Trends in Secondhand Smoking and Urine Cotinine Concentration in Non-Smoking Adults in Korea: The 2008–2011, 2014–2018 Korea National Health and Nutrition Examination Survey

Background@#The risk of secondhand smoke (SHS) is gradually becoming apparent, and as smoking cessation zones are expanding, the exposure to SHS in workplaces, homes, and public places is decreasing. The objective of this study was to evaluate the actual exposure to SHS in nonsmokers. @*Methods@#This study used data from 2008 to 2011 and 2014 to 2018 from the Korean National Health and Nutrition Examination Survey (KNHANES). The urine cotinine concentration values were compared by the geometric mean according to sex, age group, and rurality for non-smokers aged 19 years or older who were tested for urine cotinine. @*Results@#The overall trend of urine cotinine concentration in Korean adult non-smokers have shown a decline since 2011. It gradually decreased from 2.82 ng/mL in 2010 to 0.50 ng/mL in 2016 but slightly increased to 0.79 ng/mL in 2018. Both male and female showed this trend. The decline tended to be lower in those aged 60 years and older, with higher urine cotinine concentrations in the recent 3 years in the rural than in urban residents. @*Conclusion@#The urinary cotinine concentration levels in Korean non-smokers increased from 2008 to 2010, then decreased till 2016, but gradually increased thereafter. This is possibly due to limiting the exposure to SHS through expanding the smoking area. Furthermore, a policy to lower the smoking rate with strict implementation and monitoring of the existing policy will be needed.

Application of Relative Fat Mass Equation in Korean Adults

Background@#Body mass index (BMI) has limitations in determining body fat percentage and body fat distribution, and causes misclassification of body fat-defined obesity. As high body fat percentage is associated with mortality, an accurate assessment of body fat percentage is considered clinically important. Recently, Woolcott and Bergman reported a relative fat mass (RFM) equation which calculated the body fat percentage using the height and waist circumferences. However, as RFM has been studied only in European-, Mexican-, and African-Americans, an assessment in Asians was needed. Therefore, we aimed to evaluate the applicability of RFM in Korean adults. @*Methods@#This study included 7,733 adults who visited a Sanggye Paik Hospital Health Promotion Center from May 1, 2016 to November 12, 2018. BMI and RFM were calculated by measuring height, weight, and waist circumference. The total body fat (TBF) percentage was measured by bioelectrical impedance analysis. We compared the BMI, RFM, and TBF percentage to assess the applicability of RFM in Korean adults. @*Results@#RFM had a statistically significant correlation with TBF percentage in both male and female (male: β=0.808, R2=0.653, female: β=0.766, R2=0.587, P<0.001). In the Bland-Altman plot, RFM showed good agreement with the TBF percentage within the 95% confidence interval. @*Conclusion@#The RFM equation can be used to predict TBF percentage in Korean adults.

The Relationship between Serum Uric Acid and Ankle Brachial Index in Korean Men

BACKGROUND: Elevated serum uric acid (UA) level is a known risk factor for atherosclerotic diseases, including peripheral arterial disease (PAD). PAD is easily diagnosed by determining the ankle-brachial index (ABI). The relationship between serum UA and subclinical atherosclerotic diseases remains controversial. We therefore aimed to explore an independent association between UA and ABI in healthy Korean men.METHODS: A cross-sectional study was conducted in 664 male participants aged ≥19 years who visited our Center for Health Promotion. The ABI and serum UA were determined for all participants and the relationship between these parameters and between ABI and other variables was assessed with the Pearson correlation coefficient. Multiple regression analysis was conducted to determine an independent correlation between serum UA and ABI after adjustment for certain variables. Analysis of covariance was employed to identify a trend in the ABI relative to UA quartiles.RESULTS: The ABI correlated inversely with UA and variables such as body mass index, diastolic blood pressure, heart rate, total cholesterol, triglycerides, and low-density lipoprotein-cholesterol. UA showed an independent inverse correlation with the ABI after serial adjustment for these variables (β=−0.265, P < 0.001). A decreasing trend in the ABI was observed with increasing UA quartile (P < 0.001).CONCLUSION: UA shows an independent inverse correlation with ABI in healthy Korean men.

Correlation between Serum Uric Acid and Carotid Intima-Media Thickness in Korean Women

BACKGROUND: Serum uric acid (UA) has been found to be associated with hypertension, obesity, dyslipidemia, and metabolic syndrome; however, its role as an independent risk factor of cardiovascular disease (CVD) is still controversial. There have been very few studies reporting an association between UA levels and carotid intima-media thickness (CIMT), especially in women.METHODS: The study included 245 subjects whose CIMT was evaluated between February 2016 and December 2017 at a health promotion center. We divided the population into two groups on the basis of menopausal status: premenopausal women (n=78) and postmenopausal women (n=167). We measured blood pressure, serum lipid profile, fasting blood glucose (FBG), and creatinine and UA levels. CIMT was measured using high-resolution B-mode ultrasonography.RESULTS: UA levels and CIMT were higher in postmenopausal women (P=0.029, P < 0.001). In premenopausal women, age (r=0.438), body mass index (r=0.373), UA (r=0.205), and FBG (r=0.336) were associated with CIMT, whereas in postmenopausal women, age (r=0.326), body mass index (r=0.167), UA (r=0.166), systolic blood pressure (r=0.200), and HDL-cholesterol (r=−0.140) were associated with CIMT. The UA level was independently associated with CIMT in premenopausal women (β=0.208, P=0.031), whereas age was the only factor independently associated with CIMT in postmenopausal women (β=0.253, P=0.002). Women in the highest tertile of uric acid level exhibited a higher CIMT than did those in the lowest tertile after age adjustment (P for trend < 0.001).CONCLUSION: UA may be an independent risk factor for CIMT, suggesting that UA is a risk factor for the early detection of CVD, especially in premenopausal women.

The Relationship Between Frequency of Injuries and Workplace Environment in Korea: Focus on Shift Work and Workplace Environmental Factors☆

BACKGROUND: The purpose of this study was to investigate the effect of shift work on occupational safety in various industrial sectors. The study analyzes the effects of shift work on the health of workers by considering factors such as the workplace environment and welfare. METHODS: Focusing on the 4(th) Korean Working Conditions Survey, this study used an ordinary least-square multiple regression analysis. The dependent variable was the annual frequency of injuries reported by workers. Independent variables were categorized as demographic, shift work, workplace environment, and welfare variables. The analysis was conducted on two levels: 1) Shift work and nonshift work groups were compared, and 2) Shift work was compared with fixed and rotating shifts. RESULTS: For the entire group, age, a low level of education, work hours, and daily and dispatch work negatively impacted the frequency of injuries. Shift work was negatively affected by workplace environment and welfare factors. In the shift group, the frequency of injuries was lower than that of regular workers, and the higher the autonomy in the choice of work hours, the lower the frequency of injuries. Furthermore, shift workers in Korea have more extended work hours (49.25 h/week) than other workers (46.34 h/week). CONCLUSION: Overall, welfare factors such as workplace satisfaction and work–life balance reduced the frequency of injuries. The effect of shift work was limited, but it was confirmed that shift worker autonomy could reduce the frequency of injuries.

Predictors of acute myocarditis in complicated scrub typhus: an endemic province in the Republic of Korea

BACKGROUND/AIMS: Scrub typhus is known as a self-limited infectious disease. Cardiac complication is uncommon and usually not life-threatening. Until now, few cases of fulminant myocarditis by scrub typhus have been reported. So, we investigated incidence and predictors of acute myocarditis in severe scrub typhus. METHODS: We retrospectively reviewed 89 patients among 91 scrub typhus confirmed patients who examined an echocardiogram and cardiac biomarkers from 2005 to 2015 in the intensive care unit at our hospital. We excluded two patients who didn’t have electrocardiography. Patients were divided into two groups and compared between scrub typhus with (n = 13) and without (n = 76) acute myocarditis. RESULTS: Age, sex, and underlying diseases were similar between the groups. The existence of eschar and duration of general ache and fever were similar between the groups. However, patients with acute myocarditis had more elevated total bilirubin, high incidence of ST elevations and paroxysmal atrial fibrillation (PAF) than those without acute myocarditis. Receiver operating characteristic analysis showed that the PAF was a predictor of myocarditis with a sensitivity of 70% and specificity of 84%. Predictive power of combination of ST-segment elevation and PAF was significantly associated with myocarditis in the multivariate analysis (odds ratio, 1.57; 95% confidence interval [CI], 1.21 to 11.7; p = 0.041) and area under the curve was 0.947 (95% CI, 0.878 to 0.983; p < 0.001). CONCLUSIONS: Acute myocarditis with scrub typhus may be more common than previously reported. Patients with high bilirubin and PAF are at increased risk of acute myocarditis with scrub typhus. These patients warrant closer follow-up and echocardiogram would be needed.

Martin's Equation as the Most Suitable Method for Estimation of Low-Density Lipoprotein Cholesterol Levels in Korean Adults / 가정의학회지

BACKGROUND: Friedewald equation is the most widely used method for estimating low-density lipoprotein cholesterol (LDL-C) level. However, due to potential over- or underestimation, many studies have used a modified equation. This study aimed to compare estimates by 4 different equations to directly measured LDL-C concentrations in order to propose the most appropriate method for LDL-C estimation in the Korean population. METHODS: We studied data of 4,350 subjects that included total cholesterol, high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), and LDL-C concentrations that had been measured at one university hospital in Seoul. We investigated 4 equations: LDL-C by Friedewald's original equation (LDL-C(F)) and its 3 modifications. Pearson correlation analysis was performed to compare these estimates to the direct measurement. RESULTS: Pearson correlation analysis revealed a good correlation among all 4 estimated LDL-C values and the directly measured LDL-C value. The Pearson coefficients were 0.951 for LDL-C(F), 0.917 for LDL-C by Hatta equation (LDL-C(H)), 0.968 for LDL-C by Puavilai equation (LDL-C(P)), and 0.983 for LDL-C by Martin equation (LDL-C(M)). Martin equation (LDL-C(M)) resulted in the best approximation (mean difference from the direct measurement, 5.5 mg/dL; mean percentage difference from the direct measurement, 5.1%) and the best agreement with the direct measurement (86.1%). LDL-C(P) resulted in the second-best approximation (mean difference, 7.0 mg/dL; mean percentage difference, 6.2%; concordance, 82.5%). LDL-C(M) was found to be less influenced by TG and HDL-C levels than by LDL-C(F). CONCLUSION: Estimates by Martin equation had the best agreement with direct LDL-C concentrations and both Martin and Puavilai equations were superior to Friedewald equation for estimating LDL-C concentrations in Korean adults.

Current Methods of Human Body Composition Assessment

The present study reviews recently developed and commonly used methods for determination of body composition in vivo with relevance for nutritional assessment. Body composition measurement methods are continuously being improved, with the most commonly used methods being bioelectrical impedance analysis, dual energy X-ray absorptiometry, computed tomography, and magnetic resonance imaging or magnetic resonance spectroscopy. Recent developments include three-dimensional photonic scanning, quantitative magnetic resonance, and air displacement plethysmography. Collectively, these techniques allow for the measurement of fat, fat-free mass, bone mineral content, total body water, extracellular water, total adipose tissue and its subdepots (visceral, subcutaneous, and intermuscular), skeletal muscle, select organs, and ectopic fat depots.

Treatment Effects of Ultrasound Guide Selective Nerve Root Block for Lower Cervical Radicular Pain: A Retrospective Study of 1-Year Follow-up

OBJECTIVE: To compare the long-term effects and advantages of ultrasound (US)-guided selective cervical nerve root block with fluoroscopy (FL)-guided transforaminal block. METHODS: From March 2009 to November 2012, 162 patients received steroid injections for lower cervical radicular pain. A total of 114 patients fulfilled the inclusion criteria. All procedures were performed by using US or FL. We compared the intravascular injections during the procedure with the effects and functional scales at 3, 6, and 12 months after the procedure between the two groups. Successful treatments occurred when patients obtained significant pain reliefs (as measured by >50% improvements in the verbal numerical scale [VNS] score and >40% improvements in the neck disability index [NDI] score) and reported a patient satisfaction score of 3 or 4 points at 12 months after the injection. Image analysis of intravascular injection and chart review were performed. Logistic regression was performed to reveal the correlations between successful treatments and variables (patient's age, gender, duration of the disease, cause, injection method, and radiologic finding). RESULTS: The VNS and NDI improved 3 months after the injection and continued to improve until 12 months for both groups. But there were no statistical differences in changes of VNS, NDI, and effectiveness between these two groups. The proportion of patients with successful treatment is illustrated as 62.5% in US-guided group and 58% in FL-guided group at 12 months. There were no significant differences between the groups or during follow-up periods. Three cases of the intravascular injections were done in FL-guided group. CONCLUSION: The US-guided selective cervical nerve root blocks are facilitated by identifying critical vessels at unexpected locations relative to the foramen and to protect injury to such vessels, which is the leading cause of reported complications from FL-guided transforaminal blocks. On treatment effect, significant long-term improvements in functions and pain reliefs were observed in both groups after the intervention. However, significant differences were not observed between the groups. Therefore, the US-guided selective cervical nerve root block was shown to be as effective as the FL-guided transforaminal block in pain reliefs and functional improvements, in addition to the absence of radiation and protection vessel injury at real-time imaging.