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It has previously been reported that an individual's body mass index (BMI) contemporaneously penalizes wages for women, but has no effect and sometimes rewards wages for men. In young adults, we estimate the association of BMI status with initial wages to assess whether initial BMI at the beginning of an individual's career affects initial and later earnings. We pooled data from 388 men and 305 women, aged 20-40 years, with BMI information for the first year of employment, using the Korean Labor and Income Panel Study. A labor market penalty for a higher BMI among women was found only for overweight or obese segments, particularly those with relatively higher monthly wages. Meanwhile, a higher BMI in underweight or normal weight segments could reward employment probability for women and monthly wages for men. Such rewards of relatively higher monthly wages were also estimated for men in the overweight segment. Our findings suggest discrimination as one factor penalizing higher BMI in the labor market.

Background : The diagnosis-related group-based prospective payment programme was introduced in Korea in 1997 as a pilot programme to control health spending. In July 2013, the programme was implemented throughout the nation. The aim of our study is to evaluate the relationship between quality of care and market competition following the introduction of the new payment system in Korea. Methods : We conduct an observational analysis using National Health Insurance claim data from 2011 to 2014. We analyse data on readmission within 30 days, length of stay, and number of outpatient visits for 1742 hospitals and 821 912 cases. We use a generalized estimating equation model to evaluate readmission within 30 days and number of outpatient visits and a multi-level regression model to assess length of stay. Results : Total readmission within 30 days is 10 727 (1.3%). High competition areas present a lower risk of readmission [odds ratio (OR): 0.95, P : 0.0277], a longer length of stay (1%, P < 0.0001), and an increased number of outpatient visits (Relative Risk: 1.11, P : 0.0011) as compared with moderate competition areas. Risk of readmission is higher in low competition areas as compared with moderate competition areas (OR: 1.21, P < 0.0001). Conclusion: The effects of the introduction of the new payment system differed by degree of market competition. Thus, evaluation about the effect of new payment system on hospital performance should be measured in combination with the degree of hospital market structure.

Objectives We analyzed the effect of the outpatient prescription incentive program and price cuts of listed medicines in South Korea on prescription drug expenditures and prescription behaviors, focusing on antibiotics for the most common infectious diseases. Methods We used the National Health Insurance claims data from January 1, 2009 through December 31, 2012. For 1625 primary clinics randomly sampled, we included all claims with principal diagnoses of acute upper respiratory tract infections (URTIs, J00–J06), acute lower respiratory tract infections (LRTIs, J20–J22), or otitis media (H65, H66). An interrupted time-series analysis was conducted. Results Pharmaceutical spending per claim dropped immediately after the outpatient prescription incentive program only for otitis media (adults), but the secular trend shifted downward after the incentive program for all target diseases. The incentive program lowered the trend of antibiotic prescribing rate in otitis media (adults). The program was associated with an increase of the number of antibiotics prescribed in URTI (adults) and LRTI (children) and decrease in otitis media (adults). The broad markdown of drug prices reduced pharmaceutical expenditures immediately for all diseases, but without lasting effect. Conclusion The direct financial incentives to physicians to reduce in prescription spending had the intended effect over time and can be an important tool to improve pharmaceutical spending management.

Although taxes on regular soda and other forms of sugar-sweetened beverages have been proposed as a disincentive to consumption, little is known about the association of soda price with soda intake status or the potential heterogeneity across sub-population groups based on age. Such estimates cannot be obtained from aggregated sales or household purchase data because they do not break down soda intake by individuals. To fill this gap in the literature, the 24-h dietary recall data from the U.S. National Health and Nutrition Examination Surveys (1999–2008) have been merged with soda prices from the Council for Community and Economic Research (C2ER). The variation in soda prices across zip codes and over the years were used to identify the associations of soda prices with the prevalence of sugar-sweetened regular soda intake and caloric intake from soda for children (N = 8032), adolescents (N = 6501), and adults (N = 14,141). The analyses were further stratified by gender, race/ethnicity and income-based socioeconomic status. A 10% higher soda price was associated with lower prevalence (i.e., probability) of regular soda intake by 3.4%, 4.6% and 4.0% for children, adolescents, and adults, respectively, and lower caloric intake from soda by 8.1%, 5.2%, and 6.6%, respectively. The strongest negative associations between soda prices and regular soda intake were found among children and adults; the weakest negative associations were found among minority children and adolescents. By using individual-level data from the 24-h dietary recall data, we identified substantial heterogeneity in the association of soda price with regular soda intake. Our results add to the growing literature suggesting that higher soda prices are associated with reduced regular soda intake.

Objectives This study examined the influence of home and school environments, and individual health-risk behaviours on body weight outcomes in Korean adolescents. Study design This was a cross-sectional observational study. Methods Quantile regression models to explore heterogeneity in the association of specific factors with body mass index (BMI) over the entire conditional BMI distribution was used. A nationally representative web-based survey for youths was used. Results Paternal education level of college or more education was associated with lower BMI for girls, whereas college or more education of mothers was associated with higher BMI for boys; for both, the magnitude of association became larger at the upper quantiles of the conditional BMI distribution. Girls with good family economic status were more likely to have higher BMIs than those with average family economic status, particularly at the upper quantile of the conditional BMI distribution. Attending a co-ed school was associated with lower BMI for both genders with a larger association at the upper quantiles. Substantial screen time for TV watching, video games, or internet surfing was associated with a higher BMI with a larger association at the upper quantiles for both girls and boys. Dental prevention was negatively associated with BMI, whereas suicide consideration was positively associated with BMIs of both genders with a larger association at a higher quantile. Conclusions These findings suggest that interventions aimed at behavioural changes and positive parental roles are needed to effectively address high adolescent BMI.

The mortality and progression rates in osteosarcoma differ depending on the presence of metastasis. A decision model would be useful for estimating long-term effectiveness of treatment with limited clinical trial data. The aim of this study was to explore the lifetime effectiveness of the addition of mifamurtide to chemotherapy for patients with metastatic and nonmetastatic osteosarcoma. The target population was osteosarcoma patients with or without metastasis. A Markov process model was used, whose time horizon was lifetime with a starting age of 13 years. There were five health states: disease-free (DF), recurrence, post-recurrence disease-free, post-recurrence disease-progression, and death. Transition probabilities of the starting state, DF, were calculated from the INT-0133 clinical trials for chemotherapy with and without mifamurtide. Quality-adjusted life-years (QALY) increased upon addition of mifamurtide to chemotherapy by 10.5 % (10.13 and 9.17 QALY with and without mifamurtide, respectively) and 45.2 % (7.23 and 4.98 QALY with and without mifamurtide, respectively) relative to the lifetime effectiveness of chemotherapy in nonmetastatic and metastatic osteosarcoma, respectively. Life-years gained (LYG) increased by 10.1 % (13.10 LYG with mifamurtide and 11.90 LYG without mifamurtide) in nonmetastatic patients and 42.2 % (9.43 LYG with mifamurtide and 6.63 LYG without mifamurtide) in metastatic osteosarcoma patients. The Markov model analysis showed that chemotherapy with mifamurtide improved the lifetime effectiveness compared to chemotherapy alone in both nonmetastatic and metastatic osteosarcoma. Relative effectiveness of the therapy was higher in metastatic than nonmetastatic osteosarcoma over lifetime. However, absolute lifetime effectiveness was higher in nonmetastatic than metastatic osteosarcoma.

This paper tests for peer effects in obesity in a novel way. It addresses the reflection problem by using the alter’s genetic risk score for obesity, which is a significant predictor of obesity, is determined prior to birth, and cannot be affected by the behavior of others. It addresses the endogeneity of peer group formation by examining peers who are not self-selected: full siblings. We find evidence of positive peer effects in weight and obesity; having a sibling with a high genetic predisposition to obesity raises one’s risk of obesity, even controlling for one’s own genetic predisposition to obesity.

Background The prevalence of dyslipidemia, particularly hypercholesterolemia, has been reported to increase after pregnancy and menopause in Korea. This suggests the importance of the management of dyslipidemia in women for preventing cardiovascular diseases. Objective This study aimed to examine the association of breastfeeding with 5 subtypes of dyslipidemia in Korean women aged over 20 years, by using the nationally representative Korea National Health and Nutrition Examination Survey 2010–2014. Methods Ordinary least square regression and ordered logistic regression analyses were used to determine the association between breastfeeding duration and dyslipidemia. Results The likelihood of having low-density lipoprotein cholesterol (LDL-C) disorder decreased by 16% in the group that breastfed for more than 24 months (odds ratio, 0.84; 95% confidence interval, 0.75–0.95) compared with the group that did not breastfeed. The likelihood of having non–high-density lipoprotein cholesterol (non-HDL-C) disorder was significantly reduced by 25% when the breastfeeding duration was more than 24 months (odds ratio, 0.75; 95% confidence interval, 0.64–0.87). The tendency toward developing disorders of total cholesterol (TC), LDL-C, and non-HDL-C decreased as the duration of breastfeeding increased, particularly among women aged 30–39 years. Conclusion Breastfeeding duration was negatively correlated with dyslipidemia in terms of TC, LDL-C, non-HDL-C, and triglycerides. Long-term breastfeeding was associated with the prevalence of dyslipidemia-TC, LDL-C, non-HDL-C, and TG disorders, in particular.

Background Inappropriate antibiotic use significantly contributes to antibiotic-resistance, resulting in reduced antibiotic efficacy and increasing physical burden and cost of disease. The goal of this study was to explore antibiotic usage patterns in South Korea using 2007–2014 health insurance claims data. Methods We used the Health Insurance Review & Assessment Service data, which represents nearly the entire population of South Korea, to discern patterns in antibiotic prescribing practices. The daily dose, as defined by the World Health Organization ([defined daily doses]/1000 inhabitants/day, [DID]), was used as a measure of antibiotic use. Subgroup analyses were performed on the basis of patient characteristics (sex, age, and disease) and provider characteristics (type of medical institution). Results Antibiotic use in DID increased from 23.5 in 2007 to 27.7 in 2014. The ≤ 6 years old age group showed the highest level of usage at 59.21 DID in 2014, and showed an increasing trend each year. DIDs of beta-lactam antibacterials, penicillins (J01C), other beta-lactam antibacterials (J01D), lincosamides and streptogramins (J01F), quinolone antibacterials (J01M), and other antibacterials (J01X) increased over time. Conclusion This study provides valuable statistics regarding antibiotic usage in South Korea; this is important for guiding health policy with regard to antibiotic usage. There is a need for further study exploring antibiotics use and resistance.

This study aimed to investigate the prevalence of potential unnecessary injection (PUNI) and to identify factors associated with frequent PUNI uses. Population-based National Health Insurance claims data for outpatient health care settings during the six month period from July to December 2011 were retrospectively reviewed. Patients aged 18-80 without severe diseases and visited healthcare centers more than 25 times during study period were included. PUNI was defined as injection used where substitutable oral agents were available and where injection uses are not warranted. A total of 801,532 patients were included for this analysis. Among them, 29.0 % were frequent PUNI user defined as ≥10 PUNI used during the study period. In multivariate logistic regression results revealed significant associations between frequent PUNI use and several patient and healthcare utilization factors. Women than men, elderly than younger people, residents in rural areas than in big cities, and more frequent visitors to healthcare centers than less frequent visitors were more likely to be frequent PUNI users. Larger number of healthcare center utilized and higher out-of-pocket expense level showed significant lower risks of frequent PUNI uses. Identified factors associated with frequent PUNI use in this study could be the targets to develop programs for reducing injection overuse.

Objective To investigate the association between potentially inappropriate medicine (PIM) use, defined using the American Geriatric Society (AGS) 2012 Beers criteria, and the risk of hospitalization or emergency department (ED) visits in elderly patients, and to examine the most frequently used PIMs among patients with adverse outcomes. Design/setting This was a retrospective study using National Health Insurance claims data from 2010 to 2012. Intervention(s) Elderly patients who took PIMs are compared to those who were not taking PIMs. Study participants Elderly patients (n = 79 552) who visited medical institutions in Jeju Island during 2011. Main outcome measure Hospitalization and ED visits were evaluated according to whether the patients took PIMs during the study period. The most frequent medications used by the PIM group were also investigated. Results The likelihood of hospitalization was higher in older patients who took at least one PIM than in those who were not taking PIMs during the study period (odds ratio 2.25, 95% confidence interval 2.09-2.44). Patients taking PIMs were more likely to visit EDs (odds ratio 1.59, 95% confidence interval 1.50-1.67). Among patients who were hospitalized or visited EDs, 45.5% had taken at least one PIM on that day. The most commonly used PIMs included chlorpheniramine maleate, diazepam, metoclopramide HCl and diclofenac sodium. Conclusion Our findings indicate that PIM use can lead to negative health consequences, providing further evidence of the inappropriateness of these medications. Thus, pharmaceutical policies regarding PIM use may need to be implemented for elderly adults in Korea.

This study aimed to estimate treatment costs attributable to overweight and obesity in patients with diabetes who were less than 65 years of age in the United States.This study used data from the Medical Expenditure Panel Survey from 2001 to 2013. Patients with diabetes were identified by using the International Classification of Diseases, Ninth Revision, Clinical Modification code (250), clinical classification codes (049 and 050), or self-reported physician diagnoses. Total treatment costs attributable to overweight and obesity were calculated as the differences in the adjusted costs compared with individuals with diabetes and normal weight. Adjusted costs were estimated by using generalized linear models or unconditional quantile regression models.The mean annual treatment costs attributable to obesity were $1,852 higher than those attributable to normal weight, while costs attributable to overweight were $133 higher. The unconditional quantile regression results indicated that the impact of obesity on total treatment costs gradually became more significant as treatment costs approached the upper quantile.Among patients with diabetes who were less than 65 years of age, patients with diabetes and obesity have significantly higher treatment costs than patients with diabetes and normal weight. The economic burden of diabetes to society will continue to increase unless more proactive preventive measures are taken to effectively treat patients with overweight or obesity.

Objectives This study aimed to evaluate the impact of high anticholinergic burden on overall emergency department (ED) visits and ED visits related to adverse effects of anticholinergic drugs among older adults. Methods For this retrospective cohort study, we used claims data from older adults with high representativeness. The average daily Anticholinergic Risk Scale (ARS) score was calculated based on the dosage, treatment duration, and potency of anticholinergic drugs during three months. A high-exposure group (ARS ≥ 2) and a non-exposure group were included in this analysis. The primary outcome was the first ED visit during the follow-up period. Anticholinergic ED visits were defined as ED visits with a main diagnosis of a fall, fracture, dizziness, delirium, constipation, or urinary retention. Results In total, 118,750 subjects (43.6% male) were included in this study. The mean age was 75.4 ± 6.6 years. The adjusted hazard ratios (aHRs) for all-cause and anticholinergic ED visits among those with high ARS scores were 1.28 (95% CI: 1.20–1.36) and 1.55 (95% CI: 1.38–1.74), respectively. The high-exposure group was at higher risk than the non-exposure group for ED visits for falls or fractures (aHR: 1.31, 95% CI: 1.07–1.60), dizziness (aHR: 1.71, 95% CI: 1.36–2.14), delirium (aHR: 2.05, 95% CI: 1.13–3.73), constipation (aHR: 1.65, 95% CI: 1.35–2.02) and urinary retention (aHR: 1.66, 95% CI: 1.30–2.12). Conclusions This study demonstrated that a high anticholinergic burden in older adults increased the risk of all-cause ED visits, anticholinergic ED visits and specific-cause ED visits.

Background Necrotizing fasciitis (NF) is a rare but fatal infectious disease that causes economic burdens on patient and the healthcare system. We investigated the incidence of necrotizing fasciitis (NF) and the seasonal variation of necrotizing fasciitis in Korea. Methods We analyzed a nationwide claims database from the Korean Health Insurance Review and Assessment Service from 2011 to 2017. For case definition, we used two different methods. First, patients who hospitalized with NF diagnosis code and received surgical intervention (NF code method) were defined as NF. Second, patients hospitalized with sepsis codes accompanying surgical intervention codes were defined as NF (sepsis code method). The annual incidence rate per 100,000 population of NF was calculated using the number of identified NF cases as numerator and age- and sex-specific midyear population as the denominator. Poisson regression models were used to assess the relationship of crude incidence rates to year, age, and sex. A multivariate Poisson regression model was used to investigate variations in trends in the monthly NF cases. Results The overall average annual incidence rate of NF during 2012–2017 was 0.86/100,000 by NF code method and 1.47/100,000 by the sepsis code method. The incidence of NF increased with age and 2.5 times higher in males than females across all age groups. Two-thirds of episodes occurred in diabetes patients. The incidence of NF occurred the most during summer. A multivariate Poisson regression model using national meteorological variables suggested that higher mean temperature of and larger numbers of NF cases during a prior month increased NF cases. Conclusion The possibility of NF should be suspected for the cases for an elderly man with diabetes in summer. From a national management perspective, the prior information on the number of NF incidences and the mean temperature can help predict NF outbreak. Disclosures All authors: No reported disclosures.

Objective To develop a reliable food store observational data collection instrument to be used for measuring product availability, pricing, and promotion. Design Observational data collection. Setting A total of 120 food stores (26 supermarkets, 34 grocery stores, 54 gas/convenience stores, and 6 mass merchandise stores) in the Chicago metropolitan statistical area. Main Outcome Measures Inter-rater reliability for product availability, pricing, and promotion measures on a food store observational data collection instrument. Analysis Cohen's kappa coefficient and proportion of overall agreement for dichotomous variables and intra-class correlation coefficient for continuous variables. Results Inter-rater reliability, as measured by average kappa coefficient, was 0.84 for food and beverage product availability measures, 0.80 for interior store characteristics, and 0.70 for exterior store characteristics. For continuous measures, average intra-class correlation coefficient was 0.82 for product pricing measures; 0.90 for counts of fresh, frozen, and canned fruit and vegetable options; and 0.85 for counts of advertisements on the store exterior and property. Conclusions and Implications The vast majority of measures demonstrated substantial or almost perfect agreement. Although some items may require revision, results suggest that the instrument may be used to reliably measure the food store environment.

Purpose. To explore the relationships of selected health behaviors to medication adherence. Design. A retrospective cohort study. Setting. Data from Korean national health insurance claims between January 2010 and June 2011. Subjects. Patients aged 65 years and older with hypertension (N = 662,170), hyperlipidemia (N = 244,702), or diabetes (N = 179,285). Measures. Medication adherence as a medication possession ratio from January to June 2011 as a dependent variable. The waist circumference (cm) and the body mass index (weight in kilogram divided by height in meter squared) as a marker for obesity. Smoking, drinking, and physical activity as main independent variables. Analysis. A multivariate logistic regression. Results. Nonobese patients, as based on the waist circumference, were more likely to adhere to their medication (by 8.9% for hypertension, 6.2% for diabetes, and 3.5% for hyperlipidemia). Current smokers were less likely to adhere to their medication (by 8.7% for hypertension and 6.8% for diabetes), and moderate and heavy drinkers were also less likely to show medication adherence for diabetes (by 12.9% and 6.4%). Mild physical activity was related to a 1.1% to 1.8% increase in the likelihood of medication adherence across the three disease groups. Conclusion. Health promotion programs for self-care health behaviors of elderly patients should emphasize good medication adherence to achieve successful self-management of diseases.

Skipping breakfast can be potentially harmful because breakfast consumption is considered one of the important health-related behaviors that benefit physical and mental health. As the rate of depression has increased recently, we investigated the association between the frequency of eating breakfast and depression in adults. We obtained the data from the 2013 Korean Community Health Survey; a total of 207,710 survey participants aged 20 years or over were studied. Participants were categorized into three groups by the frequency of breakfast consumption as follows: “seldom,” “sometimes,” and “always.” We performed a multiple logistic regression to investigate the association between breakfast consumption and depressive mood. Subgroup analyses were conducted by stratifying socioeconomic variables controlling for variables known to be associated with depressive symptoms. Participants who had breakfast seldom or sometimes had higher depressive symptoms than those who always ate breakfast (“seldom”: OR = 1.43, 95% CI 1.36–1.52; “sometimes”: OR = 1.32, 95% CI 1.23–1.40). Subgroup analyses showed that this association was more marked in those who were 80 years or older, those who had low household income, or those with elementary school education level or less. The result of this study suggests that lack of breakfast consumption is associated with depression among adults with different socioeconomic factors.

We assessed the impact on physician prescription behaviors of an outpatient prescription incentive program providing financial rewards to primary care physicians for saving prescription costs in South Korea. A 10% sample of clinics (N = 1,625) was randomly selected from all clinics in the National Health Insurance claims database for the years 2009–2012, and all claims with the primary diagnosis of peptic ulcer or gastro-esophageal reflux diseases were extracted from those clinics’ data. A clinic-level random-effects model was used. After the program, clinics in general medicine showed a lower prescription rate (by 0.8 percentage points), lower number of medicines prescribed (by 0.02), lower prescription duration (by 0.15 days), and lower drug expenditure per claim (by 740 won). Small clinics on the

The Price-Volume Agreement Program (PVAP) was promulgated in 2007 in South Korea as the first attempt to adjust drug pricing according to total consumption in order to contain drug expenditure. This study was designed to assess the impact of the PVAP on diabetes drug expenditure for a period of a 10-year period (2003-2012) using claims data from the National Health Insurance Service. We estimated a multilevel mixed-effects linear regression model by comparing the level of total monthly diabetes drug expenditure for drugs subject to PVAP and existing drugs after adjusting the average differences in drug expenditure before and after the PVAP. The monthly total expenditure for drugs that were newly listed through the PVAP (negotiation drugs) was 7.03% higher on average compared to that for existing drugs, controlling for the baseline differences in expenditure before and after the PVAP. This increase was observed in all four subgroups of diabetes drugs, including sitagliptin, vildagliptin, exenatide, and others. The growth rate of total diabetes drug expenditure was reduced after the PVAP despite the sustained escalation of expenditure levels, which may imply that the PVAP has the potential to be an effective tool for drug expenditure control in the long term.

OBJECTIVE This study was designed to investigate patient responses to a medication counseling intervention program piloted by the National Health Insurance Service (NHIS), the national health insurer in Korea, to improve medication management in patients with hypertension, hyperlipidemia, or diabetes. METHODS AND MATERIALS Interventions were conducted from July to September 2013 through direct mailing followed by two telephone-initiated counseling sessions for the medication discontinuation group (< 80% medication possession ratio (MPR) and ≥ 2 months of discontinuation) and the medication over-possession group (≥ 150% MPR). The telephone intervention was applied through two models: model 1 (counseling by NHIS staff only) and model 2 (counseling by NHIS staff with contract-based working pharmacists in community pharmacies). Multivariate logistic regression analysis was performed to identify factors affecting favorable responses of patients to the telephone-initiated intervention. Patient responses to the telephone-initiated intervention were evaluated by a counselor. RESULTS In all, 891 patients were counseledvia telephone. Patient responses to the telephone-initiated intervention were favorablein 57.6%, neutral in 17.4% and not favorable in 24.9% overall. Counseling by NHIS staff together with pharmacists (model 2) produced more favorable responses from patients than counseling by NHIS staff alone (model 1) (OR 2.73, 95% CI 1.97 - 3.77). CONCLUSION Our findings of favorable responses to interventions support a personalized approach by the NHIS to improve patient behavior for medication adherence.

Background Eating food away from home and restaurant consumption have increased over the past few decades. Purpose To examine recent changes in calories from fast-food and full-service restaurant consumption and to assess characteristics associated with consumption. Methods Analyses of 24-hour dietary recalls from children, adolescents, and adults using nationally representative data from the 2003–2004 through 2007–2008 National Health and Nutrition Examination Surveys, including analysis by gender, ethnicity, income, and location of consumption. Multivariate regression analyses of associations between demographic and socioeconomic characteristics and consumption prevalence and average daily caloric intake from fast-food and full-service restaurants. Results In 2007–2008, 33%, 41%, and 36% of children, adolescents, and adults, respectively, consumed foods and/or beverages from fast-food restaurant sources and 12%, 18%, and 27% consumed from full-service restaurants. Their respective mean daily caloric intake from fast food was 191, 404, and 315 kcal, down by 25% ( p ≤0.05), 3%, and 9% from 2003–2004; and among consumers, intake was 576, 988, and 877 kcal, respectively, down by 12% ( p ≤0.05), 2%, and 7%. There were no changes in daily calories consumed from full-service restaurants. Consumption prevalence and average daily caloric intake from fast-food (adults only) and full-service restaurants (all age groups) were higher when consumed away from home versus at home. There were some demographic and socioeconomic associations with the likelihood of fast-food consumption, but characteristics generally were not associated with the extent of caloric intake among those who consumed from fast-food or from full-service restaurants. Conclusions In 2007–2008, fast-food and full-service restaurant consumption remained prevalent and a source of substantial energy intake.

We explored the extent to which economic contextual factors moderated the association of Supplemental Nutrition Assistance Program (SNAP) participation with body mass index (BMI) among low-income adults whose family income (adjusted for family size) is less than 130% of the federal poverty guideline. We drew on individual-level data from the Panel Study of Income Dynamics in the United States, including three waves of data in 1999, 2001, and 2003. Economic contextual data were drawn from the American Chamber of Commerce Researchers Association for food prices and Dun & Bradstreet for food outlet measures. In addition to cross-sectional estimation, a longitudinal individual fixed effects model was used to control for permanent unobserved individual heterogeneity. Our study found a statistically significant joint moderating effect of the economic contextual factors in longitudinal individual fixed effects model for both women (BMI only) and men (both BMI and obesity). For both women and men, SNAP participants' BMI was statistically significantly lower if they faced increased numbers of available supermarkets/grocery stores in the longitudinal model. A simulated 20% reduction in the price of fruits and vegetables resulted in a larger decrease in BMI among SNAP participants than non-participants for women and men, whereas a simulated 20% increase in the availability of supermarkets and grocery stores resulted in a statistically significant difference in the change in BMI by SNAP participation for women but not for men. Policies related to economic contextual factors, such as subsidies for fruits and vegetables or those that would improve access to supermarkets and grocery stores may enhance the relationship between SNAP participation and body mass outcomes among food assistance program participants.

I. INTRODUCTION Average adult body mass index (BMI: weight in kilograms divided by height in meters squared) in the United States increased approximately 12% between the 1960s and 2004 (Regal et al. 2009) and approximately one third of the U.S. adults were estimated to be obese in 2007-2008 (Flegal et al. 2010). At the same time, the proportion of expenditure on food away from home out of total food expenditure more than doubled between 1960 and 2008 from 19.7% to 41.4% (USDA 2011). In particular, the proportion of sales of food away from home at limited service restaurants increased from 9.7% to 37.1% between 1963 and 2008 (USDA 2011). Data on nationwide surveys of food consumption patterns and household expenditures also show a marked upward trend in total energy intake derived from away-from-home sources, in particular for fast food outlets (Guthrie, Lin, and Frazao 2002: Nielsen, Siega-Riz, and Popkin 2002; Stewart et al. 2004). Fast food consumption was found to be associated with higher total energy intake and higher intake of fat, saturated fat, carbohydrates, sugar, and carbonated soft drinks and lower intake of micronutrients and fruit and vegetables (Binkley. Eales, and Jekanowski 2000; Bowman et al. 2004; Bowman and Vinyard 2004; French et al. 2001; French, Hamack, and Jeffery 2000; Paeratakul et al. 2003) and has been associated with higher body weight (Binkley, Eales, and Jekanowski 2000; Bowman and Vinyard 2004; Guthrie, Lin, and Frazao 2002). Recently, researchers have explored the importance of food prices as a modifiable economic contextual factor to combat the obesity epidemic given that food prices have fallen, whereas the opportunity cost of physical activity has risen over time (Cutler, Glaeser, and Shapiro 2003; Lakdawalla, Philipson, and Bhattacharya 2006). Particularly, understanding the effect of fast food prices on body weight is important because it provides evidence on the extent to which food pricing policies such as taxes on energy dense foods may be effective policy tools to reverse such an epidemic. Lower fast food prices have been reported to be statistically significantly associated with higher weight outcomes among adolescents (Auld and Powell 2009; Powell 2009; Powell et al. 2007) and children in low-socioeconomic families (Powell and Bao 2009). Particularly, the price elasticity of body weight outcomes with regard to fast food prices was found to be heterogeneous over the conditional distribution of BMI for adolescents in a cross-sectional analysis with larger associations at higher BMI quantiles (Auld and Powell 2009). However, the evidence is not as consistent for adults. Chou, Grossman, and Saffer (2004) reported that higher prices of full-service restaurants and fast food restaurants (BMI only) were statistically significantly associated with lower BMI and obesity prevalence among adults. However, another study found that the association between fast food prices and adult weight was statistically insignificant (Beydoun. Powell, and Wang 2008). This study builds on the previous studies and examines the heterogeneous relationship between fast food prices as a proxy for energy dense food away from home and adult body weight outcomes in the United States using data for adults drawn from a nationally representative longitudinal study. We estimate an individual fixed effect quantile regression model of the linear measure of BMI on food prices to estimate changes in the nature, direction, and magnitude of the relationship between fast food prices and body weight outcomes over the conditional distribution of BMI. The quantile regression model allows capturing any changes in the conditional dispersion of BMI associated with fast food prices, whereas typical mean estimation such as ordinary least squares (OLS) only accounts for changes in the mean value. If, for example, fast food prices are associated with individuals' weight only in the top or bottom of the distribution of BMI, the conditional distribution of BMI from OLS estimation would become thinner and wider without any changes in the mean value. …

This study used direct field observations with interior assessments of outlets to validate food store and restaurant data from two commercial business lists conditional on classification of outlet type, including supermarkets, grocery stores, convenience stores, full-service restaurants and fast food restaurants. The study used a stratified random sample that included 274 urban census tracts across 9 counties from the Chicago Metropolitan Statistical Area (MSA) and 46 suburban and 61 rural census tracts across 13 counties from a 50-mile buffer surrounding the MSA. Results showed that agreement between the field observations and the commercial business lists for the food store and restaurant outlets was generally moderate (ranging from fair to good). However, when the listed data were validated based on an exact classification match, agreement was only fair (ranging from poor to moderate) and, in particular, poor for fast food restaurants. The study also found that agreement levels for some outlet types differed by tract characteristics. Commercial databases must be used with caution as substitutes for on the ground data collection.

This study explores the heterogenous relationship between Food Stamp Program (FSP) participation and body mass index (BMI) for low income individuals whose per capita family income falls in the bottom two quintiles. We estimate changes in the dispersion of the entire distribution of BMI following FSP participation using a quantile regression model in both cross-sectional and longitudinal analyses. For women, we find that the mean OLS estimate of FSP participation underestimates the extent of the positive association with BMI at the top quantiles in both cross-sectional and longitudinal individual fixed effects models. Controlling for individual fixed effects in the quantile regression model reduces the estimated magnitude of the association by a factor of three to four, although the estimates remain statistically significant for women. For men, a marginally statistically significant positive association of FSP participation with BMI is found at the top quantiles compared to no statistically significant mean estimate although the association is no longer statistically significant when time-constant individual heterogeneity is adjusted for in the individual fixed effect models.

Health economics has a tradition of evaluating the models of instrumental variables (IV) used in our field. For example, French and Popovici (2011) assess the instruments used in 60 recent studies measuring the effect of substance use (alcohol, illicit drugs, and tobacco) on various outcomes. Rashad and Kaestner (2004) evaluate the instruments used by Sen (2002) and Rees and colleagues (2001) to identify the effect of alcohol on risky sex among adolescents. Terza et al. (2008) review the health economics literature that applies linear IV methods in inherently nonlinear regression settings. In this editorial we discuss the IVs used in Fletcher and Lehrer (2009a), hereafter FL, to estimate the effect of health conditions on educational attainment. We focus on FL because it is novel, well-written, and careful in many ways; it won the 2009 Victor R. Fuchs award for ‘the best research paper with the potential to spawn new research in an underdeveloped area of health economics or health policy’. The use of genes as IVs (and in other empirical capacities) is likely to become more widespread as large social science datasets continue to add data from genetic assays. Therefore, consideration of this method is timely and likely to be useful in the future. Our comments should not be interpreted as exclusively about FL, but also apply to other papers in this emerging area of empirical health economics (e.g. Ding et al., 2009; Fletcher and Lehrer, 2009b), including our own (Norton and Han, 2008). FL estimate IV models using data from the third wave of the National Longitudinal Survey of Adolescent Health (Add Health) to test whether overweight (based on self-reported weight and height), depression (based on the 20-item Center for Epidemiologic Studies-Depression Scale), and attention deficit and hyperactivity disorder or ADHD (based on 18 retrospective questions) affect years of schooling completed when respondents were on average 22 years old. FL argue persuasively that these measures of physical and mental health are endogenous to educational attainment. For example, poor grades in school may contribute to depression (reverse causality) and unobserved factors, such as rate of time preference, may contribute to both poor health and worse educational outcomes. As a result, simple regression would result in biased estimates of the effect of health on educational attainment. FL address the endogeneity of health by using genes as IVs. The specific IVs they use, listed in column 1 of Table I, are genes related to the neurotransmitters dopamine and serotonin. Fletcher and Lehrer (2009b) note that geneticists have linked these specific genes to overweight, depression, and ADHD, and that these correlations make sense in light of the fact that neurotransmitters affect mood, attention, and are associated with feelings of pleasure and reward, and thus serve as positive reinforcement for certain decisions. For example, people who are genetically predisposed to low levels

Purpose This study examined the associations of prices of food at home groceries, prices of fast food away from home and the availability of food stores and restaurants with the number of days over the past week that adolescents consumed fruit and fruit juices, vegetables, meat, nonmeat protein, dairy, grains, and sweets. Methods Individual-level data on adolescents were drawn from the Child Development Supplement of the Panel Study of Income Dynamics combined at the zip code level with external economic contextual data. Multivariate regression analyses were used to estimate the associations between food consumption categories and the economic contextual factors. Regressions were also estimated by households' poverty status. Results Fast food and food at home prices were not significantly associated with any of the food consumption categories in the full sample. However, among poor adolescents, higher fast food prices were associated with higher levels of nonmeat protein consumption. Food store outlet availability was found to have very small significant associations with some food consumption categories but no significant associations were found for restaurant outlets. Conclusions Food away from home prices such as fast food prices and supermarket and grocery store availability were associated with some food consumption categories among low-income youths and related policies deserve further examination.

Adolescents have poor dietary behaviors and high overweight prevalence. Economic contextual factors such as food prices and food store and restaurant availability are hypothesized and increasingly being explored empirically as contributors to the obesity epidemic. Evidence showed that healthful compared with less healthful foods increasingly cost more and that fast food restaurants are increasingly available. In addition, racial, ethnic, and socioeconomic disparities have been documented in access to food outlets, particularly chain supermarkets, and such disparities have been shown to be increasing recently. Empirical evidence based on nationally representative U.S. adolescent data revealed that lower fruit and vegetable prices, higher fast food prices, and greater supermarket availability were related to higher fruit and vegetable consumption and lower BMI, in particular for BMI among teens who are overweight or at risk for overweight and who are low- to middle-socioeconomic status. The availability of fast food restaurants was not associated with youth BMI. Overall, this research implies that pricing interventions of taxes on energy-dense foods such as fast food and/or subsidies to healthful foods such as fruits and vegetables and policy efforts to improve access to supermarkets may help to improve adolescent weight outcomes.

Past empirical work has shown a negative relationship between the body mass index (BMI) and wages in most cases. We improve on this work by allowing the marginal effect of non-linear BMI groups to vary by gender, age, and type of interpersonal relationships required in each occupation. We use the National Longitudinal Survey of Youth 1979 (1982-1998). We find that the often-reported negative relationship between the BMI and wages is larger in occupations requiring interpersonal skills with presumably more social interactions. Also, the wage penalty increases as the respondents get older beyond their mid-twenties. We show that being overweight and obese penalizes the probability of employment across all race-gender subgroups except black women and men. Our results for the obesity-wage association can be explained by either consumers or employers having distaste for obese workers.

The prevalence of incontinence ranges from 11% to 34% among community-dwelling men agedor =65 years.The objective of this analysis was to determine the nature of incontinence diagnosed in men with benign prostatic hypertrophy (BPH), focusing on its incidence, prevalence, diagnostic workup, and management.A cohort of patients with BPH was identified in the Integrated Healthcare Information Services National Managed Care Benchmark Database (1997-2003). Age and duration in the database after the first diagnosis of BPH were used as matching strata. Therapeutic subgroups consisted of watchful waiting, alpha-blockers, 5-alpha-reductase inhibitors (5ARIs), and BPH-related surgery.A total of 411,658 males with BPH were identified from 12,298,027 males (3.3%). Of the BPH cohort, 2.7% (n = 11,172) were identified as having incontinence; of these, 57.8% of patients wereor =65 years of age. Alter applying inclusion/exclusion criteria, the final matched case-control sample included 6346 men as case subjects and 229,154 men as control subjects. The overall incidence of incontinence in this BPH sample was 1835/100,000/year, and the prevalence was 2713/100,000 men. In 48.5% of the incontinent men, the type of incontinence was not specified. Diagnostic testing was performed in 2.9% of men with incontinence. Conditional logistic regression analyses found that BPH-related surgery and alpha-blocker use increased the adjusted odds ratio for the risk of incontinence 3.1-fold, and 1.1- to 1.7-fold, respectively. The odds ratio of the risk of incontinence was not significantly increased with long-term 5ARI use.Use of alpha-blockers, 5ARIs for the short term (1 year), and BPH-related surgery were independently, significantly associated with BPH-related incontinence; 5ARI use for1 year and watchful waiting were not. BPH-related incontinence may be related to progression of BPH or as a postsurgical complication. Patients with BPH should be asked specifically about incontinence, especially after BPH-related surgery, and undergo a full diagnostic workup for the diagnosis of urinary incontinence.

Background Overweight/obesity is a growing health risk in Korea. The impact of overweight/obesity on pharmaceutical expenditure can be larger if individuals have multiple risk factors and multiple comorbidities. The current study estimated the combined effects of overweight/obesity and other unhealthy behaviors on pharmaceutical expenditure. Methods An instrumental variable quantile regression model was estimated using Korea Health Panel Study data. The current study extracted data from 3 waves (2009, 2010, and 2011). Results The final sample included 7148 person-year observations for adults aged 20 years or older. Overweight/obese individuals had higher pharmaceutical expenditure than their non-obese counterparts only at the upper quantiles of the conditional distribution of pharmaceutical expenditure (by 119% at the 90th quantile and 115% at the 95th). The current study found a stronger association at the upper quantiles among men (152%, 144%, and 150% at the 75th, 90th, and 95th quantiles, respectively) than among women (152%, 150%, and 148% at the 75th, 90th, and 95th quantiles, respectively). The association at the upper quantiles was stronger when combined with moderate to heavy drinking and no regular physical check-up, particularly among males. Conclusion The current study confirms that the association of overweight/obesity with modifiable unhealthy behaviors on pharmaceutical expenditure is larger than with overweight/obesity alone. Assessing the effect of overweight/obesity with lifestyle risk factors can help target groups for public health intervention programs.

In November 2006, 727 combination drugs in 24 therapeutic classes were delisted in the national formulary in Korea to reduce the country's pharmaceutical expenditure, making these 727 drugs non-reimbursable. This study examines the effects of this delisting on national health insurance expenditures for pharmaceuticals. An interrupted time series analysis was conducted for the period from January 2005 to August 2007 by using administrative claims from Korea's National Health Insurance. The main outcome variable was the total pharmaceutical expenditure measured as a whole and based on the level of health care institutions and therapeutic classes. Comparison between exposure group (delisted drugs) and non-exposure group (listed drugs) were done. No changes in the level of or trend in the total pharmaceutical expenditure were detected. However, the delisting reduced pharmaceutical expenditures in clinics. Delisting effects were also observed according to therapeutic classes of drugs. The results indicate that any delisting should take into account the type of drug.

Gregory PC, Han E, Morozova O, Kuhlemeier KV: Do racial disparities exist in access to inpatient stroke rehabilitation in the state of Maryland? Am J Med Phys Rehabil 2006;85:814–819. Black patients tend to have a greater number and severity of stroke cases. The literature on access to rehabilitative services shows mixed results ranging from no disparities to limited access among minority populations. This study evaluated the association of race and acute discharge to inpatient stroke rehabilitation in Maryland, a diagnostic related group–and postacute care prospective payment system–exempt state. Data from the Maryland Health Services and Cost Review Commission database for 2000 was used to conduct a cross sectional retrospective review to determine the rate of disposition to inpatient rehabilitation facilities (IRF). Multiple logistic regression analyses evaluated factors associated with discharge to IRF in this population. There were a total of 12,208 patients hospitalized with stroke in the year 2000. Compared with urban-dwelling white patients, black patients who lived in urban dwellings were more likely to be discharged to IRF, OR 1.42, 95% CI (1.06, 1.91). In the state of Maryland, urban-dwelling black stroke patients were more likely to be discharged to IRF acutely after stroke. Future studies should assess whether this trend persists in states that have larger rural populations.

The current study explores the association between body mass and job quality, a composite measurement of job characteristics, for adults. We use nationally representative data from the Korean Labor and Income Panel Study for the years 2005, 2007, and 2008 with 7282 person-year observations for men and 4611 for women. A Quality of Work Index (QWI) is calculated based on work content, job security, the possibilities for improvement, compensation, work conditions, and interpersonal relationships at work. The key independent variable is the body mass index (kg/m 2 ) splined at 18.5, 25, and 30. For men, BMI is positively associated with the QWI only in the normal weight segment (+0.19 percentage points at the 10th, +0.28 at the 50th, +0.32 at the 75th, +0.34 at the 90th, and +0.48 at the 95th quantiles). A unit increase in the BMI for women is associated with a lower QWI at the lower quantiles in the normal weight segment (−0.28 at the 5th, −0.19 at the 10th, and −0.25 percentage points at the 25th quantiles) and at the upper quantiles in the overweight segment (−1.15 at the 90th and −1.66 percentage points at the 95th quantiles). The results imply a spill-over cost of overweight or obesity beyond its impact on health in terms of success in the labor market.

Objectives To assess TV fast food ad exposure in South Korea. Methods We assessed time trends of targeted ratings (licensed from Nielsen Media Research Korea) by household income and education during 2004-2010. Results Lower income groups saw more fast food TV ads during the study period. Exposure decreased in all income groups with a bigger income gap in 2010 than in 2004. The relative exposure to local fried chicken franchise TV ads surged from one fifth in 2004 to half of all TV fast food ads seen in 2010 in all socioeconomic status (SES). Conclusions Future studies should assess the link between TV fast ood ad exposure, an important contextual factor for individual food choices, and actual consumption.

Background The rapid growth of prescription drug expenditures is a major problem in South Korea. Accordingly, the South Korean government introduced a positive listing system in 2006. They also adopted various price reduction policies. Nevertheless, the total expenditure for lipid-lowering drugs have steadily increased throughout South Korea. The present study explores the factors that have influenced the increased expenditures of lipid-lowering drugs with a particular focus on the effects of statins in this process. Methods This paper investigates the National Health Insurance claims data for prescribed lipid-lowering drugs collected between January 1, 2005 and December 31, 2009. We specifically focused on statins and assessed the yearly variation of statin expenditure by calculating the increased rate of paired pharmaceutical expenditures over a 2 year period. Our study classified statins into three categories: new entrants, core medicines and exiting medicines. For core medicines, we further examined influencing factors such as price, amount of drugs consumed by volume, and prescription changes (substitutes for other drug). Results Statin expenditure showed an average annual increase of 25.7% between 2005 and 2009. Among the different statins, the expenditure of atorvastatin showed a 36.6% annual increase rate, which was the most dramatic among all statins. Also we divided expenditure for core medicines by the price factor, volume factor, and prescription change. The result showed that annual weighted average prices of individual drug decreased each year, which clearly showed that price influenced statin expenditure in a negative direction. The use of generic drugs containing the same active ingredient as name-brand drugs increased and negatively affected statin expenditure (Generic Mix effect). However, the use of relatively expensive ingredients within statin increase, Ingredient Mix effect contributed to increased statin expenditure (Ingredient Mix effect). In particular, the volume effect was found to be critical for increasing statin expenditure as the amount of statin consumed increased steadily throughout the study period. Conclusions The recent rapid increase in statin expenditure can largely be attributed to an increase in consumption volume. In order to check drug expenditures effectively in our current situation, in which chronic diseases remain steadily on the rise, it is necessary to not only have supply-side initiatives such as price reduction, but also demand-side initiatives that could control drug consumption volume, for example: educational programs for rational prescription, generic drug promotional policies, and policies providing prescription targets.

Targeting repeated injection users with education interventions aimed at highlighting the extent of their current use and increasing awareness of the oral preparation options may reduce unnecessary injection use. The aim of this retrospective observational study was to investigate the patient factors related to repeated use of injection formulation analgesics in patients with musculoskeletal disorders who were frequent users of ambulatory healthcare services. Population-based national health insurance claims data for the time period July 2011 - December 2011 were analyzed. Patients aged 18 - 80 years with a musculoskeletal disorder, attended ambulatory healthcare settings > 25 times, and were prescribed pain relievers such as non-steroidal anti-inflammatory drugs and narcotic analgesics in an oral formulation for ≥ 14 days or in an injection formulation ≥ 3 times during the study period were included in the study. There were 742,675 repeated systemic analgesic users, and 64.1% (n = 476,021) of these patients were injection users. The average use of injections per patient during the 6-month period was 8.3. Tramadol was the most frequently prescribed medication for injection, followed by diclofenac, piroxicam, and ketorolac. Statistical analyses showed significant correlations between prevalent injection formulation use and patient factors such as gender, age, area of residence, days of healthcare utilization, number of healthcare centers visited, type of healthcare center visited, total medical expenditure, and total out-of-pocket expenditure. These factors could possibly be used to determine the target population for educational interventions aimed at changing behavior relating to the preference for injectable formulations.

Objectives The aim of this study was to explore the heterogeneous association of consumption of food away from home (FAFH) with individual body mass outcomes including body mass index and waist circumference over the entire conditional distribution of each outcome. Methods Information on 16 403 adults obtained from nationally representative data on nutrition and behavior in Korea was used. A quantile regression model captured the variability of the association of FAFH with body mass outcomes across the entire conditional distribution of each outcome measure. Heavy FAFH consumption was defined as obtaining ≥1400 kcal from FAFH on a single day. Results Heavy FAFH consumption, specifically at full-service restaurants, was significantly associated with higher body mass index (+0.46 kg/m 2 at the 50th quantile, 0.55 at the 75th, 0.66 at the 90th, and 0.44 at the 95th) and waist circumference (+0.96 cm at the 25th quantile, 1.06 cm at the 50th, 1.35 cm at the 75th, and 0.96 cm at the 90th quantiles) with overall larger associations at higher quantiles. Findings of the study indicate that conventional regression methods may mask important heterogeneity in the association between heavy FAFH consumption and body mass outcomes. Conclusion Further public health efforts are needed to improve the nutritional quality of affordable FAFH choices and nutrition education and to establish a healthy food consumption environment.