Association of muscle strength with cardiovascular risk in Korean adults: Findings from the Korea National Health and Nutrition Examination Survey (KNHANES) VI to VII (2014-2016).

There are few existing studies that examine the association between muscle strength and cardiovascular disease (CVD) risk stratified by sex. Evaluation of the handgrip strength is a simple, quick, and inexpensive method to measure muscle strength. This study assessed the association of handgrip strength with the risk of CVD in the Korean general population.Data were derived from a subset of an ongoing nationally representative survey: the Korea National Health and Nutrition Examination Survey (KNHANES), 2014 to 2016, which included 8576 participants aged 40 to 79 years (men: 3807; women: 4769). Individual CVD risk was evaluated by calculating the atherosclerotic cardiovascular disease (ASCVD) risk score and the Framingham risk score (FRS) in subjects aged 40 to 79 years without prior CVD.Multivariate linear regression analysis revealed a significant inverse association (in both men and women) between relative handgrip strength and cardiovascular risk factors, including blood pressure, levels of fasting glucose and triglycerides, waist circumstance, FRS, high sensitivity C-reactive protein levels, and ASCVD risk. A significant positive association between relative handgrip and a low level of high density cholesterol levels in both men and women was identified. In both men and women, subjects in the lowest quartile of handgrip strength had an increased risk of CVD compared with those within the highest quartile (odds ratio range 2.05-3.03).The results of this study suggest that increased handgrip is associated with a lower degree of cardiovascular risk in both men and women. Longitudinal studies are needed to examine the association between muscle strength and cardiovascular risk.

The association between muscular strength and depression in Korean adults: a cross-sectional analysis of the sixth Korea National Health and Nutrition Examination Survey (KNHANES VI) 2014.

BACKGROUND: There are conflicting researches on the relationship between muscular strength and depression, the most common mental illness. There is no study of relationship between muscular strength and depression using national data from young adults to seniors. For example, there has not been a study done explaining mediating pathways among the influences of handgrip strength on depression. Here, we conducted survey for the association between relative handgrip strength and depression and explain mediated pathways for quality of life. METHODS: A cross-sectional study was administered to 4298 Korean adult subjects, aged 19-80 years, based on the 6th Korean National Health and Nutrition Examination Survey (KNHANES VI) of 2014. Handgrip strength reported as the average with each hand. The relative handgrip strength is defined as the handgrip strength divided by the body mass index (BMI). We performed analysis for all subjects and age groups (young adult, middle-aged, and elderly). We analyzed the association using multivariate linear regression and logistic regression. We also conducted mediation analysis for quality of life, which was measured by the EuroQol Five-Dimension Questionnaire (EQ5D). RESULTS: After adjusting for covariates, handgrip strength was inversely associated with the PHQ-9 score (P < 0.05). The odds ratios (OR) of depression symptoms were statistically significant for participants in the first and second quartile of handgrip strength compared to those with the highest quartile in entire sample, young adult, middle-aged, and elderly. There was about a 50% mediation effect of EQ5D in the relationship between handgrip strength and depression. CONCLUSIONS: Using a large national sample, our results found that lower handgrip strength is associated with an increased risk of depression in Korean adult (young adult, middle-aged, and elderly). Our results suggest that increasing muscular strength may prevent depression in Korean adults.

Association between muscle strength and type 2 diabetes mellitus in adults in Korea: Data from the Korea national health and nutrition examination survey (KNHANES) VI.

Diabetes mellitus (DM) is a significant chronic disease, and health burden from DM is increasing. Recently, studies on the relationship between handgrip strength, which is a measuring tool for muscle strength, and type 2 DM were published. However, the results have been conflicting. In addition, few studies that used data from adults in Korea have been conducted. Thus, this study aimed to identify the association between handgrip strength as well as type 2 DM and insulin resistance in adults using data from the Korea National Health and Nutrition Examination Survey (KNHANES) 2014 to 2015. Inflammation is a condition affecting the muscle strength of individuals with type 2 DM; therefore, its mediating effects were also examined.We included 8208 participants aged between 19 and 80 years who had undergone a handgrip test and had received information about type 2 DM. General linear and binary logistic regression models were used to examine the association between handgrip strength and type 2 DM variables. In addition, mediation analysis was conducted to estimate the role of inflammation in the relationship between handgrip strength and type 2 DM.After adjusting for age, sex, education, alcohol consumption, lifetime smoking, obesity, and aerobic physical activity, handgrip strength was inversely associated with fasting glucose, HbA1c, and fasting insulin levels as well as the homeostasis model assessment of insulin resistance (HOMA-IR) score. Multivariable logistic regression analyses showed that handgrip strength was significantly inversely associated with type 2 DM and insulin resistance. The high-sensitivity C-reactive protein (hs-CRP), an inflammation-related biomarker, mediated approximately 10% of the association between handgrip strength and type 2 DM.Using large, well-defined, nationally representative cross-sectional data on adults in Korea, we found that handgrip strength, which is an indicator of muscle strength, was associated with type 2 DM.

Acute health effects of accidental chlorine gas exposure.

OBJECTIVES: This study was conducted to report the course of an accidental release of chlorine gas that occurred in a factory in Gumi-si, South Korea, on March 5, 2013. We describe the analysis results of 2 patients hospitalized because of chlorine-induced acute health problems, as well as the clinical features of 209 non-hospitalized patients. METHODS: We analyzed the medical records of the 2 hospitalized patients admitted to the hospital, as well as the medical records and self-report questionnaires of 209 non-hospitalized patients completed during outpatient treatment. RESULTS: Immediately after the exposure, the 2 hospitalized patients developed acute asthma-like symptoms such as cough and dyspnea, and showed restrictive and combined pattern ventilatory defects on the pulmonary function test. The case 1 showed asthma-like symptoms over six months and diurnal variability in peak expiratory flow rate was 56.7%. In case 2, his FEV1 after treatment (93%) increased by 25% compared to initial FEV1 (68%). Both cases were diagnosed as chlorine-induced reactive airways dysfunction syndrome (RADS) on the basis of these clinical features. The most frequent chief complaints of the 209 non-hospitalized patients were headache (22.7%), followed by eye irritation (18.2%), nausea (11.2%), and sore throat (10.8%), with asymptomatic patients accounting for 36.5%. The multiple-response analysis of individual symptom revealed headache (42.4%) to be the most frequent symptom, followed by eye irritation (30.5%), sore throat (30.0%), cough (29.6%), nausea (27.6%), and dizziness (27.3%). CONCLUSIONS: The 2 patients hospitalized after exposure to chlorine gas at the leakage site showed a clinical course corresponding to RADS. All of the 209 non-hospitalized patients only complained of symptoms of the upper airways and mucous membrane irritation.

Factors affecting the burden on caregivers of stroke survivors in South Korea.

OBJECTIVE: To elucidate the factors related to the caregiver burden in stroke survivors in Seoul, Korea. DESIGN: Cross-sectional study. SETTING: Outpatient clinic of a university hospital in Korea. PARTICIPANTS: We randomly selected 340 stroke patients and evaluated them for 3 years poststroke. Among them, 147 caregivers and patients were finally interviewed. INTERVENTIONS: Patients' demographic data, neurologic symptoms, depression, emotional incontinence, and Modified Rankin Scale (MRS) score were assessed. In addition, primary caregivers' demographic data, hours of care per day, relationship with the patients, health status, anxiety and depression, and the presence of alternative caregivers were assessed. MAIN OUTCOME MEASURES: Caregiver burden was evaluated with the Sense of Competence Questionnaire, which has 3 subdomains with a total of 27 items. RESULTS: Caregiver burden score was high as compared with reports from Western society. Patient factors related to the burden scores were being unemployed ( P <.05), the presence of diabetes mellitus ( P <.05), aphasia ( P <.01), dysarthria ( P <.05), dysphagia ( P <.01), cognitive dysfunction ( P <.01), severe MRS score ( P <.01), emotional incontinence ( P <.05), and depression ( P <.01). Caregiver factors related to high burden scores were being female ( P <.05), unemployment ( P <.01), being daughters-in-law ( P <.01), anxiety ( P <.01), depression ( P <.01), and long caregiving hours ( P <.05). On multivariate analysis, the most significant predictor for overall caregiver burden was caregiver anxiety followed by patient MRS score and caregivers being daughters-in-law. Caregiver depression, current employment status, and patient depression were also factors related to their burden. CONCLUSIONS: Caregiver anxiety, patient physical deficits, and caregivers being daughter-in-law are important factors related to the caregiver burden in our population. Strategies to reduce caregiver burden should be developed based on understanding of these factors.