The healthy adherer effect is a phenomenon in which patients who adhere to medical therapies tend to pursue health-seeking behaviors. Although the healthy adherer effect is supposed to affect health outcomes in patients with coronary artery disease, evaluation of its presence and extent is not easy. This study aimed to assess the relationship between medication adherence and lifestyle modifications and health-related quality of life among post-acute myocardial infarction (AMI) patients. A cross-sectional study was conducted in 417 post-AMI patients who underwent percutaneous coronary intervention (PCI). Patients were recruited from 11 university hospitals from December 2015 to March 2016 in South Korea. Details regarding socio-demographic factors, six health behaviors (low-salt intake, low-fat diet and/or weight-loss diet, regular exercise, stress reduction in daily life, drinking in moderation, and smoking cessation), medication adherence using the Modified Morisky Scale (MMS), and HRQoL using the Coronary Revascularization Outcome Questionnaire (CROQ) were surveyed in a one-on-one interview. In the univariate logistic analysis, sex (female), age (≥70 years), MMS score (≥5), and CROQ score were associated with adherence to lifestyle modification. In the multiple logistic analysis, a high MMS score (≥5) was associated with adherence to lifestyle modification after adjusting for sex, age, marital status, education, and family income (adjusted odds ratio [OR] = 11.7, 95% confidence interval [CI] = 1.5–91.3). After further adjusting for the CROQ score, the association between high MMS score and adherence to lifestyle modification was significant (adjusted OR = 11.5, 95% CI = 1.4–93.3). Adherence to medication was associated with adherence to lifestyle modification, suggesting the possible presence of the healthy adherer effect in post-AMI patients. After further adjusting for HRQoL, the association remained. To improve health outcome in post-AMI patients, early detection of patients with poor adherence to medication and lifestyle modification and motivational education programs to improve adherence are important. In addition, the healthy adherer effect should be considered in clinical research, in particular, in studies evaluating the effects of therapies on health outcomes.

Many firefighters suffering from traumatic events while on duty participate in the work force. However, the impact of work-related traumatic events on work performance is unclear. To address this issue, we administered a work-related traumatic event experience survey, the health-related work limitations questionnaire, the Korea Depression Scale, and the World Health Organization quality of life assessment to firefighters from four cities in Korea. The health-related work limitations questionnaire measured limitations in their ability to perform three specific work demands—physical, psychosocial, and environmental. Of 685 firefighters enrolled in the study, 618 (90.2%) were included in the final analyses. Their mean age ± standard deviation (SD) was 41.1 ± 8.0 years and mean employment period ± SD was 163.0 ± 101.2 months. A large percentage of participants reported they had experienced work-related traumatic events. Among the firefighters, the total work limitation prevalence was 21.5%, 16.8% of them were limited in their abilities to perform physical work demands, 15.5% were limited in performing psychosocial work demands, and 13.8% were limited in their abilities to function without difficulty within the ambient work environment. Based on multivariable logistic regression, with having work-related traumatic event experience of a threat or injury to self, the odds ratio (OR) of having work limitations in physical (OR = 3.32, 95% CI = 1.17–9.41), psychosocial (OR = 3.05, 95% CI = 1.08–8.61), environmental (OR = 4.89, 95% CI = 1.66–14.40) work demands, and total work limitation (OR = 3.73, 95% CI = 1.44–9.68) increased significantly. With experiences of treating fatalities or injured patients, the OR of total work limitation increased significantly (OR = 2.07, 95% CI = 1.09–3.91). We demonstrated a relationship between the firefighters’ exposure to work-related traumatic events and their work limitations. A professional care management system for firefighters to prevent and manage work-related traumatic events should be developed in order to protect and improve their performance ability.

Purpose: The purpose of this study was to evaluate the correlation between muscle strength and knee symptoms (pain, stiffness, and functional limitation) regardless of the presence of radiologic knee osteoarthritis (RKOA) in community-dwelling elderly. Patients and methods: This cross-sectional study used data from the Namgaram-2 cohort. The Namgaram-2 cohort consisted of participants living in three rural communities. Such participants were included for studies on activity limitation due to age-related musculoskeletal disorders including knee osteoarthritis, osteoporosis, and sarcopenia. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), a health assessment tool for patients with arthritis in lower extremities, was used to assess health-related quality of life (HRQOL). Muscle strengths were measured by knee strength (by using the isokinetic dynamometer) and hand grip strength. Results: The WOMAC pain of Kallgren–Lawrence (K/L) grade < 2 was correlated with age, grip strength, nutrition status, and knee extension 180 peak torque. The WOMAC pain of K/L grade ≥ 2 was correlated with age, nutrition status, and knee extension 60 peak torque. The WOMAC stiffness of K/L grade < 2 was correlated with having a spouse, nutrition status, and knee extension 60 peak torque. The WOMAC stiffness of K/L grade ≥ 2 was correlated with knee extension 60 peak torque. The WOMAC function of K/L grade < 2 was correlated with age, grip strength, osteoporosis, nutrition status, and knee extension 180 peak torque. The WOMAC function of K/L grade ≥ 2 was correlated with age, nutrition status, and knee extension 60 peak torque. Conclusion: Muscle strength as measured by grip strength and knee extension was statistically significantly correlated with the WOMAC scores in patients with knee symptoms regardless of whether radiologic signs of knee osteoarthritis were observed.

It is well-known that post-traumatic stress disorder (PTSD) among firefighters contributes to their job-related stress. However, the relationship between burnout and PTSD in firefighters has rarely been studied. This study therefore explored the association between burnout and its related factors, such as trauma and violence, and PTSD symptoms among firefighters in Korea. A total of 535 firefighters participated in the Firefighter Research on Enhancement of Safety & Health study at 3 university hospitals from 2016 to 2017. The 535 participants received a baseline health examination, including questionnaires assessing their mental health. A Web-based survey was also conducted to collect data on job-related stress, history of exposure to violence, burnout, and trauma experience. The associations among burnout, its related factors, and PTSD symptoms were investigated using structural equation modeling. Job demands (β=0.411, p<0.001) and effort-reward balance (β=-0.290, p<0.001) were significantly related to burnout. Burnout (β=0.237, p<0.001) and violence (β=0.123, p=0.014) were significantly related to PTSD risk. Trauma (β=0.131, p=0.001) was significantly related to burnout; however, trauma was not directly associated with PTSD scores (β=0.085, p=0.081). Our results show that burnout and psychological, sexual, and physical violence at the hands of clients directly affected participants' PTSD symptoms. Burnout mediated the relationship between trauma experience and PTSD.

Background: The rapid increase in the elderly population in Korea is associated with an expanded burden of health problems. The purpose of this study was to investigate the association between frailty and physical disability among Koreans using the frailty index, which was developed to assess health conditions in elderly people. Methods: We included 503 elderly people from the Namgaram-II cohort. We used the Korean version of the Kaigo-Yobo checklist as our frailty assessment tool. For the disability assessment tool, we used the Korean version of the 12-item World Health Organization Disability Assessment Schedule (WHODAS-12). We fit multiple linear regression models for men and women for each section. Our models also included variables for musculoskeletal diseases that are known to be associated with frailty, such as sarcopenia, osteoporosis, and radiologic knee osteoarthritis. Results: After correcting for social demographic characteristics, blood profiles, high blood pressure, and diabetes, the Kaigo-Yobo results showed a significant difference in frailty between men (1.53 ± 0.74) and women (2.60 ± 0.77), and WHODAS-12 also showed a significant difference between men (6.59 ± 5.08) and women (15.99 ± 5.70). After correcting for social demographic characteristics, blood profiles, high blood pressure, and diabetes, Kaigo-Yobo and WHODAS-12 were significantly associated with each other among both men (β = 2.667) and women (β = 3.200) (p < 0.001). Conclusions: The study results show an association between frailty and disability among elderly people in rural areas. Therefore, prevention should occur at the pre-frailty stage of a person’s life to prevent further disability. Also, disability welfare programs should be provided to elderly people who present with frailty.

Firefighters have a high risk of developing cardiovascular and mental disorders due to their physical and chemical environments. However, in Korea, few studies have been conducted on environmental risk of firefighters. The Firefighter Research on the Enhancement of Safety and Health (FRESH) study aimed to discover the risk factors for cardiovascular disease and mental disorders among firefighters. Former and current firefighters were recruited from three university hospitals. A total of 1022 participants completed baseline health examinations from 2016 to 2017. All participants were scheduled for follow-ups every 2 years. Baseline health survey, laboratory testing of blood and urine samples, blood heavy metal concentration, urine polycyclic aromatic hydrocarbons (PAHs) metabolites, stress-related hormone test, natural killer cell activity, as well as physical and mental health examinations that focused on cardiovascular and mental disorders, were conducted. In addition, 3 Tesla (3T) brain magnetic resonance imaging (MRI) and neuropsychological tests were also performed to investigate structural and functional changes in the brains of 352 firefighters aged >40 years or new hires with less than 1 year of service.