Decreased muscle strength and/or depression with aging are emerging as important public health concerns in both developed and developing countries. This study investigated the effects of low handgrip strength (HGS) and depression on the risk of all-cause mortality in Korean older adults. Data from 13,901 Korean adults (57% women) who participated in the 2008 baseline survey and completed the 2011 follow-up assessments were used. In total, the current findings showed that individuals with depression only and individuals with low HGS plus depression had significantly higher risks of all-cause mortality (hazard ratio (HR) = 1.366, 95% confidence interval (CI) = 1.033–1.807, p = 0.029 and HR = 1.961, 95% CI = 1.409–2.736, p < 0.001, respectively) even after adjustments for all the measured covariates, compared with individuals with high HGS plus no depression (HR = 1). Gender-stratified analysis showed that men with depression only and men with depression plus low HGS had significantly higher risks of all-cause mortality (HR = 1.376, 95% CI =1.029–1.841, p = 0.031 and HR = 1.861, 95% CI = 1.306–2.651, p = 0.001, respectively) even after adjustments for all the measured covariates, compared with individuals with no depression plus high HGS (HR = 1). In women, however, the joint effect of depression and low HGS only remained significant at borderline (HR = 2.603, 95% CI = 0.981–6.908, p = 0.055) when adjusted for all the confounders. The current finding suggested that depression and low HGS were significantly and synergistically associated with the increased risk of premature death from all causes in the Korean geriatric population.

Background. Obesity and physical inactivity are associated with higher prevalence of cardiovascular disease (CVD). Objective. This study investigated the association between obesity and carotid intima-media thickness (CIMT) stratified by physical activity (PA) in Korean office workers. Methods. Data obtained from 914 office workers aged 21-60 years (347 women) were used. Resting blood pressures, body mass index (BMI), and waist-to-height ratio (WHtR) were measured. PA was assessed using the international physical activity questionnaire. CIMT was assessed with a carotid artery ultrasonography. Logistic regression analysis was used to estimate the odds ratio (OR) and 95% confidence interval (CI) of obesity stratified by weekly PA for an abnormally increased CIMT. Results. Logistic regression analyses showed that those who were overall obese (OR=2.50, 95% CI=1.60-3.91, P<0.001) or central obese (OR=2.08, 95% CI=1.29-3.40, P=0.003) had significantly higher estimated risks of having an abnormally increased CIMT even after adjustments for age, sex, smoking, alcohol consumption, resting blood pressures, and history of hypertension, diabetes, and hyperlipidemia, as compared with those who were not overall or central obese (OR=1). A multivariate linear regression suggested that age (P<0.001), sex (P=0.002), hypertension (P=0.014), smoking (P=0.054), BMI (P<0.001), and physical activity (P=0.011) were important determinants of abnormally elevated CIMT in this study population. Conclusion. The current findings suggest that the risk of obesity for an abnormally increased CIMT is significantly modulated by demographics as well as lifestyle-related risk factors including smoking and physical inactivity in Korean office workers.

Background: The association between physical activity (PA) and all-cause mortality may be modulated by potential confounders. Aim: To investigate the association between weekly PA and all-cause mortality in a population-based prospective study. Subjects and methods: The study sample included Korean older adults aged 60 years and older who participated in baseline assessments (n = 15 416) in 2008 and completed follow-up visits in 2011 (n = 14,976). Primary outcome was 3-year all-cause mortality. Results: Compared with sufficiently active individuals (with Hazard Ratio (HR) = 1), completely inactive and insufficiently active individuals had a significantly higher risk of all-cause mortality (HR = 2.086, 95% CI = 1.639–2.655, p < 0.00 and HR = 1.644, 95% CI = 1.013–2.668, p = 0.044, respectively), even after adjustments for age and sex, health-related behaviour factors (i.e. smoking, alcohol intake and nutritional risk), cognitive impairment and components of frailty phenotype (i.e. involuntary weight loss, exhaustion and slowness). In addition, the inverse association between PA and all-cause mortality is differently modulated by potential confounders, including age, sex, smoking, depressive symptoms, cognitive impairment and involuntary weight loss. Conclusion: PA was inversely and independently associated with all-cause mortality in Korean older adults.

This study examined the relationship of low appendicular skeletal muscle mass and low muscle function with depressive symptoms in Korean older adults. Community-dwelling Korean older adults aged 65 years and older (n = 521) participated in this study. Appendicular muscle mass (ASM) and muscle function (MF) scores were assessed using dual-energy X-ray absorptiometry (DXA) scanning and sit-to-stand mean power based on a 30 s chair stand test, respectively. Depressive symptoms were evaluated using the Korean form of the Center for Epidemiologic Studies Depression Scale. Logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) of depressive symptoms according to ASM- and MF-based subgroups; normal ASM/normal MF, low ASM/normal MF, normal ASM/low MF, and low ASM/low MF. The prevalence of depressive symptoms was 21.3% in all patients: 20.7% in women and 21.5% in men. Compared to the normal ASM/normal MF participants (OR = 1), the risk of depressive symptoms rose incrementally in subjects with low ASM/normal MF (OR = 2.963, p = 0.019), normal AMS/low MF (OR = 3.843, p = 0.002), and low ASM/low MF (OR = 7.907, p < 0.001), respectively. The current findings suggest that the coexistence of low ASM and low MF is significantly and independently associated with an increased risk for depressive symptoms, with dynapenia having a stronger relationship.

Background: To investigate the association between involuntary weight loss (IWL) and late-life depression (LLD) in a population-based cohort study. Methods: Data (N=6945) obtained from the 2008 baseline and 2011 follow-up assessments of the Living Profiles of Older People Survey in Korea were used. Changed body weight between the 2008 and 2011 was classified into stable weight (<-5% ~ <+5%), lightweight loss (≥-5% ~ <-10%), moderate weight loss (≥-10%), lightweight gain (+≥5 ~ <+10%), and moderate weight gain (≥+10%). Results: Compared to the stable weight group, the moderate weight loss group had a higher risk of LLD (odds ratio=1.99, 95% confidence interval=1.61-2.46, P<0.001) even after adjustments for covariates, including age, BMI, education, income, life of solitude, smoking, physical activity, dependent aging, comorbidity, and cognitive function. Conclusion: IWL is significantly associated with LLD in Korean older adults, implying the prognostic importance of IWL for presenting mental health issues later in life.