Ji Hyun Moon

Implication of Sarcopenia and Sarcopenic Obesity on Lung Function in Healthy Elderly: Using Korean National Health and Nutrition Examination Survey

Previous studies have demonstrated a positive association between obesity and decreased lung function. However, the effect of muscle and fat has not been fully assessed, especially in a healthy elderly population. In this study, we evaluated the impact of low muscle mass (LMM) and LMM with obesity on pulmonary impairment in healthy elderly subjects. Our study used data from the Korea National Health and Nutrition Examination Survey from 2008 to 2011. Men and women aged 65 yr or older were included. Muscle mass was measured by dual-energy X-ray absorptiometry. LMM was defined as two standard deviations below the sex-specific mean for young healthy adults. Obesity was defined as body mass index ≥ 25 kg/m2. The prevalence of LMM in individuals aged over 65 was 11.9%. LMM and pulmonary function (forced vital capacity and forced expiratory volume in 1 second) were independently associated after adjusting for age, sex, body mass index, smoking status, alcohol consumption, and frequency of exercise. LMM with obesity was also related to a decrease in pulmonary function. This study revealed that LMM is an independent risk factor of decreased pulmonary function in healthy Korean men and women over 65 yr of age.

Visceral-to-subcutaneous fat ratio as a predictor of the multiple metabolic risk factors for subjects with normal waist circumference in Korea

Purpose Visceral obesity has been recognized as a predictor of metabolic risk factors. However, few studies have evaluated the metabolic risks in subjects with normal waist circumference (WC). We aimed to examine if the visceral-to-subcutaneous fat ratio (VSR) has diagnostic value to identify multiple metabolic risk factors in subjects with normal WC, compared with visceral fat area (VFA) and subcutaneous fat area (SFA). Methods This is a cross-sectional study in which we have compared mean VFA, SFA, and VSR according to each metabolic risk factor. We performed a receiver operating characteristic (ROC) curve analysis for VFA, SFA, and VSR to assess their accuracy in picking out two or more non-adipose factors for metabolic syndrome. Results For each metabolic risk factor, mean VSRs were significantly different between groups (risk-absent group vs risk-present group) in men and women, except for men with low high-density lipoprotein. However, mean VFAs and SFAs showed no significant differences between groups. VSR showed superior diagnostic values in predicting at least two non-adipose metabolic risk factors in men and similar diagnostic value in women. Areas under ROC curves for VSR and VFA were 0.705 and 0.649 in men (P=0.028) and 0.798 and 0.785 in women (P=0.321). Conclusion For men with a normal WC, VSR appeared to effectively predict the presence of multiple metabolic risk factors. Thus, VSR may serve as an indicator for identifying men who have a normal WC and multiple metabolic risk factors.

Association between Homocysteine and Bone Mineral Density according to Age and Sex in Healthy Adults

Background There are several studies about the relationship between serum homocysteine levels and bone mineral density (BMD), but the results are varied, and the studies are limited in Korea. In our study, the relationship between serum homocysteine levels and BMD by part according to age and sex is investigated. Methods From March 2012 to July 2015, the 3,337 healthy adults who took a medical examination were recruited. Subjects filled in the self-recording type questionnaire and physical examination, blood test, BMD of lumbar spine and femur were measured. After sorting by aging (≤49 year old, 50-59 year old, ≥60 year old) and sex, the results were adjusted with age and body mass index (BMI) and the relationship between serum homocysteine levels and BMD by lumbar spine and femur was analyzed by multiple regression analysis. Results As results of analysis, with the adjustment with age and BMI, all age groups of men had no significant relationship between log-converted serum homocysteine levels and BMD. In women aged under 50, there were significantly negative relationships at lumbar spine (β=-0.028, P=0.038), femur neck (β=-0.062, P=0.001), and total hip (β=-0.076, P<0.001), but there was no significant relationship in other age groups (50-59 year old and ≥60 year old). Conclusions As the serum homocysteine levels increased in women aged under 50, BMD of the lumbar spine and femur decreased, and correlations between homocysteine and BMD were different by sex and age.

Association between Hemoglobin Level and Bone Mineral Density in Korean Adults

Background Low bone mineral density (BMD) increases fracture risk. Anemia is highly prevalent. Some studies suggested that anemia is an independent risk factor for osteoporosis. The aim of this study was to evaluate the association between hemoglobin (Hb) level and BMD in Korean adults. Methods This study was based on data from the Korea National Health and Nutrition Examination Survey 2008 to 2011. Propensity score-matching was performed to establish a dataset for analysis. Regression analyses were used to evaluate the association between Hb and BMD. Mean BMD scores were compared between normal and anemia groups, and among normal, anemia with low ferritin, and anemia without low ferritin groups. Results There were partial positive associations between Hb and BMD in men, but negative associations in women. The normal group had lower mean BMD scores than the anemia group in men. However, the anemia group had higher whole-body and lumbar-spine BMD scores than the normal group in women. In a comparison of the three groups, the anemia without low ferritin group had the lowest all-site BMD scores in men and women. However, the anemia with low ferritin group had the highest all-site BMD scores in women. In postmenopausal women, the anemia without low ferritin group had the lowest all-site BMD scores. In premenopausal women, the anemia with low ferritin group had the highest whole-body BMD scores. Conclusions This study found that Hb and anemia status were associated with BMD scores. However, the associations were different according to sex. This may be due to the etiology of anemia or low Hb levels.

Evaluation of the Predictive Index for Osteoporosis as a Clinical Tool to Identify the Risk of Osteoporosis in Korean Men by Using the Korea National Health and Nutrition Examination Survey Data

Background We previously proposed the Predictive Index for Osteoporosis as a new index to identify men who require bone mineral density measurement. However, the previous study had limitations such as a single-center design and small sample size. Here, we evaluated the usefulness of the Predictive Index for Osteoporosis using the nationally representative data of the Korea National Health and Nutrition Examination Survey. Methods Participants underwent bone mineral density measurements via dual energy X-ray absorptiometry, and the Predictive Index for Osteoporosis and Osteoporosis Self-Assessment Tool for Asians were assessed. Receiver operating characteristic analysis was used to obtain optimal cut-off points for the Predictive Index for Osteoporosis and Osteoporosis Self-Assessment Tool for Asians, and the predictability of osteoporosis for the 2 indices was compared. Results Both indices were useful clinical tools for identifying osteoporosis risk in Korean men. The optimal cut-off value for the Predictive Index for Osteoporosis was 1.07 (sensitivity, 67.6%; specificity, 72.7%; area under the curve, 0.743). When using a cut-off point of 0.5 for the Osteoporosis Self-Assessment Tool for Asians, the sensitivity and specificity were 71.9% and 64.0%, respectively, and the area under the curve was 0.737. Conclusion The Predictive Index for Osteoporosis was as useful as the Osteoporosis Self-Assessment Tool for Asians as a screening index to identify candidates for dual energy X-ray absorptiometry among men aged 50–69 years.

Association of Coffee Consumption with Sarcopenia in Korean Elderly Men: Analysis Using the Korea National Health and Nutrition Examination Survey, 2008–2011

Background Sarcopenia is an age-related loss of muscle mass and strength. Coffee has antioxidant and anti-inflammatory properties that have been shown to be inversely related to the mechanism of sarcopenia. While there have been some studies on the effect of coffee on sarcopenia in animals, studies on the topic in humans are rare. Therefore, we investigated this relationship in elderly Korean men. Methods The cross-sectional data were derived from the 2008–2011 Korea National Health and Nutrition Examination Survey. After applying the exclusion criteria, the study sample consisted of 1,781 men who were at least 60 years of age. Study participants were identified as having sarcopenia if their appendicular skeletal muscle mass divided by height squared was less than two standard deviations below the gender-specific mean of this value for young adults. Daily coffee consumption amounts were categorized as <1 cup, 1 cup, 2 cups, and ≥3 cups. Results Compared to the group of individuals who drank less than one cup of coffee a day, people who consumed at least 3 cups (adjusted odds ratio, 0.43; 95% confidence interval, 0.20 to 0.94) showed significantly decreased sarcopenia; however, the decrease was not significant when the daily coffee consumption was 1 or 2 cups. In multivariate logistic regression models, significant associations were observed between sarcopenia and coffee consumption (P for trend=0.039). Conclusion The results of this study suggest that consuming at least 3 cups of coffee per day was associated with a lower prevalence of sarcopenia in elderly Korean elderly men.