OBJECTIVES: Previous epidemiological studies about oxidative stress and depression are limited by hospital-based case-control design, single-time measurements of oxidative stress biomarkers, and the small number of study participants. Therefore, in this study, we analyzed the association between biomarker of oxidative stress and depressive symptom scores using repeatedly measured panel data from a community-dwelling elderly population. METHODS: From 2008 to 2010, a total of 478 elderly participants residing in Seoul, Korea, were evaluated three times. Participants underwent the Korean version of the Short Form Generic Depression Scale (SGDS-K) test for screening depression, and urinary malondialdehyde (MDA) levels were measured as an oxidative stress biomarker. We used a generalized estimating equation with a compound symmetry covariance structure to estimate the effects of oxidative stress on depressive symptom scores. RESULTS: A two-fold increase in urinary MDA concentration was significantly associated with a 33.88% (95% confidence interval [CI], 21.59% to 47.42%) increase in total SGDS-K scores. In subgroup analyses by gender, a two-fold increase in urinary MDA concentration was significantly associated with increased SGDS-K scores in both men and women (men: 30.88%; 95% CI, 10.24% to 55.37%; women: 34.77%; 95% CI, 20.09% to 51.25%). In bivariate analysis after an SGDS-K score ≥8 was defined as depression, the third and the fourth urinary MDA quartiles showed a significantly increased odds ratio(OR) of depression compared to the lowest urinary MDA quartile (third quartile OR, 6.51; 95% CI, 1.77 to 24.00; fourth quartile OR, 7.11; 95% CI, 1.99 to 25.42). CONCLUSIONS: Our study suggests a significant association between oxidative stress and depressive symptoms in the elderly population.
Aged* ; Biomarkers ; Case-Control Studies ; Depression* ; Depressive Disorder ; Epidemiologic Studies ; Female ; Humans ; Korea ; Male ; Malondialdehyde ; Mass Screening ; Oxidative Stress* ; Seoul

OBJECTIVE: This study aims to reveal the relationship of depression with growth factors such as brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), and insulin-like growth factor-1 (IGF-1) in inpatients diagnosed with alcohol dependence, and to identify candidate growth factors as biological markers to indicate the comorbid of alcohol dependence and depression. METHODS: This study examined demographic factors in 45 alcohol-dependent patients. The ADS (Korean version of the Alcohol Dependence Scale) and BDI (Korean version of Beck's Depression Inventory) were used. BDNF, NGF, and IGF-1 were measured through ELISA. RESULTS: The average drinking quantity and the ADS score were significantly more severe in alcohol-dependent patients with depression than in those without depression. Linearly comparing BDNF, NGF, and IGF-1 with BDI values, IGF-1 was the growth factor significantly correlated with BDI scores. BDI scores were significantly correlated with ADS scores. IGF-1 was significantly higher in alcohol-dependent patients with depression. Alcohol-dependent patients with depression had greater alcohol use and more severe ADS scores. BDNF and NGF showed no significant difference between alcohol-dependent patients with and without depression, but IGF-1 was significantly higher in those with than in those without depression. CONCLUSION: IGF-1 was found to be associated with depression in alcohol-dependent patients, suggesting that IGF-1 in alcohol-dependent patients could be an important biomarker to indicate whether alcohol-dependence is accompanied by depression.
Alcoholism ; Biomarkers ; Brain-Derived Neurotrophic Factor ; Demography ; Depression* ; Drinking ; Enzyme-Linked Immunosorbent Assay ; Humans ; Inpatients ; Insulin-Like Growth Factor I ; Intercellular Signaling Peptides and Proteins* ; Nerve Growth Factor

BACKGROUND: We aimed to evaluate the spatial and temporal trends of the health burden attributable to particulate matter less than 2.5 µm in diameter (PM2.5) in the metropolitan cities and provinces of the Korea. METHODS: We used modeled PM2.5 concentration data for the basic administrative levels, comprising the cities and the provinces of Korea, the corresponding annual population census data for each level, and the age and cause specific mortality data. We applied cause-specific integrated exposure-response functions to calculate the premature mortality attributable to ambient PM2.5 for four disease end points (ischemic heart disease [IHD], chronic obstructive pulmonary disease [COPD], lung cancer [LC], and cerebrovascular disease [stroke]) for the year 2015. Moreover, the temporal trends of the health burden from 2006 to 2015 were assessed. RESULTS: The annual average PM2.5 concentration for Korea was 24.4 μg/m3, and 11,924 premature deaths were attributable to PM2.5 exposure in 2015. By simulating the reduction in the annual mean values of PM2.5 to 10 µg/m3, about 8,539 premature deaths were preventable. There was spatial variation in mortality burden attributable to PM2.5 across the sub-national regions of Korea. In particular, the high burden was concentrated at Seoul and Gyeonggi province due to the high population density. However, decreasing trends were noted for most of the metropolitan cities and provinces of Korea since 2006. CONCLUSION: Our findings show that further actions to improve air quality in Korea would substantially improve the health burden due to particulate matter.
Censuses ; Cerebrovascular Disorders ; Gyeonggi-do ; Heart Diseases ; Korea* ; Lung Neoplasms ; Mortality ; Mortality, Premature ; Particulate Matter ; Population Density ; Pulmonary Disease, Chronic Obstructive ; Seoul

PURPOSE: Intravenous lipid emulsion (ILE) has been shown to have significant therapeutic effects on calcium channel blocker overdose in animal studies and clinical cases. In this preliminary experiment, we investigated the hemodynamic changes and survival in a rat model of verapamil intoxication. METHODS: Fourteen male Sprague-Dawley rats were sedated and treated with ILE or normal saline (control), followed by continuous intravenous infusion of verapamil (20 mg/kg/h). Mean arterial pressure and heart rate of rats were monitored during the infusion. In addition, the total dose of infused verapamil and the duration of survival were measured. RESULTS: Survival was prolonged in the ILE group (32.43±5.8 min) relative to the control group (24.14±4.3 min) (p=0.01). The cumulative mean lethal dose of verapamil was higher in the ILE group (4.3±0.7 mg/kg) than in the control group (3.2±0.5 mg/kg; p=0.017). CONCLUSION: ILE pretreatment prolonged survival and increased the lethal dose in a rat model of verapamil poisoning.
Animals ; Arterial Pressure ; Calcium Channels ; Heart Rate ; Hemodynamics ; Humans ; Infusions, Intravenous ; Male ; Models, Animal* ; Poisoning ; Rats* ; Rats, Sprague-Dawley ; Therapeutic Uses ; Verapamil*

BACKGROUND: Sedation by dexmedetomidine, like natural sleep, often causes bradycardia. We explored the nature of heart rate (HR) changes as they occur during natural sleep versus those occurring during dexmedetomidine sedation. METHODS: The present study included 30 patients who were scheduled to undergo elective surgery with spinal anesthesia. To assess HR and sedation, a pulse oximeter and bispectral index (BIS) monitor were attached to the patient in the ward and the operating room. After measuring HR and BIS at baseline, as the patients slept and once their BIS was below 70, HR and BIS were measured at 5-minute intervals during sleep. Baseline HR and BIS were also recorded before spinal anesthesia measured at 5-minute intervals after dexmedetomidine injection. RESULTS: During natural sleep, HR changes ranged from 2 to 19 beats/min (13.4 ± 4.4 beats/min), while in dexmedetomidine sedation, HR ranged from 9 to 40 beats/min (25.4 ± 8.5 beats/min). Decrease in HR was significantly correlated between natural sleep and dexmedetomidine sedation (R2 = 0.41, P < 0.001). The lowest HR was reached in 66 min during natural sleep (59 beats/min) and in 13 min with dexmedetomidine sedation (55 beats/min). The time to reach minimum HR was significantly different (P < 0.001), but there was no difference in the lowest HR obtained (P = 0.09). CONCLUSIONS: There was a correlation between the change in HR during natural sleep and dexmedetomidine sedation. The bradycardia that occurs when using dexmedetomidine may be a normal physiologic change, that can be monitored rather than corrected.
Anesthesia, Spinal ; Bradycardia ; Dexmedetomidine ; Heart Rate ; Heart ; Humans ; Hypnotics and Sedatives ; Operating Rooms

BACKGROUND: Sedation by dexmedetomidine, like natural sleep, often causes bradycardia. We explored the nature of heart rate (HR) changes as they occur during natural sleep versus those occurring during dexmedetomidine sedation. METHODS: The present study included 30 patients who were scheduled to undergo elective surgery with spinal anesthesia. To assess HR and sedation, a pulse oximeter and bispectral index (BIS) monitor were attached to the patient in the ward and the operating room. After measuring HR and BIS at baseline, as the patients slept and once their BIS was below 70, HR and BIS were measured at 5-minute intervals during sleep. Baseline HR and BIS were also recorded before spinal anesthesia measured at 5-minute intervals after dexmedetomidine injection. RESULTS: During natural sleep, HR changes ranged from 2 to 19 beats/min (13.4 ± 4.4 beats/min), while in dexmedetomidine sedation, HR ranged from 9 to 40 beats/min (25.4 ± 8.5 beats/min). Decrease in HR was significantly correlated between natural sleep and dexmedetomidine sedation (R2 = 0.41, P < 0.001). The lowest HR was reached in 66 min during natural sleep (59 beats/min) and in 13 min with dexmedetomidine sedation (55 beats/min). The time to reach minimum HR was significantly different (P < 0.001), but there was no difference in the lowest HR obtained (P = 0.09). CONCLUSIONS There was a correlation between the change in HR during natural sleep and dexmedetomidine sedation. The bradycardia that occurs when using dexmedetomidine may be a normal physiologic change, that can be monitored rather than corrected.

Objectives: Excess mortality associated with long-term exposure to fine particulate matter (PM2.5) has been documented. However, research on the disease burden following short-term exposure is scarce. We investigated the cause-specific mortality burden of short-term exposure to PM2.5 by considering the potential non-linear concentration–response relationship in Korea. Methods: Daily cause-specific mortality rates and PM2.5 exposure levels from 2010 to 2019 were collected for 8 Korean cities and 9 provinces. A generalized additive mixed model was employed to estimate the non-linear relationship between PM2.5 exposure and cause-specific mortality levels. We assumed no detrimental health effects of PM2.5 concentrations below 15 μg/m3. Overall deaths attributable to short-term PM2.5 exposure were estimated by summing the daily numbers of excess deaths associated with ambient PM2.5 exposure. Results: Of the 2 749 704 recorded deaths, 2 453 686 (89.2%) were non-accidental, 591 267 (21.5%) were cardiovascular, and 141 066 (5.1%) were respiratory in nature. A non-linear relationship was observed between all-cause mortality and exposure to PM2.5 at lag0, whereas linear associations were evident for cause-specific mortalities. Overall, 10 814 all-cause, 7855 non-accidental, 1642 cardiovascular, and 708 respiratory deaths were attributed to short-term exposure to PM2.5. The estimated number of all-cause excess deaths due to short-term PM2.5 exposure in 2019 was 1039 (95% confidence interval, 604 to 1472). Conclusions Our findings indicate an association between short-term PM2.5 exposure and various mortality rates (all-cause, non-accidental, cardiovascular, and respiratory) in Korea over the period from 2010 to 2019. Consequently, action plans should be developed to reduce deaths attributable to short-term exposure to PM2.5.

The poisoning information database (PIDB) provides clinical toxicological information on commonly encountered toxic substances in Korea. The aim of this study was to estimate the coverage rate of the PIDB by comparing the database with the distribution of toxic substances that real poisoning patients presented to 20 emergency departments. Development of the PIDB started in 2007, and the number of toxic substances increased annually from 50 to 470 substances in 2014. We retrospectively reviewed the medical records of patients with toxic exposure who visited 20 emergency departments in Korea from January to December 2013. Identified toxic substances were classified as prescription drug, agricultural chemical, household product, animal or plant, herbal drug, or other. We calculated the coverage rate of the PIDB for both the number of poisoning cases and the kinds of toxic substances. A total of 10,887 cases of intoxication among 8,145 patients was collected. The 470 substances registered in the PIDB covered 89.3% of 8,891 identified cases related to poisoning, while the same substances only covered 45.3% of the 671 kinds of identified toxic substances. According to category, 211 prescription drugs, 58 agricultural chemicals, 28 household products, and 32 animals or plants were not covered by the PIDB. This study suggested that the PIDB covered a large proportion of real poisoning cases in Korea. However, the database should be continuously extended to provide information for even rare toxic substances.
Adolescent ; Adult ; Aged ; Animals ; Animals, Poisonous ; Child ; Child, Preschool ; Databases, Factual ; Drugs, Chinese Herbal/poisoning ; Emergency Service, Hospital ; Female ; Humans ; Infant ; Male ; Middle Aged ; Pesticides/poisoning ; Plants, Medicinal/poisoning ; Poisoning/*epidemiology ; Prescription Drugs/poisoning ; Republic of Korea ; Retrospective Studies ; Young Adult

OBJECTIVE: Radiation is used extensively in emergency centers. Computed tomography and X-ray imaging are used frequently. Portable X-rays, in particular, cause a significant amount of indirect radiation exposure to medical personnel. The authors' emergency center was remodeled, and a comparative study of radiation exposure was carried out in certain places that had experienced radiation for a long time. METHODS: The cumulative radiation dose was measured 20 times in the 24 hours prior to remodeling, and the cumulative radiation dose was measured again 20 times across the 24-hour period. The measurement points were fixed at the emergency doctor's seat (Zone A), charge nurse's seat (Zone B), and section nurse's seat (Zone C). During the 24-hour cumulative radiation measurement period, the number of portable X-ray shots was recorded in the emergency center. RESULTS: The mean of the 24-hour cumulative radiation measurements in zone A was 3.36±0.07 µSV and 4.54±0.07 µSV before and after remodeling, respectively (P<0.001). Regarding the number of portable X-rays performed during the measurement, a higher number of trials in the Pearson correction correlated with a higher radiation measurement. CONCLUSION: In an emergency medical center, there is a higher level of low-dose radiation exposure compared to that experienced from natural radioactivity. Regarding the number of portable X-rays, the cumulative radiation dose measured 24 hours after remodeling increased and can be assumed to be related to the environment.
Emergencies ; Radiation Exposure ; Radioactivity