The Association of Perceived Neighborhood Walkability and Environmental Pollution With Frailty Among Community-dwelling Older Adults in Korean Rural Areas: A Cross-sectional Study.

OBJECTIVES: The aim of this study was to evaluate the associations of frailty with perceived neighborhood walkability and environmental pollution among community-dwelling older adults in rural areas. METHODS: The participants were 808 community-dwelling men and women aged 65 years and older in 2 rural towns. Comprehensive information, including demographics, socioeconomic status, grip strength, polypharmacy, perceived neighborhood environment (specifically, walkability and environmental pollution), and frailty, was collected from participants using face-to-face interviews conducted between June and August 2018. Perceived neighborhood walkability was measured using 20 items that were selected and revised from the Neighborhood Environment Walkability Scale, the Neighborhood Walkability Checklist from the National Heart Foundation of Australia, and the Physical Activity Neighborhood Environment Survey. The Kaigo-Yobo Checklist was used to assess participants' frailty. RESULTS: The overall prevalence of frailty in this community-dwelling population was 35.5%. Sex, age, cohabitation status, educational attainment, employment status, grip strength, and polypharmacy were significantly associated with frailty. In the logistic regression analysis, frailty was associated with low perceived neighborhood walkability (adjusted odds ratio [aOR], 0.881; 95% confidence interval [CI], 0.833 to 0.932; p<0.001) and severe perceived neighborhood environmental pollution (aOR, 1.052; 95% CI, 1.017 to 1.087; p=0.003) after adjusting for sex, age, cohabitation status, educational attainment, employment status, monthly income, grip strength, and polypharmacy. CONCLUSIONS: More studies are warranted to establish causal relationships between walkability and environmental pollution and frailty.

The costs of hepatitis A infections in South Korea.

OBJECTIVES: The incidence of hepatitis A infections among young adults has recently increased in South Korea. Although universal vaccination has often been suggested to mitigate the problem, its rationale has not been well-understood. Estimating the societal costs of hepatitis A infections might support the development of intervention strategies. METHODS: We classified hepatitis A infections into eight clinical pathways and estimated the number of occurrences and cost per case for each clinical pathway using claim data from National Health Insurance and several national surveys as well as assumptions based on previous studies. To determine the total costs of a hepatitis A infection, both direct and indirect costs were estimated. Indirect costs were estimated using the human-capital approach. All costs are adjusted to the year 2008. RESULTS: There were 30,240 identified cases of hepatitis A infections in 2008 for a total cost of 80,873 million won (2.7 million won per case). Direct and indirect costs constituted 56.2% and 43.8% of the total costs, respectively. People aged 20-39 accounted for 71.3% of total cases and 74.6% of total costs. Medical costs per capita were the lowest in the 0-4 age group and highest in the 20-29 age group. CONCLUSIONS: This study could provide evidence for development of cost-effective interventions to control hepatitis A infections. But the true costs including uncaptured and intangible costs of hepatitis A infections might be higher than our results indicate.

Trends in the incidence of hospitalized acute myocardial infarction and stroke in Korea, 2006-2010.

This study attempted to calculate and investigate the incidence of hospitalized acute myocardial infarction (AMI) and stroke in Korea. Using the National Health Insurance claim data, we investigated patients whose main diagnostic codes included AMI or stroke during 2006 to 2010. As a result, we found out that the number of AMI hospitalized patients had decreased since 2006 and amounted to 15,893 in 2010; and that the number of those with stroke had decreased since 2006 and amounted to 73,501 in 2010. The age-standardized incidence rate of hospitalized AMI, after adjustment for readmission, was 41.6 cases per 100,000-population in 2006, and had decreased to 29.4 cases in 2010 (for trend P < 0.001). In the case of stroke was estimated at 172.8 cases per 100,000-population in 2006, and had decreased to 135.1 cases in 2010 (for trend P < 0.001). In conclusion, the age-standardized incidence rates of both hospitalized AMI and stroke in Korea had decreased continuously during 2006 to 2010. We consider this decreasing trend due to the active use of pharmaceuticals, early vascular intervention, and the national cardio-cerebrovascular disease care project as the primary and secondary prevention efforts.

Application of revised nursing work index to hospital nurses of South Korea.

PURPOSE: Based on the Revised Nursing Work Index (NWI-R), this research aimed to develop a Korean Hospital General Inpatient Unit-Nursing Work Index (KGU-NWI). This study also aimed to compare the common points and differences between the subfactors of the KGU-NWI and the subfactors from previous studies. METHODS: Based on opinions from 3,151 nurses in Korean hospital general inpatient unit, this research used 57 items of NWI-R and the principal axis factor analysis for deriving subfactors. We evaluated the convergent validity through factor analysis and the content validity of KGU-NWI in terms of the association between nurses' job outcome and the subfactors derived. RESULTS: Six subfactors and 26 items for KGU-NWI were derived from NWI-R. Among them, 'physician-nurse relationship', 'adequate nurse staffing' and 'organizational support and management of hospital' were the same with results from previous studies. In addition, two subfactors, 'participation of decision-making processes' and 'education for improving quality of care', which were similar with results from previous Korean studies, were newly added by using Korean hospital cases. In contrast to previous Korean studies, a unique subfactor this study found was 'nursing processes'. This research confirmed that the six subfactors were highly correlated with job satisfaction, intention to leave, and quality of health care, which represented a nurse's job outcome. CONCLUSION: KGU-NWI including six subfactors and 26 items is an applicable instrument to investigate nurse work environment in Korean hospital general inpatient unit.

The relationship between depressive symptoms among female workers and job stress and sleep quality.

OBJECTIVE: Recently, workers' mental health has become important focus in the field of occupational health management. Depression is a psychiatric illness with a high prevalence. The association between job stress and depressive symptoms has been demonstrated in many studies. Recently, studies about the association between sleep quality and depressive symptoms have been reported, but there has been no large-scaled study in Korean female workers. Therefore, this study was designed to investigate the relationship between job stress and sleep quality, and depressive symptoms in female workers. METHODS: From Mar 2011 to Aug 2011, 4,833 female workers in the manufacturing, finance, and service fields at 16 workplaces in Yeungnam province participated in this study, conducted in combination with a worksite-based health checkup initiated by the National Health Insurance Service (NHIS). In this study, a questionnaire survey was carried out using the Korean Occupational Stress Scale-Short Form(KOSS-SF), Pittsburgh Sleep Quality Index(PSQI) and Center for Epidemiological Studies-Depression Scale(CES-D). The collected data was entered in the system and analyzed using the PASW (version 18.0) program. A correlation analysis, cross analysis, multivariate logistic regression analysis, and hierarchical multiple regression analysis were conducted. RESULTS: Among the 4,883 subjects, 978 subjects (20.0%) were in the depression group. Job stress(OR=3.58, 95% CI=3.06-4.21) and sleep quality(OR=3.81, 95% CI=3.18-4.56) were strongly associated with depressive symptoms. Hierarchical multiple regression analysis revealed that job stress displayed explanatory powers of 15.6% on depression while sleep quality displayed explanatory powers of 16.2%, showing that job stress and sleep quality had a closer relationship with depressive symptoms, compared to the other factors. The multivariate logistic regression analysis yielded odds ratios between the 7 subscales of job stress and depressive symptoms in the range of 1.30-2.72 and the odds ratio for the lack of reward was the highest(OR=2.72, 95% CI=2.32-3.19). In the partial correlation analysis between each of the 7 subscales of sleep quality (PSQI) and depressive symptoms, the correlation coefficient of subjective sleep quality and daytime dysfunction were 0.352 and 0.362, respectively. CONCLUSION: This study showed that the depressive symptoms of female workers are closely related to their job stress and sleep quality. In particular, the lack of reward and subjective sleep factors are the greatest contributors to depression. In the future, a large-scale study should be performed to augment the current study and to reflect all age groups in a balanced manner. The findings on job stress, sleep, and depression can be utilized as source data to establish standards for mental health management of the ever increasing numbers of female members of the workplace.

Pak1/LIMK1/Cofilin Pathway Contributes to Tumor Migration and Invasion in Human Non-Small Cell Lung Carcinomas and Cell Lines.

Squamous cell carcinoma (SCC) and adenocarcinoma (AC) are the major histological types of non-small cell lung carcinoma (NSCLC). Although both SCCs and ACs have been characterized histologically and clinically, the precise mechanisms underlying their migration and invasion are not yet known. Here, we address the involvement in NSCLC of the p21-associated kinase1 (Pak1)/LIM kinase1 (LIMK1)/cofilin pathway, which recently has been reported to play a critical role in tumor migration and invasion. The Pak1/LIMK1/cofilin pathway was evaluated in tumors from SCC (n=35) and AC (n=35) patients and in SCC- and AC-type cell lines by western blotting, immunohistochemistry, and in vitro migration and invasion assays. The levels of phosphorylated Pak1, LIMK1, and cofilin in lung tumor tissues from SCC patients were increased as compared to normal tissues. In addition, immunohistochemistry showed greater expression of phosphorylated cofilin in SCC tissues. Expression of phosphorylated Pak1 and LIMK1 proteins was also significantly higher in SCC-type cells than in AC-type cells. Moreover, migration and invasion assays revealed that a higher percentage of SCC type cells exhibited migration and invasion compared to AC type cells. Migration was also decreased in LIMK1 knockdown SK-MES-1 cells. These findings suggest that the activation of the Pak1/LIMK1/cofilin pathway could preferentially contribute to greater tumor migration and invasion in SCC, relative to that in AC.

Socioeconomic costs of overweight and obesity in Korean adults.

This study was conducted to estimate the socioeconomic costs of overweight and obesity in a sample of Korean adults aged 20 yr and older in 2005. The socioeconomic costs of overweight and obesity include direct costs (inpatient care, outpatient care and medication) and indirect costs (loss of productivity due to premature deaths and inpatient care, time costs, traffic costs and nursing fees). Hypertension, diabetes mellitus, dyslipidemia, ischemic heart disease, stroke, colon cancer and osteoarthritis were selected as obesity-related diseases. The population attributable fraction (PAF) of obesity was calculated from national representative data of Korea such as the National Health Insurance Corporation (NHIC) cohort data and the 2005 Korea National Health and Nutrition Examination Survey (KNHANES) data. Direct costs of overweight and obesity were estimated at approximately U$1,081 million equivalent (men: U$497 million, women: U$584 million) and indirect costs were estimated at approximately U$706 million (men: U$527 million, women: U$178 million). The estimated total socioeconomic costs of overweight and obesity were approximately U$1,787 million (men: U$1,081 million, women: U$706 million). These total costs represented about 0.22% of the gross domestic product (GDP) and 3.7% of the national health care expenditures in 2005. We found the socioeconomic costs of overweight and obesity in Korean adults aged 20 yr and older are substantial. In order to control the socioeconomic burden attributable to overweight and obesity, effective national strategies for prevention and management of obesity should be established and implemented.

Inequalities in medical care utilization by South Korean cancer patients according to income: a retrospective cohort study.

This study explores income inequalities in the utilization of medical care by cancer patients in South Korea, according to type of medical facilities and survival duration. The five-year retrospective cohort study used data drawn from the Korean Cancer Registry, the National Health Insurance database, and the death database of the Korean National Statistical Office. The sample consisted of 43,433 patients diagnosed with cancer in 1999. The authors found significant quantitative inequalities as a function of income in the patients' utilization of medical care. Cancer patients from the highest income class used inpatient and outpatient care more frequently than did patients from the lowest income class. Those with higher incomes tended to use more inpatient and outpatient services at major tertiary hospitals, which were known as providing better medical care than other types of hospitals and clinics. Moreover, horizontal inequality in cancer-care expenditures favoring those with higher incomes was observed during earlier periods of treatment. In conclusion, income substantially affects the utilization of inpatient and outpatient services, amount of medical expenditures, and type of medical facilities.

[A review on socioeconomic position indicators in health inequality research].

OBJECTIVES: Socioeconomic position (SEP) refers to the socioeconomic factors that influence which position an individual or group of people will hold within the structure of a society. In this study, we provide a comprehensive review of various indicators of SEP, including education level, occupation-based SEP, income and wealth, area SEP, life-course SEP, and SEP indicators for women, elderly and youth. METHODS AND RESULTS: This report provides a brief theoretical background and discusses the measurement, interpretation issues, advantages and limitations associated with the use of each SEP indicator. We also describe some problems that arise when selecting SEP indicators and highlight the indicators that appear to be appropriate for health inequality research. Some practical information for use in health inequality research in South Korea is also presented. CONCLUSIONS: Investigation into the associations between various SEP indicators and health outcomes can provide a more complete understanding of mechanisms between SEP and health. The relationship between specific SEP indicators and specific health outcomes can vary by country due to the differences in the historical, socioeconomic, and cultural contexts of the SEP indicators.

[The levels of psychosocial stress, job stress and related factors of medical doctors practicing at local clinics].

OBJECTIVES: This study was conducted to investigate the levels of psychosocial stress, job stress and their related factors among medical doctors practicing at local clinics. METHODS: A survey using a self administered questionnaire was administered to 1,456 doctors practicing at private clinics via post for 2 months (2006. 1 - 2006. 3). Psychosocial stress, job stress,demographic factors, job related factors and health related behaviors were investigated. Among the eligible study population, the respondents were 428 doctors (29.4%). RESULTS: The average scores of psychosocial stress and job stress were 2.19 and 3.13, respectively. The levels of psychosocial stress and job stress were statistically lower in older respondents, those who worked shorter or who were more satisfied with their job, and those with higher socioeconomic status. The level of psychosocial stress was related with smoking status, drinking status and exercise. The level of job stress was related with smoking status and exercise. In multiple linear regression analysis using psychosocial stress as a dependent variable, age, working hours per day, job satisfaction and perception on socioeconomic status were significant independent variables. In analysis using job stress as a dependent variable, age, working hours per day and job satisfaction were significant independent variables. CONCLUSIONS: Stress affects the doctor-patient relationship, productivity and overall health level of people. Therefore, it is important to manage and relieve the stress of doctors. It is suggested that more advanced studies on stress level and related factors and ways to improve the stress and health related behaviors of medical doctors should be conducted.

[Developing the predictive model for the group at high risk for colon cancer].

OBJECTIVES: We developed the predictive model for the incidence of colon cancer by utilizing the health screening data of the National Health Insurance in Korea. We also explored the characteristics of the high risk group for colon cancer. METHODS: The predictive model was used to determine those people who have a high risk for colon cancer within 2 years of their NHI health screening, and we excluded the people who had already been treated for cancer or who were cancer patient. The study population is the insured of the NHI, aged 40 or over and they had undergone health screening from the year 2000 to 2004, according to NHI health screening formula. We performed logistic regression analysis and used SAS Enterprise Miner 4.1. RESULTS: This study shows that there exists a higher rate of colon cancer in males than females. Also, for the population in their 60s, the incidence rate of colon cancer is much higher by 5.36 times than that for those people in their 40s. Amongst the behavioral factors, heavy drinking is the most important determinant of the colon cancer incidence (7.39 times in males and 21.51 times in females). CONCLUSIONS: Our study confirms that the major influencing factors for the incidence of colon cancer are drinking, lack of exercise, a medical history of colon polypus and a family history of colon cancer. As a result, we can choose the group that is at a high risk for colon cancer and provide customized medical information and selective management services according to their characteristics.

[The relationship between regional material deprivation and the standardized mortality ratio of the community residents aged 15-64 in Korea].

OBJECTIVES: This study was performed to investigate the relationship between regional material deprivation and the standardized mortality ratios(SMRs) of community residents aged 15-64 in Korea. METHODS: SMRs were investigated using the registered death data from 1995 to 2000 that was obtained from the Korean National Statistics Office with the denominators being drawn from the 1995 to 2000 census. Material deprivation was measured using the Townsend score that was calculated from the 1995 to 2000 census. The relationship between the regional material deprivation and the SMRs of the community residents aged 15-64 was investigated by using ANOVA, Spearman's rank correlation analysis and Pearson's correlation analysis. The trends in mortality inequality were investigated using the concentration index. RESULTS: On the ANOVA, the SMRs of the men and women residents in the least deprived areas were the smallest and those in the most deprived areas were the largest. Spearman's rank correlation analysis, Pearson's correlation analysis and the concentration index revealed that significant positive relationships exist between the regional material deprivation and the SMRs of the community residents aged 15-64. CONCLUSIONS: This study suggests that there are mortality inequalities among the communities in Korea and part of this difference is due to the material deprivation of the community. Strategies aimed at reducing mortality inequalities among the communities will be needed to address economic inequalities. Further studies are needed to explore the mechanisms of how the regional deprivation influences on health and how the other factors of the community influence on the health of the community residents.

Comparison of disability duration of lumbar intervertebral disc disorders among types of insurance in Korea.

The incidence of work-related musculoskeletal disorder including low back pain sharply increased since 2000 in Korea. The objectives of the present study are to compare disability duration of lumbar intervertebral disc displacement among types of insurances, and to obtain its appropriate duration. The medical records of all patients whose final diagnosis in discharge summary of chart was lumber specified intervertebral disc displacement (LIVD) in 6 large general hospitals in Korea were reviewed to compare the length of admission and disability among different types of insurances. The information on age, gender, the length of admission, the length of follow-up for LIVD, occupation, operation, combined musculoskeletal diseases, and type of insurance was investigated. 552 cases were selected and analyzed to calculate arithmetic mean, median, mode, and geometric mean of disability duration. There was a significant difference in the length of admission and disability among types of insurance after controlling covariates such as age and combined diseases by the analysis of covariance. The length of admission in cases of IACI and AI was much longer than that of HI, and the length of disability in cases of IACI was much longer than that of HI. Prolonged duration of admission and disability was not assumed due to combined diseases, complication or other unexplainable personal factors in cases of those with industrial accidents compensation insurance and automobile insurance. This means that proper management of evidence-based disability duration guidelines is urgently needed in Korea.

Prevalence of metabolic syndrome and waist circumference estimation in some korean adults.

OBJECTIVE: The purpose of this study was to estimate the prevalence of metabolic syndrome, as defined by the ATP III report, in some Korean adults and use the Asian-Pacific proposed waist circumference to investigate waist circumference in some Korean adults using ROC curves. METHODS: Study subjects were seventy-five thousands and ninety one persons (47, 979 men and 27, 111 women) who were selected among the patients who visited hospital for health evaluation from January 2000 to December 2001. All subjects were measured by height, weight, waist and hip circumferences, blood pressure and blood chemistry (lipid profile). RESULTS: The mean age was 41.6+/-8.5 years in men, 41.1+/-10.4 years in women (p< 0.05). Body mass index was in the normal range in 35.3% of men, and 55.9% of women. In both men and women, blood pressure, blood sugar, total cholesterol and triglyceride were positively correlated with BMI. waist circumference, and Broca's index (p< 0.01). However HDL. choloesterol was correlated negatively (p< 0.01). Using ROC curve, the calculated waist circumferences were 84 cm in men (sensitivity 61.4% and specificity 64.1%) and 74 cm in women (sensitivity 65.0% and specificity 73.2%). The age adjusted prevalences of the metabolic syndrome as defined by NCEP ATP III were different for men (6.4%) and women (14.6%). The prevalence increased from 1.2% among participants aged 20 through 29years to 15.0% among participants aged over 60years in men (p< 0.05) and from 1.6% to 27.4% respectively, in women. The age adjusted prevalences, as defined by using the waist circumference that was recommended by WHO's regional office for the western Pacific, were 10.6% in men and 18.5% in women. The age adjusted prevalences, as defined by using the waist circumference that was calculated by the ROC curves, were 17.1% in men and 22.4% in women. And All prevalences were increased following increased BMI and Broca's index. CONCLUSIONS: The prevalence of metabolic syndrome in some Korean adults was lower than that in western adults. Nevertheless because waist circumference was differed among race and region, application of the same criteria was not proper. Morcover, a higher awareness was required in women, because the prevalence of metabolic syndrome was rapidly increased with increment of age.