E-cigarette and cigarette use among cancer survivors versus general population: a case-control study in Korea.

PURPOSE: Although successful smoking cessation after cancer diagnosis is important, research on e-cigarette use and smoking behavior among cancer survivors (CS) is limited. This study compared cigarette and e-cigarette use among CS and non-cancer populations in Korea. METHODS: This study analyzed the 2013-2018 National Health and Nutrition Survey data to investigate e-cigarette use and smoking behavior among Korean CS. The data were categorized into 1260 CS and 5040 non-cancer populations using the propensity score matching method. A multiple logistic regression was conducted among CS who previously used cigarettes or e-cigarettes to evaluate factors influencing successful cessation. RESULTS: Regarding conventional smoking, the proportion of ex-smokers was higher (25.2% versus 19.9%) than current smokers (6.7% versus 10.6%) in the CS group than in the propensity matched non-cancer population (PMNCP) (p < 0.001). However, ever use of e-cigarettes did not differ between them (2.4% versus 2.7%, p = 0.529). Successful cessation, defined as not using either cigarettes or e-cigarettes, correlated with problem drinking (OR 0.442, 95% CI 0.207-0.940), depression (OR 0.276, 95% CI 0.087-0.872), and cancer sites. CS of stomach, liver, colorectal, and lung cancer maintained higher successful smoking cessation rates than PMNCP. CONCLUSIONS: Korean CS had a higher cessation rate than PMNCP regarding conventional smoking; however, there was no difference in e-cigarette use. IMPLICATIONS FOR CANCER SURVIVORS: In Korea, some CS continue to use e-cigarettes, and physicians should focus on helping them quit. Individualized and timely interventions should be provided for both cigarette and e-cigarette users, considering factors influencing successful cessation.

Association between hand grip strength and impaired health-related quality of life in Korean cancer survivors: a cross-sectional study.

OBJECTIVES: To assess the association between hand grip strength (HGS) and health-related quality of life (HRQoL) among Korean cancer survivors. DESIGN: Population-based cross-sectional study. SETTING: A nationally representative population survey data (face-to-face interviews and health examinations were performed in mobile examination centres). PARTICIPANTS: A total of 1037 cancer survivors (person with cancer of any type who is still living) with available data on HGS and HRQoL in the sixth and seventh Korea National Health and Nutrition Examination Surveys (2014-2017). PRIMARY OUTCOME MEASURES: Prevalence of impaired HRQoL by HGS. RESULTS: Among 1037 cancer survivors (60.7% women, mean age=62.2 years), 19.2% of them had weak HGS according to gender-specific cut-off values (lowest quintile<29.7 kg in men and <19.7 kg in women). In the study population, the most common cancer site was the stomach, followed by the thyroid, breast, colorectal and cervix. Individuals with weak HGS showed statistically significantly increased impairment in all five dimensions of the EuroQoL-5 dimension (EQ-5D) compared with those in patients with normal HGS. In a multinomial logistic regression analysis, impaired HRQoL (some or extreme problem in EQ-5D) was significantly reduced in each dimension of the EQ-5D, except for anxiety/depression, when HGS was increased. The OR for impaired HRQoL ranged from 0.86 to 0.97 per 1 kg increase in HGS in four dimensions (mobility, self-care, usual activity and pain/discomfort). CONCLUSIONS: Weak HGS was associated with impaired HRQoL in cancer survivors. Future longitudinal studies are needed to confirm the causality between HGS and HRQoL in cancer survivors.

Immunogenicity and Safety of Trivalent Split Influenza Vaccine in Healthy Korean Adults with Low Pre-Existing Antibody Levels: An Open Phase I Trial.

PURPOSE: A phase I clinical trial was conducted to evaluate the immunogenicity and safety of newly developed egg-cultivated trivalent inactivated split influenza vaccine (TIV) in Korea. MATERIALS AND METHODS: The TIV was administered to 43 healthy male adults. Subjects with high pre-existing titers were excluded in a screening step. Immune response was measured by a hemagglutination inhibition (HI) assay. RESULTS: The seroprotection rates against A/California/7/2009 (H1N1), A/Perth/16/2009 (H3N2) and B/Brisbane/60/2009 were 74.42% [95% confidence interval (CI): 61.38-87.46], 72.09% (95% CI: 58.69-85.50), and 86.05% (95% CI: 75.69-96.40), respectively. Calculated seroconversion rates were 74.42% (95% CI: 61.38-87.46), 74.42% (95% CI: 61.38-87.46), and 79.07% (95% CI: 66.91-91.23), respectively. There were 25 episodes of solicited local adverse events in 21 subjects (47.73%), 21 episodes of solicited general adverse events in 16 subjects (36.36%) and 5 episodes of unsolicited adverse events in 5 subjects (11.36%). All adverse events were grade 1 or 2 and disappeared within three days. CONCLUSION: The immunogenicity and safety of TIV established in this phase I trial are sufficient to plan a larger scale clinical trial.

Population pharmacokinetic analysis of piperacillin in burn patients.

Piperacillin in combination with tazobactam, a ß-lactamase inhibitor, is a commonly used intravenous antibiotic for the empirical treatment of infection in intensive care patients, including burn patients. The purpose of this study was to develop a population pharmacokinetic (PK) model for piperacillin in burn patients and to predict the probability of target attainment (PTA) using MICs and concentrations simulated from the PK model. Fifty burn patients treated with piperacillin-tazobactam were enrolled. Piperacillin-tazobactam was administered via infusion for approximately 30 min at a dose of 4.5 g (4 g piperacillin and 0.5 g tazobactam) every 8 h. Blood samples were collected just prior to and at 1, 2, 3, 4, and 6 h after the end of the infusion at steady state. The population PK model of piperacillin was developed using NONMEM. A two-compartment first-order elimination PK model was finally chosen. The covariates included were creatinine clearance (CLCR), day after burn injury (DAI), and sepsis. The final PK parameters were clearance (liters/h) (equal to 16.6 × [CLCR/132] + DAI × [-0.0874]), central volume (liters) (equal to 25.3 + 14.8 × sepsis [0 for the absence or 1 for the presence of sepsis]), peripheral volume (liters) (equal to 16.1), and intercompartmental clearance (liters/h) (equal to 0.636). The clearance and volume of piperacillin were higher than those reported in patients without burns, and the terminal half-life and PTA decreased with the increased CLCR. Our PK model suggests that higher daily doses or longer durations of infusion of piperacillin should be considered, especially for burn patients with a CLCR of ≥ 160 ml/min.

Saturable human neopterin response to interferon-α assessed by a pharmacokinetic-pharmacodynamic model.

BACKGROUND: In this study, we developed a pharmacokinetic (PK)- pharmacodynamic (PD) model of a new sustained release formulation of interferon-α-2a (SR-IFN-α) using the blood concentration of IFN-α and neopterin in order to quantify the magnitude and saturation of neopterin production over time in healthy volunteers. The SR-IFN-α in this study is a solid microparticular formulation manufactured by spray drying of a feeding solution containing IFN-α, a biocompatible polymer (polyethylene glycol) and sodium hyaluronate. METHODS: The full PK and PD (neopterin concentration) datasets from 24 healthy subjects obtained after single doses of 9, 18, 27 and 36 MIU of subcutaneous SR-IFN-α were used to build the mixed-effect model using NONMEM (version 7.2) with the GFORTRAN compiler. RESULTS: A one-compartment model with first-order elimination and a mixture of zero- and first-order absorption was chosen to describe the PK of SR-IFN-α. The time-concentration profile of neopterin, the PD marker, was described by a turnover model combined with a single transit compartment. The saturable pattern of the neopterin response blurring the dose-response relationship of SR-IFN-α was addressed by introducing the concept of the EC50 increasing over time. CONCLUSIONS: The PK-PD model of SR-IFN-α developed in this study has presented a quantitative tool to assess the time-course of a saturable neopterin response in humans.