The factors associated with Vitamin D deficiency in community dwelling elderly in Korea.

BACKGROUND/OBJECTIVES: Recent studies showed vitamin D deficiency is linked to chronic diseases in addition to skeletal metabolism which could threaten the elderly. We analyzed health conditions and socio-demographic factors associated with vitamin D deficiency in community dwelling people aged 65 years and older. SUBJECTS/METHOD: Data from the Korea National Health and Nutrition Examination Survey (KNHANES) 2010 to 2012 were obtained. A total of 2,687 subjects aged 65 years and older were participated. The cutoff value of the Vitamin D deficiency was considered as serum 25-hydroxyvitamin D [25(OH)D] ≤ 20 ng/mL (50 nmol/L). RESULTS: The overall prevalence rate of vitamin D deficiency in the elderly was 62.1%. The factors such as female, obesity, metabolic syndrome, current smoker, and skipping breakfast were positively associated with vitamin D deficiency, but high intensity of physical activity and more than 9 hours of sleep duration were negatively associated with vitamin D deficiency (all P < 0.05). CONCLUSIONS: It is important that health professions know that the factors proved in this study are connected to vitamin D deficiency thus provide information and intervention strategies of vitamin D deficiency to old aged people.

A cohort study of incident microalbuminuria in relation to HOMA-IR in Korean men.

BACKGROUND: Despite the previous studies showing the relationship between microalbuminuria and insulin resistance, longitudinal effect of insulin resistance on development of microalbuminuria is not clearly identified in non-diabetic population. METHODS: One thousand six hundred three non-diabetic Korean men without microalbuminuria in 2005 had been followed up for the development of microalbuminuria until 2010. Microalbuminuria was evaluated by urine-albumin creatinine ration, and insulin resistance was evaluated by homeostasis model assessment of insulin resistance (HOMA-IR). Cox proportional hazards model was used to estimate the risk for microalbuminuria according to the tertile of HOMA-IR. RESULTS: During 5465.8 person-y of average follow-up, microalbuminuria developed in 76 (4.7%) participants. Incidence of microalbuminuria increased in proportion to the level of HOMA-IR (tertile 1: 3.0%, tertile 2: 4.1%, tertile 3: 7.1%, P<0.001). When the 1st tertile of HOMA-IR was set as reference, hazard ratios and 95% confidence interval were 1.15 (0.56-2.35) and 2.07 (1.05-4.09) for those in the 2nd and 3rd tertiles of HOMA-IR, even after adjusting multiple covariates, respectively (P for linear trend=0.054). CONCLUSIONS: Increased insulin resistance was a predictor of microalbuminuria in Korean men.

Associations between lipid measures and metabolic syndrome, insulin resistance and adiponectin. - Usefulness of lipid ratios in Korean men and women -.

BACKGROUND: Several reports have raised the possibility that newly addressed lipid measures might be superior to the traditional ones for cardiovascular risk prediction. However, data on the associations between these lipid measures with metabolic syndrome (MetS) is limited. METHODS AND RESULTS: A cross-sectional study of participants in routine health examinations was performed. The associations between lipid measure variables (total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), TC/HDL-C, LDL-C/HDL-C, TG/HDL-C ratio and non-HDL-C) and MetS, insulin resistance (IR) by homeostatic model assessment (HOMA) and adiponectin were analyzed in 6,546 participants (3,820 men; mean age 46.0+/-9.2 years in men, 44.6+/-9.5 years in women). In multivariable adjusted regression analysis, the 3 lipid ratios of TC/HDL-C, LDL-C/HDL-C and TG/HDL-C showed significant association with the number of MetS components, HOMA and log adiponectin level in both men and women without MetS (P<0.001, respectively), though these relations were weaker in participants with MetS. The mean levels of the lipid ratios also associated with increasing numbers of the MetS components, quartiles of HOMA and adiponectin. CONCLUSIONS: Lipid ratios of TC/HDL-C, LDL-C/HDL-C and TG/HDL-C, as well as TG and HDL, were consistently associated with MetS and IR in participants without MetS. Lipid ratios might be used as integrated and simple lipid measures.