Individual-level Associations Between Indicators of Social Capital and Alcohol Use Disorders Identification Test Scores in Communities With High Mortality in Korea.

OBJECTIVES: This study examined associations among social capital indicators (social participation and generalized trust) at the individual level and alcohol use, which was quantified using Alcohol Use Disorders Identification Test (AUDIT) scores. METHODS: In total, there were 8800 participants in community health interviews, including 220 adults sampled systematically from a resident registration database of each of 40 sub-municipal administrative units of local (city or county) governments. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated using polychotomous logistic regression. RESULTS: The aORs for abstainers versus people with AUDIT scores of 0-7, based on 3 questions on generalized trust, in comparison to those with no positive responses, were 1.15 (95% CI, 0.99 to 1.34) for 1 positive response, 1.16 (95% CI, 0.98 to 1.37) for 2 positive responses; and 1.39 (95% CI, 1.20 to 1.61) for 3 positive responses. The aORs for abstainers versus people with AUDIT scores of 0-7, in comparison to participation in no organizations, were 0.61 (95% CI, 0.54 to 0.69) for participation only in informal organizations; 2.16 (95% CI, 1.57 to 2.99) for participation only in religious organizations; 2.41 (95% CI, 1.10 to 5.29) for participation only in volunteer organizations; and 0.65 (95% CI, 0.57 to 0.74) for participation in formal organizations. Participants in formal social organizations, regardless of their participation in informal organizations, were more likely to have AUDIT scores of 8-15 (aOR, 1.29; 95% CI, 1.04 to 1.60) or ≥16 (aOR, 1.65; 95% CI, 1.22 to 2.23) than to have scores of 0-7. CONCLUSIONS: Our findings may have implications for health policy to reduce alcohol problems.

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.

Self-esteem as a Moderator of the Effects of Happiness, Depression, and Hostility on Suicidality Among Early Adolescents in Korea.

OBJECTIVES: The purpose of this study was to investigate the role of self-esteem as a moderator of the factors influencing suicidality among middle-schoolers. METHODS: Moderated multiple regression analysis was applied to assess the influence of happiness, depression, and hostility on suicidality and to determine the degree to which self-esteem served as a moderator of those relationships. Data were collected from 268 students at a middle school in Busan, Korea, using a self-administered structured questionnaire. RESULTS: Happiness, depression, and hostility had significant direct effects on suicidality. Self-esteem showed no direct effect, but had a significant moderating effect on the relationship between hostility and suicidal behavior. CONCLUSIONS: These results suggest that various interventions, such as counseling programs, should be designed to alleviate hostility and depression and to enhance happiness and self-esteem among early adolescents.

Associations of Generalized Trust and Social Participation at the Individual Level with Unmet Healthcare Needs in Communities with High Mortality.

BACKGROUND: The aim of this study was to investigate whether generalized trust and/or social participation at an individual level have negative associations with unmet healthcare needs. METHODS: Door-to-door interviews were conducted by trained interviewers to collect information. The 8,800 study participants included 220 adults sampled systematically using the resident registration database from 40 sub-municipal-level administrative units in Korea. Unmet healthcare needs were measured subjectively by the following question: "During the past 12 months, was there ever a time when you felt that you needed healthcare (excluding dental care) but did not receive it?" The responses were classified as either "yes" or "no." RESULTS: The adjusted odds ratios (ORs) for unmet healthcare needs based on one positive response, two positive responses, and three positive responses to the three items of generalized trust compared to no positive responses were 0.92 (95% confidence interval [CI], 0.77-1.09), 0.90 (95% CI, 0.74-1.09), and 0.73 (95% CI, 0.61-0.87), respectively. The adjusted ORs for unmet healthcare needs based on social participation only in informal organizations, only in formal organizations, and in both informal and formal organizations compared to no social participation were 0.83 (95% CI, 0.71-0.98), 0.97 (95% CI, 0.77-1.21), and 0.97 (95% CI, 0.82-1.15), respectively. The covariates included in the multiple logistic regression were sociodemographic variables (gender, age, marital status, educational level, occupation, food security, and administrative unit), self-rated health, and perceived stress. CONCLUSION: Therefore, generalized trust and social participation in informal organizations can decrease the incidence of unmet healthcare needs.

Association of social capital at the individual level with physical activity in communities with high mortality in Korea.

The aim of this study was to investigate the association of various dimensions of social capital at the individual level with physical activity. We used data from community health interviews conducted in 40 sub-municipal-level administrative units with high mortality from August to October in 2010, 2011 or 2012 for health projects in South Korea. The 8800 study subjects included 220 adults from each administrative unit, who were sampled systematically using the resident registration database. The physical activity level was defined according to the intensity, duration and frequency of self-reported physical activity. Social capital indicators were assessed with measures used in other health surveys or studies. Adjusting for gender, age, marital status, educational level, occupation, food security (a proxy for socio-economic status), administrative unit and self-rated health, we calculated the adjusted odds ratio (AOR) with a 95% confidence interval (CI) of participating in physical activity based on various measures of social capital using multivariate logistic regression analysis. Social participation in both informal and formal organizations compared with no social participation, higher generalized trust compared with lower trust and higher perceived control at both the community and individual levels compared with lower perceived control at both levels increased the odds of being physically active [AOR = 1.25 (95% CI: 1.10-1.41), 1.36 (95% CI: 1.19-1.54) and 1.31 (95% CI: 1.17-1.48), respectively]. Various social capital measures at the individual level were found to be associated with physical activity independently of each other and of confounders in communities with high mortality in Korea.

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.

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.

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.

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.

[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.

The C677 mutation in methylene tetrahydrofolate reductase gene: correlation with uric acid and cardiovascular risk factors in elderly Korean men.

The C677T mutation in the methylene tetrahydrofolate reductase (MTHFR) gene results in elevated homocysteine levels and, presumably, in increased cardiovascular risk. Moreover, elevated homocysteine levels are reportedly associated with high serum uric acid levels. We evaluated the MTHFR genotype and a panel of biochemical, hematological variables, and lifestyle characteristics in 327 elderly Korean men (age range 40-81 yr; mean, 51.87). This study shows that mutation of the MTHFR gene may be a risk for hyperuricemia. The mean uric acid levels for the C/C, C/T and T/T genotypes were 5.54, 5.91 and 6.33 mg/dL, respectively (p=0.000). The T/T genotype was significantly more frequent in subjects with high uric acid levels (p=0.003). Thus, this mutation of the MTHFR gene is implied by the study results to be a risk factor of hyperuricemia in elderly Korean men. However, the relationship between the MTHFR mutation and uric acid metabolism remains unclear. Therefore, further studies are necessary to explain the associated between the MTHFR mutation and elevated uric acid levels, and to examine potential relationships between it and conventional cardiovascular risk factors.