Donghyun Jee

Prevalence of myopia and its association with body stature and educational level in 19-year-old male conscripts in seoul, South Korea.

PURPOSE To examine prevalence of refractive errors and its associated factors, such as body stature and educational level, among 19-year-old males in Seoul, Korea. METHODS A population-based cross-sectional study was performed in male subjects (n = 23,616; age = 19 years) who were normally resident in Seoul for male compulsory conscripts during the study period (2010). Refractive examination was performed with cycloplegia. Height, weight, and educational level were examined. Myopia was defined as a spherical equivalent less than -0.5 diopters (D) and high myopia less than -6.0 D. The association of myopia with body stature and educational level was analyzed using logistic regression analysis. RESULTS The prevalence of myopia in 19-year-old males in Seoul was 96.5%. The prevalence of high myopia was 21.61%. Body stature was not significantly associated with myopia. Four- to 6-year university students (odds ratio [OR] 1.69; P < 0.001) and 2 to 3-year college students (OR 1.68; P < 0.001) showed significantly higher risk for myopia than those with lower academic achievement (< high school graduation). CONCLUSIONS The 19-year-old male population in Seoul, Korea, demonstrated a very high myopic prevalence. Myopic refractive error was associated with academic achievement, not with body stature.

Prevalence and risk factors for refractive errors: Korean National Health and Nutrition Examination Survey 2008-2011.

Purpose To examine the prevalence and risk factors of refractive errors in a representative Korean population aged 20 years old or older. Methods A total of 23,392 people aged 20+ years were selected for the Korean National Health and Nutrition Survey 2008–2011, using stratified, multistage, clustered sampling. Refractive error was measured by autorefraction without cycloplegia, and interviews were performed regarding associated risk factors including gender, age, height, education level, parents education level, economic status, light exposure time, and current smoking history. Results Of 23,392 participants, refractive errors were examined in 22,562 persons, including 21,356 subjects with phakic eyes. The overall prevalences of myopia (< -0.5 D), high myopia (< -6.0 D), and hyperopia (> 0.5 D) were 48.1% (95% confidence interval [CI], 47.4–48.8), 4.0% (CI, 3.7–4.3), and 24.2% (CI, 23.6–24.8), respectively. The prevalence of myopia sharply decreased from 78.9% (CI, 77.4–80.4) in 20–29 year olds to 16.1% (CI, 14.9–17.3) in 60–69 year olds. In multivariable logistic regression analyses restricted to subjects aged 40+ years, myopia was associated with younger age (odds ratio [OR], 0.94; 95% Confidence Interval [CI], 0.93-0.94, p < 0.001), education level of university or higher (OR, 2.31; CI, 1.97–2.71, p < 0.001), and shorter sunlight exposure time (OR, 0.84; CI, 0.76–0.93, p = 0.002). Conclusions This study provides the first representative population-based data on refractive error for Korean adults. The prevalence of myopia in Korean adults in 40+ years (34.7%) was comparable to that in other Asian countries. These results show that the younger generations in Korea are much more myopic than previous generations, and that important factors associated with this increase are increased education levels and reduced sunlight exposures.

Prevalence and risk factors for myopia in a rural Korean population.

PURPOSE To assess the prevalence and risk factors of myopia in 19-year-old males in Jeju, a rural area of Korea. METHODS A total of 2805 subjects were included. Refractive examination was performed with cycloplegia to test for myopia (< -0.5 diopters [D]) and high myopia (< -6.0 D). Possible associated factors were evaluated including height, weight, educational level, and color vision deficiency. RESULTS The prevalence of myopia and high myopia were 83.3% and 6.8%, respectively, in 19-year-old males in Jeju. University students in their fourth to sixth years showed a higher risk for myopia (odds ratio [OR] 2.04; 95% confidence interval [CI], 1.52-2.71, P < 0.001) than those with lower academic achievement. CONCLUSIONS The prevalence of myopia was relatively high (83.3%) in a rural area of Korea, while the rate of high myopia was relatively low (6.8%) compared with that (20.6%) in an urban area of Korea.

Prevalence and risk factors for diabetic retinopathy: the Korea National Health and Nutrition Examination Survey 2008-2011.

PURPOSE We evaluated the prevalence and risk factors for diabetic retinopathy (DR) in a representative Korean population. METHODS This cross-sectional study involved 16,109 subjects aged >40 years who had participated in the Korean National Health and Nutrition Survey from 2008 to 2011. Seven standard retinal fundus photographs were obtained after pupil dilatation from both eyes. The DR was graded using the modified Airlie House classification system. Risk factors for DR and vision-threatening diabetic retinopathy (VTDR) were evaluated, including age, sex, diabetes duration, glycated hemoglobin (HbA1c), hypertension, lipid profiles, and refractive error. RESULTS Of the 16,109 eligible individuals participating in the study, 14,595 (90.6%) had fasting blood glucose results available. Of these, 2023 (13.8%) were diagnosed with diabetes mellitus. Among these, gradable photographs were available for 1678 subjects (82.9%), including 1323 subjects with known diabetes mellitus (KDM) and 355 with newly diagnosed diabetes mellitus (NDM). The prevalences of any DR and VTDR were 15.8% (95% confidence interval [CI], 14.1-17.5), and 4.6% (95% CI, 3.6-5.6), respectively. Any DR was associated with a longer duration of diabetes (odds ratio [OR], 1.08; 95% CI, 1.06-1.10), higher HbA1C level (OR, 1.52; 95% CI, 1.28-1.80), higher systolic blood pressure (OR, 1.02; 95% CI, 1.01-1.03), and lower body mass index (OR, 0.91; 95% CI, 0.87-0.96) in a multivariate analysis. CONCLUSIONS We provide data on the prevalence and risk factors for DR in a representative Korean population. The prevalence of any DR and VTDR in the Korean population was lower than that reported previously. The condition of DR was associated with a longer duration of diabetes, poor glycemic control, and higher systemic blood pressure.

Inverse Relationship Between High Blood 25-Hydroxyvitamin D and Late Stage of Age-Related Macular Degeneration in a Representative Korean Population

PURPOSE To investigate the association of 25-hydroxyvitamin D with AMD. METHODS A population-based, cross-sectional study using a nationwide, systemic-stratified, multistage-clustered sampling method involved a total of 17,045 subjects older than 40 years who participated in the Korean National Health and Nutrition Examination Survey 2008 to 2012. All participants underwent standardized interviews, evaluation of blood 25-hydroxyvitamin D levels, and comprehensive ophthalmic examinations. A 45° digital fundus photograph of both eyes was taken under physiologic mydriasis. All fundus photographs were graded using the international classification and grading system. RESULTS Blood 25-hydroxyvitamin D levels were 17.5 ng/mL in women and 20.0 ng/mL in men. After adjusting for potential confounders including age, sex, smoking status, hypertension, heart problems, stroke, and sunlight-exposure time, the odds ratio (OR) for late AMD significantly decreased in the highest blood 25-hydroxyvitamin D quintile (OR, 0.32; 95% confidence interval [CI], 0.12-0.81; P for trend = 0.018) compared with the lowest quintile in men, but not in women. Early AMD was not associated with blood 25-hydroxyvitamin D levels in either sex. CONCLUSIONS High level of blood 25-hydroxyvitamin D was inversely associated with late AMD in men but not women. Considering antiangiogenic and antifibrotic action of vitamin D, association between two variables warrants further studies.

Comparison of treatment with preservative-free versus preserved sodium hyaluronate 0.1% and fluorometholone 0.1% eyedrops after cataract surgery in patients with preexisting dry-eye syndrome

Purpose To compare treatment with preservative‐free and preserved sodium hyaluronate 0.1% and fluorometholone 0.1% eyedrops after cataract surgery in patients with preexisting dry‐eye syndrome. Setting Bucheon St. Mary’s Hospital, Catholic University of Korea, Seoul, Korea. Design Randomized controlled study. Methods Patients with cataract and dry‐eye syndrome were randomly divided into 2 groups. Group 1 patients were treated with preservative‐free sodium hyaluronate 0.1% and preservative‐free fluorometholone 0.1% eyedrops 4 times a day in the first month and twice a day in the second month. Group 2 patients were treated with preserved eyedrops using the same schedule. Ocular Surface Disease Index (OSDI) score, tear‐film breakup time (TBUT), Schirmer I test, corneal fluorescein staining, impression cytology, and antioxidant and inflammatory cytokine activities in tears were evaluated. Results Both groups comprised 40 patients. At 2 months, the OSDI score, TBUT, Schirmer I score, fluorescein staining score, impression cytology findings, and goblet cell count were significantly better in Group 1 than in Group 2 (P<.05). The interleukin‐1&bgr; and tumor necrosis factor‐&agr; concentrations were significantly less in the tears of Group 1 patients than in the tears of Group 2 patients, and catalase and superoxide dismutase 2 fluorescence intensities were significantly greater in the tears of Group 1 patients than in the tears of Group 2 patients (P<.05). Conclusions Preservative‐free sodium hyaluronate 0.1% and fluorometholone 0.1% eyedrops can improve the symptoms and signs of dry‐eye syndrome after cataract surgery. Preservative‐free fluorometholone eyedrops may have antiinflammatory and antioxidant effects in tears of patients with dry‐eye syndrome. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Inverse Association between High Blood 25-Hydroxyvitamin D Levels and Diabetic Retinopathy in a Representative Korean Population

Purpose To investigate the association between 25-hydroxyvitamin D and diabetic retinopathy (DR). Methods A population-based cross-sectional study using a nation-wide, systemically stratified, multistage, clustered sampling method included a total of 18,363 subjects aged ≥40 years who participated in the Korean National Health and Nutrition Examination Survey during 2008–2012. All participants participated in standardized interviews, blood 25-hydroxyvitamin D level evaluations, and comprehensive ophthalmic examinations. Seven standard retinal fundus photographs were obtained from both eyes after pupil dilatation. DR was graded according to the modified Airlie House classification system. Results The blood 25-hydroxyvitamin D levels were 19.2 ng/mL in men and 17.9 ng/mL in women. After adjusting for potential confounders, including age, sex, diabetes duration, hemoglobin A1c levels, and hypertension, the odds ratios (OR) for any DR and proliferative DR among men decreased significantly in the highest blood 25-hydroxyvitamin D level quintile relative to the lowest quintile (OR, 0.37; 95% confidence interval [CI], 0.18–0.76; P for trend  = 0.004 and OR, 0.15; 95% CI, 0.03–0.83; P for trend  = 0.043). Conclusions This study provides the first epidemiologic findings of the inverse relationships of blood 25-hydroxyvitamin D levels with any DR and proliferative DR only in men. Considering anti-angiogenic and anti-fibrotic action of vitamin D, further studies including longitudinal and interventional analysis are warranted.

Prevalence and Risk Factors for Age-Related Macular Degeneration: Korean National Health and Nutrition Examination Survey 2008–2011

Abstract Purpose: To evaluate the prevalence of and risk factors for age-related macular degeneration (AMD) in a representative Korean population. Materials and Methods: A nationwide population-based cross-sectional study was conducted among the civilian, noninstitutionalized Korean population aged 40 and older (mean age, 55.7 years; 95% confidence interval [CI], 55.4–56.0). A total of 16,109 older (≥40 years of age) subjects participated in the Korean National Health and Nutrition Survey 2008–2011. All participants underwent standardized interviews and comprehensive ophthalmic examinations. Using physiologic mydriasis, a 45° digital fundus photograph was taken of both eyes of each participant. All fundus photographs were graded according to an international classification and grading system. Main outcome measures consisted of prevalence of early- and late-AMD. Results: Of the 16,109 subjects, fundus photographs were gradable for 14,352 (89.1%). The prevalence of early- and late-AMD in the Korean population was 6.0 and 0.6%, respectively. The prevalence of early-AMD increased from 1.5% in those aged 40–49 years to 16.2% in those aged ≥70 years. After adjusting for confounders, the prevalence of early-AMD increased with increasing age (odds ratio [OR], 1.08; CI, 1.06–1.09). For late-AMD, old age (OR, 1.09; CI, 1.04–1.14), male gender (OR, 2.45; CI, 1.11–5.37), high systolic blood pressure (OR, 1.03; CI, 1.00–1.06) and high fasting glucose level (OR, 0.97; CI, 0.94–0.99) were significant risk factors. Smoking was not associated with either early- or late-AMD in this Korean population. Conclusions: The present study provides the first population-based data on the prevalence of and risk factors for AMD in a representative Korean population. The prevalences of early- and late-AMD in this population were 6.0 and 0.6%, respectively. The prevalence of AMD in Koreans is higher than for those in other Asian countries and similar to that of Caucasians in Western countries.

Association between blood cadmium level and age-related macular degeneration in a representative Korean population.

PURPOSE To investigate the association between blood cadmium level and AMD. METHODS This population-based, cross-sectional study using a nationwide, systemically stratified, multistage, clustered sampling method included 4933 subjects older than 40 years who participated in the Korean National Health and Nutrition Examination Survey (KNHANES) between 2008 and 2012 and had fundus photographs taken. All participants underwent a standardized interview, evaluation of blood cadmium concentrations, and comprehensive ophthalmic examination. A 45° digital fundus photograph was taken from both eyes under physiologic mydriasis, and were graded using the international classification and grading system for AMD. RESULTS Mean blood cadmium levels were 1.47 μg/L in women and 1.19 μg/L in men. After adjusting for potential confounders, including age, sex, and smoking status, the odds ratio (OR) for AMD was significantly increased in the highest quintile blood cadmium group (OR, 1.96; 95% confidence interval [CI], 1.17-3.29; P for trend = 0.017). This association between blood cadmium level and AMD was significant in men (OR, 2.11; 95% CI, 1.11-4.02; P for trend = 0.024), but not in women (OR, 1.29; 95% CI, 0.70-2.52; P for trend = 0.158). CONCLUSIONS This study provides the first epidemiologic evidence that higher blood cadmium level is associated with AMD. Results of the present study indicate that an elevated cadmium burden may increase the risk of AMD development.

Clinical Course and Risk Factors of Diabetic Retinopathy in Patients with Type 2 Diabetes Mellitus in Korea

Background We investigated clinical course and risk factors for diabetic retinopathy (DR) in patients with type 2 diabetes mellitus (T2DM). Methods A total of 759 patients with T2DM without DR were included from January 2001 to December 2004. Retinopathy evaluation was performed at least annually by ophthalmologists. The severity of the DR was classified into five categories according to the International Clinical Diabetic Retinopathy Severity Scales. Results Of the 759 patients, 523 patients (68.9%) completed the follow-up evaluation. During the follow-up period, 235 patients (44.9%) developed DR, and 32 patients (13.6%) progressed to severe nonproliferative DR (NPDR) or proliferative DR (PDR). The mean duration of diabetes at the first diagnosis of mild NPDR, moderate NPDR, and severe NPDR or PDR were 14.8, 16.7, and 17.3 years, respectively. After adjusting multiple confounding factors, the significant risk factors for the incidence of DR risk in patients with T2DM were old age, longer duration of diabetes, higher mean glycosylated hemoglobin (HbA1c), and albuminuria. Even in the patients who had been diagnosed with diabetes for longer than 10 years at baseline, a decrease in HbA1c led to a significant reduction in the risk of developing DR (hazard ratio, 0.73 per 1% HbA1c decrement; 95% confidence interval, 0.58 to 0.91; P=0.005). Conclusion This prospective cohort study demonstrates that glycemic control, diabetes duration, age, and albuminuria are important risk factors for the development of DR. More aggressive retinal screening for T2DM patients diagnosed with DR should be required in order to not miss rapid progression of DR.