Depression, one of the most costly and common mental disorders, is reported to be associated with lower quality of life (QoL) in several studies. Improved understanding of the associated factors with QoL is necessary to optimize long-term outcomes and reduce disability in patients with depression. Therefore, the aim of this study was to identify factors that are associated with lower QoL among patients with depression. The study was based on the Korea National Health and Nutrition Examination Survey, a cross-sectional health examination, years 2008 to 2014. The final analyzed sample consisted of a total of 1,502 study subjects who had been diagnosed by clinicians as having depression. A multivariate logistic regression model was performed to exam the association between the clinical characteristics (age, sex, demographic and health-related characteristics) and QoL. Analysis of covariance was also used to analyze EQ-5D according to mental health. Older age, lower level of education, lower income, worse subjective perception of health, unemployment, obesity and mental health struggles were found to be significantly associated with low QoL in depressive individuals after adjustment for multiple covariates. This study has outlined grounding data in identifying patients who are at risk of QoL impairment. Policy makers should direct their interests to these individuals and provide appropriate management.

Background: The association of metabolic syndrome and its components with the risk of thyroid cancer is unclear. Thus, we conducted a large-scale, nationwide, population-based, cohort study to investigate this relationship. Methods: We studied 9,890,917 adults without thyroid cancer from the Korean National Health Insurance health checkup database from January 1 to December 31, 2009. Individuals with at least three of the following five components were diagnosed with metabolic syndrome: abdominal obesity, hypertriglyceridemia, low high-density lipoprotein-cholesterol levels, elevated blood pressure, and hyperglycemia. Multivariate Cox proportional hazards models were used to estimate thyroid cancer risk. Results: During the average 7.2 years of follow-up, 77,133 thyroid cancer cases were newly identified. The thyroid cancer risk was higher in the metabolic syndrome group than in the nonmetabolic syndrome group (hazard ratio [HR] 1.15 [95% confidence interval, CI 1.13–1.17]). The association between metabolic syndrome and thyroid cancer risk was significant in the obese group (HR 1.10 [CI 1.07–1.13]) and not in the nonobese group (HR 1.002 [CI 0.98–1.03]). The effect of metabolic syndrome on the risk of thyroid cancer differs according to obesity ( p for interaction = 0.017). People with all five components of metabolic syndrome had a 39% higher risk than those without any components (HR 1.39 [CI 1.33–1.44]). The higher risk of thyroid cancer in people with all five components was significant in the obese group (HR 1.29 [CI 1.21–1.38]), but not in the nonobese group (HR 1.06 [CI 0.98–1.14]). There was a significant interaction between the number of metabolic syndrome components and obesity ( p for interaction <0.0001). For the combined effect of obesity and metabolic syndrome on the risk of thyroid cancer, obese men with metabolic syndrome had the highest risk of thyroid cancer compared with those without (HR 1.58 [CI 1.52–1.64]), but obese women with metabolic syndrome did not. Conclusions: Metabolic syndrome was associated with an increased risk of thyroid cancer in the Korean general population. Metabolic syndrome had a more significant risk of thyroid cancer in the obese group. Metabolic syndrome and obesity were associated with a higher risk of thyroid cancer in men but not in women.

The objective of this study was to investigate the relationship between body mass index (BMI) and mortality in the elderly. This study was a nation-wide population-based retrospective cohort study of the National Health Insurance System-Senior Database (NHIS-SD). In this study, a total of 75,856 subjects were identified and selected from among 251,593 individuals aged ≥ 65 years who underwent health screening at least once between 2009 and 2012 and who had no history of diabetes, cardiovascular disease, stroke, cancer, or chronic obstructive pulmonary disease (COPD). The subjects of this study were followed-up until 2013 to identify the total mortality and the cause-specific mortality of 6 groups divided according to BMI. The hazard ratio (HR) by reference group (23 ≤ BMI < 25 kg/m²) of each group was calculated. A significant increase in the HR with a decreased BMI was observed in the group with a BMI < 23 kg/m², whereas the HR in the group with a BMI ≥ 25 kg/m² was not significantly different than that of the reference group (23 ≤ BMI < 25 kg/m²). This pattern was also seen in the subgroup analyses in relation to age, smoking history, alcohol use, exercise level, and socioeconomic status. In this study, we found that a low BMI was a risk factor for death in the elderly and that no significant difference in mortality was seen in the elderly with a BMI of 25 or over. In terms of an optimal BMI in the elderly, it is important to maintain an appropriately healthy range of BMI with the aim of preventing weight loss.

PURPOSE: To determine whether the dose-response association between alcohol consumption and the risk of biliary tract cancer (BTC), including cholangiocarcinoma (CCA) and gallbladder cancer (GBC), differs according to glycemic status. PATIENTS AND METHODS: This nationwide cohort study included 9,520,629 individuals age ≥ 20 years without a history of cancer who underwent national health screening under the Korean National Health Insurance Service in 2009. The participants were followed up until December 2018 for BTC development. Cox proportional hazard regression analysis was performed to estimate risk. RESULTS: During the 78.3 million person-years of follow-up, 21,079 patients were newly diagnosed with BTC. In individuals with prediabetes and diabetes, light-to-moderate alcohol consumption increased the risk of CCA (adjusted hazard ratio [aHR], 1.20; 95% CI, 1.13 to 1.28 and aHR, 1.58; 95% CI, 1.47 to 1.69) and GBC (aHR, 1.18; 95% CI, 1.07 to 1.31 and aHR, 1.45; 95% CI, 1.28 to 1.64). In normoglycemic individuals, light-to-moderate alcohol consumption was not associated with CCA or GBC risk. When heavy alcohol consumption was combined with diabetes, CCA and GBC risk increased synergistically (aHR, 2.04; 95% CI, 1.83 to 2.26; and aHR, 1.65; 95% CI, 1.33 to 2.04, respectively; all P < .001). Prediabetes and heavy alcohol consumption had a synergistic interactive effect on CCA and GBC risks (all P < .001). Comparable results were obtained for intrahepatic and extrahepatic CCA analyses. CONCLUSION: Even light-to-moderate alcohol consumption was associated with an increased risk of BTC in individuals with prediabetes and diabetes, but not in normoglycemic individuals. Complete avoidance of alcohol consumption may help reduce the risk of BTC in patients with prediabetes and diabetes, suggesting the need for individualized prevention strategies for BTC.

The aim of this study was to investigate the prescribing cascade phenomenon of dopaminergic drugs such as levodopa in the management of gastroprokinetic drugs induced parkinsonism. Based on the Korea National Health Insurance Service (NHIS)-Senior Cohort Database, we analyzed patients aged ≥65 years, between 2009 and 2013, who obtained new prescriptions for levodopa through the NHIS during this period. Those who were prescribed levodopa from 2002 to 2008 were excluded, only patients who were prescribed metoclopramide and levosulpiride within 90 days of receiving the levodopa prescription were included. Those who did not receive levodopa were used as a control group for 1:3 age and sex matching. We assessed 1824 and 1197 levodopa cases for metoclopramide and levosulpiride use, respectively. The matched controls for each levodopa case were 5472 and 3591, respectively. We used conditional logistic regression to determine the odds ratio (OR) for initiation of levodopa therapy in patients using metoclopramide and levosulpiride, relative to nonusers, after adjusting for age, sex, and exposure to antipsychotic medication. Both metoclopramide (OR = 3.04; 95% confidence interval, CI, 2.46–3.77) and levosulpiride (OR = 3.32; 95% CI, 2.56–4.3) users were three times more likely to begin using medication containing levodopa, compared to nonusers. Metoclopramide and levosulpiride were frequently prescribed within 90 days of receiving a prescription for levodopa. Before prescribing levodopa, it should be considered whether the adverse event is actually a side effect caused by metoclopramide and levosulpiride.