The Korean urban rural elderly cohort study: study design and protocol.

BACKGROUND: Korea is one of the fastest aging countries and is expected to become a super-aged society within 12 years. The Korean Urban Rural Elderly (KURE) study was developed to evaluate the epidemiological characteristics and establish the prevention and management of major disorders of the elderly in Korea. METHODS/DESIGN: The KURE study is a community-based prospective cohort study on health, aging, and common geriatric disorders of Korean elderly persons aged at least 65 years. To construct a cohort reflecting both urban and rural areas, we selected 2 representative communities in the country. To establish multidisciplinary approaches to geriatric health, this study was performed by researchers in the divisions of geriatrics, preventive medicine, endocrinology, and sociology. The baseline examinations began in 2012; the study will follow more than 4,000 elderly Koreans over 10 years. The first and second follow-up health examinations will be performed every 4 years. Every 2 years after each health examination, inter-assessment interview will be conducted to improve participant retention. DISCUSSION: The KURE study will provide longitudinal epidemiologic data on health, aging, and common geriatric disorders of the elderly in Korea. This is a comprehensive, multidisciplinary study of the elderly with respect to biological, physical, socio-economic, and environmental factors. The results of this study will contribute to improve public health and welfare policies for the aging society in Korea.

Low muscle mass, low muscle function, and sarcopenia in the urban and rural elderly.

Health outcomes of the elderly vary between rural and urban areas. Sarcopenia is diagnosed as loss of muscle strength or impaired physical performance, namely "low muscle function" and low muscle mass. Outcomes of low muscle mass and low muscle function are not equal. This study aimed to investigate the prevalence of low muscle mass, low muscle function, and sarcopenia in rural and urban populations and to determine whether regional differences were associated with each of these components. Participants aged ≥ 69 years (n = 2354) were recruited from three urban districts and one rural district in Korea. Low muscle mass was defined by appendicular lean mass using bioelectrical impedance analysis. Low muscle function was defined by handgrip strength and 5-chair stand test. Sarcopenia was defined as low muscle mass plus low muscle function. The prevalence of low muscle function (53.7% vs. 72.8%), and sarcopenia (16.3% vs. 24.4%) were higher in the rural elderly population. Rural residence was associated with low muscle function (OR 1.63; 95% CI 1.13-2.37, P = 0.009), but not with low muscle mass (OR 0.58; 95% CI 0.22-1.54, P = 0.271) or with sarcopenia (OR 1.13; 95% CI 0.63-2.00, P = 0.683). Interventions to detect and improve low muscle function in rural elderly population are needed.

The effects of polymorphisms in methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR), and methionine synthase reductase (MTRR) on the risk of cervical intraepithelial neoplasia and cervical cancer in Korean women.

The purpose of the study was to investigate the association between cervical cancer risk and single-nucleotide polymorphisms (SNPs) in three one-carbon metabolism genes, methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR), and methionine synthase reductase (MTRR) in Korean women. Twelve SNPs were identified in MTHFR, MTR, and MTRR in the 927 case-control samples, which included 165 cervical intraepithelial neoplasia 1 (CIN1), 167 cervical intraepithelial neoplasia 2 and 3 (CIN2/3), 155 cervical cancer patients, and 440 normal controls. The frequencies of the genotypes and haplotypes were assessed in the controls, CINs, and cervical cancers. Individual carriers of the variant allele C of MTHFR A1298C (rs1801131) had a 0.64-fold [95% confidence interval (CI): 0.42-0.98] decreased risk for CIN2/3 compared with common homozygotes. However, no significant association was found between most other variants and cervical cancer risk. The results also identified an increased CIN1 risk in carriers with at least one copy of haplotype 3 in the MTHFR gene (odds ratio, 1.88; 95% CI: 1.03-3.42). In conclusion, there was no significant association between most SNPs in MTHFR, MTR, or MTRR and the risk of CIN and cervical cancer in Korean women. In addition, there was no significant association of MTHFR haplotypes with risk of CIN2/3 and cervical cancer.

Intakes of vitamin A, C, and E, and beta-carotene are associated with risk of cervical cancer: a case-control study in Korea.

Cervical cancer is one of the most common gynecological malignancies in Korea, although the incidence has been declining in recent years. This study explored whether antioxidant vitamin intakes influenced the risk of cervical cancer. The association between antioxidant vitamin intakes and cervical cancer risk was calculated for 144 cervical cancer cases and 288 age-matched, hospital-based controls using unconditional logistic regression models. Cases reported statistically lower mean dietary intakes of vitamin A, beta -carotene, and vitamin C than did controls. Total intakes of vitamins A and E, which included both dietary and supplement intake, were also lower in cases. Those patients in the highest quartiles of dietary vitamin A, beta -carotene, and vitamin C intakes had statistically significantly lower cervical cancer risks than those in the lowest quartiles for vitamin A, beta -carotene, and vitamin C: odds ratio (OR) = 0.36 [95% confidence interval (CI) = 0.19-0.69), OR = 0.48 (CI = 0.26-0.88), and OR = 0.36 (CI = 0.18-0.69), respectively. Total intakes of vitamins A, C, and E were strongly inversely associated with cervical cancer risk: OR = 0.35 (CI = 0.19-0.65), OR = 0.35 (CI = 0.19-0.66), and OR = 0.53 (CI = 0.28-0.99), respectively. The findings support a role for increased antioxidant vitamin intake in decreasing the risk of cervical cancer. These associations need to be assessed in large prospective studies with long-term follow-up.

Preoperative levels of plasma micronutrients are related to endometrial cancer risk.

OBJECTIVE: To examine the relation between the plasma concentration of antioxidant micronutrients and endometrial cancer risk in Korean women. DESIGN: Hospital-based case-control study. SETTING: Seven tertiary medical institutes in Korea. POPULATION: Incidence of 28 endometrial cancer cases were identified and 140 age-matched controls selected for the same period. METHODS: Preoperative plasma concentrations of beta-carotene, lycopene, zeaxanthin plus lutein, retinol, alpha-tocopherol, and gamma-tocopherol were measured by reverse-phase, gradient high-pressure liquid chromatography. Conditional logistic regression was used to evaluate micronutrient effect after adjustment for body mass index (BMI), menopause, parity, oral contraceptive use, smoking status, and alcohol consumption status. MAIN OUTCOME MEASURES: Effect of micronutrients on endometrial cancer risk. RESULTS: The mean concentration of plasma beta-carotene (p=0.001), lycopene (p=0.008), zeaxanthin plus lutein (p=0.031), retinol (p=0.048), and gamma-tocopherol (p=0.046) were significantly lower in endometrial cancer patients than in controls. Plasma levels of beta-carotene (p for trend=0.0007) and lycopene (p for trend=0.007) were inversely associated with endometrial cancer risk across tertiles. Women in the highest tertile of plasma beta-carotene and lycopene had a 0.12-fold (95% confidence intervals (CIs) 0.03-0.48) and 0.15-fold (95% CIs 0.04-0.61) decreased risk of endometrial cancer compared to women in the lowest tertile, respectively. Other micronutrients such as zeaxanthin plus lutein (p for trend=0.142), retinol (p for trend=0.108), alpha-tocopherol (p for trend=0.322), and gamma-tocopherol (p for trend=0.087) showed no association with endometrial cancer risk. CONCLUSIONS: Plasma levels of beta-carotene and lycopene are inversely associated with the risk of endometrial cancer in Korean women.

Association between changes in systolic blood pressure and incident diabetes in a community-based cohort study in Korea.

An association between hypertension and diabetes has been reported; however, the temporal relationship of blood pressure changes and incident diabetes has not been fully investigated in the general population. We examined whether increasing blood pressure is associated with the risk of developing diabetes among community-dwelling Korean adults. This study included 2225 participants (859 men and 1366 women) aged 27-87 years from the Korean Genome Epidemiology Study. The participants were free of diabetes and cardiovascular disease at baseline. Incident diabetes was defined as fasting blood glucose⩾126 mg dl-1 or hemoglobin a1c ⩾6.5% (48 mmol mol-1) at follow-up examination and/or a physician's diagnosis of diabetes during the follow-up period. The effects of the baseline level and change in blood pressure on the risk of incident diabetes were assessed by multivariate logistic regression analysis. During the mean follow-up of 2.6 years, new-onset diabetes was observed in 5.0% (43/859) of the men and 3.4% (47/1366) of the women. In the multivariate model, the baseline systolic blood pressure was not significantly associated with incident diabetes (adjusted odds ratio 0.93 per 10 mmHg, P=0.747). However, an increase in systolic blood pressure during the follow-up period was independently associated with incident diabetes (adjusted odds ratio 5.53 per 5 mmHg per year, P=0.002) after adjusting for the baseline blood pressure and other potential confounders. Increasing blood pressure, but not a high baseline blood pressure, was independently associated with the risk of diabetes in Korean adults.

Associations of changes in body mass index with all-cause and cardiovascular mortality in healthy middle-aged adults.

BACKGROUND: Conflicting data exist regarding the association of body mass index (BMI) changes with all-cause and cardiovascular (CV) mortality. The current study investigated the association between changes in BMI and all-cause, CV, and non-CV mortality in a large cohort of middle-aged adults. METHODS: A total of 379,535 adults over 40 years of age without pre-existing CV disease or cancer at baseline were enrolled to undergo a series of at least three health examinations of biennial intervals. Changes in BMI between baseline, midpoint follow-up, and final health examination during mean 9.3 years were defined according to the pattern of BMI change as follows: stable, sustained gain, sustained loss, and fluctuation. The relationship between BMI change category and mortality was assessed by multivariate Cox regression reporting hazard ratio (HR) with 95% confidence interval (95% CI). RESULTS: During a mean follow-up of 10.7 years for mortality, 12,378 deaths occurred from all causes, of which 2,114 were CV and 10,264 were non-CV deaths. Sustained BMI gain was associated with the lower risk of all-cause (HR 0.89, 95% CI: 0.83-0.95), CV (HR 0.84, 95% CI 0.72-0.98), and non-CV mortality (HR 0.90, 95% CI 0.84-0.96) compared with stable BMI. Conversely, sustained BMI loss (HR 1.25, 95% CI 1.19-1.32) and fluctuation (HR 1.13, 95% CI 1.08-1.19) displayed a higher risk of all-cause mortality compared with stable BMI, which was mainly attributable to the increase in non-CV mortality. CONCLUSION: Sustained BMI gains were associated with reduced risk of all-cause, CV, and non-CV mortality in middle-aged healthy adults.

Association of metabolic syndrome and 25-hydroxyvitamin D with cognitive impairment among elderly Koreans.

AIM: Metabolic syndrome and vitamin D deficiency are prevalent in older adults, and are considered risk factors for cognitive impairment. We investigated the combined effects of MetS and serum 25-hydroxyvitamin D (25[OH]D) levels on cognitive function in older adults. METHODS: We studied 2940 participants aged ≥65 years from the Korean Urban Rural Elderly cohort study. Metabolic syndrome was defined according to the updated Adult Treatment Panel III criteria. Serum 25(OH)D levels were categorized into four groups: <25, 25-49, 50-74 and ≥75 nmol/L. Cognitive function was assessed using the Mini-Mental State Examination. RESULTS: Participants with cognitive impairment had higher metabolic syndrome prevalence and lower serum 25(OH)D levels than those without cognitive impairment. In univariate analysis, both metabolic syndrome and low 25(OH)D levels were associated with cognitive impairment. These associations remained unchanged after adjusting for potential confounders including age, sex, season and education. In addition, participants with metabolic syndrome and low 25(OH)D had significantly increased odds for cognitive impairment (odds ratio 3.06, 95% CI 1.61-5.80) when compared with those with no metabolic syndrome and high 25(OH)D. CONCLUSIONS: Metabolic syndrome was associated with cognitive impairment, and this risk was synergistically increased when metabolic syndrome was combined with low 25(OH)D. A focus on individuals with metabolic syndrome and low 25(OH)D might be helpful to identify older adults who are at risk of cognitive impairment. Geriatr Gerontol Int 2017; 17: 1069-1075.

Low Normal TSH levels are Associated with Impaired BMD and Hip Geometry in the Elderly.

Subclinical hyperthyroidism is known to be associated with the risk of fractures in elderly people. However, there are few studies assessing whether low normal thyroid-stimulating hormone (TSH) levels affect bone density and geometry. Here, we aimed to assess the influence of the TSH level on bone mineral density (BMD) and geometry in elderly euthyroid subjects. This was a cross-sectional cohort study. A total of 343 men and 674 women with euthyroidism were included and analyzed separately. The subjects were divided into tertiles based on the serum TSH level. The BMD and geometry were measured using dual-energy X-ray absorptiometry and a hip structural analysis program. Multiple regression analysis was used to compute the odds ratios of osteoporosis in the lower TSH tertile group and the association between geometry parameters and the TSH level. We found that the femoral neck and total hip BMDs were lower in the lower TSH tertile group. In women, the cross-sectional area and cortical thickness of the femur were negatively associated with the TSH level in all three regions (the narrow neck, intertrochanter, and femoral shaft); however, in men, these geometry parameters were significantly associated with the TSH level only in the intertrochanter region. The buckling ratio, a bone geometry parameter representing cortical instability, was significantly higher in the lower TSH tertile group in all three regions in women, but not in men. Our results indicated that lower TSH levels in the euthyroid range are related to lower BMD and weaker femoral structure in elderly women.

Genetic polymorphism of ESR1 rs2881766 increases breast cancer risk in Korean women.

PURPOSE: We performed a case-control study to evaluate the association of genetic polymorphisms of estrogen-metabolizing enzyme genes and estrogen receptor genes with breast cancer risk according to age group and subtypes in Korean women. METHODS: Breast cancer patients (n = 830) and the hospital healthy controls (n = 390) with both clinical information and SNP data were included in the study. Age was divided into three groups: premenopausal under 35 years (n = 64), premenopausal over 35 years (n = 456), and postmenopausal women (n = 310), respectively. Tumor subtype was classified into four subtypes: luminal A, luminal B, HER2-overexpressing, and triple-negative, respectively. Genotyping of the selected SNPs in ESR1, ESR2, CYP1A1, CYP1B1, and COMT was conducted using the VeraCode Golden Gate Genotyping Assay Technology. Multiple logistic regression models (dominant, recessive, and additive) were applied to determine the odds ratio, 95% confidence interval, and p value. RESULTS: ESR1, rs2881766, rs2077647, rs926778, and rs2273206 polymorphisms increased breast cancer risk, and rs3798377 decreased the risk in overall patients. The association between SNP genotype and breast cancer risk was varied according to age groups and tumor subtypes. For age subgroups, rs2881766 increased breast cancer risk in the all three age groups, and rs926778 increased the risk in premenopausal over 35 years women and in postmenopausal women. For the tumor subtypes, rs2881766 increased breast cancer risk manly in luminal A, HER2-overexpressing, and triple-negative subtypes except for luminal B subtype, and rs926778 increased the risk in luminal A and triple-negative subtypes. Rs3798577 decreased the risk in luminal B and triple-negative subtypes. CONCLUSION: The results showed that ESR1 rs2881766 polymorphism increased breast cancer risk and rs3798377 decreased the risk in Korean women. Because of wide variation of the association between SNP genotype and breast cancer risk according to age group and tumor subtypes, further studies such as a large-scale cohort study need for validation and test of biologic significance.

[Two cases of systemic amyloidosis presenting with abnormalities in liver function tests].

Systemic amyloidosis results from the deposition of insoluble, fibrous amyloid proteins. It occurs mainly in the extracellular spaces of multiple organs and tissues including the kidney, heart, and liver. Although amyloid deposition in the liver is common in patients with systemic amyloidosis, clinically apparent liver disease is relatively rare. Indeed, most patients with systemic amyloidosis manifest only minimal to moderate hepatomegaly and trivial abnormalities in liver function tests. Recently, we experienced two cases of patients who presented with abnormalities in liver function tests and hepatomegaly as manifestations of systemic amyloidosis. We report these cases with a review of the relevant literatures.

Simultaneous quantification of opiates and effect of pigmentation on its deposition in hair.

In forensic toxicology, the abuse of various opiate preparations, such as raw opium and heroin, is of interest since the metabolic pathways of these opiates overlap. Although the pharmaco(toxico)kinetics in hair is not clearly understood, melanin is thought to play a key part in the incorporation and distribution of drugs and metabolites in hair. Therefore, in the present study, a simultaneous quantification method for the determination of codeine, morphine, norcodeine, normorphine and 6-acetylmorphine (6-AM) in hair was developed in order to analytically diagnose chronic users of opiates including morphine and codeine preparations, raw opium and heroin. Furthermore, the effect of hair pigmentation on the distribution of opiates in hair was investigated using lean Zucker rats with both dark grey and white hair on the same body. Opiates were extracted using 0.1 M hydrochloric acid followed by solid phase extraction. The extracts were derivatized with N-methyl-N-(trimethylsilyl)trifluoroacetamide and analyzed using gas chromatography/mass spectrometry (GC/MS). The method was fully validated and applied to the animal study. In conclusion, the current study demonstrates that codeine, morphine and their metabolites were successfully determined in both pigmented and non-pigmented hair. However, the melanin content plays an important role in the degree of incorporation of morphine, codeine and their metabolites into hair.

Structure of the Cdt1 C-terminal domain: conservation of the winged helix fold in replication licensing factors.

In eukaryotic replication licensing, Cdt1 plays a key role by recruiting the MCM2-7 complex onto the origin of chromosome. The C-terminal domain of mouse Cdt1 (mCdt1C), the most conserved region in Cdt1, is essential for licensing and directly interacts with the MCM2-7 complex. We have determined the structures of mCdt1CS (mCdt1C_small; residues 452 to 557) and mCdt1CL (mCdt1C_large; residues 420 to 557) using X-ray crystallography and solution NMR spectroscopy, respectively. While the N-terminal 31 residues of mCdt1CL form a flexible loop with a short helix near the middle, the rest of mCdt1C folds into a winged helix structure. Together with the middle domain of mouse Cdt1 (mCdt1M, residues 172-368), this study reveals that Cdt1 is formed with a tandem repeat of the winged helix domain. The winged helix fold is also conserved in other licensing factors including archaeal ORC and Cdc6, which supports an idea that these replication initiators may have evolved from a common ancestor. Based on the structure of mCdt1C, in conjunction with the biochemical analysis, we propose a binding site for the MCM complex within the mCdt1C.

[Assessment of quality of life and associated factors in patients with chronic viral liver disease].

BACKGROUND/AIMS: The aim of this study was to measure health related quality of life (HRQOL) in patients with chronic viral hepatitis or cirrhosis and to determine factors associated with more severe impairment. METHODS: We conducted a cross-sectional study in which we documented patients' demographic and clinical characteristics and measured their HRQOL using the Korean version of Short Form-36. A total of 375 patients were enrolled in the study. We compared patients' HRQOL with that of 750 participants in a control group and assessed the association of HRQOL impairment with clinical parameters. RESULTS: In all except two domains (physical functioning, bodily pain) of SF-36, HRQOL scores were significantly lower in the patient group than in the control group (p<0.001). The difference was more prominent in those domains reflective of mental, rather than physical, health. When patient group was classified as noncirrhosis, Child A, B, or C according to modified Child-Pugh classification, severe liver disease was associated with a lower HRQOL score. Interestingly, scores of domains reflective of mental health were decreased from the early stage of disease (noncirrhosis or Child-Pugh A). Those of domains reflective of physical health, however, were decreased only in advanced stages of disease (Child-Pugh B or C). There are weak but significant correlations between SF-36 scores and age, serum albumin, serum bilirubin, and prothrombin time, but no correlation with histologic activity, transaminase level, disease duration, virus type (HBV or HCV) and HBV DNA level. CONCLUSIONS: Compared with the control group, patients with chronic viral hepatitis or cirrhosis showed substantial impairment of HRQOL, which is further affected by worsening disease severity. More concern about HRQOL should be warranted in the evaluation of health change due to disease progression or therapeutic trial.