Impact of continuity of care on older adults diagnosed with mental and behavioural disorders at risk of death due to intentional self-harm: a retrospective Korean cohort study.

OBJECTIVES: The aim of this study was to evaluate the impact of continuity of care on older adults diagnosed with mental and behavioural disorders who are at risk of death due to intentional self-harm. STUDY DESIGN: This was a retrospective cohort study. METHODS: Data from the Korean National Health Insurance Service-Elderly Cohort Database (2002-2013) were used. A total of 53,980 patients who had visited the outpatient clinic three or more times within the year following the initial diagnosis of mental and behavioural disorders were included. A generalised estimating equation model was generated to examine the impact of continuity of care (CoC) on the risk of death due to intentional self-harm among older adults with mental illnesses. RESULTS: The risk of death due to intentional self-harm was significantly higher in those with poor CoC for mental and behavioural disorders than in those with good CoC. The risk ratio, adjusting for all covariates, was larger for the Usual Provider of Care index (adjusted risk ratio [aRR]: 1.63, 95% confidence interval [CI]: 1.25-2.12) than for the CoC index (aRR: 1.50, 95% CI: 1.18-1.90), indicating a stronger association with the concentration of contact with the most frequently visited provider. CONCLUSIONS: Poor CoC among Korean older adults diagnosed with mental and behavioural disorders was identified as a significant risk factor for death due to intentional self-harm. The results of this study highlight the need for interventions that can prevent suicidal behaviour in older adults, such as institutionalising the usual providers of mental health care for older adults.

Association of exposure to secondhand smoke at home with early age at menarche in South Korea.

OBJECTIVES: The secular trend in age at menarche (AAM) has declined both worldwide and in Korea. Early AAM is associated with the risk of several diseases, reproductive capacity, and psychological problems. We aimed to investigate the relationship between secondhand smoke (SHS) exposure at home and early puberty onset using AAM in Korean adolescents. STUDY DESIGN: This is a retrospective cross-sectional study. METHODS: This study used data from the Korea Youth Risk Behavior Web-based Survey 2014-2015. We used the mean AAM (12.2 years) as a determinant of early AAM. After the exclusion of girls without menarche or who did not respond, the total population comprised 63,618 participants. We categorized AAM as 'early' and 'average or late.' Adolescents with SHS exposure were assigned to the 'never exposed,' 'light exposure,' and 'heavy exposure' groups. Multiple logistic regression analyses were performed. RESULTS: We observed a positive association, approximately 1.12 times, between early AAM and high SHS exposure (odds ratio [OR], 1.12; 95% confidence interval [CI], 1.05-1.19). Girls who started smoking before the age of 12 years (OR, 1.68; 95% CI, 1.41-1.99) showed a stronger association with early AAM than non-smokers. Active smoking showed a stronger association with early AAM. Never smokers with high SHS exposure at home were 1.13 times likelier to have an early AAM (OR, 1.13; 95% CI, 1.05-1.22) than those without SHS exposure. CONCLUSIONS: In addition to active smoking, SHS may also be a risk factor for early AAM. Education aimed at active and secondhand smoking prevention is needed to protect children against early AAM.

Do severe maternal morbidity and adequate prenatal care affect the delivery cost? A nationwide cohort study for 11 years with follow up.

OBJECTIVE: To explore whether severe maternal morbidity (SMM) and adequate prenatal care (PNC) affect delivery cost. DESIGN: Population-based retrospective cohort study. SETTING: National Health Insurance Service National Sample Cohort in Korea. POPULATION: A total of 90 035 deliveries in 2003 and 2013. METHODS: Severe maternal morbidity was determined using the Centers for Disease Control and Prevention's algorithm. Delivery medical costs were calculated by estimating claimed total medical costs using year-specific inflation adjustment factors. Adequate PNC was estimated by the Kessner Adequacy of Prenatal Care Index. To estimate adjusted mean delivery medical costs related to SMM, we applied a generalised estimating equation model with log link and γ distribution, by adjusting for all covariates. MAIN OUTCOME MEASURES: Delivery cost was calculated by estimating claimed total medical cost during delivery hospitalisation using year-specific inflation. RESULTS: Of the 90 035 deliveries, 2041 (2.27%) involved SMM. Women with SMM had a greater adjusted mean cost of delivery (US$ 1,263, 95% CI US$ 1,196-1,334) than those without (US$ 740, 95% CI US$ 729-750). Interestingly, women who had inadequate PNC had higher delivery medical costs than those with adequate PNC, adjusted for all covariates. CONCLUSION: Delivery involving SMM was associated with nearly doubled medical costs. Additionally, inadequate PNC increased the medical costs of delivery. The current study confirmed the burden of SMM and found that adequate PNC might be a useful preventive factor in reducing medical costs. TWEETABLE ABSTRACT: We found that women with severe maternal morbidity and inadequate prenatal care had increased medical costs during delivery hospitalisation.

Toward safer prescribing: evaluation of a prospective drug utilization review system on inappropriate prescriptions, prescribing patterns, and adverse drug events and related health expenditure in South Korea.

OBJECTIVES: This study aimed to evaluate the effect of the prospective drug utilization review (DUR) system introduced in Korea in December 2010 as a real-time method to improve patient safety, in terms of changes in prescribing practices, adverse drug events (ADEs), and ADE-related healthcare expenditure, using non-steroidal anti-inflammatory drugs (NSAIDs) and their common ADEs as a guide. STUDY DESIGN: We used an interrupted time-series study design using generalized estimating equations to evaluate changes in prescription rate and ADE-related healthcare expenditure. Cox regression analysis was used to evaluate the probability of NSAID-associated ADEs. METHODS: A total of 154,585 outpatients with musculoskeletal or connective tissue disorders, without pre-existing gastric bleeding or ulcers were included in this study. The primary outcome was the level and trend change in prescription rate, drug-drug interactions, coprescribed gastro-protective drugs, and defined daily dose (DDD) of NSAIDs. The secondary outcome was the probability of ADEs and changes in ADE-related healthcare expenditure. RESULTS: There was a significant trend change after introducing the DUR system in terms of drug-drug interactions (-3.6%) and coprescribed gastro-protective drugs (+0.6%). The mean DDD of NSAIDs increased by 0.2. The probability of ADEs decreased overall (-1.7%) and in the high-risk group (age ≥65 years; -9.6%); however, only the latter was significant. There was no significant trend or level change in ADE-related health expenditure. CONCLUSIONS: The introduction of the DUR system was associated with more efficient prescribing, including a reduction in drug-drug interactions and an increase in the use of gastro-protective drugs. The system had a positive effect on patient outcome but was not associated with reduced ADE-related costs. Further studies are needed to evaluate the long-term effects of the DUR system in Korea.

Temporary work and depressive symptoms in South Korean workers.

BACKGROUND: In many countries, including South Korea, labour market changes have led to an increase in unstable, temporary jobs. There is evidence that workers in such jobs may experience poorer mental health than those in more stable employment. AIMS: To investigate the association between temporary employment and depressive symptoms in South Korean workers. METHODS: We analysed data from the 2010-2014 Korean Welfare Panel Study (KOWEPS). Employment type was categorized into workers paid per day of labour (day labourers), those on short-term contracts (fixed-term workers) and permanent workers. The association between employment type and depressive symptoms, measured using the Center for Epidemiological Studies Depression scale (CES-D 11), was examined using the generalized estimating equation model. RESULTS: A total of 3756 workers aged 20-59 were included in the 2010 baseline population. Day labourers had the highest mean CES-D 11 score, followed by fixed-term workers and permanent workers. With the day labourer group as reference, fixed-term workers (ß: -1.5027, P < 0.001) and permanent workers (ß: -2.1848, P < 0.001) showed statistically significant decreases in depression scores. CONCLUSIONS: Compared with day labourers, fixed-term workers and permanent workers had progressively lower depression scores. The findings of this study suggest that mental health inequalities based on employment type exist in South Korea.

The association between perceived unmet medical need and mental health among the Republic of Korea Armed Forces.

INTRODUCTION: We investigated the effect of unmet medical need on the mental health of Republic of Korea (ROK) Armed Forces personnel, as most of the service members work in remote areas and often experience such unmet needs. METHODS: This study used secondary data from the 2014 Military Health Survey (MHS), conducted by the ROK School of Military Medicine and designed to collect military health determinants. Descriptive statistics showed the general characteristics of the study populations by variable. We specifically compared the population after stratifying participants by suicide ideation. An analysis of variance was also carried out to compare Kessler Psychological Distress Scale 10 Scores. Additionally, dependent spouses and children of both active-duty service members and retirees are included among those entitled to Military Health System healthcare. RESULTS: Among the 4967 military personnel, 681 (13.7%) individuals reported an experience of unmet medical need within the past 12 months and gave reasons of 'no time (5.15%)', 'long office wait (2.6%)', 'no money (0.22%)', 'long distance from base (1.19%)', 'illness but not very serious (1.65%)', 'mistrust in doctors (1.95%)' and 'pressure due to performance appraisal (0.95%)'. Regression analysis revealed that unmet medical need was significantly associated with negative mental health (ß=1.753, p<0.0001) and increased suicide ideation (OR=2.649, 95% CI 1.84 to 3.82). Also, soldiers reporting unmet medical need due to 'no money', 'no time' or 'pressure due to performance appraisal' were significantly more likely to experience similar negative mental health effects. CONCLUSIONS: Our study indicates that unmet medical need is significantly associated with soldiers' mental health decline and suicide ideation, highlighting the importance of providing military personnel with timely, affordable and sufficient medical care.

The influence of sexual harassment on mental health among female military personnel of the Republic of Korea Armed Forces.

INTRODUCTION: Reports of sexual harassment are becoming more frequent in Republic of Korea (ROK) Armed Forces. This study aimed to analyse the impact of sexual harassment on mental health among female military personnel of the ROK Armed Forces. METHODS: Data from the 2014 Military Health Survey were used. Instances of sexual harassment were recorded as 'yes' or 'no'. Analysis of variance (ANOVA) was carried out to compare Kessler Psychological Distress Scale 10 (K-10) scores. Multiple logistic regression analysis was performed to identify associations between sexual harassment and K-10 scores. RESULTS: Among 228 female military personnel, 13 (5.7%) individuals experienced sexual harassment. Multiple logistic regression analysis revealed that sexual harassment had a significantly negative impact on K-10 scores (3.486, p<0.04). Higher K-10 scores among individuals experiencing sexual harassment were identified in the unmarried (including never-married) group (6.761, p<0.04), the short-term military service group (12.014, p<0.03) and the group whose length of service was <2 years (11.067, p<0.02). CONCLUSIONS: Sexual harassment has a negative impact on mental health. Factors associated with worse mental health scores included service classification and length of service. The results provide helpful information with which to develop measures for minimising the negative psychological effects from sexual harassment and promoting sexual harassment prevention policy.

Combined effect of individual and neighborhood socioeconomic status on mortality in patients with newly diagnosed dyslipidemia: A nationwide Korean cohort study from 2002 to 2013.

BACKGROUND AND AIM: The study aims to determine whether dyslipidemia patients living in less affluent neighborhood are at a higher risk of mortality compared to those living in more affluent neighborhoods. METHODS AND RESULTS: A population-based cohort study was conducted using a stratified representative sampling from the National Health Insurance claim data from 2002 to 2013. The target subjects comprise patients newly diagnosed with dyslipidemia receiving medication. We performed a survival analysis using the Cox proportional hazard model. Of 11,946 patients with dyslipidemia, 1053 (8.8%) subjects died during the follow-up period. Of the dyslipidemia patients earning a middle-class income, the adjusted HR in less affluent neighborhoods was higher than that in the more affluent neighborhoods compared to the reference category of high individual SES in more affluent neighborhoods (less affluent; hazard ratio (HR) = 1.64, 95% confidence interval (CI): 1.35-1.99 vs. more affluent; HR = 1.48, 95% CI: 1.20-1.81, respectively). We obtained consistent results in patients with lower income, wherein the adjusted HR in less affluent neighborhoods was higher than that in more affluent neighborhoods (less affluent; HR = 1.52, 95% CI: 1.16-1.97 vs. more affluent; HR = 1.41, 95% CI: 1.04-1.92, respectively). CONCLUSION: Living in a less affluent neighborhood contributes to higher mortality among dyslipidemia patients. The individual- and neighborhood-level variables cumulatively affect individuals such that the most at-risk individuals include those having both individual- and neighborhood-level risk factors. These findings raise important clinical and public health concerns and indicate that neighborhood SES approaches should be essentially considered in health-care policies similar to individual SES.

Effect of endoscopy screening on stage at gastric cancer diagnosis: results of the National Cancer Screening Programme in Korea.

BACKGROUND: Although gastric cancer screening is common among countries with a high prevalence of gastric cancer, there is little data to support the effectiveness of this screening. This study was designed to determine the differences in stage at diagnosis of gastric cancer according to the screening history and screening method (upper gastrointestinal series (UGIS) vs endoscopy). METHODS: The study population was derived from the National Cancer Screening Programme (NCSP), a nationwide organised screening programme in Korea. The study cohort consisted of 19 168 gastric cancer patients who had been diagnosed in 2007 and who were invited to undergo gastric cancer screening via the NCSP between 2002 and 2007. RESULTS: Compared with never-screened patients, the odds ratios for being diagnosed with localised gastric cancer in endoscopy-screened patients and UGIS-screened patients were 2.10 (95% CI=1.90-2.33) and 1.24 (95% CI=1.13-1.36), respectively. CONCLUSIONS: Screening by endoscopy was more strongly associated with a diagnosis of localised stage gastric cancer compared with screening by UGIS.

Association between obsessive-compulsive disorder and the risk of schizophrenia using the Korean National Health Insurance Service-National Sample Cohort: a retrospective cohort study.

AIMS: Obsessive-compulsive disorder (OCD) and schizophrenia are often reported as co-morbid conditions. However, the evidence of an association between OCD and the risk of schizophrenia is limited. This study investigated the risk of schizophrenia in patients newly diagnosed with OCD using a nationally representative sample cohort in South Korea. METHODS: Data were obtained from the 2002-2013 Korean National Health Insurance Service-National Sample Cohort of the National Health Insurance Service. Using propensity score matching, 2509 patients with OCD and a control group of 7527 patients were included in the analysis. Chi-squared tests were used to investigate and compare the general characteristics of the study population. The risk of schizophrenia was analysed using the Cox proportional hazard model. RESULTS: The incidence rate was 45.79/10 000 person-year for patients with OCD and 4.19/10 000 person-year for patients without OCD. Patients with OCD had a higher risk of schizophrenia compared to the control group after adjusting for covariates (hazard ratio = 10.46, 95% confidence interval = 6.07-18.00). CONCLUSIONS: This study identified an association between the diagnosis of OCD and the risk of schizophrenia in a South Korean national representative cohort. Further research using a prospective design to clarify the causality of OCD in schizophrenia in a controlled environment should be conducted to validate these findings.

Factors associated with the intention to have colorectal cancer screening in Korean adults.

The purpose of this study was to investigate the factors related to screening intention in a population-based screening programme for colorectal cancer. The data were taken from the 2008 Korean National Cancer Screening Survey. We conducted a nationwide survey with trained interviewers using a questionnaire. A total of 2038 participants agreed to answer the survey. There were 955 study subjects aged ≥ 50 years in the target age group for colorectal cancer screening. Colorectal cancer screening behaviour and demographic characteristics were collected to evaluate intention for colorectal cancer screening and related factors. Descriptive statistics and multiple logistic regression were used in the analysis. The lifetime screening rate was 50.4% (50.9% for men and 49.8% for women). The screening rate with recommendation was 39.7% (39.3% for men and 40.1% of women). The odds ratios of intention to be screened increased significantly in younger subjects and those screened with double-contrast barium enema or colonoscopy. 'Without any symptoms' was reported as the most frequent reason for non-attendance or no intention to be screened. Age and recent screening methods were important factors related to intention to be screened for colorectal cancer. Further research is needed to identify remaining barriers to screening.

Satisfaction with mammography in the National Cancer Screening Programme participants of age 40s in Korea.

The aim of this study was to evaluate satisfaction with the National Cancer Screening Programme of mammography in Korea and to examine the association between subscales of satisfaction and general satisfaction. We conducted a cross-sectional telephone survey for women who had obtained a National Cancer Screening Programme mammographic screening at general hospitals between May and October 2008. The present study included 2005 women in their forties. We performed multivariate linear regression using dependent variable as general satisfaction and independent variables as subscales of satisfaction, such as pre-screening information transfer, staff interpersonal skills, physical surroundings and results reporting. Participants were stratified according to the result of their mammogram as negative or positive. Mean score of satisfaction was above 2.5 of 4 for all subscales. Women who received positive results were less satisfied with all of subscale factors. Staff interpersonal skills were the most important factor that contributed to general satisfaction. Future efforts such as staff training programme of communication/attitude skills, ensuring privacy and explanation of possible discomfort of the screening would be needed.

Support from superiors reduces depression in Republic of Korea military officers.

BACKGROUND: The prevalence of depression is relatively high in the Korean military. Social support is a protective factor against depression and is classified into four categories: emotional support-having the sense of feeling loved; instrumental support-receiving material assistance; informational support-receiving advice; appraisal support-feeling valued and respected for one's abilities. OBJECTIVE: To investigate the effect of support from one's superior on depression among Republic of Korea (ROK) military officers. METHODS: 2047 participants from the 2015 Military Health Survey were included in the study. The Korean version of the Beck Depression Inventory was used to measure depression, and a self-reported questionnaire was used to assess support from one's superior. A chi-squared test and multiple logistic regression were used to analyse the data. RESULTS: Of the 2047 participants, 177 (8.6%) had depression. Military officers who did not receive support from their superior were more likely to have depression than than those who did receive support (OR=2.09, 95% CI 1.30 to 3.36). Additionally, military personnel who did not receive emotional or appraisal support were more likely to have depression (emotional support: OR=2.37, 95% CI 1.31 to 4.29; appraisal support: OR=1.56, 95% CI 1.48 to 2.75). CONCLUSIONS: Our study found that depression in military officers was associated with lack of support from superiors. In particular, emotional support and appraisal support had a statistically significant effect. Therefore, we suggest that the ROK armed forces consider early intervention and management for high-risk groups. A social support programme and organisational atmosphere are also needed to improve supportive ability and skills of superiors.

Associations between earplug use and hearing loss in ROK military personnel.

INTRODUCTION: The easiest way to prevent noise-induced hearing loss (NIHL) is to wear earplugs. The Republic of Korea (ROK) Ministry of National Defense (MND) is supplying earplugs to prevent NIHL, but many patients still suffer from this. We speculated that earplugs would have a high NIHL rate, depending on the rate of use of earplugs, regardless of the rate of supply. Therefore, we conducted this study to investigate the relationship between the use of earplugs and hearing loss by ROK military personnel. METHODS: The study used data from the Military Health Survey conducted in 2014-2015, which included 13 470 questionnaires completed by ROK military personnel. Hearing loss and earplug use were self-reported. Logistic regression analysis was used to assess associations between earplug use and hearing loss. RESULTS: The study sample included 13 470 ROK military personnel (response rate of 71.2%) (Army, 8330 (61.8%); Navy/Marines, 2236 (16.6%); and Air Force, 2904 (21.6%)). Overall, 18.8% of Korean military personnel reported that they always wore earplugs, and 2.8% reported hearing loss. In logistic regression analysis, there were significant differences in the rates of hearing loss associated with wearing earplugs sometimes (OR=1.48, 95% CI 1.07 to 2.05) and never wearing earplugs (OR=1.53, 95% CI 1.12 to 2.10). In subgroup analysis, in Air Force, non-combat branch, forward area and long-term military service personnel increased hearing loss was associated with not wearing earplugs. CONCLUSION: Our study confirmed that within the ROK military, there is an association between hearing loss and lack of earplug use. In the ROK MND, Army, Navy/Marines and Air Force headquarters must provide guidelines for the use of earplugs during field training to protect military personnel's hearings and, if necessary, need to be regulated or institutionalised.

Accident prevention activity and accident experience in the Republic of Korea military.

INTRODUCTION: According to data released by the Korea National Statistical Office, the number of accidents has been decreasing since 2012. However, a considerable number of deaths related to safety accidents (23-46 deaths) are still reported annually. This study aimed to observe the correlation between accident prevention activities in the Republic of Korea (ROK) military and the incidence of safety accidents. METHODS: The study used data from the 2014-2015 Military Health Survey and included 13 618 responses (Army: 8414 (61.8%); Navy/Marine: 2262 (16.6%); Air Force: 2942 (21.6%)) from the ROK military personnel. Accident experiences and thoughts on accident prevention activities were self-reported. Multiple logistic regression analysis was used to examine the validity of accident prevention activity and accident experience. RESULTS: Of the 13 618 military personnel who responded, 12.0% reported experiencing safety accidents in the military and 1020 (7.5%) felt that accident prevention activities in the military were insufficient. On logistic regression analysis, we found a significant difference (insufficiency OR=1.56, CI 1.31 to 1.86). In particular, military personnel who belong to the Army and Navy were more likely to think that accident prevention activities were insufficient. In addition, military personnel who experienced falls/slips, crash, and laceration/puncture wound/amputation/penetrating wound accidents were more likely to think accident prevention activities were insufficient. CONCLUSIONS: Our study found that accident prevention activities in the military and accident experiences were related. It is necessary for the ROK Ministry of Defense, Army, Navy and Air Force headquarters to re-evaluate their accident prevention systems.

Combined effect of socioeconomic status, viral hepatitis, and lifestyles on hepatocelluar carcinoma risk in Korea.

BACKGROUND: The independent and combined effects of socioeconomic status (SES), viral hepatitis, and other lifestyle factors on hepatocellular carcinoma (HCC) risk have not been investigated among Koreans. METHODS: From the National Cancer Center Hospital, 207 HCC cases and 828 age- and gender-matched controls aged 30 years or older were recruited. Socio-demographic and behavioural risk factors were ascertained through personal interview, and infection with hepatitis B and C viruses was determined by their serologic markers. Multivariate logistic regression and synergy index methods were applied for statistical analysis. RESULTS: HB surface antigen (HbsAg) and anti-HCV-positive rates were 149.3 and 185.1 times higher in cases than controls, respectively. Lifetime alcohol consumption (odds ratio: 2.96, 95% CI: 1.29-6.79), cigarette smoking (OR: 3.53, 95% CI: 1.31-9.52), and family income (OR: 17.07, 95% CI: 4.27-68.25) were independently associated with the risk of HCC in subjects with or without viral hepatitis. Synergistic interaction on HCC risk was observed between low income and HBsAg positivity (SI: 3.12, 95% CI: 1.51-6.47) and between low income and heavy alcohol intake (SI: 2.93, 95% CI: 1.24-6.89). CONCLUSION: The inverse association with SES suggests SES as an independent and synergistic predictor of HCC. Heavy alcohol intake also showed a combined effect with low SES on HCC risk.

Effect of Sedentary Time on the Risk of Orthopaedic Problems in People Aged 50 Years and Older.

OBJECTIVE: Many people experience orthopaedic problems (OPPs), such as knee joint pain, hip joint pain, low back pain, and knee stiffness in their lifetimes. OPPs can impair lower extremity function, cause depression, and worsen quality of life. The aim of this study was to investigate the association between sedentary time (SDT) and OPPs. DESIGN: Retrospective cross-sectional study. SETTING: This study used data from the 2014-2015 Korea National Health and Nutrition Examination Survey. Survey participants with previous or current osteoarthritis or rheumatoid arthritis, as diagnosed by a doctor, were excluded. OPPs were defined as knee joint pain, hip joint pain, low back pain, and knee stiffness. The cut-off value for SDT was 7.5 hours/day. The study population comprised 3,671 people (1,856 men and 1,815 women), all of whom were ≥50 years-old. Multiple logistic regression analyses were performed. RESULTS: A total of 328 men (17.7%) and 519 women (28.6%) had OPPs. Men with SDTs ≥7.5 hours had a greater risk of OPPs than did men with SDTs <7.5 hours (odds ratio [OR], 1.45; 95% confidence interval [CI], 1.08-1.93). A pink-collar job, physical inactivity during leisure time, and passive (e.g. riding in a car or train) versus active (e.g. walking or riding a bicycle) transportation predicted OPPs in men with SDTs ≥7.5 hours. SDT was a risk factor for knee joint pain in men (OR, 1.80; 95% CI, 1.11-2.92) and hip joint pain in women (OR, 2.05; 95% CI, 1.35-3.11). CONCLUSIONS: In men, prolonged SDT is a risk factor for OPPs. More physical activity programmes should be launched at the community level for people ≥50 years-old to reduce the occurrence of OPPs.

Effects of self-reported hearing or vision impairment on depressive symptoms: a population-based longitudinal study.

AIMS: The aims of this study were to investigate the effects of either hearing, vision or dual sensory impairment on depressive symptoms and to identify subgroups that are vulnerable and significantly affected. METHODS: Data from the 2006-2014 Korean Longitudinal Study of Aging (KLoSA) were used and a total of 5832 individuals were included in this study. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression (CES-D10) scale. Sensory impairment was assessed according to the levels of self-reported hearing or vision, which were categorised as either good (excellent, very good or good) or poor (fair or poor). The changes in hearing or vision from records of previous survey were investigated. Changes from good to poor, which indicates new onset, were defined as hearing impairment or vision impairment. Interactions of changes in hearing and vision were considered in the analysis. Dual sensory impairment was indicated when hearing impairment and vision impairment both developed at the same time. Demographic, socioeconomic and health-related factors were considered as potential confounders and were adjusted for in the generalised estimating equation model. RESULTS: Individuals with hearing impairment demonstrated significantly more severe depressive symptoms [ß = 0.434, standard errors (s.e.) = 0.097, p < 0.001] than those who had good hearing. Those with vision impairment also showed significantly elevated depressive symptoms (ß = 0.253, s.e. = 0.058, p < 0.001) than those with good vision. When the interactions between hearing and vision were considered, participants with dual sensory impairment showed significantly more severe depressive symptoms (ß = 0.768, s.e. = 0.197, p < 0.001) than those with good hearing and vision. The effect of a single and dual sensory impairment on depressive symptoms was significant in both sexes and across age groups, except for vision impairment in male participants. CONCLUSIONS: Hearing, vision and dual sensory impairment are significantly associated with depressive symptoms. Our results suggest that treatment or rehabilitation of either hearing or vision impairment would help prevent depression.

The economic burden of cancer in Korea in 2002.

Cancer is the leading cause of death and one of the most significant healthcare expenses in Korea. The purpose of this study was to estimate the economic burden of cancer on Korean society. We studied the medical, non-medical, morbidity and mortality costs related to cancer treatment, lost productivity and premature death. Healthcare claims for 2002 obtained from the Health Insurance Review Agency were used to estimate medical expenditures; these were linked with the Korean Central Cancer Registry database to identify cancer patients. The number of deaths used to estimate mortality costs was obtained from the Annual Report of Mortality from the National Statistics Office of Korea. Moreover, data from the Korean National Statistics Office and Ministry of Labor were used to calculate life expectancy at the age of death, labour force participation, and average age- and gender-specific earnings. In 2002, the estimated total economic cost of cancer amounted to $9.4 billion (1.72% of GDP) at a 3% discount rate. Medical care costs amounted to 13.7% of total costs, non-medical costs 6.5%, morbidity costs 14.5%, and mortality costs accounted for 65.3%. Increased prevention, earlier diagnosis, new therapies and effective cancer control policies are needed to reduce the economic burden of cancer in Korea.

Codon usage limitation in the expression of HIV-1 envelope glycoprotein.

BACKGROUND: The expression of both the env and gag gene products of human immunodeficiency virus type 1 (HIV-1) is known to be limited by cis elements in the viral RNA that impede egress from the nucleus and reduce the efficiency of translation. Identifying these elements has proven difficult, as they appear to be disseminated throughout the viral genome. RESULTS: Here, we report that selective codon usage appears to account for a substantial fraction of the inefficiency of viral protein synthesis, independent of any effect on improved nuclear export. The codon usage effect is not specific to transcripts of HIV-1 origin. Re-engineering the coding sequence of a model protein (Thy-1) with the most prevalent HIV-1 codons significantly impairs Thy-1 expression, whereas altering the coding sequence of the jellyfish green fluorescent protein gene to conform to the favored codons of highly expressed human proteins results in a substantial increase in expression efficiency. CONCLUSIONS: Codon-usage effects are a major impediment to the efficient expression of HIV-1 genes. Although mammalian genes do not show as profound a bias as do Escherichia coli genes, other proteins that are poorly expressed in mammalian cells can benefit from codon re-engineering.