confounding variables.RESULTS: The BMD of the total femur and Ward's triangle were significantly different according to the potassium intake among men (P = 0.031 and P = 0.010, respectively). Women in the top tertile for potassium intake showed higher BMD than those in the bottom tertile at all measurement sites (all P < 0.05). Daily potassium intake was significantly related to a decreased risk of osteoporosis at the lumbar spine in postmenopausal women (odds ratios: 0.68, 95% confidence interval: 0.48-0.96, P trend = 0.031). However, the dietary potassium level was not related to the risk of osteoporosis in men.CONCLUSION: Current findings indicate that higher dietary potassium levels have a favorable effect on bone health and preventing osteoporosis in older Korean women.]]>
Absorptiometry, Photon ; Adult ; Bone Density ; Bone Diseases, Metabolic ; Calcium ; Confounding Factors (Epidemiology) ; Cross-Sectional Studies ; Epidemiology ; Female ; Femur ; Femur Neck ; Hip ; Humans ; Logistic Models ; Male ; Methods ; Nutrition Surveys ; Osteoporosis ; Population Surveillance ; Potassium ; Potassium, Dietary ; Prevalence ; Retrospective Studies ; Spine ; Vitamin D

OBJECTIVES: The purpose of this study was to investigate the association between the components of metabolic syndrome (MetS) (waist circumference, hyperglycemia, hypertriglyceridemia, low levels of high-density lipoprotein cholesterol, and hypertension) and periodontitis in Korean adults aged 35–79 years. METHODS: In this study, data from the Sixth Korean National Health and Nutrition Examination Survey (KNHANES, 2013–2015) were analyzed. Among the 22,948 participants of the Sixth KNHANES, 8,314 participants, who were aged 35–79 years and had completed all systemic and oral health examinations and questionnaires, were included in this study. Confounding variables associated with the demographics and socioeconomic status and systemic and oral health-related behaviors were age, gender, household income, the educational level, smoking and drinking habits, the physical activity status, and frequency of daily toothbrushing. The independent variables were components of MetS, and the dependent variable was periodontitis. RESULTS: Periodontitis was diagnosed in 37.0% of the participants. The incidence of periodontitis among participants with MetS was 47.9%. The incidences of periodontitis among participants with three, four, and five components of MetS were 44.8%, 50.0%, and 56.2%, respectively. The odds ratio (OR) for periodontitis among participants with MetS was 1.43 (95% confidence interval [CI]: 1.27–1.61). The participants with three, four, and five components of MetS showed a significantly higher OR for periodontitis than those with no components of MetS (three components, OR=1.18, 95% CI: 1.02–1.36; four components, OR=1.34, 95% CI: 1.14–1.59; five components, OR=1.68, 95% CI: 1.29–2.20). CONCLUSIONS: A higher number of components of MetS augments the OR of periodontitis.
Adult ; Cholesterol ; Confounding Factors (Epidemiology) ; Demography ; Drinking ; Epidemiology ; Family Characteristics ; Humans ; Hyperglycemia ; Hypertriglyceridemia ; Incidence ; Lipoproteins ; Motor Activity ; Nutrition Surveys ; Odds Ratio ; Oral Health ; Periodontitis ; Smoke ; Smoking ; Social Class ; Toothbrushing

BACKGROUND: Several studies have suggested that breastfeeding has a positive effect on long-term obesity, diabetes, hypertension, and hyperlipidemia. This study aimed to examine maternal bone health, muscle mass, and obesity based on breastfeeding duration. METHODS: This study was based on the Korea National Health and Nutrition Examination Survey 2010–2011. We selected 2,027 elderly women by screening survey participants with a history of delivery. Multivariate logistic regression analyses were performed to estimate the odds ratios (ORs) of sarcopenia, osteoporosis, and obesity among four breastfeeding groups. RESULTS: The OR of sarcopenia significantly decreased with increasing breastfeeding duration (OR, 0.27; 95% confidence interval [CI], 0.11–0.65; P for trend <0.001), whereas the OR of obesity significantly increased with increasing breastfeeding duration (OR, 2.56; 95% CI, 1.43–4.60; P for trend=0.009) after adjusting for potential confounding variables. We also found a positive correlation between the duration since last delivery and sarcopenia. CONCLUSION: Our results suggest a negative correlation between prolonged breastfeeding and the prevalence of sarcopenia, and a positive correlation between prolonged breastfeeding and the prevalence of obesity. Further studies are needed to clarify the relationship between breastfeeding and sarcopenia in the future.
Aged ; Breast Feeding ; Confounding Factors (Epidemiology) ; Cross-Sectional Studies ; Female ; Humans ; Hyperlipidemias ; Hypertension ; Korea ; Logistic Models ; Mass Screening ; Nutrition Surveys ; Obesity ; Odds Ratio ; Osteoporosis ; Prevalence ; Sarcopenia

BACKGROUND: Cigarette smoking increases the risk of atherosclerosis, which often develops as vascular calcification on radiologic examinations. This study evaluated the relationship between smoking-related factors and incidental abdominal aorta calcification (AAC) detected by computed tomography (CT) among middle-aged and elderly men. METHODS: We assessed the abdominal CT findings of 218 men aged 40 to 81 years who underwent health checkups. The associations between smoking factors and AAC were analyzed using logistic regression analysis to adjust for confounding variables such as age, lifestyle factors, and chronic diseases. RESULTS: Adjusting for confounding variables, the risk of AAC was significantly increased in association with smoking for at least 20 years (adjusted odds ratio [AOR], 5.22; 95% confidence interval [CI], 1.82–14.93), smoking 10+ pack-years (10–20 pack-years: AOR, 4.54; 95% CI, 1.07–5.68; >20 pack-years: AOR, 5.28; 95% CI, 2.10–13.31), and a history of smoking (former smoker: AOR, 2.10; 95% CI, 1.07–5.68; current smoker: AOR, 5.05; 95% CI, 2.08–12.26). In terms of the daily smoking amount, even a low smoking level increased the risk of AAC. CONCLUSION: These findings suggest that smoking for 20+ years, smoking 10+ pack-years, and even a low level of smoking daily increases the likelihood of developing AAC. Clinicians should recommend that patients quit smoking and stress the importance of smoking duration when promoting health in middle-aged and elderly patients.
Aged ; Aorta, Abdominal ; Atherosclerosis ; Chronic Disease ; Confounding Factors (Epidemiology) ; Humans ; Life Style ; Logistic Models ; Male ; Odds Ratio ; Smoke ; Smoking ; Tomography, X-Ray Computed ; Vascular Calcification

BACKGROUND: Cancer survivors are at a higher risk of primary cancer recurrence and development of second primary cancer. In both cases, early disease detection is crucial. This cross-sectional study assessed cancer screening participation rates according to cancer history. METHODS: Data were obtained from the 2010–2012 Korea National Health and Nutrition Examination Survey for 12,500 participants. Of these, 624 cancer survivors were enrolled in this study. Sampling weights were applied to maintain the representativeness of the Korean adult population. RESULTS: Overall 2-year cancer screening rates prior to the survey in male and female cancer survivors were 59.9% and 73.7%, respectively, while opportunistic cancer screening rates were 33.5% and 52.1%, respectively. The odds ratios (95% confidence interval) of the overall cancer screening among the cancer survivors, compared to others, were 1.16 (0.79–1.72) in male and 1.78 (1.20–2.63) in female participants, after the adjustment for confounding variables. The odds ratios (95% confidence interval) for opportunistic cancer screening and National Cancer Screening Program among cancer survivors were 1.56 (1.07–2.27) and 0.80 (0.53–1.21) in males and 2.05 (1.46–2.88) and 0.66 (0.46–0.95) in females. CONCLUSION: Female cancer survivors showed a higher rate of overall and opportunistic cancer screening than did the male cancer survivors. Further efforts are required to improve cancer screening among male cancer survivors.
Adult ; Confounding Factors (Epidemiology) ; Cross-Sectional Studies ; Diagnosis ; Early Detection of Cancer ; Female ; Humans ; Korea ; Male ; Mass Screening ; Neoplasms, Second Primary ; Nutrition Surveys ; Odds Ratio ; Recurrence ; Survivors ; Weights and Measures

BACKGROUND: Exposure to secondhand smoke (SHS) has been shown to cause health problems. Recent studies demonstrated an association of SHS with depression and poor mental health. The urinary cotinine concentration (Ucot) is an objective indicator of exposure to SHS. In this study, we evaluated the association between depression and Ucot in adult non-smokers adults in Korea. METHODS: We analyzed the data of 3,417 adults, aged ≥19 years, who participated in the seventh Korea National Health and Nutrition Examination Survey (2016). The eligible subjects were non-smokers. Depression was evaluated using the Patient Health Questionnaire-9 (PHQ-9). The subjects were dichotomized into two groups: the high depressive symptom group (PHQ-9 ≥10 [n=185]) and the low depressive symptom group (PHQ-9 <10 [n=3,232]). The demographic, socioeconomic, and clinical characteristics of the subjects were retrieved from the survey data. Ucot was dichotomized into high-Ucot (≥10 ng/mL) and low-Ucot (<10 ng/mL). The Ucot and other characteristics were compared between the two groups. To adjust for confounding variables, we conducted a logistic regression analysis and determined the difference in Ucot between the two groups. RESULTS: After adjusting for confounders, the high depressive symptom group was found to be associated with high-Ucot (odds ratio, 1.824; 95% confidence interval, 1.020–3.262). Sex, education, socioeconomic status, marital status, occupational status, limitation of activity, and the presence of an underlying diseases (diabetes and dyslipidemia) had a significant effect on depression. CONCLUSIONS: This concluded that depression was associated with high urine cotinine level in adult non-smokers.
Adult ; Confounding Factors (Epidemiology) ; Cotinine ; Depression ; Education ; Employment ; Humans ; Korea ; Logistic Models ; Marital Status ; Mental Health ; Nutrition Surveys ; Social Class ; Tobacco ; Tobacco Smoke Pollution

PURPOSE: This study aims to investigate the effects of smoking on the development of placenta-associated syndromes, including preeclampsia, abruptio placentae, and placenta previa, which share the common pathophysiology of vascular compromise of the placenta. METHODS: A total of 966,629 pregnancies identified from the Korean National Insurance Claims Database and the National Health Information Database were analyzed from 2010 to 2014. The adjusted odds ratio and attributable risk of smoking for the development of placenta-associated syndromes, such as preeclampsia, placenta previa, and abruptio placentae, were analyzed. Maternal age, alcohol consumption, exercise habit, and economic status were controlled as confounding variables. A binary logistic regression model was used, and simple and multiple logistic regression analyses were performed. RESULTS: Among 966,629 pregnancies, 11.86% of women were ever smokers. Ever smokers had a higher risk of developing placenta previa (adjusted odds ratio, 1.23; 95% confidence interval [CI], 1.18–1.29; adjusted attributable risk, 18.70%). The adjusted odds ratio of developing placenta-associated syndromes in ever smokers compared to nonsmokers over the age of 35 years with a low economic status was 1.32 (95% CI, 1.18–1.47), with an adjusted attributable risk of 23.95%. CONCLUSION: The risk of developing placenta-associated syndromes, such as preeclampsia, placenta previa, and abruptio placentae, is high in ever smokers. Pregnant ever smokers who are >35 years and belong to the lower one-third of the economic division require special care to prevent the development of placenta-associated syndromes.
Abruptio Placentae ; Alcohol Drinking ; Confounding Factors (Epidemiology) ; Female ; Humans ; Insurance ; Korea ; Logistic Models ; Maternal Age ; Odds Ratio ; Placenta ; Placenta Previa ; Pre-Eclampsia ; Pregnancy ; Smoke ; Smoking

BACKGROUND: Chronic kidney disease (CKD)-mineral and bone disorder (MBD) and fracture risk are both closely related to declining renal function. Controlling hyperphosphatemia with phosphate binders is a basic principle of CKD-MBD treatment. The aim of this study was to identify differences in fracture risk between pre-dialysis CKD patients and end-stage renal disease (ESRD) on dialysis, and to evaluate the effects of phosphate binders on fracture risk in ESRD patients. METHODS: Data from a total of 89,533 CKD patients comprising CKD diagnosis, dialysis, fracture history, and phosphate binder prescription history from 2012 to 2016 were retrieved from the Health Insurance Review and Assessment Service Database. Multivariate Cox regression analyses were performed to identify whether dialysis or phosphate binders were associated with an increased fracture risk. RESULTS: Overall, the rate of fractures in pre-dialysis CKD patients was 74 per 1,000 patient-years, while that in dialysis patients was 84 per 1,000 patient-years. The risk of fracture in ESRD patients was higher than pre-dialysis CKD patients (hazard ratio, 1.16; 95% confidence interval, 1.12–1.21; P < 0.001) after adjusting for confounding variables. In addition, the fracture risk in patients who were not taking phosphate binders was 20.0% higher compared to ESRD patients taking phosphate binders. CONCLUSION: Fractures were more prevalent in ESRD patients on dialysis than pre-dialysis CKD patients. Use of phosphate binders was associated with a lower fracture risk in ESRD patients.
Cohort Studies ; Confounding Factors (Epidemiology) ; Diagnosis ; Dialysis ; Humans ; Hyperphosphatemia ; Insurance, Health ; Kidney Failure, Chronic ; Prescriptions ; Renal Insufficiency, Chronic

OBJECTIVES: Nicotine narrows uterine blood vessels reducing the flow of oxygen and nutrients to the developing fetus. This study examined the effects of fetal exposure to secondhand smoke on neonatal anthropometry. METHODS: This cross sectional study recruited 128 pregnant women in the third trimester of single pregnancies who had no chronic illness, were not active or ex-smokers, and who were willing to participate in the study. Pregnant women who were exposed to secondhand smoke had umbilical cord blood nicotine concentrations of ≥ 1 ng/mL. Neonatal anthropometry was assessed according to the newborn birth weight and length. The independent t-test was used to determine the neonatal difference in mean birth weight and length between the women who were exposed to secondhand smoke, and those who were not exposed. A multiple linear regression analysis was employed to assess the effect of secondhand smoke exposure on birth weight and birth length, controlling for potential confounding variables (weight gain during pregnancy, body mass index, parity, maternal age, and maternal hemoglobin). RESULTS: There were 35 women exposed to secondhand smoke (nicotine ≥ 1 ng/mL). Neonate birth weight and birth length were lower among mothers who were exposed to secondhand smoke. However, only neonate birth weight was significantly reduced by exposure to secondhand smoke (p = 0.005). The mean birth weight of these neonates was 2,916.5 g ± 327.3 g which was 205.6 g less than in unexposed fetuses. CONCLUSION: Exposure of mothers to secondhand smoke during pregnancy reduces fetal development and neonatal weight.
Anthropometry ; Birth Weight ; Blood Vessels ; Body Mass Index ; Chronic Disease ; Confounding Factors (Epidemiology) ; Female ; Fetal Blood ; Fetal Development ; Fetus ; Humans ; Infant, Newborn ; Linear Models ; Maternal Age ; Mothers ; Nicotine ; Oxygen ; Parity ; Parturition ; Pregnancy ; Pregnancy Trimester, Third ; Pregnant Women ; Tobacco Smoke Pollution ; Umbilical Cord

Our study aimed to analyze the clinical characteristics and psychotropic prescription patterns of a history of suicide attempts in South Koreans with bipolar disorder (BD), by using only Korean data from the Research on Asian Psychotropic Prescription Pattern for Bipolar disorder. The patterns of clinical characteristics and psychotropic drug use were compared among 53 patients with a history of suicide attempts and 297 without this history; the potential effects of confounding variables were adjusted with binary logistic analyses for discrete variables and analyses of covariance for continuous variables. After adjusting the effects of age, sex, duration of illness, and enrollment as an outpatient, patients with a history of suicide attempts were characterized by a significantly more prevalent depressive episode, lower prevalent remission state, lower levels of hemoglobin, and more use of antidepressants, anxiolytics, and hypnotics compared to those without lifetime suicide attempt. The inability to plan goal-directed behavior may be an intervening factor in the relationship between suicide attempts and depression in BD. Relatively low hemoglobin levels can be associated with manic episodes in patients with a history of suicide attempts and the use of antidepressants, anxiolytics, or hypnotics can be associated with suicide attempts in BD patients.
Anti-Anxiety Agents ; Antidepressive Agents ; Asian Continental Ancestry Group ; Bipolar Disorder ; Confounding Factors (Epidemiology) ; Depression ; Drug Prescriptions ; Humans ; Hypnotics and Sedatives ; Korea ; Outpatients ; Prescriptions ; Suicide