largely qualitative in nature, with most quantitative studies being small, cross‐sectional and somewhat outdated. Similarly, the outcome measures used in many studies to date are suboptimal in terms of content and validity. Therefore, this review identifies the need for improved outcome measures to provide valid, meaningful measurement of the social and emotional impact of diabetic retinopathy and discusses potential directions for future research such as item banking and computer adaptive testing.

The age-specific prevalence of myopia in Asia: a meta-analysis.

Purpose To estimate the age-specific prevalence of myopia in Asia. Methods We searched PubMed, Embase, and Web of Science from their inception through September 2013 for population-based surveys reporting the prevalence of myopia in adults or children in Asia. We pooled the prevalence estimates for myopia by age groups and by year of birth using a random-effects model. Results We identified 50 eligible population-based studies including 215,672 subjects aged 0 to 96 years reporting the prevalence of myopia from 16 Asian countries or regions. Myopia was found to be most prevalent (96.5%; 95% confidence interval, 96.3 to 96.8) in Koreans aged 19 years. There was no significant linear age group effect on the prevalence of myopia in the whole Asian population but there was a U-shaped relationship between both age and year of birth and the prevalence of myopia. The prevalence of myopia was also higher in those older than 70 years (36.3%; 95% confidence interval, 27.6 to 45.0) compared with other age groups, which revealed nuclear cataract-myopia shifts in refraction. Conclusions There is a large variation in the age-specific prevalence of myopia in Asia. A U-shaped relationship between age and the prevalence of myopia was found in the whole Asian population. The analysis is essential to guide future eye health care, intervention, and clinical management in Asia.