The cross-sectional relationship between dietary calcium intake and metabolic syndrome among men and women aged 40 or older in rural areas of Korea

BACKGROUND/OBJECTIVES

Studies conducted in Western populations have suggested that dietary calcium may protect against metabolic abnormalities, but there is little evidence of this effect in Asians, who have relatively low calcium intake. We evaluated the cross-sectional relationship between dietary calcium and metabolic syndrome among Korean men and women aged 40 years and over.

SUBJECTS/METHODS

A total of 6,375 subjects aged 40 years and over and were recruited between January 2005 and February 2010 from the baseline study of the Multi-Rural Communities Cohort Study in Rural Communities (MRCohort). A food frequency questionnaire was used to collect dietary information. Metabolic syndrome was defined using the modified criteria published in the Third Report of the National Cholesterol Education Program Adult Treatment Panel.

RESULTS

Calcium intake was related inversely to metabolic syndrome in women (P-value = 0.0091), but not in men (P = 0.1842). Among metabolic components, high waist circumference (WC) (P = 0.0426) and high blood glucose (P = 0.0027) in women and hypertriglyceridemia (P = 0.0017) in men were inversely correlated with calcium intake. Excluding those who used calcium or multinutrient supplements did not attenuate the relationship between dietary calcium and metabolic abnormalities.

CONCLUSION

Dietary calcium intake from foods may be inversely related to metabolic syndrome, WC, and blood glucose among women in rural areas of Korea.

Dietary Patterns Derived by Cluster Analysis are Associated with Cognitive Function among Korean Older Adults

The objective of this study was to investigate major dietary patterns among older Korean adults through cluster analysis and to determine an association between dietary patterns and cognitive function. This is a cross-sectional study. The data from the Korean Multi-Rural Communities Cohort Study was used. Participants included 765 participants aged 60 years and over. A quantitative food frequency questionnaire with 106 items was used to investigate dietary intake. The Korean version of the MMSE-KC (Mini-Mental Status Examination-Korean version) was used to assess cognitive function. Two major dietary patterns were identified using K-means cluster analysis. The "MFDF" dietary pattern indicated high consumption of Multigrain rice, Fish, Dairy products, Fruits and fruit juices, while the "WNC" dietary pattern referred to higher intakes of White rice, Noodles, and Coffee. Means of the total MMSE-KC and orientation score of the participants in the MFDF dietary pattern were higher than those of the WNC dietary pattern. Compared with the WNC dietary pattern, the MFDF dietary pattern showed a lower risk of cognitive impairment after adjusting for covariates (OR 0.64, 95% CI 0.44-0.94). The MFDF dietary pattern, with high consumption of multigrain rice, fish, dairy products, and fruits may be related to better cognition among Korean older adults.

Understanding school health environment through interviews with key stakeholders in Lao PDR, Mongolia, Nepal and Sri Lanka

Studies on health promoting schools (HPS) in low- and middle-income countries (LMICs) are scarce. To contribute to the development of HPS in these countries, we conducted formative research to understand the school environment in Lao PDR, Mongolia, Nepal, and Sri Lanka. Forty-three teachers, 10 government workers and 5 parents participated in three one-on-one interviews and 14 natural group interviews. Six themes emerged that centered on insufficient resources as reasons for suboptimal health conditions. At the individual level, participants mentioned the deficiency of personal resources to cope with cold weather and poor diet. At the school level, the lack of physical resources such as water purifiers and latrines was discussed. Interviewees also pointed out the schools' overdependence on external resources and therefore the lack of sustainability. Last, the shortage of health services at the school and community level was commonly mentioned. Based on these results, we believe that the basic concept of HPSs should also be applied when working with schools in LMICs. In conclusion, there was a lack of perception of the importance of policy and capacity development programs, which are important in developing HPSs. Therefore, future school health programs should stress improving these elements.

Validation study of candidate single nucleotide polymorphisms associated with left ventricular hypertrophy in the Korean population

Background

Left ventricular hypertrophy (LVH) is a valid predictor for cardiovascular mortality and morbidity regardless of age, gender, and race. The HyperGEN study conducted a genome-wide association study and identified twelve single nucleotide polymorphisms (SNPs) associated with LVH. The aim of this study was to validate these candidate SNPs in the Korean population.

Methods

Among 1637 individuals from the Korean Multi-Rural Communities Cohort Study (MRCohort) of the Korean Genome Epidemiology Study (KoGES), we carried out a linear regression analysis with left ventricular mass index (LVMI) and a logistic regression analysis for LVH status.

Results

The rs4129218 on chromosome 12 tended to be associated with LVM/body surface area (adjusted β = −0.023; p = 0.036) and LVM/height^2.7 (adjusted β = −0.027; p = 0.016), and was marginally protective against LVH after adjustment for age, sex, body mass index, serum creatinine, systolic blood pressure, heart rate and antihypertensive medication (adjusted odds ratio = 0.766 and 0.731; p = 0.027 and 0.007 according to indexation by BSA and height^2.7, respectively).

Conclusions

In the Korean population, the minor allele of rs4129218 had borderline association with lower LVM. This study suggests that rs4129218 on chromosome 12 showed consistent tendency of possibly related loci for LVH independent of ethnic background.

Electronic supplementary material

The online version of this article (doi:10.1186/s12881-015-0158-1) contains supplementary material, which is available to authorized users.

A nonsynonymous SNP in BANK1 is associated with serum LDL cholesterol levels in three Korean populations

Serum levels of lipids, such as cholesterol and triglycerides, are heritable risk factors for cardiovascular disease and targets for therapeutic intervention. Because previous genome-wide association studies (GWASs) did not target functional genetic variants, we employed an alternate approach using nonsynonymous single-nucleotide polymorphisms (SNPs) to identify functional genetic variants associated with the regulation of serum lipid levels. We selected 3667 healthy individuals from a rural community-based cohort (CAVAS; Cardio Vascular disease Association Study) of the Korean Genome and Epidemiology Study project. We analyzed demographic and lifestyle information, lipid measurements and genotypes using the Illumina-1M SNP chip. For genotyping, we isolated 11 558 nonsynonymous SNPs and conducted a linear regression analysis with four lipid traits (total, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterols and triglycerides). Significantly associated SNPs were validated in two independent Korean populations, Korean Association Resource (KARE) (n=4116) and Health Examinee (HEXA) (n=2178). Of the 11 558 SNPs, one SNP (rs3733197) from the CAVAS was significantly associated with serum LDL cholesterols (beta±s.e.=4.67±0.94, P-value=1.0 × 10(-6 and) Bonferroni corrected P-value=0.012). The replication results of HEXA and KARE were beta±s.e.=2.88±1.12, P-value=0.016 and beta±s.e.=1.26±0.97, P-value=0.196, respectively. An overall meta-analysis of the three data sets revealed beta=2.98±0.57, P-value=6.19 × 10(-7). The rs3733197 is located in the coding region of BANK1 (B-cell scaffold protein with ankyrin repeats 1), and the minor allele (A) resulted in the replacement of the Alanine at position 383 with Threonine.

Community-based research on the benign prostatic hyperplasia prevalence rate in Korean rural area

Purpose

We investigated the prevalence rate of benign prostatic hyperplasia (BPH) among Korean males in a rural area through a cross-sectional, community-based epidemiologic survey and analyzed the correlation with epidemiologic factors.

Materials and Methods

A total of 779 males who lived in Yangpyeong County participated in a prostate examination campaign. Targeting these men, we collected the International Prostate Symptom Score (IPSS), medical history, demographic information, serum prostate-specific antigen, and prostate volume as measured by transrectal ultrasonography. The data for 599 participants were analyzed, excluding 180 men who had a possibility of prostate cancer. BPH was defined as an IPSS of 8 points or higher and a prostate volume of 25 mL or more.

Results

The prevalence rate of BPH was 20.0%. The prevalence rate increased with age. There were 2 subjects (4.4%) in the age group of 40-49 years, 18 subjects (10.9%) in the age group of 50-59 years, 44 subjects (22%) in the age group of 60-69 years, and 56 subjects (26.6%) in the age group of over 70 years; this increase with age was statistically significant (p<0.001). In the BPH group, the average IPSS was 14.67±5.95, the average prostate volume was 37.04±11.71 g, and the average prostate-specific antigen value was 1.56±0.88 ng/mL. In the analysis of correlations between the epidemiologic factors and the risk of BPH, smoking was the only statistically significant factor.

Conclusions

The total prevalence rate of BPH in this study was 20.0%, which was a little lower than the rate reported in other cities or rural areas.

Association between living arrangements and depressive symptoms among older women and men in South Korea

PURPOSE

We investigated the relationship between different types of living arrangements and depressive symptoms among older Korean women and men.

METHODS

Data were obtained from a nationally representative cross-sectional health survey conducted in 2009 in South Korea. A total of 60,305 participants (34,172 women and 26,133 men) aged 60 years and older were included in the analysis. The living arrangements were categorised into six types as follows: (1) living with a spouse only; (2) living with a spouse in an extended family; (3) living with a spouse in a nuclear family; (4) living alone; (5) living without a spouse in an extended family; and (6) living without a spouse in a nuclear family. The Korean version of the Center for Epidemiologic Studies Depression Scale was used as the measurement tool for depressive symptoms. We used multiple regression analysis to estimate the effects of living arrangement on depressive symptoms.

RESULTS

A total of 16.8 % of the total study population showed depressive symptoms. Living with a spouse only was the most common type of living arrangement (46.3 %). Women and men living with a spouse only were the least likely to have depressive symptoms. However, living without a spouse in a nuclear family and living alone were most strongly associated with depressive symptoms in women (OR 1.81; 95 % CI 1.64-2.00) and men (OR 2.71; 95 % CI 2.43-3.03), respectively.

CONCLUSIONS

The prevalence of depressive symptoms are associated with the living arrangements of elderly Koreans. There are gender differences in these associations, that may stem from the different demands of social roles and relationships in the family.

Genome-wide association meta-analysis identifies novel variants associated with fasting plasma glucose in East Asians

Fasting plasma glucose (FPG) has been recognized as an important indicator for the overall glycemic state preceding the onset of metabolic diseases. So far, most indentified genome-wide association loci for FPG were derived from populations with European ancestry, with a few exceptions. To extend a thorough catalog for FPG loci, we conducted meta-analyses of 13 genome-wide association studies in up to 24,740 nondiabetic subjects with East Asian ancestry. Follow-up replication analyses in up to an additional 21,345 participants identified three new FPG loci reaching genome-wide significance in or near PDK1-RAPGEF4, KANK1, and IGF1R. Our results could provide additional insight into the genetic variation implicated in fasting glucose regulation.

Differences in gastric mucosal microbiota profiling in patients with chronic gastritis, intestinal metaplasia, and gastric cancer using pyrosequencing methods

BACKGROUND

Helicobacter pylori (H. pylori) infection plays an important role in the early stage of cancer development. However, various bacteria that promote the synthesis of reactive oxygen and nitrogen species may be involved in the later stages. We aimed to determine the microbial composition of gastric mucosa from the patients with chronic gastritis, intestinal metaplasia, and gastric cancer using 454 GS FLX Titanium.

METHODS

Gastric mucosal biopsy samples were collected from 31 patients during endoscopy. After the extraction of genomic DNA, variable region V5 of the 16S rRNA gene was amplified. PCR products were sequenced using 454 high-throughput sequencer. The composition, diversity, and richness of microbial communities were compared between three groups.

RESULTS

The composition of H. pylori-containing Epsilonproteobacteria class appeared to be the most prevalent, but the relative increase in the Bacilli class in the gastric cancer group was noticed, resulting in a significant difference compared with the chronic gastritis group. By analyzing the Helicobacter-dominant group at a family level, the relative abundance of Helicobacteraceae family was significantly lower in the gastric cancer group compared with chronic gastritis and intestinal metaplasia groups, while the relative abundance of Streptococcaceae family significantly increased. In a UPGMA clustering of Helicobacter-dominant group based on UniFrac distance, the chronic gastritis group and gastric cancer group were clearly separated, while the intestinal metaplasia group was distributed in between the two groups. The evenness and diversity of gastric microbiota in the gastric cancer group was increased compared with other groups.

CONCLUSIONS

In Helicobacter predominant patients, the microbial compositions of gastric mucosa from gastric cancer patients are significantly different to chronic gastritis and intestinal metaplasia patients. These alterations of gastric microbial composition may play an important, as-yet-undetermined role in gastric carcinogenesis of Helicobacter predominant patients.

Early adulthood: an overlooked age group in national sodium reduction initiatives in South Korea

BACKGROUND/OBJECTIVES

South Korean's sodium consumption level is more than twice the upper limit level suggested by the WHO. Steep increases in the prevalence of hypertension and cardiovascular disease in Korea necessitate more effective sodium reduction programs. This study was conducted in order to compare sodium intake-related eating behaviors and key psychosocial factors according to age group and gender.

SUBJECTS/METHODS

Using an online survey, a total of 1,564 adults (20-59 years old) considered to be geographically representative of South Korea were recruited and surveyed. The major outcomes were perceived behaviors, knowledge, intentions, and self-efficacy related to sodium intake.

RESULTS

The results show that perceived behavior and level of self-efficacy related to low sodium consumption differed by age and gender. Female participants showed better behavior and intention towards low sodium intake than male counterparts. Young participants in their 20s showed the lowest intention to change their current sodium intake as well as lowest self-efficacy measures.

CONCLUSIONS

Future sodium reduction interventions should be developed with tailored messages targeting different age and gender groups. Specifically, interventions can be planned and implemented at the college level or for workers in their early career to increase their intention and self-efficacy as a means of preventing future health complications associated with high sodium intake.

Characteristics of pleural effusions in systemic lupus erythematosus: differential diagnosis of lupus pleuritis

We investigated the clinical characteristics of pleural effusion in systemic lupus erythematosus (SLE). A prospective analysis of 17 SLE patients with pleural effusion (seven lupus pleuritis, eight transudative effusions and two parapneumonic effusions) was performed. Thirty non-SLE patients with pleural effusion were recruited as controls. A pleural fluid ANA titer ≥1:160 was found in 8/17 (47.1%) SLE patients and none of the 30 non-SLE patients (p = 0.0001). Pleural fluid to serum C3 ratios were significantly lower in SLE than in non-SLE (median (minimum-maximum) 0.29 (0.03-0.43) versus 0.52 (0.26-0.73), p = 0.0002). Among SLE patients, pleural fluid ANA titers ≥1:160 were more frequently found in patients with lupus pleuritis than in those with pleural effusion from causes other than lupus itself (85.7% versus 20.0%, p = 0.0152). Serum CRP levels were significantly increased in patients with lupus pleuritis compared with SLE patients with transudative pleural effusion (2.30 (0.30-5.66) versus 0.7 (0.12-1.47) mg/dl, p = 0.0062). In conclusion, pleural fluid ANA titer and serum CRP levels are significantly increased in lupus pleuritis.

Meta-analysis of genome-wide association studies in East Asian-ancestry populations identifies four new loci for body mass index

Recent genetic association studies have identified 55 genetic loci associated with obesity or body mass index (BMI). The vast majority, 51 loci, however, were identified in European-ancestry populations. We conducted a meta-analysis of associations between BMI and ∼2.5 million genotyped or imputed single nucleotide polymorphisms among 86 757 individuals of Asian ancestry, followed by in silico and de novo replication among 7488-47 352 additional Asian-ancestry individuals. We identified four novel BMI-associated loci near the KCNQ1 (rs2237892, P = 9.29 × 10(-13)), ALDH2/MYL2 (rs671, P = 3.40 × 10(-11); rs12229654, P = 4.56 × 10(-9)), ITIH4 (rs2535633, P = 1.77 × 10(-10)) and NT5C2 (rs11191580, P = 3.83 × 10(-8)) genes. The association of BMI with rs2237892, rs671 and rs12229654 was significantly stronger among men than among women. Of the 51 BMI-associated loci initially identified in European-ancestry populations, we confirmed eight loci at the genome-wide significance level (P < 5.0 × 10(-8)) and an additional 14 at P < 1.0 × 10(-3) with the same direction of effect as reported previously. Findings from this analysis expand our knowledge of the genetic basis of obesity.

The association of radiographic progression with serum R-spondin 1 (RSPO1) levels or Dickkopf-1 (DKK1)/RSPO1 ratios in rheumatoid arthritis patients: clinical evidence for reciprocal inhibition between DKK1 and RSPO1

OBJECTIVES

To investigate the clinical implications of serum levels of R-spondin 1 (RSPO1), a natural antagonist for Dickkopf-1 (DKK1), and of DKK1/RSPO1 ratios in rheumatoid arthritis (RA) patients.

METHOD

Serum DKK1 and RSPO1 levels were measured in 102 RA patients and 39 age- and gender-matched healthy controls. In addition, DKK1 and RSPO1 levels were determined prior to and 3 months after anti-tumour necrosis factor alpha (anti-TNF-α) therapy in 15 RA patients. Clinical and laboratory data and baseline radiographs of the hands and feet were obtained. Serial radiographs were evaluated in 83 RA patients. Radiographic joint damage was assessed by the modified Sharp/van der Heijde score (SHS).

RESULTS

Serum RSPO1 levels were significantly reduced whereas serum DKK1 levels and DKK1/RSPO1 ratios were significantly increased in RA patients compared with controls (all p < 0.0001). Anti-TNF-α treatment significantly suppressed DKK1/RSPO1 ratios (p < 0.01). In contrast to DKK1 or RSPO1 levels, the ratios were significantly associated with erosive disease, elevated acute phase reactants, Disease Activity Score in 28 joints (DAS28) > 3.2, and radiographic progression rate (all p < 0.05). Although the RA patients with radiographic progression exhibited significantly increased DKK1 and reduced RSPO1 levels (p < 0.05), only the DKK1/RSPO1 ratio (log-transformed) was found to be a significant predictor of subsequent radiographic progression [odds ratio (OR) 2.07, p < 0.01].

CONCLUSIONS

In this study, the presence of RSPO1 in the circulation was shown for the first time. Our results suggest that the serum DKK1/RSPO1 ratio represents a better predictor of structural progression than either DKK1 or RSPO1 levels alone in RA patients.

The costs of hepatitis A infections in South Korea

OBJECTIVES:

The incidence of hepatitis A infections among young adults has recently increased in South Korea. Although universal vaccination has often been suggested to mitigate the problem, its rationale has not been well-understood. Estimating the societal costs of hepatitis A infections might support the development of intervention strategies.

METHODS:

We classified hepatitis A infections into eight clinical pathways and estimated the number of occurrences and cost per case for each clinical pathway using claim data from National Health Insurance and several national surveys as well as assumptions based on previous studies. To determine the total costs of a hepatitis A infection, both direct and indirect costs were estimated. Indirect costs were estimated using the human-capital approach. All costs are adjusted to the year 2008.

RESULTS:

There were 30,240 identified cases of hepatitis A infections in 2008 for a total cost of 80,873 million won (2.7 million won per case). Direct and indirect costs constituted 56.2% and 43.8% of the total costs, respectively. People aged 20-39 accounted for 71.3% of total cases and 74.6% of total costs. Medical costs per capita were the lowest in the 0-4 age group and highest in the 20-29 age group.

CONCLUSIONS:

This study could provide evidence for development of cost-effective interventions to control hepatitis A infections. But the true costs including uncaptured and intangible costs of hepatitis A infections might be higher than our results indicate.

The relationship of dietary sodium, potassium, fruits, and vegetables intake with blood pressure among Korean adults aged 40 and older

BACKGROUND/OBJECTIVES

The inverse relationships of combined fruits and vegetables intake with blood pressure have been reported. However, whether there are such relationships with salty vegetables has rarely been investigated in epidemiologic studies. We evaluated the relation of combined and separate intake of fruits, vegetable intakes, and salty vegetables, as well as sodium and potassium, with blood pressure among the middle-aged and elderly populations.

SUBJECTS/METHODS

The present cross-sectional analysis of a prospective cohort baseline survey was performed with 6,283 subjects (2,443 men and 3,840 women) and free of hypertension, diabetes, cardiovascular diseases, and cancer. Dietary data were collected by trained interviewers using food frequency questionnaire.

RESULTS

The significantly inverse linear trend of diastolic blood pressure (DBP) was found in fruits and non-pickled vegetables (81.2 mmHg in the lowest quintile vs 79.0 mmHg in the highest quintile, P for trend = 0.0040) and fruits only (80.9 mmHg in the lowest quintile vs 79.4 mmHg in the highest quintile, P for trend = 0.0430) among men. In contrast, sodium and sodium to potassium ratio were positively related with blood pressure among men (DBP, 78.8 mmHg in the lowest quintile vs 80.6 mmHg in the highest quintile, P for trend = 0.0079 for sodium; DBP, 79.0 mmHg in the lowest quintile vs 80.7 mmHg in the highest quintile, P for trend = 0.0199 and SBP, 123.8 mmHg in the lowest quintile vs 125.9 mmHg in the highest quintile for sodium/potassium). Kimchies consumption was positively related to DBP for men (78.2 mmHg in the lowest quintile vs 80.9 mmHg in the highest quintile for DBP, P for trend = 0.0003). Among women, these relations were not found.

CONCLUSION

Fruits and/or non-pickled vegetables may be inversely, but sodium, sodium to potassium, and Kimchies may be positively related to blood pressure among men.

Harmful and beneficial relationships between alcohol consumption and subclinical atherosclerosis

BACKGROUND AND AIMS

Arterial stiffness and increased intima-media wall thickness are two of the main predictors of cardiovascular disease (CVD). We evaluated whether brachial-ankle pulse wave velocity (baPWV) and common carotid artery intima-media wall thickness (CCA-IMT) are correlated with alcohol consumption in a cross-sectional study among Korean men and women aged 40 years and over.

METHODS AND RESULTS

All 5539 subjects (2121 men and 3418 women) were participants in the Multi-Rural Communities cohort (MRcohort) study, a part of the Korean Genome Epidemiology Study (KoGES). The baPWV was positively correlated with alcohol consumption in men (p for trend <0.0001). Age (middle-aged versus elderly) modified the effect of alcohol consumption on PWV. On the other hand CCA-IMT decreased with alcohol consumption in men. There was no favorable zone of alcohol consumption in terms of baPWV and CCA-IMT. Adjustment for lipid profiles substantially attenuated the relationship between alcohol consumption and CCA-IMT. There was no clear relation between alcohol consumption and baPWV/CCA-IMT in women.

CONCLUSIONS

Along with a linear harmful relationship between alcohol consumption and arterial stiffness in men there may also be a beneficial relationship between alcohol consumption and carotid intima-wall thickness. The effect of alcohol on arterial stiffness may be slightly stronger in elderly men, and the effect of alcohol on CCA-IMT may be mediated by lipid factors.

Elevated brachial-ankle pulse wave velocity is independently associated with microalbuminuria in a rural population

Microalbuminuria is a marker of generalized endothelial dysfunction resulting from arterial stiffness or insulin resistance, and brachial-ankle pulse wave velocity (baPWV) is a good measure of arterial stiffness. We aimed to investigate whether elevated baPWV is independently associated with microalbuminuria. This study included 1,648 individuals aged over 40 who participated in the baseline Multi-Rural Cohort Study conducted in Korean rural communities between 2005 and 2006. Participants were classified into less than 30 mg/g as normoalbuminuria or 30-300 mg/g as microalbuminuriausing urinary albumin creatinine ratio (UACR). The median and Q1-Q3 baPWV values were significantly higher in the microalbuminuric group both in men (1,538, 1,370-1,777 cm/s vs. 1,776, 1,552-2,027 cm/s, P < 0.001) and women (1,461, 1,271-1,687 cm/s vs. 1,645, 1,473-1,915 cm/s, P < 0.001). BaPWV was independently associated with microalbuminuria in both genders after adjusting for pulse rate; fasting blood glucose; triglyceride; homeostatic model assessment insulin resistance (HOMAIR) and, history of hypertension and diabetes. Fasting blood sugar and HOMAIR were judged as having nothing to do with multicolinearity (r = 0.532, P < 0.001). Elevated baPWV was independently associated with microalbuminuria regardless of insulin resistance among rural subjects over 40 yr.

The effect of coffee, tea, and caffeine consumption on serum uric acid and the risk of hyperuricemia in Korean Multi-Rural Communities Cohort

Caffeine, a commonly consumed food constituent, is known to exert beneficial physiological effects in humans. There is a lack of comprehensive population data for the effects of caffeine intake on urate metabolism. Therefore, the aim of this study was to determine whether coffee, tea, and caffeine intake influences serum uric acid and the risk of hyperuricemia in the Korean Multi-Rural Communities Cohort. We enrolled 9,400 participants in this study. An assessment of various dietary intake amounts of substances such as coffee and tea was performed using a food frequency questionnaire. The content of caffeine was calculated from coffee (74 mg/cup) and tea (15 mg/cup) intake information from the past year. Multivariate logistic regression models, multiple linear regression models, and analysis of covariance were applied to identify any association of dietary intake with serum uric acid levels or the risk of hyperuricemia. No trends for coffee, tea, or caffeine intake were found according to each quintile with serum uric acid in males, although there were weak, marginally significant trends between the content of coffee and caffeine intake and serum uric acid level in females (p = 0.07 for both). Tea intake in males and caffeine intake in females were significantly different between non-hyperuricemia and hyperuricemia (p = 0.04 and p = 0.04, respectively). In addition, a significant association of serum uric acid level with tea intake in males (β = 0.0006, p = 0.02) and with tea intake and caffeine intake in females (β = 0.0003, p = 0.04 and β = 0.0006, p = 0.02, respectively) was observed. There was no effect of coffee, tea, or caffeine intake on the risk of hyperuricemia in either males or females. This study suggests that caffeine consumption might have an effect on serum uric acid in females. However, coffee, tea, and caffeine intake amounts were not associated with the risk of hyperuricemia.

Dietary patterns and cognitive function in Korean older adults

PURPOSE

The objectives of this study were to identify major dietary patterns and to investigate the association between dietary patterns and cognitive function in older adults.

METHODS

This is a cross-sectional study. The data from the Korean Multi-Rural Communities Cohort Study, which is a part of the Korean Genome Epidemiology Study, were used. There were 806 (340 men and 466 women) subjects aged ≥ 60 years. Usual dietary intake was assessed using a quantitative food frequency questionnaire with 106 food items. Cognitive function was assessed using the Korean version Mini-Mental State Examination (MMSE-KC). We conducted factor analysis using the principal component analysis method to identify the major dietary patterns. The association between major dietary patterns and cognitive function was investigated by logistic regression analysis.

RESULTS

Three major dietary patterns were identified and assigned descriptive names based on the food items with high loadings: "prudent" pattern, "bread, egg, and dairy" pattern, and "white rice only" pattern. As the white rice only pattern scores increased, a significant decreasing trend for MMSE-KC scores was observed after adjusting for covariates. The bread, egg, and dairy pattern was inversely related to the risk of cognitive impairment, and the white rice only pattern was positively associated with the risk of cognitive impairment.

CONCLUSIONS

This study suggests that specific dietary patterns were significantly associated with cognitive impairment in older adults. In particular, like the white rice only pattern, a rice-centered diet without well-balanced meals may increase the risk of cognitive impairment. However, since our study is a cross-sectional design, the possibility of reverse causality should be considered.

Self-reported snoring and carotid atherosclerosis in middle-aged and older adults: the Korean Multi-Rural Communities Cohort Study

Background

We investigated the relation of self-reported snoring with carotid intima-media thickness (IMT) and plaque in community-dwelling middle-aged and older adults.

Methods

In total, 7330 community-dwelling subjects in the Korean Multi-Rural Communities Cohort Study were included in the analysis. Common carotid artery IMT (CCA-IMT) and plaque were evaluated by high-resolution B-mode ultrasonography. Snoring status was evaluated using a structured interview.

Results

Snorers had a significantly greater average CCA-IMT than non-snorers (0.726 vs 0.713 mm; P < 0.001), after adjusting for age and gender. The odds ratios (OR) for high CCA-IMT (fifth quintile) were significantly higher for snorers than for non-snorers in multivariate-adjusted analysis (OR 1.25, 95% confidence interval [CI] 1.10–1.42). However, there was no significant relationship between snoring and carotid plaques.

Conclusions

Our data suggest that self-reported snoring is significantly associated with increased IMT, but not with the presence of plaques. These findings suggest that early screening and intervention for snoring in the general population are needed to prevent adverse cardiovascular events.

Comparison between an automated device and a manual mercury sphygmomanometer in an epidemiological survey of hypertension prevalence

BACKGROUND

Automated devices (AD) for measuring blood pressure (BP) are gradually replacing mercury sphygmomanometers (MM) in clinical settings. However, the use of ADs in epidemiological surveys has not been established. We investigated the factors associated with measurement differences when using an MM and an AD.

METHODS

Two trained observers took three BP measurements in 454 subjects as part of an epidemiological survey, alternately using an MM and an AD. BP measurement difference was defined as BPMM - BPAD. Alarm reactions (ARs) were calculated by subtracting the third systolic BP (SBP) measurement from the first SBP.

RESULTS

The mean age of subjects was 50.7±15.4 years (n = 454). The mean BPs using the MM and the AD were 119.8±13.9 vs. 119.5±13.6mm Hg in males and 115.0±16.8 vs. 111.6±15.7mm Hg in females for SBP and 77.7±10.4 vs. 74.7±10.4mm Hg in males and 73.2±9.3 vs. 69.9±10.3mm Hg in females for diastolic BP (DBP). Age, gender, arm circumference, and AR were the factors related to the difference. The concordance correlation coefficients for SBP and DBP were 0.8914 (95% confidence interval [CI], 0.8727-0.9102) and 0.8207 (95% CI, 0.7920-0.8494). The kappa values for the diagnosis of hypertension and Joint National Committee 7 BP classification were 0.6538 (0.5436-0.7641) and 0.5703 (0.5055-0.6351), respectively. The diagnostic sensitivity for hypertension was 59.0%.

CONCLUSIONS

Age, gender, arm circumference, and AR were the factors related to the differences. Despite small differences in the mean values, the agreement and reliability were not good enough to recommend the A&D UA-767PC for adoption in epidemiological surveys of hypertension prevalence.

Costs of illness and quality of life in patients with systemic lupus erythematosus in South Korea

OBJECTIVE

To assess the costs of illness, health-related quality of life (HRQOL) and their associated factors in patients with systemic lupus erythematosus (SLE) in South Korea.

METHOD

Two hundred and one patients with SLE were enrolled at the Rheumatology clinic of Seoul National University Hospital. Direct, indirect and total costs and HRQOL were measured using hospital electronic data and face-to-face interview. Socio-demographic and clinical factors associated with cost of illness and HRQOL were analyzed using multiple regression and multivariate logistic regression.

RESULTS

The average total cost of illness was estimated to be KRW 9.82 million (US $ 8993) per year, of which 41.6% was accounted for by direct costs and 58.4% by indirect costs. In multivariate regression, patients with renal involvement and those with depression incurred an average increment in annual total costs of 37.6% (p = 0.050) and 49.1% (p = 0.024), respectively, and an average increment in annual direct costs of 26.4% (p = 0.050) and 43.3% (p = 0.002), respectively, compared with patients without renal involvement and depression, respectively. In addition, disease damage was positively associated with an average increment in annual total and direct costs (55.3%, p = 0.006; 33.3%, p = 0.013, respectively), and the occurrence of indirect costs (OR 2.21, 1.09-4.88). There was no significant difference in HRQOL between patients with and without renal involvement (0.655 vs. 0.693, p = 0.203) CONCLUSION: Renal involvement, depression, and disease damage were major factors associated with higher total and medical costs for patients with SLE in South Korea. Effective treatment of renal disorders and depression may reduce the high economic burden of SLE.

Relationship between nocturnal blood pressure and 24-h urinary sodium excretion in a rural population in Korea

BACKGROUND

The relationship between sodium intake and blood pressure (BP) is affected by many factors such as absolute level of sodium intake, salt sensitivity, and the accuracy or the timing of the BP measurement. There is no epidemiologic study using both ambulatory BP monitoring (ABPM) and 24-h urine sample in a middle-aged general population.

METHODS

In the rural area, Yeojoo County, Gyunggi Province in South Korea, 218 subjects with age between 30 and 59 years old were measured with ABPM and 24-h urine sample. ABPM device was TM2430, and the 24-h urine sample was collected using the aliquot cup. Metabolic syndrome (MetS) score was calculated by the sum of the number of abnormal criteria other than BP.

RESULTS

For both ABPM and 24-h urine sample, 148 subject data was acceptable for the analysis by the creatinine equation and/or the completeness of collection. Age was 47.4 ± 8.3 years (range 30 to 59 years), and female was 85 (57.4%). In multiple linear regression analysis, sodium intake was not an independent factor for casual BPs and daytime BPs whereas sodium intake was an independent factor for nighttime systolic BP (β = 1.625, p = 0.0026) and nighttime diastolic BP (β = 1.066, p = 0.0017). When compared to the lowest quartiles of sodium intake, daytime diastolic BP and nighttime BPs were in the higher three quartile groups.

CONCLUSIONS

Sodium intake was associated not with casual BPs and daytime BPs but with increased nighttime BPs in the middle-aged general population in Korea.