Objectives: The aim of this study was to describe the characteristics of hand-to-environmental contact (HEC) and to identify the factors influencing HEC behavior in Korean adults’ indoor daily life. Methods: Thirty participants were enrolled from January 14 to February 12, 2018 after providing informed consent for being videotaped. Data were collected by recording their indoor daily lives for 2 hours, resulting in 4,732 HEC cases. To ensure the accuracy and reliability of the HEC readings, 3 training sessions were conducted for the videotape readers. Rereading and verifying randomly selected data ensured the validity of intra- and inter-reader readings. Results: The most frequent contact items were phones, papers, computer accessories, and furniture surfaces. The contact density (frequency-duration/min) was highest for category II (items occasionally shared by others, 56.8), followed in descending order by category I (items for individual use, 35.9), and category III (public use items, 3.4). Significant differences in contact density were found according to participants’ demographic characteristics. Conclusion As mobile phones were the most frequent contact item, regular and strict mobile phone cleansing or disinfection strategies are needed, in addition to preventative measures taken for category II and III items. Avoiding sharing personal items with others, refraining from unnecessary HEC, and maintaining strict hand hygiene are recommended.

OBJECTIVES: Hand-to-face contact (HFC) is the major route for the self-inoculation of pathogens. This study aimed to describe the characteristics of HFC behaviors among Korean adults during indoor activities. METHODS: Thirty participants were enrolled in the study, and 2 hours of videotaped data were collected from each participant. Contact data were recorded by examining the frequency and duration of HFC on the videos. Three training sessions were conducted for 2 readers to ensure the accuracy and reliability of videotape reading. Re-reading and verification of selected video data were performed to confirm intrapersonal and interpersonal validity. Contact exposure (CE) was determined by multiplying the contact frequency (CF) by the contact duration (CD) to quantify the intensity of contact during the observation time (2 hours). RESULTS: A total of 3,007 HFCs (1,305 mucous membrane contacts and 1,702 non-mucous membrane contacts) were observed for 60 person-hours. The median CF (person/2 hr) of the mucous membranes (eye; 4.0, nose; 15.5, mouth; 16.5) was 39.5/person and the median total CD was 177.0 sec/person. The median CE (frequency-duration/sec/person) was 5,795.0 (mouth: 1,356.0, nose: 600.0, eye: 57.5). CONCLUSIONS This study showed that the mouth and nose were the most frequent exposure sites for HFC. Avoiding habitual HFC, awareness of self-inoculation by HFC, and vigorous hand hygiene should be strengthened to prevent the spread of infections.

Objectives: The aim of this study was to describe the characteristics of hand-to-environmental contact (HEC) and to identify the factors influencing HEC behavior in Korean adults’ indoor daily life. Methods: Thirty participants were enrolled from January 14 to February 12, 2018 after providing informed consent for being videotaped. Data were collected by recording their indoor daily lives for 2 hours, resulting in 4,732 HEC cases. To ensure the accuracy and reliability of the HEC readings, 3 training sessions were conducted for the videotape readers. Rereading and verifying randomly selected data ensured the validity of intra- and inter-reader readings. Results: The most frequent contact items were phones, papers, computer accessories, and furniture surfaces. The contact density (frequency-duration/min) was highest for category II (items occasionally shared by others, 56.8), followed in descending order by category I (items for individual use, 35.9), and category III (public use items, 3.4). Significant differences in contact density were found according to participants’ demographic characteristics. Conclusion As mobile phones were the most frequent contact item, regular and strict mobile phone cleansing or disinfection strategies are needed, in addition to preventative measures taken for category II and III items. Avoiding sharing personal items with others, refraining from unnecessary HEC, and maintaining strict hand hygiene are recommended.

OBJECTIVES: Hand-to-face contact (HFC) is the major route for the self-inoculation of pathogens. This study aimed to describe the characteristics of HFC behaviors among Korean adults during indoor activities. METHODS: Thirty participants were enrolled in the study, and 2 hours of videotaped data were collected from each participant. Contact data were recorded by examining the frequency and duration of HFC on the videos. Three training sessions were conducted for 2 readers to ensure the accuracy and reliability of videotape reading. Re-reading and verification of selected video data were performed to confirm intrapersonal and interpersonal validity. Contact exposure (CE) was determined by multiplying the contact frequency (CF) by the contact duration (CD) to quantify the intensity of contact during the observation time (2 hours). RESULTS: A total of 3,007 HFCs (1,305 mucous membrane contacts and 1,702 non-mucous membrane contacts) were observed for 60 person-hours. The median CF (person/2 hr) of the mucous membranes (eye; 4.0, nose; 15.5, mouth; 16.5) was 39.5/person and the median total CD was 177.0 sec/person. The median CE (frequency-duration/sec/person) was 5,795.0 (mouth: 1,356.0, nose: 600.0, eye: 57.5). CONCLUSIONS This study showed that the mouth and nose were the most frequent exposure sites for HFC. Avoiding habitual HFC, awareness of self-inoculation by HFC, and vigorous hand hygiene should be strengthened to prevent the spread of infections.

Background: With the increasing frequency of body contouring surgery following weight loss, plastic surgeons have paid considerable attention to subcutaneous fat. However, few studies have investigated superficial and deep fat changes after bariatric surgery, and such studies have been limited to macroscopic assessments. The purpose of this study was to evaluate changes in superficial and deep fat in bariatric surgery patients using computed tomography (CT) to obtain quantitative measurements. Methods: This study included 11 patients (five males, six females; average age, 27 years) who underwent bariatric surgery at Dongsan Medical Center from October 2013 to October 2016. We excluded patients with a body mass index (BMI) <30 kg/m2 and those without both preoperative and postoperative CT images. We analyzed changes in subcutaneous fat area on CT images, with a mean follow-up of 5.5 months. We also performed a subgroup analysis using a BMI cutoff of 40 kg/m2. Results: Patients undergoing bariatric surgery showed significant reductions in weight, total fat, and the area of superficial and deep fat (P=0.002). In patients with a BMI less than 40 kg/m2, the reduction rate of superficial subcutaneous adipose tissue (sSAT) tended to be higher than that of deep subcutaneous adipose tissue (dSAT). Conversely, in patients with a BMI over 40 kg/m2, the reduction rate of dSAT was higher than that of sSAT. Conclusions We observed a difference in the reduction rate of sSAT and dSAT during weight loss after bariatric surgery, although it was not statistically significant. The reduction rates differed according to BMI.

Objectives: This study aimed to develop a valid social contact survey instrument and to verify its feasibility for use among Korean adults. Methods: The Delphi technique was used to develop an instrument to assess social contacts, which was then applied in a cross-sectional pilot study. A panel of 15 medical professionals reviewed the feasibility and validity of each item. The minimum content validity ratio was 0.49. Thirty participants used the developed measure to record contacts during a 24-hour period. Results: After a systematic review, the survey instrument (parts I and II) was developed. Part I assessed social contact patterns over a 24-hour period, and part II assessed perceptions of contacts in daily life and preventive behaviors (hand hygiene and coughing etiquette). High validity and feasibility were found. In the pilot study, the 30 participants had a combined total of 198 contacts (mean, 6.6 daily contacts per person). The participants’ age (p=0.012), occupation (p<0.001), household size (p<0.001), education (p<0.001), personal income (p=0.003), and household income (p<0.001) were significantly associated with the number of contacts. Contacts at home, of long duration, and of daily frequency were relatively likely to be physical. Assortative mixing was observed between individuals in their 20s and 50s. Contact type differed by location, duration, and frequency (p<0.001). Conclusions The developed social contact survey instrument demonstrated high validity and feasibility, suggesting that it is viable for implementation.

OBJECTIVES: Previous research has predominantly focused on total bilirubin levels without clearly distinguishing between direct and indirect bilirubin. In this study, the differences between these forms were examined, and their potential causal relationships with ischemic stroke were investigated. METHODS: Two-sample multivariable Mendelian randomization (MVMR) analysis was employed, extracting summary data on bilirubin from the Korean Cancer Prevention Study-II (n=159,844) and the Korean Genome and Epidemiology Study (n=72,299). Data on ischemic stroke were obtained from BioBank Japan (n=201,800). Colocalization analysis was performed, focusing on the UGT1A1, SLCO1B1, and SLCO1B3 genes, which are the primary loci associated with serum bilirubin levels. RESULTS: Crude 2-sample Mendelian randomization analysis revealed a significant negative association between total bilirubin levels and ischemic stroke. However, in MVMR analyses, only indirect bilirubin demonstrated a significant negative association with ischemic stroke (odds ratio, 0.76; 95% confidence interval, 0.59 to 0.98). Colocalization analysis did not identify a shared causal variant between the 3 genetic loci related to indirect bilirubin and the risk of ischemic stroke. CONCLUSIONS Our study establishes a causal association between higher genetically determined levels of serum indirect bilirubin and reduced risk of ischemic stroke in an Asian population. Future research should include more in-depth analysis of shared genetic variants between indirect bilirubin and ischemic stroke.

OBJECTIVES: Previous research has predominantly focused on total bilirubin levels without clearly distinguishing between direct and indirect bilirubin. In this study, the differences between these forms were examined, and their potential causal relationships with ischemic stroke were investigated. METHODS: Two-sample multivariable Mendelian randomization (MVMR) analysis was employed, extracting summary data on bilirubin from the Korean Cancer Prevention Study-II (n=159,844) and the Korean Genome and Epidemiology Study (n=72,299). Data on ischemic stroke were obtained from BioBank Japan (n=201,800). Colocalization analysis was performed, focusing on the UGT1A1, SLCO1B1, and SLCO1B3 genes, which are the primary loci associated with serum bilirubin levels. RESULTS: Crude 2-sample Mendelian randomization analysis revealed a significant negative association between total bilirubin levels and ischemic stroke. However, in MVMR analyses, only indirect bilirubin demonstrated a significant negative association with ischemic stroke (odds ratio, 0.76; 95% confidence interval, 0.59 to 0.98). Colocalization analysis did not identify a shared causal variant between the 3 genetic loci related to indirect bilirubin and the risk of ischemic stroke. CONCLUSIONS Our study establishes a causal association between higher genetically determined levels of serum indirect bilirubin and reduced risk of ischemic stroke in an Asian population. Future research should include more in-depth analysis of shared genetic variants between indirect bilirubin and ischemic stroke.

OBJECTIVES: Previous research has predominantly focused on total bilirubin levels without clearly distinguishing between direct and indirect bilirubin. In this study, the differences between these forms were examined, and their potential causal relationships with ischemic stroke were investigated. METHODS: Two-sample multivariable Mendelian randomization (MVMR) analysis was employed, extracting summary data on bilirubin from the Korean Cancer Prevention Study-II (n=159,844) and the Korean Genome and Epidemiology Study (n=72,299). Data on ischemic stroke were obtained from BioBank Japan (n=201,800). Colocalization analysis was performed, focusing on the UGT1A1, SLCO1B1, and SLCO1B3 genes, which are the primary loci associated with serum bilirubin levels. RESULTS: Crude 2-sample Mendelian randomization analysis revealed a significant negative association between total bilirubin levels and ischemic stroke. However, in MVMR analyses, only indirect bilirubin demonstrated a significant negative association with ischemic stroke (odds ratio, 0.76; 95% confidence interval, 0.59 to 0.98). Colocalization analysis did not identify a shared causal variant between the 3 genetic loci related to indirect bilirubin and the risk of ischemic stroke. CONCLUSIONS Our study establishes a causal association between higher genetically determined levels of serum indirect bilirubin and reduced risk of ischemic stroke in an Asian population. Future research should include more in-depth analysis of shared genetic variants between indirect bilirubin and ischemic stroke.

OBJECTIVES: Previous research has predominantly focused on total bilirubin levels without clearly distinguishing between direct and indirect bilirubin. In this study, the differences between these forms were examined, and their potential causal relationships with ischemic stroke were investigated. METHODS: Two-sample multivariable Mendelian randomization (MVMR) analysis was employed, extracting summary data on bilirubin from the Korean Cancer Prevention Study-II (n=159,844) and the Korean Genome and Epidemiology Study (n=72,299). Data on ischemic stroke were obtained from BioBank Japan (n=201,800). Colocalization analysis was performed, focusing on the UGT1A1, SLCO1B1, and SLCO1B3 genes, which are the primary loci associated with serum bilirubin levels. RESULTS: Crude 2-sample Mendelian randomization analysis revealed a significant negative association between total bilirubin levels and ischemic stroke. However, in MVMR analyses, only indirect bilirubin demonstrated a significant negative association with ischemic stroke (odds ratio, 0.76; 95% confidence interval, 0.59 to 0.98). Colocalization analysis did not identify a shared causal variant between the 3 genetic loci related to indirect bilirubin and the risk of ischemic stroke. CONCLUSIONS Our study establishes a causal association between higher genetically determined levels of serum indirect bilirubin and reduced risk of ischemic stroke in an Asian population. Future research should include more in-depth analysis of shared genetic variants between indirect bilirubin and ischemic stroke.