A prospective association between dietary folate intake and type 2 diabetes risk among Korean adults aged 40 years or older: the Korean Multi-Rural Communities Cohort (MRCohort) Study.

It has not been well established whether dietary folate intake reduces the risk of diabetes development. We aimed to clarify the prospective association between dietary folate intake and type 2 diabetes (T2D) risk among 7333 Korean adults aged 40 years or older who were included in the Multi-Rural Communities Cohort. Dietary folate intake was estimated from all 106 food items listed on a FFQ, not including folate intake from supplements. Two different measurements of dietary folate intake were used: the baseline consumption and the average consumption from baseline until just before the end of follow-up. The association between folate intake and T2D risk was determined through a modified Poisson regression model with a robust error estimator controlling for potential confounders. For 29 745 person years, 319 cases of diabetes were ascertained. In multivariable analyses, dietary folate intake was inversely associated with risk of T2D for women, not for men. For women, the incidence rate ratio of diabetes in the third tertile compared with the first tertile was 0·57 (95 % CI 0·38-0·87, P for trend=0·0085) in the baseline consumption model and 0·64 (95 % CI 0·43-0·95, P for trend=0·0244) in the average consumption model. These inverse associations was found in both normal fasting blood glucose group and impaired fasting glucose group among women. Among non-users of multinutrients and vitamin supplements, the significant inverse association remained. Thus, higher dietary intake of folate is prospectively associated with lower risk of diabetes for women.

Gene and dietary calcium interaction effects on brachial-ankle pulse wave velocity.

BACKGROUND & AIM: Understanding the lifestyle and genetic factors that affect pulse wave velocity (PWV) may provide clues to preventing atherosclerotic cardiovascular events. The aim of this study is to investigate genome-wide genetic and dietary calcium (Ca) intake interaction effects on brachial-ankle pulse wave velocity (baPWV). METHODS: The baPWV was measured, and Ca intake was quantified by administering a food frequency questionnaire (FFQ) to 3198 participants, which included men and women (≥40 years) from the Korean Multi-Rural communities Cohort study (MRCohort). The interaction effects of dietary Ca intake and 19 single-nucleotide polymorphisms (SNPs) on baPWV were assessed using the general linear models. RESULTS: Dietary Ca intake was not significantly associated with baPWV or any type of SNP among the subjects herein. In men, however, the adducin1 (ADD1) rs4961_C SNP had a significant dietary Ca intake-dependent effect on mean baPWV (pinteraction = 0.002). In women, the interaction of zinc finger proteins 618 (ZNF618) rs10817542_A with dietary Ca intake played a significant and key role in mean baPWV (pinteraction = 0.001). In the results of ADD1 rs4961_C in men and ZNF618 rs10817542_A in women, the minor allele-lowest Ca intake tertile (T1) group had significantly higher mean baPWV value than other subgroups of Ca intake tertile-genotype cross-classification whereas genotype was not a significant effector on mean baPWV values among highest Ca intake subgroups (T3). CONCLUSIONS: The baPWV, a phenotype of arterial stiffness, can be modulated in subjects through regulation of dietary Ca intake, particularly in subjects with more vulnerable genotypes.

Habitual dietary intake of ß-carotene, vitamin C, folate, or vitamin E may interact with single nucleotide polymorphisms on brachial-ankle pulse wave velocity in healthy adults.

PURPOSE: The interaction between genetics and diet may explain the present disagreement in the protective role of vitamin intake on cardiovascular disease. We cross-sectionally assessed the interaction of habitual dietary intake of ß-carotene, vitamin C, folate, and vitamin E with single nucleotide polymorphisms (SNPs) on brachial-ankle pulse wave velocity (baPWV), a measure of arterial stiffness. METHODS: Dietary intakes of ß-carotene, vitamin C, folate, and vitamin E were quantified by a food frequency questionnaire in 3198 healthy men and women (≥ 40 years) from the Korea Multi-Rural communities Cohort study. baPWV was measured, and 19 SNPs were genotyped. The associations and interactions between dietary vitamin intake, SNP genotype, and baPWV were assessed using general linear models. RESULTS: In both men and women, dietary intake of ß-carotene, vitamin C, folate, or vitamin E and baPWV were not directly associated. Vitamin C, folate, and vitamin E intake had an interaction with rs4961 (ADD1) genotype on baPWV in men. rs4961 also interacted with folate intake on baPWV in women. In women, rs10817542 (ZNF618) and rs719856 (CD2AP) had an interaction with ß-carotene and folate intake and rs5443 (GNB3) had an interaction with vitamin E intake on baPWV. In general, minor allele homozygotes with low vitamin intake had higher baPWV than other subgroups. Results were similar when supplement users were excluded. CONCLUSIONS: Higher intake of dietary vitamin C, folate, and vitamin E may be related to high baPWV in healthy Korean men who are minor allele homozygotes of rs4961. In healthy Korean women, dietary folate, ß-carotene, and vitamin E intake may affect baPWV differently according to rs4961, rs10817542, rs719856, or rs5443 genotype. Greater dietary intake of these nutrients may protect those that are genetically vulnerable to stiffening of the arteries.

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.

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 (ß = 0.0006, p = 0.02) and with tea intake and caffeine intake in females (ß = 0.0003, p = 0.04 and ß = 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.

Incidence of and factors for self-reported fragility fractures among middle-aged and elderly women in rural Korea: an 11-year follow-up study.

OBJECTIVES: This community-based cohort study was performed to investigate the incidence of and factors related to self-reported fragility fractures among middle-aged and elderly women living in rural Korea. METHODS: The osteoporosis cohort recruited 430 women 40 to 69 years old in 1999, and 396 of these women were followed over 11 years. In 1999, questionnaires from all participants assessed general characteristics, medical history, lifestyle, menstrual and reproductive characteristics, and bone mineral density. In 2010, self-reported fractures and the date, site, and cause of these fractures were recorded. Cox proportional hazards models were used to calculate hazard ratios (HRs). RESULTS: Seventy-six participants among 3949.7 person-years experienced fragility fractures during the 11-year follow-up. The incidence of fragility fractures was 1924.2 per 100 000 person-years (95% confidence interval [CI], 1491.6 to 2356.8). In the multivariate model, low body mass index (HR, 2.66; 95% CI, 1.13 to 6.24), a parental history of osteoporosis (HR, 2.03; 95% CI, 1.18 to 3.49), and postmenopausal status (HR, 3.50; 95% CI, 1.05 to 11.67) were significantly related to fragility fracture. CONCLUSIONS: Fracture prevention programs are needed among postmenopausal, rural, Korean women with a low body mass index and parental history of osteoporosis Korea.

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.

The effect of vitamin C intake on the risk of hyperuricemia and serum uric acid level in Korean Multi-Rural Communities Cohort.

OBJECTIVE: The aim of this study was to determine the association between vitamin C intake and risk of hyperuricemia or serum uric acid levels in male and female subjects in the Korean Multi-Rural Communities Prospective Cohort. METHODS: This cross-sectional analysis was conducted in 9400 subjects enrolled in the Korean Multi-Rural Communities Cohort Study. The risk of hyperuricemia was assessed in five quintiles (Q1 to Q5) according to dietary and total vitamin C intake using multivariate-adjusted logistic regression models. Relationships between serum uric acid levels and vitamin C intake were evaluated using linear regression analysis after adjustment for covariates. Information about dietary components was collected using validated food frequency questionnaires. RESULTS: Dietary vitamin C intake, but not total vitamin C intake, was significantly different between hyperuricemic and non-hyperuricemic subjects in males (P=0.01) and females (P=0.02). The risk of hyperuricemia decreased with increased dietary vitamin C intake in male and female subjects after multivariate adjustment (P for trend=0.002 in males and P for trend=0.02 in females). An effect of total vitamin C intake on hyperuricemia risk was identified in females (P for trend=0.04), but not males (P for trend=0.06). Serum uric acid level was linearly associated with total vitamin C intake in females (ß=-0.0001, P=0.01), but not with dietary vitamin C intake in either gender. CONCLUSION: This study showed that vitamin C intake might be in part responsible for hyperuricemia or serum uric acid level in the Korean Multi-Rural Communities Cohort.

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.

Self-reported snoring and metabolic syndrome: the Korean Multi-Rural Communities Cohort Study.

PURPOSE: We investigated the association between self-reported snoring and metabolic syndrome (MetS) and its components among a community-dwelling Korean population. METHODS: A total of 7,038 subjects participated in the Korean Multi-Rural Communities Cohort Study between January 2005 and February 2010 and were included in the analysis. Frequency of snoring was classified into never, rarely (<1 day/week), occasionally (1-3 days/week), and habitually (≥4 days/week). RESULTS: In the fully adjusted model, compared to non-snorers, the odds ratio (OR) for MetS of snorers was significantly higher in subjects with rare snoring (OR, 1.42; 95% confidence interval (CI), 1.23-1.64), occasional snoring (OR, 1.79; 95% CI, 1.55-2.07), and habitual snoring (OR, 2.03; 95% CI, 1.77-2.33) than those who did not snore. The ORs for abdominal obesity were significantly higher in rare snoring subjects (OR, 1.51; 95% CI, 1.30-1.75), occasional snoring (OR, 1.71; 95% CI, 1.47-1.98), and habitual snoring (OR, 2.07; 95% CI, 1.80-2.38) than in non-snorers after adjusting for covariates. CONCLUSIONS: Snoring was significantly and linearly associated with MetS, and this association was consistently present in both sexes. Positive and graded associations were observed between snoring frequency and MetS components including high blood pressure, elevated fasting glucose levels, and abdominal obesity, independent of conventional risk factors and other MetS components.

Incremental predictive value of high-sensitivity C-reactive protein for incident hypertension: the Hypertension-Diabetes Daegu Initiative study.

The purpose of this study was to determine the association between serum high-sensitivity C-reactive protein (hs-CRP) and incident hypertension. Study subjects were 452 Koreans who were enrolled in a cohort study. Log-transformed hs-CRP (odds ratio, 1.89; 95% confidence interval, 1.05-3.39; p = 0.035) was an independent predictor of incident hypertension. Inclusion of hs-CRP showed significant increase in the area under the curve from 0.697 to 0.720 (p = 0.042), the net reclassification improvement (0.394, p < 0.001) and integrated discrimination improvement (0.0111, p = 0.045). The hs-CRP added incremental value to the combination of systolic blood pressure and conventional risk factors in predicting incident hypertension.

Higher consumption of sugar-sweetened soft drinks increases the risk of hyperuricemia in Korean population: The Korean Multi-Rural Communities Cohort Study.

OBJECTIVE: The clinical implication of sugar-sweetened soft drinks on the risk of hyperuricemia has increased, especially in Western population studies. The aim of this study is to clarify the association between sugar-sweetened soft drinks and fruit drinks made from oranges and apples and the risk of hyperuricemia in the Korean Multi-Rural Communities Cohort. METHODS: A total of 9400 subjects were enrolled in the Korean Multi-Rural Communities Cohort Study, and a cross-sectional analysis was performed. Five quintiles (Q1-Q5) according to consumption of soft drinks and other fruit/fruit juices were classified and then categorized into three groups (Q1-Q3, Q4, and Q5) to assess the risk of hyperuricemia. Information on dietary intake was collected by well-trained interviewers using validated food frequency questionnaires. RESULTS: Higher consumption of sugar-sweetened soft drinks (Q5) increased the risk of hyperuricemia in males (adjusted OR = 1.35, 95% CI: 1.07-1.71) with a linear trend (p for trend = 0.01) and in females (adjusted OR = 1.40, 95% CI: 1.03-1.90) with no linear trend (p for trend = 0.09), compared to lower consumption (Q1-Q3). However, there were no significant differences of serum uric acid level according to the three categories of soft drink consumption, Q1-Q3, Q3, and Q5, in males (p = 0.21) or in females (p = 0.16), whereas all subjects showed statistical significance of serum uric acid level within the categories (p < 0.001). Estimated amount of soft drink intake was associated with serum uric acid level in males (ß = 0.001; p = 0.01) but not in females (ß = 0.0005; p = 0.10). CONCLUSION: Higher consumption of sugar-sweetened soft drinks increased the risk of hyperuricemia in the Korean population, showing a differential linear trend for hyperuricemia according to gender.

Incidence of metabolic syndrome and relative importance of five components as a predictor of metabolic syndrome: 5-year follow-up study in Korea.

The aim of this study was to describe the incidence of metabolic syndrome and to identify five components as metabolic syndrome predictors. The final study included 1,095 subjects enrolled in a rural part of Daegu Metropolitan City, Korea for a cohort study in 2003. Of these, 762 (69.6%) subjects had participated in the repeat survey. During the five-year follow-up, incidence density was significantly higher for women than for men (men, 30.0/1,000 person-years; women, 46.4/1,000 person-years). In both men and women, incidence of metabolic syndrome showed a significant increase with increasing number of metabolic syndrome components at baseline. Compared with individuals presenting none of components at baseline, relative risks were increased 1.22 (men; 95% CI, 0.43-3.51), 2.21 (women; 95% CI, 0.98-4.97) times more for individuals with one component of metabolic syndrome and 5.30 (men; 95% CI, 2.31-12.13), 5.53 (women; 95% CI, 2.78-11.01) times more for those who had two components. In multivariate analysis, the most powerful risk factor for metabolic syndrome was abdominal obesity in men and low HDL-cholesterol in women (adjusted relative risk, 3.28, 2.53, respectively). Consequently, finding a high risk group for metabolic syndrome according to gender and prevention of metabolic syndrome through lifestyle modification are essential.

Lower zinc bioavailability may be related to higher risk of subclinical atherosclerosis in Korean adults.

BACKGROUND: There is a proposed link between dietary zinc intake and atherosclerosis, but this relationship remains unclear. Phytate may contribute to this relationship by influencing zinc bioavailability. OBJECTIVE: The aim of this study is to examine the relationship between zinc bioavailability and subclinical atherosclerosis in healthy Korean adults. MATERIALS AND METHODS: The present cross-sectional analysis used baseline data from the Korean multi-Rural Communities Cohort Study (MRCohort), which is a part of The Korean Genome Epidemiology Study (KoGES). A total of 5,532 subjects (2,116 men and 3,416 women) aged 40 years and older were recruited from rural communities in South Korea between 2005 and 2010. Phytate:zinc molar ratio, estimated from a food-based food frequency questionnaire (FFQ) of 106 food items, was used to determine zinc bioavailability, and carotid intima media thickness (cIMT) and pulse wave velocity (PWV) were measured to calculate the subclinical atherosclerotic index. RESULTS: We found that phytate:zinc molar ratio is positively related to cIMT in men. A higher phytate:zinc molar ratio was significantly related to an increased risk of atherosclerosis in men, defined as the 80(th) percentile value of cIMT (5(th) vs. 1(st) quintile, OR = 2.11, 95% CI 1.42-3.15, P for trend = 0.0009), and especially in elderly men (5(th) vs. 1(st) quintile, OR = 2.58, 95% CI 1.52-4.37, P for trend = 0.0021). We found a positive relationship between phytate:zinc molar ratio and atherosclerosis risk among women aged 65 years or younger. Phytate:zinc molar ratio was not found to be related to PWV. CONCLUSIONS: Lower zinc bioavailability may be related to higher atherosclerosis risk.

The impact of serum uric acid level on arterial stiffness and carotid atherosclerosis: the Korean Multi-Rural Communities Cohort study.

OBJECTIVE: Serum uric acid level has been found to be associated with a risk factor for cardiovascular diseases. However, the topic has not been explored in the general population, especially in Korea. This study was designed to determine whether serum uric acid is associated with carotid atherosclerosis and arterial stiffness in the Korean Multi-Rural Communities Cohort study. METHODS: A total of 5568 participants from the Korean Multi-Rural Communities Cohort were evaluated for the risk of hyperuricemia in cardiovascular atherosclerosis. Important surrogates for cardiovascular atherosclerosis such as intima-media thickness (IMT) and brachial-ankle pulse wave velocity (baPWV) were assessed. We evaluated the association between these atherosclerosis indices and serum uric acid level or hyperuricemia through multivariate-adjusted logistic and linear regression analyses. RESULTS: There was a significant difference of carotid IMT and baPWV between males and females (p < 0.0001, respectively). Both male and female subjects with hyperuricemia showed higher baPWV than subjects without hyperuricemia (p = 0.0004 for males; p = 0.001 for females). Serum uric acid level was positively correlated with baPWV in males (ß = 0.0006, p < 0.0001) and in females (ß = 0.0001, p = 0.04), whereas no association between serum uric acid and carotid IMT was found in either gender. A linear relationship of baPWV with increasing serum uric acid level was observed in males (p = 0.0005) and in females (p = 0.004). CONCLUSION: Serum uric acid level could be considered an important risk factor for arterial stiffness in Korean population, whereas carotid IMT is not associated with serum uric acid in either gender when using data from the Korean Multi-Rural Communities Cohort study.

Incidence of hypertension in Korea: 5-year follow-up study.

Limited data are available about the incidence of hypertension over the 5-yr in non-hypertensive subjects. The study subjects were 1,806 subjects enrolled in a rural area of Daegu, Korea for a cohort study from August to November 2003. Of them, 1,287 (71.3%) individuals had another examination 5 yr later. To estimate the incidence of hypertension, 730 non-hypertensive individuals (265 males; mean age = 56.6 ± 11.1 yr-old) at baseline examination were analyzed in this study. Hypertension was defined as either a new diagnosis of hypertension or self-reports of newly initiated antihypertensive treatment; prehypertension was if the systolic blood pressure was 120-139 mmHg and/or diastolic blood pressure was 80-89 mmHg. During the 5-yr follow-up, 195 (26.7%) non-hypertensive individuals developed incident hypertension. The age-adjusted 5-yr incidence rates of hypertension were 22.9% (95% confidence interval [CI] = 19.9-29.0) in overall subjects, 22.2% (95% CI = 17.2-27.2) in men, and 24.3% (95% CI = 20.4-28.2) in women. The incidence rates of hypertension significantly increased with age. In the multivariate analysis, prehypertension (Odds ratio [OR] 2.25; P < 0.001) and older age (OR 2.26; P = 0.010) were independent predictors for incident hypertension. In this rapidly aging society, population-based preventive approach to decrease blood pressure, particularly in subjects with prehypertension, is needed to reduce hypertension.

Prevalence of Diabetes Mellitus and Prediabetes in Dalseong-gun, Daegu City, Korea.

BACKGROUND: The aim of the present study was to determine the population-based prevalence of diabetes mellitus (DM) and prediabetes in a rural district of Daegu City, Korea. METHODS: Between August and November 2003, a community-based health survey of adults aged 20 years and older was performed in the rural district of Dalseong-gun in Daegu City. A total of 1,806 of all eligible individuals agreed to participate. Fasting plasma glucose was measured in all participants. Two hour oral glucose tolerance was measured in the 1,773 participants for whom there was neither an established diagnosis of DM nor evidence of DM according to fasting glucose levels. The prevalence of DM and prediabetes was determined according to the 2003 criteria of the American Diabetes Association. Subjects with prediabetes were classified into one of three categories of glucose intolerance: isolated impaired fasting glucose (IFG); isolated impaired glucose tolerance (IGT); or combined IFG and IGT. RESULTS: The prevalence of DM was 12.2%. The highest prevalence rates were observed in subjects in their seventies. A total of 34.7% of all subjects who were assigned a diagnosis of DM in the present study had not been diagnosed previously. The prevalence of prediabetes was 22.7%. The highest prevalence rates were observed in subjects in their fifties. CONCLUSION: The present study identified prevalence rates of 12.2% for DM (age-standardized prevalence rate [ASR], 6.8%), and 22.7% for prediabetes (ASR 18.5%). These results emphasize the need for community health promotion strategies to prevent or delay the onset of DM in individuals with prediabetes.

Dietary zinc intake is inversely related to subclinical atherosclerosis measured by carotid intima-media thickness.

The relationship between dietary Zn intake and the risk of atherosclerosis remains unclear, and no epidemiological studies have been reported on the effects of dietary Zn intake on morphological changes in the vascular wall. We examined the relationship between dietary Zn intake and common carotid intima-media thickness (IMT) as a marker of subclinical atherosclerosis among the middle-aged and elderly populations. A cross-sectional analysis of a prospective cohort baseline study was performed with 4564 adults aged 40-89 years and free of clinical CVD. Dietary data were collected by trained interviewers using an FFQ. Common carotid IMT was measured using a B-mode ultrasound imaging technique. Subclinical atherosclerosis was determined using carotid IMT, and defined as > 80th percentile of carotid IMT or ≥ 1 mm of carotid IMT. After adjustment for potential confounders, the mean carotid IMT in the low Zn intake group was higher than that in the high Zn intake group. When subclinical atherosclerosis was defined as > 80th percentile value of IMT or ≥ 1 mm of carotid IMT, after adjustment for potential confounders, Zn intake was inversely related to subclinical atherosclerosis (5th v. 1st quintile, OR 0.64, 95% CI 0.45, 0.90, P for trend = 0.069; 5th v. 1st quintile, OR 0.34, 95% CI 0.16, 0.70, P for trend = 0.005, respectively). In persons free of clinical CVD, dietary Zn intake was inversely correlated with subclinical atherosclerosis. The present findings suggest a putative protective role of dietary Zn intake against the development of atherosclerosis.

[Association between gamma-glutamyltransferase and hypertension incidence in rural prehypertensive adults].

OBJECTIVES: Prehypertension is associated with a higher risk of developing hypertension compared with normotension. Yet, factors predicting the development of hypertension among prehypertensive people are ill-understood. This prospective cohort study was performed to examine if serum gamma-glutamyltrasferase (GGT) within a normal range can predict the future risk of hypertension among prehypertensive adults. METHODS: Study subjects were 293 prehypertensive persons >30-years-of-age who participated in a community-based health survey in 2003 and who were followed up in 2008. Sex-specific quartiles of baseline serum GGT were used to examine association with 5-year hypertension incidence. RESULTS: Baseline serum GGT within normal range predicted the risk of developing hypertension for 5 years only in prehypertensive women. Adjusted relative risks were 1.0, 3.7, 3.6, and 6.0 according to quartiles of baseline serum GGT (P for trend <0.01). This pattern was similarly observed in non-drinkers. However, serum GGT was not associated with incident hypertension in men. Different from serum GGT, baseline serum alanine aminotransferase, another well-known liver enzyme, did not predict the risk of incident hypertension in both genders. CONCLUSIONS: Even though baseline serum GGT within normal range strongly predicted the future risk of hypertension, it was observed only in women, Although underlying mechanisms of this association are currently unclear, serum GGT can be used to select a high risk group of hypertension in prehypertensive women.