Representative Sample Of Korean Adults Research Articles

Oxidative balance scores in Korean adults are associated with periodontitis.

The Oxidative Balance Score (OBS) is a comprehensive metric that assesses the state of a person's oxidative balance. This study aimed to investigate the relationship between the oxidative balance score and moderate and severe periodontitis in a representative sample of Korean adults. Healthcare big data from the 7th Korea National Health and Nutrition Examination Survey (2016-2018) was used, and 16,489 adults aged ≥19years were included. Multivariate logistic regression analysis was performed to investigate the effect of sex-specific oxidative balance scores on periodontitis. In comparison with participants with a lower oxidative balance score, those with a higher oxidative balance score had a lower incidence of moderate and severe periodontitis (p<0.05). After adjusting for covariates, the oxidative balance score was negatively associated with moderate (odds ratio [OR]=0.952; 95% confidence interval [CI]: 0.934-0.971) and severe (OR=0.958; 95% CI: 0.931-0.986) periodontitis; however, the result was not significant for severe periodontitis in women's (OR=0.975; 95% CI: 0.934-1.018). Our study showed a statistically significant association between OBS and moderate and severe periodontitis, the small effect size should be interpreted with caution. The oxidative balance score was associated with moderate and severe periodontitis in Korean adults. Therefore, managing this score may help reduce the risk of periodontitis.

Associations between traumatic dental injuries due to violence and various drinking behaviors in Korea: A cross-sectional study.

Various patterns of alcohol consumption are associated with trauma and violence. The aim of this study was to assess the association between traumatic dental injuries (TDI) due to violence and different patterns of alcohol consumption in Korean adults. A cross-sectional study was conducted with representative sample of Korean adults. Among the total participants, 11.8% (6489/58,999) experienced TDI, and 0.9% (520/58,999) experienced TDI due to violence. The associations between various types of alcohol consumption (frequency of drinking, frequency of binge drinking, age of first drinking) and TDI due to violence were assessed using logistic regression analyses. We confirmed differences in the prevalence experience of TDI due to violence with various types of alcohol consumption by confounders (socioeconomic status). All types of drinking (frequency of drinking, frequency of binge drinking, age of first drinking) were strongly associated with TDI due to violence. After adjusting for confounders, those who started drinking at the age of 18 or younger and drank 4 or more days a week (OR: 2.86, 95% CI: 1.68-4.88), those who started drinking at the age of 18 or younger and drank 3 days or less a week (OR: 2.37, 95% CI: 1.40-4.02), and those who started drinking at the age of 18 or younger and binge drinking at least once a week (OR: 3.18, 95% CI: 1.79-5.65) had higher prevalence of TDI due to violence compared to those with no alcohol drinking. This study presents evidence of an association between various types of alcohol consumption and TDI due to violence in Korean adults. These findings suggest the necessity for policies aimed at reducing alcohol consumption, frequency of drinking, and access to drinking especially in adolescent to reduce the prevalence experience of TDI due to violence.

Longitudinal follow-up study of the association with gout and Alzheimer’s disease and Parkinson’s disease in Korea

To date, no clear conclusion on the relationships of gout with the occurrence of typical neurodegenerative diseases, Alzheimer’s disease (AD) and Parkinson’s disease (PD), has been reached. This study aimed to determine whether the patients with gout are at a lower or higher probability of developing AD or PD than those without gout. Longitudinal follow-up data of a representative sample of Korean adults were assessed. 18,079 individuals diagnosed with gout between 2003 and 2015 were enrolled in the gout group. The comparison group comprised 72,316 demographics-matched individuals not diagnosed with gout. Longitudinal associations of gout with AD or PD were estimated using Cox proportional hazard regression adjusting for potential confounders. The adjusted hazard ratios (HRs) of AD and PD in the gout group were 1.01 and 1.16 times higher than controls, but these differences were not statistically significant (95% confidence interval [CI] = 0.92–1.12 and 95% CI = 0.97–1.38, respectively). Although there was no significant association in the entire sample, AD and PD probabilities in patients with gout were significantly higher in participants < 60 years, and PD probabilities in patients with gout were significantly higher in overweight participants. Our findings identify significant correlations of gout with AD and PD in participants < 60 years and gout with PD in those with overweight, indicating that gout may play a role in the development of neurodegenerative diseases in younger or overweight populations. Further investigations should be performed to corroborate these findings.

Pro-inflammatory diet associated with low back pain in adults aged 50 and older

AimsTo investigate the association between pro-inflammatory diets and low back pain in a nationally representative sample of Korean adults. BackgroundLow back pain is one of the most common health issues. Evidence suggests a potential association between systemic inflammation and the development of low back pain, and the role of diet in mitigating the inflammation that, in turn, can alleviate low back pain. MethodsThis cross-sectional, correlational study used data from the 6th Korea National Health and Nutrition Examination Survey involving health interviews, examinations, and nutritional surveys. Dietary inflammatory index scores were generated based on 24-hour dietary recalls. Respondents were asked if they had experienced low back pain for at least 30 days in the past three months. Multiple logistic regression analyses were conducted to investigate the independent association between pro-inflammatory diets and low back pain. ResultsOf 7346 respondents, most participants were middle-aged, married, and non-/ex-smokers, lived in 2+ person households, consumed alcohol less than once a week, and had no allergies or underlying medical conditions. Respondents in the highest inflammatory diet quintile had nearly 0.25 higher odds of reporting low back pain than those in the lowest quintile (adjusted ORquintile5vs1: 1.25, 95%CI [1.01–1.54]; p = .043). ConclusionsResults from this study indicate a role of pro-inflammatory diets in the development of low back pain. Nurses can screen for those consuming pro-inflammatory foods, and thus, are vulnerable to back pain, and aid in the delivery of tailored nutritional education. Future studies should investigate how diet affects low back pain diagnosis and chronicity relative to pain phenotypes.

Body mass index and self-rated oral health in Korean adults in 2017.

To investigate the association between obesity and self-rated oral health (SROH). This study examined the cross-sectional associations between body mass index (BMI) and SROH in Korean adults. This study used data from 217304 adults (100110 men and 117194 women aged>19years) from the 2017 Korean Community Health Survey. Participants were categorised into six ordinal groups based on BMI: underweight (<18.5kg/m2 ), normal weight (18.5-22.9kg/m2 ), overweight (23.0-24.9kg/m2 ), obese-I (25.0-27.4kg/m2 ), obese-II (27.5-29.9kg/m2 ) or obese-III (≥30.0kg/m2 ). SROH was assessed using responses to the question, "How do you rate your oral health, including your teeth and gums?" rated on a 5-point scale. SROH was categorised as "good" (reported as "fair," "good" or "very good") or "poor" or "very poor." Age- and sex-stratified associations between BMI categories and poor SROH were assessed using ordinal logistic regression analysis with sampling weights. The age-adjusted odds ratio (OR) for poor SROH according to BMI levels was lowest in the overweight group in both men and women. In men, the OR for poor SROH was 2.03 (99% confidence interval [CI], 1.72-2.39) in the underweight group, 1.17 (99% CI, 1.17-1.25) in the normal group, 1.05 (99% CI, 0.98-1.13) in the obese-I group, 1.08 (99% CI, 0.98-1.18) in the obese-II group and 1.36 (99% CI, 1.20-1.55) in the obese-III group. In women, the OR was 1.18 (99% CI, 1.07-1.31) in the underweight group, 1.01 (99% CI, 0.95-1.07) in the normal group, 1.07(99% CI, 0.99-1.16) in the obese-I group, 1.16 (99% CI, 1.04-1.30) in the obese-II group and 1.39 (99% CI, 1.20-1.62) in the obese-III group. From the restricted cubic spline models in both sexes, BMI showed a J-shaped association with poor and very poor SROH in men and women. In a stratified analysis by age group and sex, men and older women in the underweight group had poorer SROH than those in overweight group. In a nationally representative sample of Korean adults, there was a J-shaped association between BMI and poor SROH, with the highest risk in the underweight group amongst men and in the obese-III group amongst women. Furthermore, in men and women over 65years of age, underweight and obesity were associated with poorer SROH.

Multimorbidity and Health-Related Quality of Life in Korean Older Adults: A Mediation Analysis on Handgrip Strength

Background: The influence of handgrip strength on the relationship of multimorbidity with health-related quality of life (HRQoL) is unknown in geriatric populations. The current study investigated whether or not handgrip strength mediates the association between multimorbidity and HRQoL in a representative sample of Korean adults (3139 men/3753 women) aged 65 years and older. Methods: The data obtained from the 2014–2019 Korea National Health and Nutrition Examination Survey (KNHNES) were used in the current study. The EuroQoL group was used to assess HRQoL. Multimorbidity was defined as co-existence of more than one of the 26 diagnosed diseases specified in the KNHNES. A digital hand dynamometer was used to measure handgrip strength. The covariates included in this study were age, gender, parameters of body fatness, socio-demographics, and parameters of health behaviors. Results: Analysis of variance showed that HRQoL was inversely associated with number of chronic conditions and positively with relative handgrip strength. Particularly, a mediation analysis using the PROCESS macro in SPSS-PC showed that relative handgrip strength partially mediates the influence of multimorbidity on HRQoL. Bootstrapping showed that the indirect effect of comorbidity on HRQoL via relative handgrip strength was significant (p &lt; 0.001) even after adjustments for all the covariates, explaining 8.1% the total effect. Conclusions: The findings of the study emphasize the importance of health-related physical fitness while managing and/or treating multiple chronic conditions for better HRQoL in geriatric populations.

Solitary and Social Drinking in South Korea: An Exploratory Study.

ObjectivesThis study aimed to identify differences in drinking norms, heavy drinking, and motives between types of drinkers (abstainers, solitary, and social drinkers) in a representative sample of Korean adults.MethodsAn online survey of people registered on the electoral roll were randomly invited to be part of the “National Korean Drinking Culture Study” conducted in 2018 (n = 3,015). Participants included 1,532 men and 1,469 women aged 19–60 years. Questions included the number of times they drank in the last month, what they drank, and the volume drank. The amount of pure alcohol consumed was calculated. Drinking norms, motives, and types were determined in the survey questions.ResultsSolitary drinkers were more likely to be divorced or separated, less educated, and marginally employed. Solitary drinking peaked in those in their 30s (18.5%) and social drinkers in their 50s (68.1%). Solitary drinkers drank more frequently compared with social drinkers (6.1 vs. 3.6 times per month, p < 0.001), and consumed a significantly larger quantity of alcohol (69.5 g vs. 46.8 g per week). Solitary drinkers were more accepting of drinking-related behaviors in diverse situations compared with social drinkers. The regression analysis revealed that personal drinking motives were the most important factor influencing the frequency and quantity of alcohol consumption in both solitary and social drinking.ConclusionSolitary drinkers may be more vulnerable to alcohol abuse than social drinkers.

Association of Body Mass Index and Waist Circumference with All-Cause Mortality in Hemodialysis Patients.

In this study based on a large nationally representative sample of Korean adults, we investigated the potential associations of the body mass index (BMI) and waist circumference (WC) with mortality in patients undergoing hemodialysis. We obtained the data of 18,699 participants >20 years of age who were followed up with for 4 years and for whom BMI and WC information were available, using a nationally representative dataset from the Korean National Health Insurance System. Patients were stratified into five levels by their baseline BMI and into six levels by their WC (5-cm increments). A total of 4975 deaths occurred during a median follow-up period of 48.2 months. Participants with a higher BMI had a lower mortality rate than those with a lower BMI. In a fully adjusted Cox regression analysis, being overweight and obese was associated with a significantly lower relative risk of all-cause mortality relative to the reference group. Conversely, the mortality rate was higher among participants with a high WC than among those with a low WC. Participants with the highest WC had a higher risk of mortality, while those with the lowest WC level had a significantly lower risk of mortality. In conclusion, all-cause mortality was positively associated with WC, a measure of abdominal obesity, and inversely associated with BMI, a measure of body volume, in patients undergoing hemodialysis.

Non-exercise based estimation of cardiorespiratory fitness is inversely associated with metabolic syndrome in a representative sample of Korean adults

BackgroundThis study investigated the association between non-exercise based estimation of cardiorespiratory fitness (eCRF) and metabolic syndrome (Mets) in Korean adults aged 18 years and older (13,400 women and 9885 men).MethodsData from the 2008 and 2011 Korea National Health and Nutrition Examination Surveys IV and V in South Korea were analyzed. eCRF was assessed with a previously validated procedure. Participants were classified into 5 categories from the lowest quantile to the highest quantile based on individual eCRF distributions.ResultsThe findings showed an independent and inverse association between eCRF and Mets in women and men separately. Individuals in the highest eCRF category (quantile 5) had a significantly lower prevalence of Mets (14.5 and 14.8% for women and men, respectively) compared with their counterparts (40.4 and 46.4% for women and men, respectively) in the lowest eCRF category (quantile 1), and the association showed a graded response, with the quantiles 2, 3, and 4 also significantly associated with a lower prevalence of Mets compared with the quantile 1. Furthermore, the prevalence of Mets in the highest quantile compared with the lowest quantile remained statistically significant in both men (p < 0.05) and women (p < 0.05) even after adjustments for age, body mass index, skeletal muscle index, smoking, heavy drinking, vitamin D, caloric intake, and dietary intakes of carbohydrates, fats, and proteins.ConclusionThe findings support a preventive role for eCRF against Mets in Korean adults.

Factors affecting awareness of preparedness after moderate earthquakes

PurposeThe purpose of this paper is to examine how experiencing moderate earthquakes influences risk perception and preparedness.Design/methodology/approachAn online survey was conducted on a nationally representative sample of Korean adults after the moderate earthquake in Pohang in 2017. Statistical analyses were conducted to identify the determinants of willingness to pay (WTP) for seismic retrofitting and earthquake insurance.FindingsThe results show that risk perception, housing ownership, earthquake experience and income level significantly influenced WTP for seismic retrofitting and earthquake insurance. The results also indicate that a greater number of damage-free earthquake experiences reduced the WTP that could be explained by normalcy bias. Finally, people who believed that the Pohang earthquake might be an example of induced seismicity (i.e. triggered by the geothermal power plant) tended to have a lower WTP for seismic retrofitting.Originality/valueThis study offers valuable findings on public attitudes about enhancing earthquake preparedness policies in moderate earthquake zones, regions that few studies have examined despite their high vulnerability due to a lack of preparedness.

Association between Body Mass Index and Prevalence of Asthma in Korean Adults.

We evaluated the association between body mass index (BMI) and the prevalence of asthma. Using data from the 2015 Korean Community Health Survey, 214,971 participants aged between 19 and 106 years were included in this study. Asthma was defined based on the self-report of physician diagnosis. BMI was classified as underweight (<18.5 kg/m2), normal weight (18.5 kg/m2≤BMI<23.0 kg/m2), overweight (23.0 kg/m2≤ BMI<27.4 kg/m2), and obese (≥27.5 kg/m2) based on the BMI categories for Asians by the World Health Organization. Multiple logistic regression analysis was performed with sampling weights to evaluate the association between BMI and asthma after adjusting for age, educational level, income, type of residential area, smoking status, alcohol consumption, physical activity, hypertension, and diabetes. In men, BMI had an inverted J-shaped association with the prevalence of asthma, with an odds ratio of 1.88 (95% confidence interval [CI]: 1.89–2.24) for underweight and 1.12 (95% CIs: 0.97–1.29) for obesity. In women, BMI had a J-shaped association with the prevalence of asthma, with an odds ratio of 1.05 (95% CIs: 0.91–1.22) for underweight and 2.29 (95% CIs: 2.06–2.56) for obesity. In conclusion, in a nationally representative sample of Korean adults, the association between BMI and the prevalence of asthma varied between the sexes. This suggests that malnutrition and obesity are involved in the pathophysiology of asthma.

Blood Lead Concentrations and Mortality in Korean Adults

PDS 63: Chemicals and metals: health effects, Exhibition Hall (PDS), Ground floor, August 27, 2019, 10:30 AM - 12:00 PM Background/Aim: Previous studies have reported an increased risk of mortality at high blood lead level. In Korea, the association between blood lead and mortality has not been investigated. While food is the major source of human exposure to lead and dietary pattern can be related to health, to best our knowledge, none of the previous studies have considered food intake as a potential confounder. Thus, we aimed to examine the association of mortality with blood lead for Korean adults considering lead-contaminated food intake. Methods: From 2008-2013 KNHANES-linked mortality data which are followed through December 2016, we used 7,939 participants (46,990 person-years) who aged over 30 at the time of examination. We estimated the relative hazard of mortality from all-cause, circulatory diseases, and cancer through Cox-proportional hazard regression adjusted for potential confounders. Intake of grains, vegetables, and seafood calculated from dietary 24hr-recall data was additionally adjusted. Results: Blood lead levels tended to increase as intake of grains, vegetables, and seafood increased. The natural log unit increase of blood lead levels was associated with an increase of all-cause (HR: 1.67, 95% CI: 1.11-2.53), circulatory diseases (HR: 2.84, 95% CI: 1.13-7.13), and cancer (HR: 1.77, 95% CI: 1.02, 3.08) mortality. Further adjustment of lead-contaminated food intake slightly increased the magnitude of the associations: all-cause (HR: 1.72, 95% CI: 1.14-2.60); circulatory diseases (HR: 3.02, 95% CI: 1.25-7.29); cancer (HR: 1.74, 95% CI: 0.98, 3.10). Conclusions: We found that blood lead concentration was significantly associated with mortality in a representative sample of Korean adults, which is consistent results with previous studies. Lead-contaminated food intake is suspected to be a negative confounder as high consumption of grains, vegetables, and seafood is likely to be associated with a reduction in mortality.

269. Is regular walking associated with a lower risk of low back pain? A cross-sectional study using the Korean National Health and Nutrition Examination surveys

BACKGROUND CONTEXT Physical activity, such as muscle strengthening and aerobic exercise, has been found to be effective for low back pain (LBP). However, the association between weekly walking duration and LBP in the general population remains poorly understood. PURPOSE This study aimed (1) to analyze the association between walking and LBP and (2) to examine this association according to walking duration and overall walking days per week in a general population over 50 years of age using a representative sample of Korean adults. STUDY DESIGN/SETTING Cross-sectional study. PATIENT SAMPLE Data from the Korea National Health and Nutrition Examination Surveys V and VI, performed from 2010 to 2015. OUTCOME MEASURES Multiple logistic regression analysis was performed to determine the association between walking days and duration and LBP. Analysis was restricted to participants aged over 50 years who responded to surveys on LBP and walking activity. METHODS National health and nutrition examination surveys were performed in the Korean general population (n = 48,482) from 2010 to 2015. LBP status was surveyed using a self-reported questionnaire form (“Have you complained of LBP for more than 30 days during the past 3 months?”). Daily walking activity (low-intensity activity) was evaluated using the following two questions: (1) “During the last 7 days, on how many days did you walk for at least 10 minutes at a time? This includes at work and at home, walking to travel from place to place, and any other walking that you have done solely for recreation, sport, exercise, or leisure.” (2) “How much time did you usually spend walking on each of those days?” Walking duration per day was classified into two categories: over 30 min/day and over 1 h/day. Overall walking days per week were categorized into RESULTS Walking for more than 3 days per week for over 30 min at a time was negatively associated with LBP in the unadjusted (adjusted odds ratio [aOR]: 0.65, P CONCLUSIONS Our study showed that longer walking duration was associated with a lower risk of LBP using a cross-sectional health survey in the Korean general population.Regular walking with a longer duration for more than 3 days/week is significantly associated with a lower risk of LBP in the general population aged over 50 years. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

The association between periodontitis and dyslipidemia according to smoking and harmful alcohol use in a representative sample of Korean adults

The aim of this study was to examine whether dyslipidemia is associated with periodontitis according to age, sex, smoking, and harmful alcohol use in a representative sample of Korean adults who participated in the Sixth Korea National Health and Nutrition Examination Survey (KNHANES VI-3). We examined 3987 subjects aged 19 to 79years who participated in the KNHANES VI-3. Dyslipidemia was defined according to the definition proposed by the Korean Society of Lipidology and Atherosclerosis. The periodontal status of the patients was assessed using the community periodontal index. Multivariate logistic regression analysis was carried out and adjusted for sociodemographic variables, oral and general health behaviors, and oral health status. All analyses considered a complex sampling design, and multivariate analysis was performed in the age, sex, smoking, and harmful alcohol use subgroups. Multivariate logistic regression analysis revealed significant associations between periodontitis and dyslipidemia including hypertriglyceridemia and hypo-high-density lipoprotein (HDL) cholesterolemia. In the subgroup analysis, periodontitis was significantly associated with hypo-HDL cholesterolemia in subjects older than 40 years, males, heavy smokers, and hazardous and harmful alcohol users. Moreover, periodontitis was significantly associated with hypercholesterolemia in hazardous and harmful alcohol users. The prevalence of periodontitis (CPI 3, 20.7%; CPI 4, 9.0%) was 29.7% in Korea. Hyper-TG and hypo-HDL-C were associated with periodontitis in all subjects. In the subgroup analysis, the association of periodontitis with hyper-TC and pre-hyper-TC was further confirmed in harmful alcohol users and males, respectively. This study reaffirmed that periodontitis is associated with dyslipidemia, especially with hyper-TG and hypo-HDL-C. As the association of periodontitis with hypo-HDL-C, hyper-TC, and pre-hyper-TC was found differently in subgroups according to age, gender, smoking, and alcohol drinking, researchers need to consider effect modifiers in further studies on the association between periodontitis and dyslipidemia.

Dose-Dependent Toxic Effect of Cotinine-Verified Tobacco Smoking on Systemic Inflammation in Apparently Healthy Men and Women: A Nationwide Population-Based Study.

Chronic exposure to tobacco smoke leads to chronic low-grade systemic inflammation; however, little is known about the dose-dependent toxic effect of objective tobacco smoking on systemic inflammation. We examined the dose-dependent toxic effect of cotinine-verified tobacco smoking on leukocyte count in a representative sample of Korean adults, including 8655 men and 10,432 women aged 19–65 years from the Korean National Health and Nutrition Examination Survey. The participants were categorized into five groups by the level of urine cotinine (Ucot) as follows: A non-smoker group (<50.00 ng/mL) and four quartile groups for smokers for both men and women. The odds ratios (ORs) and 95% confidence intervals (CIs) for sex-specific high leukocyte count (≥75th percentile) were calculated across five groups of Ucot concentrations using multiple logistic regression analyses. The mean values of leukocyte count gradually increased according to the grade of Ucot concentration in both sexes. The ORs (95% CIs) for high leukocyte count in the 4th Ucot quartile concentrations versus the non-smokers were 4.09 (3.39–4.94) for men and 3.91 (2.82–5.41) for women after adjusting for confounding variables. The present study confirmed the dose-response toxic effect of tobacco smoking on chronic low-grade systemic inflammation.

The fatty liver index, a simple and useful predictor of metabolic syndrome: analysis of the Korea National Health and Nutrition Examination Survey 2010-2011.

PurposeNonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide, and it is the hepatic manifestation of metabolic syndrome (MetS). We aimed to estimate the prevalence of NAFLD defined by the fatty liver index (FLI), in order to investigate the association between FLI and metabolic disorders and to determine the cutoff value of FLI to screen for MetS.Subjects and methodsThis study utilized a national representative sample of Korean adults (the Korean National Health and Nutrition Examination Surveys) which was conducted in 2010–2011. A total of 10,107 adults aged 19 years or older were selected. NAFLD was diagnosed on the basis of an increased FLI (≥60) after the exclusion of alcohol or viral liver disease.ResultsNAFLD was identified in 1,134 subjects (age-standardized prevalence, 10.0%). When subjects were categorized into three groups by FLI (<20, 20–59, and ≥60), the higher FLI group showed a higher prevalence of hypertension (49.7% vs 14.4%), diabetes mellitus (DM; 20.4% vs 3.8%), and MetS (74.9% vs 7.4%). FLI was positively associated with age, body mass index, blood pressure, hemoglobin A1c, and homeostasis model assessment of insulin resistance (P for trend <0.001). In the multivariate analysis, the higher FLI group had a significantly higher risk for hypertension (OR =2.92, 95% CI =2.18–3.90, P<0.001), DM (OR =4.38, 95% CI =2.96–6.49, P<0.001), and MetS (OR =24.85, 95% CI =17.33–35.64, P<0.001). However, no increase was observed for cardiovascular disease after adjustment of other risk factors. The cutoff value of the FLI estimated to predict the presence of MetS was 20 (area under the curve 0.849, sensitivity 0.828, and negative predictive value 91.9%).ConclusionNAFLD prevalence using FLI is significantly higher in subjects with metabolic disorder including MetS. FLI might be a useful screening tool to detect subjects who may require early management of MetS and who have a high cardiovascular risk.

Association between pterygium, sun exposure, and serum 25-hydroxyvitamin in a nationally representative sample of Korean adults

PurposeUltraviolet-B (UVB) light exposure is the major risk factor for developing a pterygium, and serum 25-hydroxyvitamin D (25(OH)D) level is an objective measure of UVB light exposure. In this study, we investigated the association between pterygium, sun exposure, and serum 25(OH)D.MethodsThis population-based, cross-sectional study comprised 12,258 adults (aged ≥19 years) participating in the fifth annual Korea National Health and Nutrition Examination Survey from 2010 to 2012. The enrolled subjects underwent interviews, clinical examinations, and laboratory investigations. The serum 25(OH)D levels were measured, and pterygium was examined by using a slit lamp. We used three adjusted logistic regression models and selected covariates as potential confounders.ResultsThe overall prevalence of pterygium was 7.09, and 53.1% of these subjects were women. The prevalence of pterygium was higher in elderly subjects and those who lived at low latitudes. In multivariate analysis with adjustment for confounding factors, subjects with a serum 25(OH)D level > 30 ng/mL, 25–30 ng/mL, and 15–20 ng/mL had an odds ratio (OR) (95% confidence interval [CI]) of 1.565 (1.035–2.366), 1.545 (1.086–2.198), 1.8 (1.358–2.386), and 1.535 (1.216–1.938), respectively, compared to those with a serum 25(OH)D level < 15 ng/mL. Subjects with a daily sun exposure > 5 h had an OR (95% CI) of 1.761 (1.395–2.223) compared to subjects with a daily sun exposure < 2 h.ConclusionThe present study provides epidemiological evidence of an association of daily sun exposure and serum 25(OH)D levels with pterygium in a representative Korean population.

Walking more than 90minutes/week was associated with a lower risk of self-reported low back pain in persons over 50years of age: a cross-sectional study using the Korean National Health and Nutrition Examination Surveys

BACKGROUND CONTEXTPhysical activity, such as muscle strengthening and aerobic exercise, has been found to be effective for low back pain (LBP). However, the association between weekly walking duration and LBP in the general population remains poorly understood. OBJECTThis study aimed (1) to analyze the association between walking and LBP and (2) to examine this association according to walking duration and overall walking days per week in a general population over 50years of age using a representative sample of Korean adults. STUDY DESIGNCross-sectional study. PATIENT SAMPLEData from the Korea National Health and Nutrition Examination Surveys V and VI, performed from 2010 to 2015. OUTCOME MEASURESMultiple logistic regression analysis was performed to determine the association between walking days and duration and LBP. Analysis was restricted to participants aged over 50years who responded to surveys on LBP and walking activity. METHODSNational health and nutrition examination surveys were performed in the Korean general population (N=48,482) from 2010 to 2015. LBP status was surveyed using a self-reported questionnaire form (“Have you complained of LBP for more than 30days during the past 3 months?”). Daily walking activity (low-intensity activity) was evaluated using the following two questions: (1) “During the last 7days, on how many days did you walk for at least 10 minutes at a time? This includes at work and at home, walking to travel from place to place, and any other walking that you have done solely for recreation, sport, exercise, or leisure.” (2) “How much time did you usually spend walking on each of those days?” Walking duration per day was classified into two categories: over 30min/day and over 1h/day. Overall walking days per week were categorized into <3, 3–4, and ≥5days/week. Basic characteristics, comorbidities, socioeconomic status, and other variables were used to create multiple logistic regression models. No sources of funding and no conflicts of interest were associated with this study. RESULTSWalking for more than 3days per week for over 30 minutes at a time was negatively associated with LBP in the unadjusted (adjusted odds ratio [aOR]: 0.65, p<.001) and fully adjusted logistic regression models (aOR: 0.79, p<.001). Similarly, walking for more than 5days per week for over 1 hour at a time was negatively associated with LBP in the unadjusted (aOR: 0.62, p<.001) and fully adjusted logistic regression models (aOR: 0.76, p<.001). The risk of LBP decreased with increasing walking days and duration. CONCLUSIONSOur study showed that longer walking duration was associated with a lower risk of LBP using a cross-sectional health survey in the Korean general population. Regular walking with a longer duration for more than 3days/week is significantly associated with a lower risk of LBP in the general population aged over 50years.

The prevalence of and factors associated with urinary cotinine-verified smoking in Korean adults: The 2008-2011 Korea National Health and Nutrition Examination Survey.

BackgroundSmoking rate based on self-reporting questionnaire might be underestimated. Cotinine is the principal metabolite of nicotine and is considered an accurate biomarker of exposure to cigarette smoke.ObjectivesThis study evaluated the prevalence of and factors associated with urinary cotinine-verified smoking in Korean adults.MethodsWe analyzed data from 12,110 adults in the 2008–2011 Korea National Health and Nutrition Examination Survey (KNHANES), using three threshold levels of urinary cotinine ≥100ng/ml, ≥50ng/ml, and ≥30ng/ml.ResultsThe weighted prevalence of urinary cotinine levels of ≥100, ≥50, and ≥30 ng/mL in the whole study population was 34.7%, 37.1%, and 41.1%, respectively. Male sex, younger age, elementary school graduation, household income in the ≤24th percentile, service and sales workers and assembly workers, and high-risk alcohol drinking were associated with a higher prevalence of urinary cotinine level of ≥ 50 or 30 ng/mL, after we adjusted for age, sex, education level, number of family members, household income, occupation, and alcohol drinking.Logistic regression analyses were performed using the aforementioned variables as covariates to identify factors independently associated with cotinine-verified smoking. Men had a higher risk than women of having a urinary cotinine level of ≥50 ng/mL (OR 4.67, 95% CI 4.09–5.32, p < 0.001). When subjects ages 19–29 years were used as controls, adults ages 30–39 years had a 1.19-fold (CI 1.02–1.39, p = 0.026) higher risk of having a urinary cotinine level of ≥50 ng/mL. College graduates had a 32% lower risk of having a urinary cotinine level of ≥50 ng/mL than elementary school graduates (p < 0.001).A household income in the 25–49th percentile (OR 0.82, 95% CI 0.69–0.98, p = 0.026), 50–74th percentile (OR 0.64, 95% CI 0.53–0.76, p < 0.001), or ≥75th percentile (OR 0.64, 95% CI 0.53–0.77, p < 0.001) was associated with a lower risk of having a urinary cotinine level of ≥50 ng/mL compared to a household income in the ≤24th percentile. High-risk (OR 2.75, 95% CI 2.37–3.18, p < 0.001) and intermediate-risk (OR 2.04, 95% CI 1.82–2.30, p < 0.001) alcohol drinking were associated with having a urinary cotinine level of ≥50 ng/mL compared to low-risk alcohol drinking. Similar to the results of the logistic regression analyses of urinary cotinine ≥50 ng/mL, male sex, younger age, elementary school education, household income in the ≤24th percentile, and high-risk alcohol drinking were significantly associated with having a urinary cotinine level of ≥30 ng/mL. Service and sales workers (OR 1.22, 95% CI 1.01–1.48, p = 0.041) had a significantly higher risk of having a urinary cotinine level of ≥30 ng/mL.ConclusionsBased on a threshold urinary cotinine level of 50 ng/mL, the prevalence of cotinine-verified smoking in a representative sample of Korean adults was 37.1% (men 52.7%, women 15.4%). Younger age, male sex, low education level, service and sales workers, low household income, and high-risk alcohol drinking were associated with the risk of smoking.

The Cardiometabolic Burden of Self-Perceived Obesity: A Multilevel Analysis of a Nationally Representative Sample of Korean Adults

Emerging evidence has shown that self-perception of overweight/obese status is associated with unfavorable cardiometabolic outcomes, above and beyond actual body weight. Given the lack of research among Asian populations, we examined the association between weight perception and metabolic syndrome (MetS) and cardiometabolic risks among Koreans. Data from the 2010–2015 Korea National Health and Nutrition Examination Survey, including women (N = 12,181) and men (N = 9,448) aged 19–65 years, were analyzed. Weight status perception was measured by participants’ self-evaluation of their body size (“very/slightly obese,” “normal,” and “very/slightly thin”). Overall, 23.2% of women and 28.7% of men had MetS. Our cross-sectional multilevel logistic analyses showed a significant positive association between self-perceived obesity (vs. perceived normal weight) and MetS, independent of BMI and sociodemographic/behavioral/medical conditions, with a stronger association detected among men (OR = 1.38, p < 0.05) than women (OR = 1.22, p < 0.05), confirmed by a statistically significant interaction. Additionally, perceived obesity was associated with high blood pressure (OR = 1.27, p < 0.05) and high triglycerides (OR = 1.38, p < 0.05) among men and low high-density lipoprotein cholesterol (OR = 1.15, p < 0.05) among women. While further prospective research is needed, our findings suggest that perception of being obese may be an unfavorable indicator of cardiometabolic health among Koreans regardless of actual body weight.