Tomo Kusunoki

Uric acid is an independent risk factor for carotid atherosclerosis in a Japanese elderly population without metabolic syndrome

BackgroundCarotid intima-media thickness (IMT) is an useful surrogate marker of cardiovascular disease. Associations between uric acid (UA), metabolic syndrome (MetS) and carotid IMT have been reported, but findings regarding the relationship have been inconsistent.MethodsA total of 1,579 Japanese elderly subjects aged ≥65 years {663 men aged, 78 ± 8 (mean ± standard deviation) years and 916 women aged 79 ± 8 years} were divided into 4 groups according to UA quartiles. We first investigated the association between UA concentrations and confounding factors including MetS; then, we assessed whether there is an independent association of UA with carotid IMT and atherosclerosis in participants subdivided according to gender and MetS status.ResultsCarotid IMT was significantly increased according to the quartiles of UA in both genders without MetS and women with MetS. Multivariate logistic regression analysis showed that odds ratio (OR) {95% confidence interval (CI)} in men for carotid atherosclerosis was significantly increased in the third (OR, 1.75; 95% CI, 1.02-3.02), and fourth quartiles (OR, 2.01; 95% CI, 1.12-3.60) of UA compared with that in the first quartile of UA, and the OR in women was significantly increased in the fourth quartile (OR, 2.10; 95% CI, 1.30-3.39). Similarly, the ORs were significantly associated with increasing quartiles of UA in both genders without MetS, but not necessarily increased in those with MetS.ConclusionsUA was found to be an independent risk factor for incidence of carotid atherosclerosis in both genders without MetS.

An Association between Body Mass Index and Estimated Glomerular Filtration Rate

Chronic kidney disease (CKD) is a major public health problem. However, few studies have examined the significance of body mass index (BMI) as a risk factor for the development of CKD in the general Japanese population. Study participants without a clinical history of stroke, transient ischemic attack, myocardial infarction, angina or renal failure (754 men aged 56±15 [mean±SD] years and 962 women aged 59±13 years) were randomly recruited from a single community at the time of their annual health examination. We examined the relationship between increased weight (i.e., BMI) and renal function evaluated by the estimated glomerular filtration rate (eGFR) using the Modification of Diet in Renal Disease Study Group equation. Increased BMI was consistently associated with reduced eGFR. Estimated GFR was lower in participants with upper normal body weight (BMI, 22.0 to 24.9 kg/m2) or who were overweight or obese (BMI≥25 kg/m2), compared with participants with lower normal body weight (BMI, 18.5 to 21.9 kg/m2). Stepwise multiple regression analysis using eGFR as an objective variable, adjusted for various risk factors as explanatory variables, showed that BMI (β = –0.075) was significantly and independently associated with eGFR, in addition to age, log triglycerides, low-density lipoprotein cholesterol and log fasting blood glucose. Compared with those with lower normal body weight, multivariate-adjusted odds ratios for moderately reduced renal function, defined as an eGFR < 60 mL/min/1.73 m2 , were 1.86 (1.01–3.42) for upper normal weight and 2.02 (1.01–4.03) for overweight or obese individuals. In conclusion, increased BMI is strongly associated with decreased eGFR in community-dwelling healthy persons.

High-sensitivity c-reactive protein and gamma-glutamyl transferase levels are synergistically associated with metabolic syndrome in community-dwelling persons

BackgroundMetabolic syndrome (MetS) is associated with an increased risk of major cardiovascular events. Increased high-sensitivity C-reactive protein (hsCRP) levels are associated with MetS and its components. Changes in gamma-glutamyl transferase (GGT) levels in response to oxidative stress are also associated with MetS, and the levels could be modulated by hsCRP.MethodsFrom a single community, we recruited 822 men (mean age, 61 ± 14 years) and 1,097 women (63 ± 12 years) during their annual health examination. We investigated whether increased hsCRP and GGT levels are synergistically associated with MetS and insulin resistance evaluated by Homeostasis of model assessment of insulin resistance (HOMA-IR).ResultsOf these subjects, 141 men (17.2%) and 170 women (15.5%) had MetS. Participants with MetS had a higher hsCRP and GGT level than those without MetS in both genders, and the HOMA-IR increased significantly in correlation with an increase in hsCRP and GGT. In men, the adjusted odds ratios (95% confidence interval) for MetS across tertiles of hsCRP and GGT were 1.00, 1.69 (1.01-2.80), and 2.13 (1.29-3.52), and 1.00, 3.26 (1.84-5.78) and 6.11 (3.30-11.3), respectively. In women, the respective corresponding values were 1.00, 1.54 (0.92-2.60), and 3.08 (1.88-5.06), and 1.00, 1.70 (1.04-2.79) and 2.67 (1.66-4.30). The interaction between increased hsCRP and GGT was a significant and independent determinant for MetS and insulin resistance in both genders.ConclusionsThese results suggested that higher CRP and GGT levels were synergistically associated with MetS and insulin resistance, independently of other confounding factor in the general population.

Relationships between lipid profiles and metabolic syndrome, insulin resistance and serum high molecular adiponectin in Japanese community-dwelling adults.

BackgroundThere are few studies to demonstrate the associations between newly addressed lipid profiles and metabolic syndrome (MetS)-associated variables.MethodsStudy participants without medications for hypertension, diabetes, or dyslipidemia {614 men aged 58 ± 14 (mean ± standard deviation; range, 20-89) years and 779 women aged 60 ± 12 (range, 21-88) years} were randomly recruited from a single community at the time of their annual health examination. The association between lipid profiles (total cholesterol (T-C), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), non-HDL-C, T-C/HDL-C, TG/HDL-C, LDL-C/HDL-C ratio and MetS, Insulin resistance by homeostasis model assessment of insulin resistance (HOMA-IR), and serum HMW adiponectin were analyzed.ResultsIn multiple linear regression analysis, TG/HDL-C and T-C/HDL-C ratios as well as TG showed significantly strong associations with all three MetS-associated variables in both men and women. In men, the ROC curve analyses showed that the best marker for these variables was TG/HDL-C ratio, with the AUC for presence of MetS (AUC, 0.82; 95% CI, 0.77-0.87), HOMA-IR (AUC, 0.75; 95% CI, 0.70-0.80), and serum HMW adiponectin (AUC, 0.67; 95% CI, 0.63-0.71), respectively. The T-C/HDL-C ratio, TG, HDL-C, LDL-C/HDL-C ratio, and non-HDL-C also discriminated these markers; however all their AUC estimates were lower than TG/HDL-C ratio. These results were similar in women.ConclusionIn Japanese community-dwelling adults, lipid ratios of TG/HDL-C, T-C/HDL-C, LDL-C/HDL-C as well as TG and HDL-C were consistently associated with MetS, insulin resistance and serum HMW adiponectin. Lipid ratios may be used as reliable markers.

Serum Uric Acid Is More Strongly Associated with Impaired Fasting Glucose in Women than in Men from a Community-Dwelling Population

Serum uric acid (SUA) levels are associated with metabolic syndrome (MetS) and its components such as glucose intolerance and type 2 diabetes. It is unknown whether there are gender-specific differences regarding the relationship between SUA levels, impaired fasting glucose (IFG) and newly detected diabetes. We recruited 1,209 men aged 60±15 (range, 19–89) years and 1,636 women aged 63±12 (range, 19–89) years during their annual health examination from a single community. We investigated the association between SUA levels and six categories according to fasting plasma glucose (FPG) level {normal fasting glucose (NFG), <100 mg/dL; high NFG-WHO, 100 to 109 mg/dL; IFG-WHO, 110 to 125 mg/dL; IFG-ADA, 100 to 125 mg/dL; newly detected diabetes, ≥126 mg/dL; known diabetes} SUA levels were more strongly associated with the different FPG categories in women compared with men. In women, the associations remained significant for IFG-WHO (OR, 1.23, 95% CI, 1.00–1.50) and newly detected diabetes (OR, 1.33, 95% CI, 1.03–1.72) following multivariate adjustment. However, in men all the associations were not significant. Thus, there was a significant interaction between gender and SUA level for newly detected diabetes (P = 0.005). SUA levels are associated with different categories of impaired fasting glucose in participants from community-dwelling persons, particularly in women.

Alanine aminotransferase/aspartate aminotransferase ratio is the best surrogate marker for insulin resistance in non-obese Japanese adults

BackgroundThe aim of the present study was to examine how liver markers are associated with insulin resistance in Japanese community-dwelling adults.MethodsThis cross-sectional study included 587 men aged 58 ± 14 (mean ± standard deviation; range, 20–89) years and 755 women aged 60 ± 12 (range, 21–88) years. The study sample consisted of 998 (74.4%) non-obese [body mass index (BMI) <25.0 kg/m2] and 344 (25.6%) overweight (BMI ≥25 kg/m2) subjects. Insulin resistance was defined by homeostasis model assessment of insulin resistance (HOMA-IR) of at least 2.5, and HOMA-IR and potential confounders were compared between the groups. Areas under the curve (AUC) of the receiver operating characteristic curves (ROC) were used to compare the power of these serum markers.ResultsIn non-obese subjects, the best marker of insulin resistance was alanine aminotransferase (ALT)/aspartate aminotransferase (AST) ratio of 0.70 (95% confidence interval (CI), 0.63-0.77). In overweight subjects, AUC values for the ALT/AST ratio and ALT were 0.66 (0.59-0.72) and 0.66 (0.59-0.72), respectively. Multiple linear regression analyses for HOMA-IR showed that ALT/AST ratios were independently and significantly associated with HOMA-IR as well as other confounding factors in both non-obese and overweight subjects. The optimal cut-off point to identifying insulin resistance for these markers yielded the following values: ALT/AST ratio of ≥0.82 in non-obese subjects and ≥1.02 in overweight subjects. In non-obese subjects, the positive likelihood ratio was greatest for ALT/AST ratio.ConclusionsIn non-obese Japanese adults, ALT/AST ratio may be the best reliable marker of insulin resistance.

A Slightly Low Hemoglobin Level Is Beneficially Associated with Arterial Stiffness in Japanese Community-Dwelling Women

Pulse wave velocity (PWV) is a simple and noninvasive method of measuring arterial stiffness for the assessment of cardiovascular disease in high-risk populations. This association may be further confounded by hemoglobin status, which is involved in the development of atherosclerosis. We randomly recruited 120 men and 223 women aged 69 ± 9 and 68 ± 7 years, respectively, during their annual health examination in a single community. Arterial stiffness was evaluated by brachial–ankle PWV (baPWV). The value of baPWV was different from men and women. In men, baPWV was not related to hemoglobin levels (r = 0.013, P = .886), but in women baPWV increased significantly and progressively with increased hemoglobin levels (r = 0.276, P < .001). Stepwise multiple regression analysis using the baPWV as objective variables, adjusted for confounding factors as explanatory variables, showed that only in women, hemoglobin levels (β = 0.165, P = .001) as well as age (β = 0.268, P < .001), body mass index (BMI; β = −0.165, P < .001), systolic blood pressure (SBP; β = 0.429, P < .001), prevalence of antihypertensive (β = 0.154, P = .002), heart rate (HR; β = 0.108, P = .017), and antilipidemic medication (β = 0.094, P = .036), and estimated glomerular filtration rate (eGFR; β = −0.147, P = .003) were significantly and independently associated with baPWV. Multivariate-adjusted baPWV was significantly higher in hemoglobin groups of ≥12.7 g/dL (Group-2, Group-4) than in the lowest hemoglobin group (10.0–12.6 g/dL; P = .032). A slightly low hemoglobin level was beneficially associated with arterial stiffness in community-dwelling women but not men.

Effect of weight loss on central systolic blood pressure in elderly community-dwelling persons.

Central blood pressure (BP) has been shown to strongly associate with cardiovascular disease and outcome. Recent studies have demonstrated a relationship between changes in body size by exercise training and peripheral BP; however, the effect on changes in central BP is unknown. The aim of this study was to assess whether changes in body size are independently related to changes in central BP in the elderly. The subjects were 11 men (mean age, 68±6 years) and 84 women (68±7 years) from a rural village. Before and at the end of the 12-week training program, metabolic variables, and first peak radial systolic BP (SBP1) and second peak radial SBP (SBP2) as estimates of central SBP, were obtained. Radial augmentation index (AI) was calculated as follows: ((SBP2−diastolic BP (DBP))/(SBP1−DBP)) × 100 (%) and we used AI corrected at heart rate 75 per min (AI@75). After the 12-week training program, weight loss correlated strongly with reduction in brachial mean arterial pressure (MAP), radial SBP1, SBP2 and AI@75. After adjusting for confounding factors, weight loss was significantly and independently associated with each reduction in brachial MAP (β=0.34, P=0.001), radial SBP1 (β=0.31, P=0.002), SBP2 (β=0.37, P<0.001) and AI@75 (β=0.36, P=0.001). These findings suggest that weight loss by a 12-week training program may be an effective strategy to improve central BP parameters among Japanese elderly persons.

Association between fasting plasma glucose and high-sensitivity C-reactive protein: gender differences in a Japanese community-dwelling population.

BackgroundHigh sensitivity C-reactive protein (hsCRP) is an acute phase reactant and a sensitive marker of inflammation. Hyperglycemia can potentially promote the production of CRP. The aim of this study was to determine whether increased fasting plasma glucose (FPG) levels are associated with elevated hsCRP concentrations by gender.MethodsWe recruited 822 men (mean age, 61 ± 14 years) and 1,097 women (63 ± 12 years) during their annual health examination from a single community. We cross-sectionally examined whether FPG levels are associated with hsCRP concentrations, and whether this association is independent of gender, body mass index (BMI) and other components of the metabolic syndrome.ResultsIn women only, hsCRP increased significantly and progressively with increasing FPG (r = 0.169, P < 0.001). The stepwise multiple linear regression analysis using hsCRP as an objective variable, adjusted for confounding factors as explanatory variables, showed that FPG as well as age, BMI, systolic blood pressure, high-density lipoprotein cholesterol (HDL-C), uric acid, and high molecular weight adiponectin were significantly associated with hsCRP in women, but not in men. There was significant gender interaction, and an increase in hsCRP levels that was greater in women with BMI ≥ 25 kg/m2 and higher FPG than in men.ConclusionsThese results suggested that hsCRP levels increase continuously across the FPG spectrum starting from the lowest FPG in both men and women. However, increase in hsCRP levels was greater in women than men.

Low-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio is the best surrogate marker for insulin resistance in non-obese Japanese adults.

BackgroundThe aim of the present study was to examine how lipid profiles are associated with insulin resistance in Japanese community-dwelling adults.MethodsThis cross-sectional study included 614 men aged 58 ± 14 (mean ± standard deviation; range, 20-89) years and 779 women aged 60 ± 12 (range, 21-88) years. The study sample were 1,042 (74.8%) non-obese (BMI < 25.0 kg/m2) and 351 (25.2%) overweight (BMI ≥ 25 kg/m2) subjects. Insulin resistance was defined by homeostasis model assessment of insulin resistance (HOMA-IR) of at least 2.5. The areas under the curve (AUC) of the receiver operating characteristic curves (ROC) were used to compare the power of these serum markers.ResultsIn non-obese subjects, the best marker of insulin resistance was low-density lipoprotein cholesterol (LDL-C)/high-density lipoprotein cholesterol (HDL-C) ratio of 0.74 (95% confidence interval (CI), 0.66-0.80). The HDL-C, triglyceride (TG)/HDL-C ratio, and non-HDL-C also discriminated insulin resistance, as the values for AUC were 0.31 (95% CI, 0.24-0.38), 0.69 (95% CI, 0.62-0.75) and 0.69 (95% CI, 0.62-0.75), respectively. In overweight subjects, the AUC for TG and TG/HDL-C ratio were 0.64 (0.58-0.71) and 0.64 (0.57-0.70), respectively. The optimal cut-off point to identifying insulin resistance for these markers yielded the following values: TG/HDL-C ratio of ≥1.50 and LDL-C/HDL-C ratio of ≥2.14 in non-obese subjects, and ≥2.20, ≥2.25 in overweight subjects. In non-obese subjects, the positive likelihood ratio was greatest for LDL-C/HDL-C ratio.ConclusionIn non-obese Japanese adults, LDL-C/HDL-C ratio may be the best reliable marker of insulin resistance.