Association between nutrition labelling awareness and the metabolic syndrome: results from the Korean National Health and Nutrition Examination Survey (KNHANES) 2016-2018.

Healthy dietary habits reduce the likelihood for the metabolic syndrome (MS). The present study investigated whether awareness of nutrition information is associated with a decreased likelihood for the MS after adjusting for potential confounders among Korean adults aged 20 years and older. Data were obtained from the Korean National Health and Nutrition Examination Survey 2016-2018. Of the 14 490 participants, 4001 (27·6 %) participants had the MS. In total, 3815 (26·3 %) participants checked nutritional facts and made labelling-dependent purchasing decisions (aware + consider), 7001 (48·3 %) checked nutritional facts but did not make labelling-dependent purchasing decisions or were aware of nutrition facts but did not check them when making food purchasing decisions (aware + not consider) and 3674 (25·4 %) were unaware of nutritional facts (not aware). The aware + consider group was less likely to develop the MS than other groups. The aware + not consider, and not aware groups were at higher association with the MS compared with the aware + consider group. Statistically significant associations were observed between the MS and several demographic characteristics including sex, age, household income, education level, employment status, public health insurance status, smoking status, alcohol consumption and aerobic exercise.

Evaluation of the South Korean national long-term care insurance-funded cognitive function training programme for older people with mild dementia.

OBJECTIVES: despite the extensive literature on the effectiveness of cognitive training, its effectiveness has not been demonstrated within a population-based long-term care system. To provide cognitive training services to older people with mild dementia, Korea introduced a special dementia rating, as a long-term care grades, in the national long-term care insurance in July 2014. These services are only offered to those with the special dementia rating. This study evaluated the national long-term care insurance-funded cognitive function training programme for older people with mild dementia. METHODS: data were derived from the Korean National Health Insurance Elderly Cohort database between 2008 and 2015. We compared changes in function between the intervention (n = 352) and control (n = 1952) groups before (2014) and after (2015) introduction of the cognitive function training programme. Difference-in-differences analysis was performed, to compare changes in each score between the intervention and control groups before and after introduction of the cognitive function training programme. RESULTS: introduction of the cognitive function training programme was associated with significantly less cognitive function decline in the intervention group than in the control groups (ß = -3.39; standard errors [SE] = 1.14; P = 0.003). A subgroup analysis revealed that this effect increased in subjects in the youngest group, low income bracket, who had a primary caregiver, who were supported in multiple activities of daily living by the primary caregiver, or who were not living alone. CONCLUSIONS: introduction of the cognitive function training programme was associated with positive effects on cognitive function.

Undergraduate medical students' perceptions and intentions regarding patient safety during clinical clerkship.

BACKGROUND: The purpose of this study was to examine undergraduate medical students' perceptions and intentions regarding patient safety during clinical clerkships. METHODS: Cross-sectional study administered in face-to-face interviews using modified the Medical Student Safety Attitudes and Professionalism Survey (MSSAPS) from three colleges of medicine in Korea. We assessed medical students' perceptions of the cultures ('safety', 'teamwork', and 'error disclosure'), 'behavioural intentions' concerning patient safety issues and 'overall patient safety'. Confirmatory factor analysis and Spearman's correlation analyses was performed. In total, 194(91.9%) of the 211 third-year undergraduate students participated. RESULTS: 78% of medical students reported that the quality of care received by patients was impacted by teamwork during clinical rotations. Regarding error disclosure, positive scores ranged from 10% to 74%. Except for one question asking whether the disclosure of medical errors was an important component of patient safety (74%), the percentages of positive scores for all the other questions were below 20%. 41.2% of medical students have intention to disclose it when they saw a medical error committed by another team member. CONCLUSIONS: Many students had difficulty speaking up about medical errors. Error disclosure guidelines and educational efforts aimed at developing sophisticated communication skills are needed. This study may serve as a reference for other institutions planning patient safety education in their curricula. Assessing student perceptions of safety culture can provide clerkship directors and clinical service chiefs with information that enhances the educational environment and promotes patient safety.

Exposure amount and timing of solar irradiation during pregnancy and the risk of sensitization in children.

BACKGROUND: Solar irradiation affects sensitization to aeroallergens and the prevalence of allergic diseases. Little is known, however, about how the time and amount of solar irradiation during pregnancy affects such risks in children. We aimed to find out how solar irradiation during pregnancy affects sensitization to aero-allergens and the prevalence of allergic diseases in children. METHODS: This population-based cross-sectional study involved 7301 aged 6 years and aged 12 years children. Maternal exposure to solar irradiation during pregnancy was evaluated using data from weather stations closest to each child's birthplace. Monthly average solar irradiation during the second and third trimesters was calculated with rank by quartiles. Risks of allergic sensitization and allergic disease were estimated. RESULTS: Relative to the first (lowest) quartile, the adjusted odds ratio (aOR) for allergic sensitization in the fourth (highest) quartile was lowest within solar irradiation during pregnancy months 5-6 (aOR = 0.823, 95% CI 0.720-0.942, p < 0.05). During months 9-10, the aOR for allergic sensitization for the fourth was higher than the first quartile of solar irradiation (aOR = 1.167, 95% CI 1.022-1.333, p < 0.05). Similar results were observed when solar irradiation was analyzed as a continuous variable during months 5 (aOR = 0.975, 95% CI 0.962-0.989, p < 0.001) and month 9 (aOR = 1.018, 95% CI 1.004-1.031, p = 0.003). Increased solar irradiation during months 7-8 increased the risk of asthma (aOR = 1.309, 95% CI 1.024-1.674, p = 0.032). CONCLUSIONS: Maternal exposure to solar irradiation during the second trimester of pregnancy associated with reduced aeroallergen sensitization, whereas solar irradiation during the third trimester was related to increased sensitization to aeroallergens.

Reference Values and Utility of Serum Total Immunoglobulin E for Predicting Atopy and Allergic Diseases in Korean Schoolchildren.

The present study aimed to investigate the distribution of total serum immunoglobulin E (IgE) levels in Korean schoolchildren and to evaluate its utility in the prediction of atopy and allergic diseases. A nationwide, cross-sectional survey was conducted in first grade students from randomly selected elementary and middle schools. Total IgE levels were measured by ImmunoCAP. Skin prick tests were performed for 18 common inhalant allergens to determine the presence of atopy. Children aged 12-13 years and parents of children aged 6-7 years were asked to complete questionnaire assessing allergic diseases. The cut-off levels of total IgE were determined by analyzing receiver operating characteristic curves. The median total IgE level was 86.7 kU/L (range: 1.5-4,523.1) in 3,753 children aged 6-7 years and 94.7 kU/L (range: 1.5-3,000.0) in 3,930 children aged 12-13 years. Total IgE concentrations were higher in children with atopy or allergic diseases than in those without (all P < 0.001). At the cut-off value of 127.7 kU/L, sensitivity, specificity, and positive and negative predictive values (PPV and NPV) were 67.1%, 75.4%, 65.4%, and 76.7%, respectively, in elementary schoolchildren. At the cut-off value of 63.0 kU/L, sensitivity, specificity, PPV, and NPV were 81.9%, 66.6%, 75.0%, and 75.1%, respectively, in middle schoolchildren. PPV and NPV were ≥ 70% when cut-offs of 258.8 kU/L and 38.4 kU/L were used for the diagnosis of atopy in 6-7 year-olds and 12-13 year-olds, respectively. This nationwide population-based study provided the first normal reference ranges of total IgE in Korean schoolchildren.

Exposure to mould allergens and rhinoconjunctivitis in Korean children.

BACKGROUND: Although rhinitis is the most common allergic disease in children, few studies have explored the causal relationships between mould allergens and rhinitis. Thus, this study aimed to identify factors, especially prior exposure to mould allergens, related to rhinitis and rhinoconjunctivitis in Korean children. METHODS: Subjects in this study were 12- to 13-year-old children from 40 national middle schools who were participants of the International Study of Asthma and Allergies in Childhood (ISAAC) study in Korea. A total of 3852 children who completed the ISAAC questionnaire in 2010 and underwent a skin prick test (SPT) and blood test were enrolled in this study. RESULTS: The prevalence of symptoms suggestive of rhinitis or rhinoconjunctivitis in last 12 months was 42.7% and 19.4%, respectively. A parental history of allergies (OR = 2.03, 95% CI = 1.75-2.35; OR = 2.55, 95% CI = 2.13-3.06), visible mould or dampness (OR = 1.28, 95% CI = 1.09-1.51; OR = 1.23, 95% CI = 1.00-1.51), previous exposure to mould allergens (OR = 4.53, 95% CI = 2.32-8.84; OR = 4.98, 95% CI = 2.43-10.20), total IgE levels ≥78 kU/l (OR = 1.44, 95% CI = 1.22-1.69; OR = 1.99, 95% CI = 1.60-2.48) were risk factors for rhinitis and rhinoconjunctivitis. CONCLUSIONS: This study suggested that previous exposure to mould allergens more influenced rhinitis and rhinoconjunctivitis than visible mould or dampness, and that total IgE levels of ≥78 kU/l, which was the criterion suggested in a study of Asian children, were risk factors for rhinitis diseases.

Readmission rates of South Korean psychiatric inpatients by inpatient volumes per psychiatrist.

BACKGROUND: Readmission rates of psychiatric inpatients are higher in South Korea than other Organization for Economic Co-operation and Development (OECD) countries. In addition, the solution for readmission control is deficient based on the characteristics of the South Korean National Health Insurance (NHI) system. Therefore, it is necessary to identify ways to reduce psychiatric inpatient readmissions. This study investigated the relationship between inpatient volume per psychiatrist and the readmission rate of psychiatric inpatients in South Korea. METHOD: We used NHI claim data (N = 37,796) from 53 hospitals to analyze readmission within 30 days for five diagnosis (organic mental disorders, mental and behavioral disorders due to psychoactive substance use, schizophrenia, mood disorders, neurotic disorders, and stress-related and somatoform disorders) between 2010 and 2013. We performed χ2 and analysis of variance tests to investigate associations between patient and hospital-level variables and readmission within 30 days. Finally, generalized estimating equation (GEE) models were analyzed to examine possible associations with readmission. RESULTS: Readmissions within 30 days accounted for 1,598 (4.5 %) claims. Multilevel analysis demonstrated that inpatient volume per psychiatrist were inversely related with readmission within 30 days (low odds ratio [OR]: 0.38, 95 % confidence interval [CI]: 0.28-0.51; mid-low OR: 0.48, 95 % CI: 0.36-0.63; mid-high OR: 0.55, 95 % CI: 0.44-0.69; Q4 = ref). The subgroup analysis by diagnosis revealed that both "schizophrenia, schizotypal, and delusional disorders" and "mood disorders" had inverse relationships with readmission risk for all volume groups. CONCLUSIONS: We observed an inverse association between inpatient volume per psychiatrist and the 30-day readmission rate of psychiatric inpatients, suggesting that it could be a useful quality indicator in mental health care.

The association between hypovitaminosis D and pediatric allergic diseases: A Korean nationwide population-based study.

BACKGROUND: There is still considerable disagreement regarding the role of vitamin D in the development or exacerbation of allergic diseases. OBJECTIVE: To investigate the association between serum vitamin D levels and recent symptoms of allergic diseases in elementary schoolchildren. METHODS: A nationwide cross-sectional survey was conducted in children ages 6-7 years from 45 randomly selected elementary schools. The presence of atopic dermatitis (AD) or asthma was defined as medical treatment of children for AD or asthma within 12 months of the survey. The presence of allergic rhinitis (AR) was defined as medical treatment for AR during the past 12 months and a positive skin test response. Current AD was defined as confirmed eczema on physical examination. Serum 25-hydroxyvitamin D (25[OH]D) was measured by chemiluminescent immunoassay. RESULTS: Questionnaire data and blood samples were collected from 3720 children. The overall prevalence rates of vitamin D insufficiency (20-29 ng/mL) and deficiency (<20 ng/mL) were 64.0% and 18.4%, respectively. For a 1 ng/mL decrease in 25(OH)D, the adjusted odds ratio (aOR) for AR was 1.020 (95% confidence interval [CI], 1.002-1.040) and the aOR for current AD was 1.027 (95% CI, 1.006-1.047). For each 1 ng/mL decrease in 25(OH)D, the aOR for positive skin-prick test reactivity was 1.013 (95% CI, 1.000-1.027). No significant association between vitamin D level and the prevalence of asthma was observed. CONCLUSIONS: A high prevalence of vitamin D deficiency and insufficiency was found in Korean elementary schoolchildren, and low vitamin D levels were associated with recent symptoms of AD and AR.

Risk factors of atopic dermatitis in Korean schoolchildren: 2010 international study of asthma and allergies in childhood.

BACKGROUND & OBJECTIVE: We aimed to analyse the risk factors of atopic dermatitis (AD) in Korean schoolchildren in 2010. METHODS: A nationwide, cross-sectional study was conducted in children aged 6-7 years and adolescents aged 12-13 years who were randomly selected. Information was obtained through a Korean version of the International Study of Asthma and Allergies in Childhood questionnaire (ISAAC), and skin prick tests were performed. AD-diagnosed children were selected for risk factor analysis by using logistic regression. RESULTS: We enrolled 4,003 children (M/F = 2,021/ 1,982) in aged 6-7 years and 4,112 children (M/F = 2,029/2,083) in 12-13 years. In children aged 6-7 years, the lifetime prevalence of AD diagnosis was 35.6% (N = 1,424). On the other hand, in the 12 to 13 year age group, the lifetime prevalence of AD diagnosis was 24.2% (N = 981). In the univariate logistic regression analysis in 6-7 year-old children, possible risk factors were atopy, a parental history of allergic disease, the use of antibiotics during infancy, a history of having moved into a newly built house during infancy, the presence of visible mould in the house, and remodelling of house within 12 months. The statistical significance persisted after adjustment. However, antibiotic use during infancy and remodelling within 12 months showed no statistical significance as a risk factor for AD. In contrast, multivariate logistic regression analysis in adolescents demonstrated that female sex, atopy, a parental history of allergic diseases, the presence of visible mould in the house, and a history of having moved into a newly built house during infancy was associated with AD. There was no significant association between AD and other risk factors. CONCLUSION: In Korean schoolchildren, risk factors such as atopy, the presence of parental allergic diseases, moving into a newly built house during infancy and visible mould in the house were associated with AD.

Different socioeconomic inequalities exist in terms of the prevention, diagnosis and control of diabetes.

OBJECTIVE: To evaluate socioeconomic disadvantage in prevalence, awareness and control of diabetes in universal coverage healthcare system. METHODS: Data from the fifth KNHNES (2010-12) were analyzed. The sample included 10,208 individuals with diabetes aged ≥30 years. Diabetes was defined by (i) a self-reported previous diagnosis of diabetes made by a physician, (ii) the current use of oral hypoglycaemic agents and/or insulin or (iii) fasting plasma glucose ≥126 mg/dl. Subjects who were first diagnosed by the survey were classified as 'undiagnosed'. Inadequate control was defined as HbA1c ≥6.5%. RESULTS: It was estimated that 26.4% of subjects with diabetes were not aware of their condition and 73.1% of cases of diabetes were not adequately controlled. Inequalities in socioeconomic status were related to the diabetes prevalence in both men and women. Educational level was not predictive of diagnosis or control in men or women, whereas lower household income level was associated with diagnosis in men only. CONCLUSIONS: This widespread lack of awareness and inadequate control underscore the need for intensive efforts in these domains. Monitoring is expected to highlight the gaps in the preventive and care services offered to the most vulnerable individuals and it may induce governments and practitioners to address these issues.

Indoor environmental factors associated with wheezing illness and asthma in South Korean children: phase III of the International Study of Asthma and Allergies in Childhood.

BACKGROUND: The relationship between exposure to indoor environmental pollutants and incidence of asthma and wheezing illness in children is unclear. This study aimed to clarify this relationship by identifying the risk factors associated with these conditions in South Korean children aged 6-7 years. METHODS: The parents or guardians of 3810 children aged 6-7 years who had participated in the International Study of Asthma and Allergies in Childhood and met the study criteria completed validated questionnaires regarding their children's asthma and wheezing illness, risk factors and exposure to indoor pollutants. The data were subjected to chi-square and multivariate logistic regression analysis to identify the factors significantly associated with asthma and wheezing illness. RESULTS: Parental history of allergic disease (odds ratio [OR]: 1.729; 95% confidence interval [CI]: 1.447-2.066), living on the basement or semi-basement floor (OR: 1.891; 95% CI: 1.194-2.996) and living in housing that had been remodeled within the last 12 months (OR: 1.376; 95% CI: 1.101-1.720) were found to be significantly associated with wheezing illness. Parental history of allergic disease (OR: 2.189; 95% CI: 1.483-3.231), male sex (OR: 1.971; 95% CI: 1.369-2.838) and positive skin prick test (SPT) result (OR: 1.583; 95% CI: 1.804-3.698) were found to be significantly associated with current asthma. CONCLUSIONS: Although the risk factors for current asthma appear to be more related to the non-modifiable risk factors like sex, parental history of allergic diseases, SPT, the two groups are associated with exposure to modifiable indoor environmental factors.

Clinical Effects of a Home Care Pilot Program for Patients with Type 1 Diabetes Mellitus: A Retrospective Cohort Study.

BACKGRUOUND: Given the importance of continuous self-care for people with type 1 diabetes mellitus (T1DM), the Ministry of Health and Welfare of Korea launched a pilot program for chronic disease management. Herein, we applied a home care pilot program to people with T1DM to investigate its effects. METHODS: This retrospective cohort study was conducted at a single tertiary hospital (January 2019 to October 2021). A multidisciplinary team comprising doctors, nurses, and clinical nutritionists provided specialized education and periodically assessed patients' health status through phone calls or text messages. A linear mixed model adjusting for age, sex, and body mass index was used to analyze the glycemic control changes before and after implementing the program between the intervention and control groups. RESULTS: Among 408 people with T1DM, 196 were enrolled in the intervention group and 212 in the control group. The reduction in glycosylated hemoglobin (HbA1c) after the program was significantly greater in the intervention group than in the control group (estimated marginal mean, -0.57% vs. -0.23%, P=0.008); the same trend was confirmed for glycoalbumin (GA) (-3.2% vs. -0.39%, P<0.001). More patients achieved the target values of HbA1c (<7.0%) and GA (<20%) in the intervention group than in the control group at the 9-month follow-up (34.5% vs. 19.6% and 46.7% vs. 28.0%, respectively). CONCLUSION: The home care program for T1DM was clinically effective in improving glycemic control and may provide an efficient care option for people with T1DM, and positive outcomes are expected to expand the program to include more patients.

Time to follow up after an abnormal finding in organized gastric cancer screening in Korea.

BACKGROUND: The prognosis for an abnormal medical finding is affected by both early detection and adherence to the presecribed schedule for follow-up examinations. In this study, we examined the time to follow up after an abnormal finding and determined the risk factors related to delays in follow up in a population-based screening program. METHODS: The study population consisted of patients who were newly diagnosed with gastric cancer through a gastric cancer screening program sponsored by the National Cancer Screening Program (NCSP) in 2005. Due to the skewed nature of the distribution of time to follow up, medians and interquartile ranges (IQR) are presented, and we analyzed the number of days preceding the follow-up time as a binary variable (≤ 90 days or >90 days). We used logistic regression analyses to evaluate the risk factors for a long delay. RESULTS: The median number of days to follow-up initiation after an abnormal finding was 11 (IQR 7-27); 13.9% of the patients with gastric cancer obtained their follow-up evaluation more than 90 days. Age, type of health insurance, screening method, and screening results were risk factors for delays in follow up. CONCLUSIONS: This study examined delays from the time of the discovery of an abnormal finding to time of the follow-up evaluation. Because inadequate follow up of abnormal exam results undermines the potential benefits of cancer screening, it is important to organize services that minimize delays between cancer screening and treatment.

Predictors and outcomes of feeling of insufficient consultation time in cancer care in Korea: results of a nationwide multicenter survey.

BACKGROUND: Shared decision making and an integrative approach is expected to result in better outcomes, but might require more time. While ensuring that sufficient consultation time is essential to quality cancer care, it is not clear whether cancer patients feel that the amount of consultation time with their oncologists is sufficient. METHODS: Data were collected from 2,556 cancer patients on their perceived and preferred consultation time, and included potential predictors, such as socio-demographics, clinical, behavioral, and quality-of-life factors, as well as potential outcomes, including unmet patient needs, trust in doctor, and satisfaction. The feeling of insufficient consultation time was defined as the perception that consultation time is less than the preferred consultation time; multivariate analyses were used for identification of predictors and comparison of outcomes. RESULTS: Overall, 37.1% felt that consultation time was less than preferred. Younger age, female sex, higher education level, having national health insurance, having been diagnosed with less common cancers, and having anxiety/depression were significantly associated with feelings of insufficient consultation time. Subjects with a feeling of insufficient consultation time reported higher current needs for information, physical symptoms, and psychological problems. They also reported less trust in their physician, lower overall satisfaction, and lower intention to continue treatment at the current cancer center. CONCLUSION: This study illustrated that high-quality cancer care, characterized by shared decision making and an integrative approach, seems to be related to sufficient consultation time that meets the individual's subjective needs, and measures should be taken to ensure sufficient consultation time.

Prevalence of immediate-type food allergy in Korean schoolchildren: a population-based study.

Although the prevalence and causes of food allergy (FA) vary by geographic location, large well-designed epidemiological studies in Asia are lacking. The purpose of this study was to evaluate the prevalence of immediate-type FA in the general population of Korean schoolchildren. A population-based, cross-sectional study was conducted in 2010 using a stratified two-stage cluster-sampling design. In this survey, children aged 6-7 years and 12-13 years were randomly selected, and the presence of FA was determined by a questionnaire survey and assessment of specific IgE. After adjustment for missing data, 3907 children aged 6-7 years and 3975 students aged 12-13 years who completed the questionnaire were included in this study. In children aged 6-7 years, the prevalence of confirmed immediate-type FA was 0.3%, and the prevalence of possible immediate-type FA was 0.3%. By contrast, 0.6 and 1.0% of children aged 12-13 years had confirmed immediate-type FA and possible immediate-type FA, respectively. In 6- to 7-year-old children, egg was the most frequent causative food associated with a confirmed or possible immediate-type FA. In 12- to 13-year-old children, crustaceans were the most frequent cause of confirmed immediate-type FA, and fruit was most frequently involved in possible immediate-type FA. This is the first nationwide population-based study of FA in Korean schoolchildren. Unlike in western countries, the prevalence of immediate-type FA seems to be low. In 12- to 13 year-old children with confirmed immediate-type FA, peanuts/tree nuts are not common causes, whereas crustaceans are frequent triggers.

The gap between physicians and the public in satisfaction with the National Health Insurance system in Korea.

The Korean National Health Insurance (NHI) system was an unprecedented accomplishment that was achieved in a short period of time. In this study, we sought to identify gaps between physicians and the public with respect to attitudes toward the NHI system in Korea. The study population was derived from the 2008 Korean Medical Association Survey, which was conducted to investigate satisfaction with and perceptions of the NHI system among physicians (n = 961) and the public (n = 935). Only 6.5% of the physicians were satisfied with NHI system, and 71.5% were dissatisfied with it. In contrast, 28.3% of the public were satisfied with the NHI system, and 21.4% were dissatisfied. The level of dissatisfaction expressed by physicians (2.03 ± 0.91 on a five-point scale) was also higher than that expressed by the public (3.06 ± 0.84). Despite rapid growth of NHI system, a large gap in satisfaction exists between physicians and the public.

Who participates in the gastric cancer screening and on-time rescreening in the National Cancer Screening Program? A population-based study in Korea.

Gastric cancer (GC) screening is a major challenge in countries where the disease is highly prevalent. This study was conducted to identify the factors associated with participation in GC screening and on-time rescreening among the average-risk population in Korea. The study population was derived from the National Cancer Screening Program database. The population for this study was 22 913 618 individuals aged ≥40 years who had been invited to participate in a GC screening program from 2005 to 2006. We determined whether these individuals had attended the GC screening program and which method - an upper gastrointestinal series (UGIS) or endoscopy-they underwent. We followed the participants to determine whether they had a second GC screening after 2 years. The overall participation rate in the GC screening was 20.5%. More people underwent UGIS than endoscopy. Individuals who had been screened by endoscopy rather than UGIS were more likely to be younger, male, or those who were National Health Insurance (NHI) beneficiaries with a higher premium rate. Of those who underwent baseline screening, 59.4% participated in a rescreening program 2 years later. NHI beneficiaries with a higher premium rate were significantly more likely to be rescreened than medical aid recipients. The results from this study showed that the UGIS were more commonly used in organized GC screenings in Korea, and those who underwent UGIS were more likely to return for subsequent screening compared to those who underwent an endoscopy.

Sensitization to aeroallergens in Korean children: a population-based study in 2010.

We performed this study to assess the prevalence of sensitization to aeroallergens and to analyze the difference between prevalence rates according to children's ages and residential areas. In this nationwide cross-sectional study, first grade students of 45 elementary schools and 40 middle schools were randomly selected, and skin prick tests were performed for 18 inhalant allergens between October and November 2010. Of 7,829 analyzed subjects, 3,753 (47.9%) were sensitized to at least one aeroallergen. Sensitization to Dermatophagoides farinae was found to be the most prevalent in elementary schoolchildren (32.4%), followed by Dermatophagoides pteronyssinus, Tyrophagus putrescentiae, Japanese hop, and oak. In middle schoolchildren, D. pteronyssinus yielded the highest prevalence (42.7%), followed by D. farinae, T. putrescentiae, Japanese hop, and cat. In middle schoolchildren, the sensitization rate to aeroallergens in metropolitan, urban, and rural areas was 57.2%, 54.3%, and 49.8%, respectively (P = 0.019). In this age group, the sensitization rate in low, middle, high, and very high income groups was 53.8%, 51.8%, 59.0%, and 59.6%, respectively (P = 0.002). In conclusion, the sensitization rate is 47.9% and house dust mite is the most prevalent allergen in the pediatric population in Korea. The rate is higher in metropolitan areas and the highest income group than in rural areas and low income groups.