Association between Near Work Time and Depression among Workers in South Korea.

BACKGROUND: The aim of this study was to evaluate the association between near work time and depression. METHODS: Data of 1,551 workers aged 19-49 years from the sixth Korea National Health and Nutrition Examination Survey were examined. The Patient Health Questionaire-9 scores were used to screen for depression. Participants who scored a total of 10 or above, which is suggestive of the presence of depression, were classified as the depression group; the rest were classified as normal. The correlation between daily near work time and depression was analyzed using multivariate logistic analysis after adjusting for other sociodemographic and health behavior-related variables. RESULTS: Multivariate logistic analysis found that workers with 3 or more hours of near work were more likely to report depression compared to the reference group who had 2 or fewer hours per day of near work (adjusted odds ratio, 2.471; 95% confidence interval, 1.062-5.747). CONCLUSION: Longer near work time was associated with depression among South Korea's workers. Therefore, it is necessary to reduce near work time to prevent depression.

The Risk of Osteoporosis and Osteoporotic Fracture Following the Use of Irritable Bowel Syndrome Medical Treatment: An Analysis Using the OMOP CDM Database.

Patients with irritable bowel syndrome (IBS) are at increased risk of osteoporosis and osteoporotic fracture. This study investigated whether IBS medication attenuated the rate of osteoporosis and osteoporotic fracture risk. We conducted a retrospective large-scale multicenter study across eight hospital databases encoded in the Observational Medical Outcomes Partnership (OMOP) Common Data Model (CDM). The primary outcome was the incidence of osteoporosis, whereas secondary outcomes were osteoporotic fractures. After 1:4 matching, 24,723 IBS patients, 78,318 non-IBS patients, 427,640 non-IBS patients with IBS medication, and 827,954 non-IBS patients without IBS medication were selected. The risk of osteoporosis was significantly increased in the IBS group compared to the non-IBS group (hazard ratio (HR) 1.33; confidence interval (CI) 1.17~1.51). Even in patients who were not diagnosed with IBS, the risk of osteoporosis was significantly increased in those with IBS medication compared to those without (HR 1.77, CI 1.62~1.93). The risk of osteoporotic fracture was significantly increased in the IBS medication group (HR 1.69, CI 1.55~1.84). Patients exposed to IBS treatment even without IBS diagnosis were at increased risk of osteoporosis and osteoporotic fracture. Early diagnosis and treatment of osteoporosis should be considered in patients who have received medication for IBS symptoms.

Genetic changes in plaque-purified varicella vaccine strain Suduvax during in vitro propagation in cell culture.

Infection by varicella-zoster virus (VZV) can be prevented by using live attenuated vaccines. VZV vaccine strains are known to evolve rapidly in vivo, however, their genetic and biological effects are not known. In this study, the plaque-purified vaccine strain Suduvax (PPS) was used to understand the genetic changes that occur during the process of propagation in in vitro cell culture. Full genome sequences of three different passages (p4, p30, and p60) of PPS were determined and compared for genetic changes. Mutations were found at 59 positions. The number of genetically polymorphic sites (GPS) and the average of minor allele frequency (MAF) at GPSs were not significantly altered after passaging in cell culture up to p60. The number of variant nucleotide positions (VNPs), wherein GPS was found in at least one passage of PPS, was 149. Overall, MAF changed by less than 5% at 52 VNPs, increased by more than 5% at 42 VNPs, and decreased by more than 5% at 55 VNPs in p60, compared with that seen in p4. More complicated patterns of changes in MAF were observed when genetic polymorphism at 149 VNPs was analyzed among the three passages. However, MAF decreased and mixed genotypes became unequivocally fixed to vaccine type in 23 vaccine-specific positions in higher passages of PPS. Plaque-purified Suduvax appeared to adapt to better replication during in vitro cell culture. Further studies with other vaccine strains and in vivo studies will help to understand the evolution of the VZV vaccine.

Effect of antimicrobial photodynamic therapy with Chlorella and Curcuma extract on Streptococcus mutans biofilms.

BACKGROUND: Antimicrobial photodynamic therapy (aPDT) using natural photosensitive agents is an effective method for preventing oral diseases of bacterial origin. The purpose of this study was to evaluate the antimicrobial effect of aPDT, using powdered extracts of Chlorella and Curcuma, on the biofilms of Streptococcus mutans (S. mutans), a bacterium that is known to cause dental caries. METHODS: Commercially available powdered Chlorella and Curcuma extracts were used as photosensitizers. S. mutans, cultured for 2 days, was inoculated (0.1 ml; 1 × 109 CFU/ml) on the surface of a hydroxyapatite (HA) disc and incubated for 24 h to allow the formation of a biofilm. The HA disc with the S. mutans biofilm was immersed in either Curcuma extract (0.5 mg/ml), Chlorella extract, distilled water (negative control), or Listerine (positive control) for 1 min and then irradiated with an LED (Qraycam; wavelength, 405 nm; energy, 59 mW) for 5 min. RESULTS: The application of aPDT with Curcuma or Chlorella extract to S. mutans 24-hour biofilms significantly decreased the number of viable cells and the live/dead cell ratio when compared with those in the negative control (distilled water; p < 0.05). CONCLUSIONS: aPDT using 405 nm light and Chlorella or Curcuma as a photosensitizer has significant antimicrobial effects against S. mutans biofilms. Thus, employing aPDT with natural plant extracts as photosensitizers could be an effective strategy for preventing dental caries but needs to be evaluated in properly controlled clinical trials..

Association between Irritable Bowel Syndrome and Risk of Osteoporosis in Korean Premenopausal Women.

OBJECTIVE: The objective of this study is to evaluate irritable bowel syndrome (IBS) as a risk factor for osteoporosis and osteoporotic fracture in Korean women after controlling for basic confounding factors and considering detailed demographic and clinical information. SUBJECTS AND METHODS: We performed a nationwide population-based retrospective cohort analysis and matched every IBS case with a non-IBS case at a 1:4 frequency ratio based on age. The population consisted of female patients with data in the Health Insurance Review and Assessment (HIRA) database from 2002 to 2010. To determine the risk of osteoporosis and osteoporotic fracture in IBS and non-IBS patients, hazard ratios (HRs) with 95% confidence intervals (CI) were estimated using Cox proportional hazards regression models, adjusting for confounding variables, such as the area of residence, health insurance type, and economic status. RESULTS: We identified 1,017,468 patients in the HIRA database with data from 2002 to 2010 who could potentially be included in the cohort. Among these, we identified 1,545 (11.4%) women (age >19 years) with newly diagnosed IBS (IBS group). Additionally, 6,180 patients without IBS and age-matched to the IBS group were selected. Cox modeling revealed that the crude HRs for osteoporosis and osteoporotic fractures in patients with IBS were 1.476 (95% CI, 1.241-1.754) and 1.427 (95% CI, 1.086-1.876), respectively. CONCLUSION: Our data showed an increased incidence of osteoporosis and osteoporotic fractures in women with IBS compared with age-matched controls.

The Relationship of Sitting Time and Physical Activity on the Quality of Life in Elderly People.

Few studies have shown the combined impact of sitting time and physical activity on quality of life in older people. This cross-sectional study, using data from the 2016-2018 Korean National Health and Nutrition Examination Survey, examines the association between sitting time and physical activity and health-related quality of life (HRQoL) in Korean adults aged ≥ 65 years. HRQoL was assessed using the EuroQol-5 Dimension (EQ-5D, three-level version). We divided subjects into groups based on sitting time and physical activity and analyzed the combined association of sitting time and physical activity with HRQoL. The association between longer sitting time (≥8 h) and HRQoL was analyzed using multiple logistic regression. In total, 4276 participants were included. Prolonged sitting time was associated with all of the EQ-5D dimensions: mobility (odds ratio [OR]: 1.43, 95% confidence interval [CI]: 1.22-1.68), self-care (OR: 1.65 [95% CI 1.25-2.17]), usual activities (OR: 2.07 [95% CI 1.69-2.52]), pain/discomfort (OR: 1.57 [95% CI 1.34-1.84]), and anxiety/depression (OR: 1.49 [95% CI 1.17-1.91]). The prolonged sitting time/inactive group had higher ORs for all the EQ-5D dimensions than the low sitting time/active group. Prolonged sitting time was associated with low HRQoL in elderly Korean adults; physical activity could weaken the negative influence of prolonged sitting time on HRQoL.

Association between Time to First Cigarette and Health-Related Quality of Life of Middle-Aged Male Current Smokers: A Nationwide Representative Study in Korea.

BACKGROUND: Although many studies have demonstrated that the first cigarette in the morning increases the prevalence of smoking-related morbidity, limited studies have examined the impact of time to first cigarette (TTFC) on the health-related quality of life (HRQoL). Thus, we assessed this relationship using nationally-representative data from the Korea National Health and Nutrition Examination Survey VII-1 (2016). METHODS: We conducted a cross-sectional study using data from 577 current male smokers aged 30-59 years, after excluding those with a certain disease. Participants were divided into four categories according to TTFC (≤5 min, 6-30 min, 31-60 min, >60 min). HRQoL was measured using self-reported EuroQol-5 (EQ-5D). The relationship between TTFC and EQ-5D index was analyzed using a multivariate-adjusted generalized linear model to assess how HRQoL varies according to TTFC. After adjusting for confounders, a multivariate-adjusted logistic regression analysis was performed to identify which of the five dimensions of the EQ-5D affected the HRQoL according to TTFC. RESULTS: The generalized linear analysis indicated that as TTFC decreased (6-30 min, 31-60 min vs. >60 min), the EQ-5D index score decreased significantly (P=0.037). Shorter TTFC (≤5 min vs. >60 min) was associated with higher pain/discomfort (odds ratio [OR], 3.82; 95% confidence interval [CI], 1.39-10.48) and anxiety/depression (OR, 7.58; 95% CI, 1.75-32.88). CONCLUSION: Higher nicotine dependence was associated with impaired HRQoL. These results may be used to improve smoking cessation treatment outcomes.

Effects of Sleep Patterns on the Subjective Health Status in Older Men from the 7th Korea National Health and Nutrition Examination Survey, 2016.

BACKGROUND: Sleeping is a major component of health. The prevalence of sleep disorders is expected to be high in older adults, and sleep habits generally differ on weekdays and weekends. This study aimed to clarify the associations between sleep habits and the subjective health status of older adults. METHODS: This study analyzed data of 1,678 older adults (695 men and 883 women) aged 65 years or older who had participated in the 2016 Korea National Health and Nutrition Examination Survey (KNHANES VII-1) conducted by the Korea Centers for Disease Control and Prevention. The participants' subjective health perceptions were analyzed according to their sleep habits. RESULTS: Weekday and weekend sleep durations were related to subjective health in older men (p<0.05) but not in women. The subjective health perception was significantly better for a 9-hour sleep duration than for a 7-hour sleep duration in older men. Sleeping and waking times on weekdays and weekends were not related to the subjective health of either men or women. CONCLUSION: Weekday and weekend sleep durations were related to subjective health perception in older men.

Association of Work Patterns and Periodontitis Prevalence in Korean Adults Aged 50 Years or Older: A Nationwide Representative Study.

This study analyzed the relationship between the work pattern and the prevalence of periodontitis. We analyzed the data of 3320 adults (1779 men, 1543 women) aged 51-80 years from the Korean National Health and Nutrition Examination Survey (2013-2015). The work pattern was divided into two groups (regular and irregular). The periodontal status was assessed using the community periodontal index. We observed a statistically significant difference in the association between work patterns and prevalence of periodontitis in Korean women aged over 50 years. For female workers with irregular work patterns, the prevalence of periodontitis was lower than that in workers with regular work patterns by 10.3% (40.3% vs. 30.0%, p = 0.011). The annual health examination rate was significantly higher in the irregular group than in the regular group (for men 77.9% vs. 73.5%; p < 0.001, for women 76.4% vs. 75.9%; p < 0.001). In female workers with irregular work patterns, the annual dental examination rate was significantly higher than that in workers with a regular work pattern by 7.7% (34.3% vs. 26.6%, p = 0.043). In conclusion we found a statistically significant difference between the work patterns and prevalence of periodontitis in Korean women aged over 50 years.

Association Between Weekend Catch-Up Sleep and Metabolic Syndrome with Sleep Restriction in Korean Adults: A Cross-Sectional Study Using KNHANES.

BACKGROUND: Many researchers have identified that adequate sleep duration is linked to the quality of life and metabolic diseases. Nowadays, it is hard to take enough sleep, so weekend catch-up sleep (CUS) may be an alternative option in modern society. To our knowledge, no previous studies reported the association between weekend CUS and metabolic syndrome, especially in the Korean population. OBJECTIVE: We investigated the association between weekend CUS and the prevalence of metabolic syndrome in Korean adults (≥20 years old) with less than 6 hours of average weekday sleep. PATIENTS AND METHODS: A total of 1,453 individuals were selected from the Korean National Health and Nutrition Examination Survey. Weekend CUS was divided into four categories: ≤0 hour, 0-1 hour, 1-2 hours, and ≥2 hours. Odds ratios (ORs) with 95% confidence intervals (CIs) were derived by univariate and multivariate logistic regression analyses. RESULTS: Participants with weekend CUS ≥1 hour had decreased risk of metabolic syndrome in univariate analysis (CUS 1-2 hours: OR: 0.413, 95% CI: 0.301-0.568; CUS ≥2 hours: OR: 0.382, 95% CI 0.296-0.493). Weekend CUS 1-2 hours reduced the risk of metabolic syndrome in multivariate logistic regression analysis (OR: 0.552, 95% CI: 0.369-0.823). Based on the age group analysis, weekend CUS ≥1 hour reduced the metabolic syndrome among those aged 20-39 and 40-65 (20-39: CUS 1-2 hours OR: 0.248, 95% CI: 0.078-0.783, CUS ≥2 hours OR: 0.374, 95% CI: 0.141-0.991; 40-65: CUS 1-2 hours OR: 0.507, 95% CI 0.309-0.832 CUS ≥2 hours OR: 0.638, 95% CI: 0.415-0.981). CONCLUSION: Weekend CUS was associated with a low risk of metabolic syndrome among Korean adults with sleep restriction.