Reference Standard for Digital Infrared Thermography of the Surface Temperature of the Lower Limbs.

Digital infrared thermographic imaging (DITI) is a supplementary diagnostic technique to visualize the surface temperature of the human body. However, there is currently no reference standard for the lower limbs for accurate diagnosis. In this study, we performed DITI on the lower limbs of 905 healthy Korean volunteers (411 males and 494 females aged between 20 and 69 years) to obtain reference standard data. Thermography was conducted on the front, back, lateral sides, and sole area, and 188 regions of interest (ROIs) were analyzed. Additionally, subgroup analysis was conducted according to the proximity of ROIs, sex, and age groups. The mean temperatures of ROIs ranged from 24.60 ± 5.06 to 28.75 ± 5.76 °C and the absolute value of the temperature difference between both sides reached up to 1.06 ± 2.75 °C. According to subgroup analysis, the sole area had a significantly lower temperature than any other areas, men had higher temperatures than women, and the elderly had higher temperatures than the young adults except for the 20s age group (p < 0.001, respectively). This result could be used as a foundation for the establishment of a reference standard for DITI. Practical patient DITI can be accurately interpreted using these data, and it can serve as a basis for further scientific research.

Maternal and Neonatal Risk Factors Affecting the Occurrence of Neurodevelopmental Disorders: A Population-Based Nationwide Study.

To investigate the maternal and neonatal risk factors related to pregnancy and birth affecting the occurrence of neurodevelopmental disorders to their children using the medical claim data for the whole population. The study was conducted on all the babies born in Korea from 2005 to 2009 based on data from the National Health Information Database. All birth records were tracked from birth to December 31, 2015. To analyze factors related to the mother, data related to the mother of the newborn were collected. Increased maternal age was found to increase the risk of cerebral palsy (adjusted odds ratio [aOR] = 1.46) and autism spectrum disorder (aOR = 1.48), while lowering the risk of intellectual disability (aOR = 1.83) and speech and language impairment (aOR = 1.41) compared with the reference group aged 25 to 29 years old. The incidence affected by socioeconomic factors varied according to the types of disorders. Among various risk factors, prematurity or low birth weight, problems associated with amniotic fluid or amniotic membrane, preeclampsia or eclampsia, and cesarean section affect the incidence of neurodevelopmental disorders. To reduce the incidence or severity of neurodevelopmental disorders, a better understanding of the risk factors of neurodevelopmental disorders is important. The results of this study can be used as basic data to help such understanding.

Anemia Is a Risk Factor for the Development of Ischemic Stroke and Post-Stroke Mortality.

BACKGROUND: anemia is known to be a risk factor for developing ischemic stroke in long-term follow-up studies, and it is also known to increase the risk of death in ischemic stroke patients. We aimed to determine the association of anemia with the risk of ischemic stroke and the risk of death after ischemic stroke. METHODS: The study included patients from National Health Insurance Service cohort, from January 2005 to December 2015. Anemia patients were defined as those with confirmed diagnostic codes and related medications in the sample cohort, and patients under the age of 18 were excluded. To perform a comparative analysis with the control group, twice as many patients were extracted by propensity score matching. The effects of anemia on the development of ischemic stroke were analyzed. RESULTS: A total of 58,699 patients were newly diagnosed with anemia during the study period. In anemia group, the rate of ischemic stroke occurring within 1 year was 0.550%, and the rate was 0.272% in the control group. The odds ratio of anemia related to ischemic stroke was 1.602 (95% confidence intervals (CI) 1.363-1.883). During the follow-up period, 175 out of 309 (56.6%) died in anemia group, and 130 out of 314 (41.4%) died in control group. The anemia group showed a higher risk of death than the control group (Hazard ratio 1.509, 95% CI 1.197-1.902). CONCLUSION: Analysis of the nationwide health insurance data revealed that anemia is one of the risk factors for the development of ischemic stroke, and also an independent prognostic factor affecting post-stroke mortality.

Incidence and Clinical Outcomes of Febrile Neutropenia in Adult Cancer Patients with Chemotherapy Using Korean Nationwide Health Insurance Database.

PURPOSE: The aim of this study was to evaluate the episodes of febrile neutropenia (FN) in patients with gastric cancer (GC), colorectal cancer (CRC), lung cancer (LC), and breast cancer (BC); and to identify the incidence and trends of admission rates, as well as factors affecting mortality. MATERIALS AND METHODS: Using nationwide claims data, all new admissions to hospitals for FN were selected. We evaluated the incidence of FN and mortality-related clinical factors in adult cancer patients who received cytotoxic chemotherapy from January 2004 to December 2013. RESULTS: While the incidence of FN increased, the length of hospitalization decreased in Korea. The incidence of FN was 19.8% in LC patients, 15.5% in GC patients, 13.3% in BC patients, and 9.5% in CRC patients. The overall in-hospital mortality of FN was 12.9% and showed a decreasing trend. Admission rates to intensive care units and in-hospital mortality were the highest for lung cancer (15.2% and 19.3%, respectively). Age and sepsis syndrome were risk factors for in-hospital mortality for all cancer types. CONCLUSION: Careful observation and active prophylaxis should be considered for patients at high risk of FN.

Dynamic Chronological Changes in Serum Triglycerides Are Associated With the Time Point for Non-alcoholic Fatty Liver Disease Development in the Nationwide Korean Population Cohort.

Background: We investigated the effects of anthropometric, laboratory, and lifestyle factors on the development of non-alcoholic fatty liver disease (NAFLD) in a nationwide, population-based, 4-year retrospective cohort. Methods: The propensity score-matched study and control groups contained 1,474 subjects who had data in the Korean National Health Insurance Service-National Sample Cohort in 2009, 2011, and 2013. NAFLD was defined using medical records of a diagnosis confirmed by primary clinicians and meeting two previously validated fatty liver prediction models. Chronological changes in anthropometric variables, laboratory results, and lifestyle factors during two periods were compared between patient and control groups in order to find out parameters with consistent dynamics in pre-NAFLD stage which was defined as period just before the NAFLD development. Results: Among the 5 anthropometric, 10 laboratory, and 3 lifestyle factors, prominent chronological decremental changes in serum triglycerides were consistently observed during the pre-NAFLD stage, although the degrees of changes were more predominant in men (-9.46 mg/dL) than women (-5.98 mg/dL). Furthermore, weight and waist circumference changes during the pre-NAFLD stage were noticeable only in women (+0.36 kg and +0.9 cm for weight and waist circumference, respectively), which suggest gender difference in NAFLD. Conclusion: Early screening strategies for people with abrupt chronological changes in serum triglycerides to predict NAFLD development before the progression is recommended.

Epidemiology of Congenital Bleeding Disorders: a Nationwide Population-based Korean Study.

BACKGROUND: Except for data in the Korea Hemophilia Foundation Registry, little is known of the epidemiology of congenital bleeding disorders in Korea. METHODS: Data were obtained from the Korean Health Insurance Review and Assessment Service (HIRA) database. RESULTS: From 2010 to 2015, there were 2,029 patients with congenital bleeding disorders in the Korean HIRA database: 38% (n = 775) of these patients had hemophilia A (HA), 25% (n = 517) had von Willebrand disease (vWD), 7% (n = 132) had hemophilia B (HB), and 25% (n = 513) had less common factor deficiencies. The estimated age-standardized incidence rate (ASR) of HA and HB was 1.78-3.15/100,000 and 0.31-0.51/100,000, respectively. That of vWD was 1.38-1.95/100,000. The estimated ASR of HA showed increase over time though the number of new patients did not increase. Most patients with congenital bleeding disorders were younger than 19 years old (47.8%), and most were registered in Gyeonggi (22.1%) and Seoul (19.2%). CONCLUSION: This is the first nationwide population-based study of congenital bleeding disorders in Korea. This study provides data that will enable more accurate estimations of patients with vWD. This information will help advance the comprehensive care of congenital bleeding disorders. We need to continue to obtain more detailed information on patients to improve the management of these diseases.

Bone metastasis and skeletal-related events in patients with solid cancer: A Korean nationwide health insurance database study.

Bone is one of the most common sites of metastasis from advanced solid tumors. Bone metastasis is a leading cause of pain and increases the risk of skeletal-related events (SREs) in cancer patients. In addition to affecting the quality of life, it also increases the medical costs and mortality risk. We aimed to examine the occurrence of bone metastasis and SREs in Korean cancer patients using a nationwide health database. Using claims data from the National Health Insurance Service-National Sample Cohort (2002-2013), we extracted the data of bone metastasis patients diagnosed with any of the seven major cancers in Korea from January 2002 to December 2010. Selected SREs included pathologic fracture, spinal cord compression, radiation therapy, and palliative bone surgery. We used time-to-event analysis to estimate patient survival after bone metastasis. A total of 21,562 newly diagnosed cancer patients were identified; bone metastases developed in 1,849 patients (breast cancer, 18.8%; prostate cancer, 17.5%; lung cancer, 13.7%). The median time from primary cancer diagnosis to bone metastasis was 18.9 months. The cumulative incidence of SREs was 45.1% in all bone metastasis patients. The most common cancer type was lung cancer (53.4%), followed by liver (50.9%), prostate (45.9%), breast (43.6%), and colorectal (40.2%) cancers. Almost all SREs developed 1 month after bone metastasis, except in patients with breast and prostate cancers (median: 5.9 months in breast cancer and 4.7 months in prostate cancer). Survival duration after the development of bone metastasis was < 6 months in stomach, liver, colorectal, and lung cancer patients. Breast and prostate cancer patients survived for > 1 year after the occurrence of SREs. This study reveals the epidemiology of bone metastasis and SREs in Korean cancer patients, and the findings can be used to assess the actual bone health status of cancer patients.

Hemoglobin Concentration Reference Interval Revisited: a Nationwide Study from Korea.

BACKGROUND: Anemia is a common cause among the elderly for increased mortality. Hemoglobin concentration can be affected by many factors, but the reference interval defined by the World Health Organization has not been adjusted for the previous half century. METHODS: Through using the dataset generated by the National Health Insurance (NHI) health screening program of Republic of Korea, here we attempt to present a close to actual hemoglobin concentration of the Korean population. Between January 2009 and December 2013, a total of 57,409,872 health screening events were registered in the NHI database. Following the exclusion criteria, 6,759,566 participants were enrolled for analyses. RESULTS: Significant portion of the study population was considered 'anemic', while the mean value (2.5% ~ 97.5%) of hemoglobin concentration from the study was 14.8 (12.5 ~ 16.8) g/dL in men and 12.8 (10.6 ~ 14.7) g/ dL in women. Concordant results of hemoglobin concentration declining with age were observed as previous studies have described, supporting the need for separate, possibly lower cutoff in the elderly. CONCLUSIONS: A considerable portion of the participants being categorized as anemia contests the accuracy of the current lower cutoff for anemia. From a large representative dataset, the need for adjustment to the lower cutoff for anemia is suggested.

The nature of rehabilitation services provided to children with cerebral palsy: a population-based nationwide study.

BACKGROUND: Cerebral palsy (CP) is a serious neurodevelopmental disorder that occurs in childhood and requires a range of treatments over a person's lifetime. The aims of this study were to investigate the nature of the rehabilitation treatments provided to children with CP and to determine if there were any changes in patterns over time. METHODS: From 2003 to 2013, the nature of rehabilitation treatment was analyzed for children diagnosed with CP. In addition, the medical data of rehabilitation treatments over a 10-year period (from birth to nine years of age) were analyzed for children born in 2004 diagnosed with CP. Furthermore, we analyzed whether there was a difference in the costs of medical expenditures according to family income. All studies were based on data from the Korean National Health Information Database. RESULTS: It was found that, in recent years, rehabilitation therapy and spasticity treatment of children with CP have started being performed at a younger age than in the past. Among the children with CP born in 2004, 28.6% had physical therapy and 25.4% had occupational therapy on an inpatient basis; 81.3% had physical therapy and 62.2% had occupational therapy on an outpatient basis. Additionally, 22.2% of children received botulinum toxin injection therapy at least once. The numbers of children receiving rehabilitation therapy and botulinum toxin injection were highest at 1-5 years of age and 6-7 years of age, respectively. The expenditure on rehabilitation therapy was not affected by the economic level of the family. CONCLUSION: This study investigated the nature of rehabilitation services provided to children with CP. More recently, the treatment of children with CP has started to be performed earlier than in the past. In addition, it was confirmed that the nature of rehabilitation treatment for children with CP changed according to age. Based on these results, services and health policies may need to be better organized to enhance the benefits to children with CP.

Changes in the Diagnostic Efficiency of Thyroid Fine-Needle Aspiration Biopsy during the Era of Increased Thyroid Cancer Screening in Korea.

PURPOSE: The volume of thyroid cancer screening and subsequent thyroid fine-needle aspiration (FNA) have rapidly increased in South Korea. We analyzed the thyroid cancer diagnoses/thyroid FNA ratio according to the annual number of FNA to evaluate changes in the diagnostic efficiency of FNA. MATERIALS AND METHODS: This was a nationwide population-based retrospective cohort study. The overall thyroid cancer diagnoses/thyroid FNA ratio and annual incremental thyroid cancer diagnoses/incremental thyroid FNA ratio were indirectly calculated using data obtained from the Korea Central Cancer Registry database and the Korean National Health Insurance Service claims database from 2004 to 2012. Pearson correlation analyses were performed to evaluate the strength of linear associations between variables. RESULTS: The number of thyroid FNA increased from 28,596 to 177,805 (6.2-fold increase) from 2004 to 2012. The overall thyroid cancer diagnoses/thyroid FNA ratio decreased from 36.5% in 2004 to 25.1% in 2012 and was negatively correlated to the number of FNA (R=‒0.977, p < 0.001). The annual incremental thyroid cancer diagnoses/incremental thyroid FNA ratios (range, 15.3% to 30.7%) were always lower than the overall thyroid cancer diagnoses/thyroid FNA ratio in each year and also worsened according to the increase in the number of FNA (R=‒0.853, p=0.007). CONCLUSION: The diagnostic performance of both overall and annual incremental thyroid FNA worsened, whereas the number of thyroid FNA procedures increased. More sophisticated indications for FNA are required to improve its diagnostic efficiency, considering the increased burden of screening-detected thyroid nodules.

Panoramic radiography can be an effective diagnostic tool adjunctive to oral examinations in the national health checkup program.

PURPOSE: We investigated correlations between the findings of oral examinations and panoramic radiography in order to determine the efficacy of using panoramic radiographs in screening examinations. METHODS: This study included patients who visited dental clinics at National Health Insurance Service (NHIS) Ilsan Hospital for checkups during 2009-2015 and underwent panoramic radiographic examinations within 1 year prior to the oral examinations. Among the 48,006 patients who received checkups, 1,091 were included in this study. The data were evaluated using the Cohen kappa and interrater agreement coefficients. Accuracy, sensitivity, and specificity were calculated using data from the panoramic radiographs as true positive diagnoses. RESULTS: The interrater agreement coefficient for occlusal caries was 28.8%, and the Cohen kappa coefficient was 0.043 between the oral and panoramic radiographic examinations. Root caries and subgingival calculus were only found on the radiographs, while gingival inflammation was found only by the oral examinations. The oral examinations had a specificity for detecting occlusal dental caries of 100%, while their sensitivity for proximal dental caries and supragingival calculus was extremely low (14.0% and 18.3%, respectively) compared to the panoramic radiographic examinations. The oral examinations showed a relatively low sensitivity of 66.2% and a specificity of 43.7% in detecting tooth loss compared with panoramic radiography. CONCLUSIONS: Panoramic radiography can provide information that is difficult to obtain in oral examinations, such as root caries, furcation involvement, and subgingival calculus, which are factors that can directly affect the survival rate of teeth. It therefore seems reasonable and necessary to add panoramic radiography to large-scale health checkup programs such as that provided by the NHIS.

Cost of Rehabilitation Treatment of Patients With Cerebral Palsy in Korea.

OBJECTIVE: To investigate rehabilitation treatment cost of patients with cerebral palsy (CP) according to age. METHODS: We analyzed the cost of rehabilitation treatment from 2007 to 2013 for patients diagnosed with CP by sourcing data from the National Health Information Database. RESULTS: While the number of recently born children requiring rehabilitation treatment has decreased, the number of patients requiring this treatment in other age groups has gradually increased. In addition, annual physical therapy, occupational therapy, hydrotherapy, and botulinum toxin injection treatment costs per person have increased. On the other hand, the number of orthopedic surgeries and selective dorsal rhizotomy performed has decreased. CONCLUSION: This study investigated trends in the cost of treatment for patients with CP. This study can be used as a basis to provide treatment support for patients with CP.

Disability Registration State of Children With Cerebral Palsy in Korea.

OBJECTIVE: To investigate the disability registration state of children with cerebral palsy (CP) in Korea. METHODS: Based on the National Health Information Database, the disability registration state was examined for brain lesion disability and other possible complicated disabilities accompanying brain disorder in children diagnosed with CP aged up to 5 years old who were born between 2002 and 2008. RESULTS: Of children diagnosed with CP, 73.1% were registered as having brain lesion disability for the first time before they turned 2 years old. The younger the children, the more likely they will have 1st and 2nd degree disability. However, when the age of children is increased, such likelihood is decreased. The percentage of children registered as having overlapping disabilities was 7%-20%. CONCLUSION: It is important to establish a more accurate standard to rate disability and provide national support systems for children with CP with various severities and multiple disabilities. By reorganizing the current disability registration system for pediatric brain lesions, the system could serve as a classification standard to provide medical and social welfare services.

Changes in Antimicrobial Usage Patterns in Korea: 12-Year Analysis Based on Database of the National Health Insurance Service-National Sample Cohort.

National antimicrobial usage and prescription patterns during the 12 years from 2002 to 2013 were analyzed using the National Health Insurance Service-National Sample Cohort. Antimicrobial usage was analyzed by major illness, sex, age, area of residence, income rank, diagnosis, and type of medical institution for each year. Total antimicrobial prescriptions increased from 15.943 daily defined dose (DDD)/1,000 inhabitants/day in 2002 to 24.219 in 2013. In 2013, 72% of total prescriptions were administered in clinics. Antimicrobials were most frequently prescribed to children younger than 10 years, followed by adults aged 70 years or older and those aged 60-69 years. Penicillins and cephems were the most popular classes of antimicrobial used. In 2013, 48% of total antibiotic usage (11.683 DDD/1,000 inhabitants/day) was due to respiratory diseases. After the Korean government has implemented a series of healthcare policies, antibiotic prescription decreased for the treatment of upper respiratory infection, the causative agents are mostly viruses.

Incidence of Cerebral Palsy in Korea and the Effect of Socioeconomic Status: A Population-Based Nationwide Study.

PURPOSE: Cerebral palsy (CP) is a neurodevelopmental disorder that causes serious disability. Prematurity and low birth weight (LBW) are known to be the strongest risk factors of CP. While socioeconomic status (SES) has been found to influence the occurrence of CP, prematurity, and LBW, no studies have investigated this effect in Korea. The aim of this study was to evaluate the incidence of CP, prematurity, and LBW in Korea, as well as the effect of SES thereon. MATERIALS AND METHODS: Data were obtained from the National Health Information Database from 2007 to 2013; persons with a history of CP, prematurity, and LBW were investigated by year. SES was defined in accordance with income quintiles, birth regions, and coverage classification. RESULTS: The incidence of CP decreased over the last five years, despite increased rates of prematurity and LBW. CP incidence was significantly lower in affluent groups than in the most deprived group, although this difference disappeared after controlling for confounders. The incidence of CP was significantly higher in medical aid beneficiaries, even after controlling for confounders. CONCLUSION: CP incidence in Korea has decreased over the last five years, despite an increase in high-risk deliveries. Income level had no effect in CP incidence. These results may aid CP management and prevention policies.

Trends in South Korean antimicrobial use and association with changes in Escherichia coli resistance rates: 12-year ecological study using a nationwide surveillance and antimicrobial prescription database.

The purpose of this study is to determine the correlation between use of antimicrobials, such as fluoroquinolone, cefoxitin, and cefotaxime, and Escherichia coli resistance using a nationwide database. Nationwide data on antimicrobial consumption for 12 years (2002 to 2013) were acquired from a database of subjects (n = 1,025,340) included in the National Health Insurance Service-National Sample Cohort. National antimicrobial resistance rates of E. coli were obtained from the Korean Antimicrobial Resistance Monitoring System, which has been administered by the Korean Centers for Disease Control and Prevention since 2002. Fluoroquinolone-resistance rates of E. coli isolated from general hospitals have continuously increased since 2002 and were correlated with nationwide fluoroquinolone use (r = 0.82, P = 0.0012) or ciprofloxacin use (r = 0.90, P<0.0001). Cefotaxime-resistance rates of E. coli isolated from general hospitals markedly increased since 2008 and were correlated with nationwide cefotaxime use (r = 0.94, P<0.0001) or third-generation cephalosporin use (r = 0.96, P<0.0001). Cefoxitin-resistance rates of E. coli isolated from general hospitals peaked in 2010 and significantly correlated with cephamycin use at a two-year interval (r = 0.64, P = 0.0256). In conclusion, consumption of antimicrobials such as fluoroquinolone, cefoxitin, and cefotaxime is well correlated with the resistance rates of E. coli to these agents. This study provides background data for national antimicrobial management policies to reduce antimicrobial resistance.

Fecal Occult Blood Test Results of the National Colorectal Cancer Screening Program in South Korea (2006-2013).

There has been controversy regarding the clinical utility of fecal occult blood test (FOBT) as a screening tool for colorectal cancer (CRC) in the general population. The purpose of this study was to examine the results of Korea national CRC screening using FOBT from 2006 to 2013 and to evaluate the implementation of the program. We analyzed the results of FOBT, colonoscopy, and the side effects during colonoscopy for the subjects (n = 20,609,909) from the Korea National Health Insurance Cancer Screening database. For evaluation of Korea national CRC screening program implementation over the 8-year period, we calculated uptake rate, FOBT positivity rate, and subsequent test compliance rate. The overall uptake rate was 30.1%, with an increasing pattern from 2006 to 2011. A relatively higher FOBT positivity rate (6.4%) and lower subsequent test compliance rate (46.6%) were observed in comparison to the results previously reported in Western countries. Side effects reported within 3 months period after colonoscopy accounted for 0.17% of all procedures, with bleeding being the most prevalent type. Although the implementation of CRC screening program using FOBT in Korea seems successful, trends in key indicators for Korea national CRC screening program should be monitored continuously.

Association between periodontal disease and non-communicable diseases: A 12-year longitudinal health-examinee cohort study in South Korea.

The National Health Insurance Service-Health Examinee Cohort during 2002 to 2013 was used to investigate the associations between periodontal disease (PD) and the following non-communicable diseases (NCDs): hypertension, diabetes mellitus, osteoporosis, cerebral infarction, angina pectoris, myocardial infarction, and obesity.Univariate and multivariate logistic regression analyses adjusting for potential confounders during the follow-up period-including age, sex, household income, insurance status, residence area, health status, and comorbidities-were used to estimated odds ratios (ORs) with 95% confidence intervals (CIs) in order to assess the associations between PD and NCDs.We enrolled 200,026 patients with PD and 154,824 subjects with a healthy oral status. Statistically, significant associations were found between PD and the investigated NCDs except for cerebral and myocardial infarction after adjusting for sociodemographic and comorbidity factors (P < .05). In particular, obesity (OR = 1.30, 95% CI = 1.04-1.63, P = .022), osteoporosis (OR = 1.22, 95% CI = 1.18-1.27, P < .001), and angina pectoris (OR = 1.22, 95% CI = 1.17-1.27, P < .001) were significantly and positively associated with PD.This longitudinal cohort study has provided evidence that patients with PD are at increased risk of NCDs. Further studies are required to confirm the reliability of this association and elucidate the role of the inflammatory pathway in periodontitis pathogenesis as a triggering and mediating mechanism.