Association between Serum Testosterone Levels and Body Composition among Men 20–59 Years of Age

Introduction. Sex hormones play an important role in the development and maintenance of bone and muscle mass. However, studies regarding serum testosterone levels, osteoporosis, and sarcopenia in men are relatively sparse and have led to contradictory conclusions. Therefore, this study aimed to investigate the association between serum testosterone levels and body composition, including bone mineral density (BMD), appendicular lean mass index (ALMI), and appendicular fat mass index (AFMI), among men 20–59 years of age through a cross-sectional analysis of the National Health and Nutrition Examination Survey. Materials and Methods. Our analysis was based on the data for 3,875 men, 20–59 years of age. Weighted multiple regression analyses were used to estimate the independent association between serum testosterone levels and body composition. Weighted generalized additive models and smooth curve fittings were used to characterize the nonlinear associations between them. Results. The association between the serum testosterone level and lumbar BMD was positive in each multivariable linear regression model. In the model adjusted for age and race, the serum testosterone level was negatively associated with ALMI. However, in the models adjusted for body mass index, this association became positive. In addition, the association between the serum testosterone level and AFMI was negative in each multivariable linear regression model. Conclusion. Our study demonstrated a positive association of serum testosterone level with lumbar BMD and ALMI, and a negative association with AFMI, among men 20–59 years of age, suggesting that increasing testosterone levels may be beneficial to skeletal health in young and middle-aged men with low testosterone levels.

Impact on National Policy on the Hand Hygiene Promotion Activities in Hospitals in Korea

Background: After the Middle East respiratory syndrome coronavirus outbreak in Korea in 2015, the government newly established the additional reimbursement for infection prevention to encourage infection control activities in the hospitals. The new policy was announced in December 2015 and was implemented in September 2016. We evaluated how infection control activities improved in hospitals after the change of government policy in Korea. Methods: Three cross-sectional surveys using the WHO Hand Hygiene Self-Assessment Framework (HHSAF) were conducted in 2013, 2015, and 2017. Using multivariable linear regression model including hospital characteristics, we analyzed the changes in total HHSAF scores according to the survey time. Results: In total, 32 hospitals participated in the survey in 2013, 52 in 2015, and 101 in 2017. The number of inpatient beds per infection control professionals decreased from 324 in 2013 to 303 in 2015 and 179 in 2017. Most hospitals were at intermediate or advanced levels of progress (90.6% in 2013, 86.6% in 2015, and 94.1% in 2017). In a multivariable linear regression model, the total HHSAF scores were significantly associated with hospital teaching status (β coefficient of major teaching hospital, 52.6; 95% CI, 8.9–96.4; P = .018), bed size (β coefficient of 100-bed increase, 5.1; 95% CI, 0.3–9.8; P = .038), and survey time (β coefficient of 2017 survey, 45.1; 95% CI, 19.3–70.9; P = .001). Conclusions: After the national policy implementation, the number of infection control professionals increased, and the promotion of hand hygiene activities was strengthened in Korean hospitals.Funding: NoneDisclosures: None

Impact of national policy on hand hygiene promotion activities in hospitals in Korea

Background After the Middle East respiratory syndrome coronavirus outbreak in Korea in 2015, the Government established a strategy for infection prevention to encourage infection control activities in hospitals. The new policy was announced in December 2015 and implemented in September 2016. The aim of this study is to evaluate how infection control activities improved within Korean hospitals after the change in government policy. Methods Three cross-sectional surveys using the WHO Hand Hygiene Self-Assessment Framework (HHSAF) were conducted in 2013, 2015, and 2017. Using a multivariable linear regression model, we analyzed the change in total HHSAF score according to survey year. Results A total of 32 hospitals participated in the survey in 2013, 52 in 2015, and 101 in 2017. The number of inpatient beds per infection control professionals decreased from 324 in 2013 to 303 in 2015 and 179 in 2017. Most hospitals were at intermediate or advanced levels of progress (90.6% in 2013, 86.6% in 2015, and 94.1% in 2017). In the multivariable linear regression model, total HHSAF score was significantly associated with hospital teaching status (β coefficient of major teaching hospital, 52.6; 95% confidence interval [CI], 8.9 to 96.4; P = 0.018), beds size (β coefficient of 100 beds increase, 5.1; 95% CI, 0.3 to 9.8; P = 0.038), and survey time (β coefficient of 2017 survey, 45.1; 95% CI, 19.3 to 70.9; P = 0.001). Conclusions After the new national policy was implemented, the number of infection control professionals increased, and hand hygiene promotion activities were strengthened across Korean hospitals.

P3693Self-expandable transcatheter aortic valve implantation is associated with frequent periprocedural stroke detected by diffusion-weighted magnetic resonance imaging -Insight from propensity score match

Background Little evidence is available regarding the risk of peri-procedural stroke detected by diffusion-weighted magnetic resonance imaging (DW-MRI) after transcatheter aortic valve implantation (TAVI). Our purpose was to evaluate stroke risk after TAVI using DW-MRI by enrolling consecutive patients who underwent transfemoral TAVI and post-procedural DW-MRI. Methods We prospectively enrolled 113 consecutive patients who underwent transfemoral TAVI and post-procedural DW-MRI. We used balloon-expandable valves as first-line therapy and selected self-expandable valves only for patients with narrow sinotubular junctions or annuli. We set the primary endpoint as the number of high intensity areas (HIA) detected by DW-MRI regardless of the size of the area. To evaluate the risks of the primary endpoint, we employed a multivariable linear regression model, setting the primary endpoint as an objective variable and patient and clinical backgrounds as explanatory variables. In addition, the relationship between valve type and the number of HIAs on DW-MRI was also confirmed by the propensity score matching analysis to evaluate the robustness of the result, using a multivariable linear regression model with the protocol described in the previous manuscript. Shortly, the propensity score was calculated with a logistic regression model by setting the treatment as the response variable and baseline characteristics and procedural information that were significantly different between 2 groups (balloon expandable and self-expandable) as explanatory variables, which included age, estimated glomerular filtration rate, oversizing rate, and BAV before THV deployment. Results Median patient age was 84 years, and 36.3% were men. Ninety-three patients underwent balloon-expandable TAVI and 20 underwent self-expandable TAVI. Symptomatic stroke occurred in 6 (5.3%) whereas asymptomatic stroke occurred in 59 (52.2%) patients. The incidence of symptomatic and total stroke was higher in patients who underwent self-expandable TAVI than those who underwent balloon-expandable TAVI (30.0% vs 0.0%, p<0.001 and 90.0% vs 50.5%, p=0.001, respectively). A multivariable linear regression model demonstrated an increased primary endpoint when self-expandable TAVI was performed (p<0.001). The other covariates had no significant relationship to the primary endpoint. Akaike information criterion-based stepwise statistical model selection revealed that valve type was the only explanatory variable for the best predictive model. This result was also confirmed with the propensity score matching analysis (estimate, 2.359; 95% CI, 0.426–4.292; p=0.019) after adjustments of propensity score, in which 28 patients were matched (n=14 in each group). Conclusions Self-expandable valves were associated with increased numbers of HIA on DW-MRI after TAVI in patients with severe aortic stenosis.

Multivariable Regression Equivalent Model of Interconnected Active Distribution Networks Based on Boundary Measurement

With the increasing complexity of the active distribution network (ADN) due to distributed generation (DG) integration, together with the electricity market evolution, the traditional ADN is divided into multiple areas to operate independently. Due to technical problems or business privacy, the internal network regional control center cannot grasp the changes of the external regional network in time. In order to accurately reflect the distribution network operation state, a multivariable regression equivalent model is proposed in this paper. Firstly, the external network is made equivalent to a multi-port Norton model. The multivariable linear regression model is then derived based on the equivalent distribution network, and the regression model variables are constructed using boundary node information collected by the measurement equipment. Finally, the maximum likelihood estimation (MLE) is used to estimate the parameters of the multivariable linear regression model. Furthermore, case studies demonstrate the effectiveness and robustness of the proposed method, and detailed information of external ADN is unnecessary, except for the boundary node information. The proposed method can also be applied for three-phase unbalanced ADN efficiently.