Ventral Variant Posterior Cortical Atrophy with Occipito-temporal Accumulation of Tau Proteins/Astrocyte Gliosis

A 73-year-old woman with posterior cortical atrophy (PCA) presented with progressive apperceptive visual agnosia, alexia, agraphia, ventral simultanagnosia, prosopagnosia, and allocentric (stimulus-centered) left-sided hemispatial neglect. All of these symptoms were attributed to damage to the bilateral occipito-temporal cortices, consistent with ventral variant PCA. While the Pittsburgh compound B uptake was extensively distributed throughout the occipito-parietal (dorsal) and occipito-temporal (ventral) areas, the THK5351 (ligand binding to tau aggregates/astrocyte gliosis) accumulation was limited to the ventral area. These findings suggest that local accumulation of tau proteins and/or astrocyte gliosis over the occipito-temporal cortices can result in ventral variant PCA.

Characteristic changes in plasma glutamate levels and free amino acid profiles in Japanese patients with type 1 diabetes mellitus

AIMS/INTRODUCTION

In addition to absolute insulin deficiency, dysregulated glucagon in type 1 diabetes is considered pathophysiologically important. Previously, we confirmed the presence of dysregulated glucagon in Japanese patients with type 1 diabetes, and found a significant correlation between plasma glucagon and blood urea nitrogen levels, suggesting an association between glucagon and amino acid metabolism. In this study, we evaluated plasma amino acid levels in Japanese patients with type 1 diabetes in the context of their functional relationship with glucagon.

MATERIALS AND METHODS

We assessed plasma free amino acid levels using liquid chromatography-mass spectrometry in 77 Japanese patients with type 1 diabetes, and statistically analyzed their characteristics and relationships with clinical parameters, including glucagon.

RESULTS

Participants with type 1 diabetes showed a large decrease in glutamate levels together with a characteristic change in plasma free amino acid profiles. The network structural prediction analyses showed correlations between each amino acid and glucagon in type 1 diabetes.

CONCLUSIONS

Participants with type 1 diabetes showed characteristic changes in plasma glutamate levels and free amino acid profiles compared with controls and type 2 diabetes patients. Glucagon showed a closer correlation with amino acids than with parameters of glucose metabolism, suggesting that type 1 diabetes includes dysregulation in amino acids through dysregulated glucagon from remaining pancreatic α-cells, together with that in glucose by insulin deficiency.

Does Glycated Albumin Increase with Body Weight Reduction in Obese Non-Diabetic Subjects?

We reported that the body mass index (BMI) may exert a negative effect on glycated albumin (GA) in non-diabetic subjects and patients with type 2 diabetes mellitus. In addition, we suggested a mechanism in which chronic inflammation in obesity may enhance albumin catabolism, leading to a decrease in GA levels for non-diabetic subjects. In the present study, we examined whether GA levels increased with body weight reduction in obese, non-diabetic subjects. Among the subjects who underwent complete medical checkups in 2010 and in 2015, 101 subjects with BMIs of 25 kg/m² or higher, without diabetes mellitus in 2010 were included in this study. Correlations of changes in BMI for five years (ΔBMI) with changes in various clinical laboratory test values [ΔC-reactive protein (CRP), ΔGA, ΔHbA1c, Δfasting plasma glucose (FPG), ΔGA/HbA1c and ΔGA/FPG] were investigated. ΔBMI significantly and positively correlated with ΔCRP, while ΔBMI did not significantly correlate with ΔGA. ΔBMI significantly and positively correlated with ΔHbA1c and ΔFPG. Furthermore, ΔBMI showed significant negative correlations with ΔGA/HbA1c and ΔGA/FPG. GA levels did not increase with body weight reduction in obese non-diabetic subjects. Such a phenomenon might be considered the result when the positive control of GA levels through decreases in chronic inflammation due to body weight reduction was counterbalanced by the negative control of GA levels through improvement in glucose tolerance.

Plasma amino acid profile associated with fatty liver disease and co-occurrence of metabolic risk factors

Fatty liver disease (FLD) increases the risk of diabetes, cardiovascular disease, and steatohepatitis, which leads to fibrosis, cirrhosis, and hepatocellular carcinoma. Thus, the early detection of FLD is necessary. We aimed to find a quantitative and feasible model for discriminating the FLD, based on plasma free amino acid (PFAA) profiles. We constructed models of the relationship between PFAA levels in 2,000 generally healthy Japanese subjects and the diagnosis of FLD by abdominal ultrasound scan by multiple logistic regression analysis with variable selection. The performance of these models for FLD discrimination was validated using an independent data set of 2,160 subjects. The generated PFAA-based model was able to identify FLD patients. The area under the receiver operating characteristic curve for the model was 0.83, which was higher than those of other existing liver function-associated markers ranging from 0.53 to 0.80. The value of the linear discriminant in the model yielded the adjusted odds ratio (with 95% confidence intervals) for a 1 standard deviation increase of 2.63 (2.14–3.25) in the multiple logistic regression analysis with known liver function-associated covariates. Interestingly, the linear discriminant values were significantly associated with the progression of FLD, and patients with nonalcoholic steatohepatitis also exhibited higher values.

Lower risk of progression from prediabetes to diabetes with health checkup with lifestyle education: Japan Ningen Dock study

BACKGROUND AND AIMS

To investigate whether the progression from prediabetes to diabetes is lower among those who undertake Ningen Dock (comprehensive health checkups with lifestyle education and doctor's consultation) than those who undertake basic mandatory occupational health checkups.

METHODS AND RESULTS

Subjects aged 30-69 years with complete annual data from 2008 to 2012 for either Ningen Dock or basic health checkups were enrolled. Subjects with prediabetes (fasting plasma glucose 100-125 mg/dl or HbA1c 5.7-6.4%) at baseline were selected (14,928 in the comprehensive group and 10,433 in the basic group). The incidence of diabetes (fasting plasma glucose ≥ 126 mg/dl, HbA1c ≥ 6.5% or taking glucose-lowering drugs) and the reduction of risk factors were compared. After 4 years, 3226 cases of diabetes occurred among 25,361 subjects with prediabetes. The incidence of diabetes was lower in the comprehensive group than the basic group (2.9 vs. 3.8 cases/100 person-years, hazard ratio 0.75, 95% confidence interval 0.68-0.81 after adjustment). Moreover, more overweight subjects controlled their body mass index (16.2% vs. 13.2%) and more began a daily exercise habit (11.8% vs. 8.5%) in the comprehensive group than in the basic group. The incidence of diabetes was lower in subjects who could control their weight or start daily exercise at year 1 in the comprehensive group.

CONCLUSION

Progression from prediabetes to diabetes was significantly lower in subjects undertaking a comprehensive health checkup with lifestyle education. Lifestyle education at health checkup for people with prediabetes might prevent progression to diabetes by reducing modifiable risk factors.

Plasma Free Amino Acid Profiles Predict Four-Year Risk of Developing Diabetes, Metabolic Syndrome, Dyslipidemia, and Hypertension in Japanese Population

Plasma free amino acid (PFAA) profile is highlighted in its association with visceral obesity and hyperinsulinemia, and future diabetes. Indeed PFAA profiling potentially can evaluate individuals' future risks of developing lifestyle-related diseases, in addition to diabetes. However, few studies have been performed especially in Asian populations, about the optimal combination of PFAAs for evaluating health risks. We quantified PFAA levels in 3,701 Japanese subjects, and determined visceral fat area (VFA) and two-hour post-challenge insulin (Ins120 min) values in 865 and 1,160 subjects, respectively. Then, models between PFAA levels and the VFA or Ins120 min values were constructed by multiple linear regression analysis with variable selection. Finally, a cohort study of 2,984 subjects to examine capabilities of the obtained models for predicting four-year risk of developing new-onset lifestyle-related diseases was conducted. The correlation coefficients of the obtained PFAA models against VFA or Ins120 min were higher than single PFAA level. Our models work well for future risk prediction. Even after adjusting for commonly accepted multiple risk factors, these models can predict future development of diabetes, metabolic syndrome, and dyslipidemia. PFAA profiles confer independent and differing contributions to increasing the lifestyle-related disease risks in addition to the currently known factors in a general Japanese population.

Atherosclerosis as a possible extrahepatic manifestation of chronic hepatitis C virus infection

Chronic infection and associated inflammation may play a role in various unfavorable pathologic conditions, including atherosclerosis. Chronic hepatitis C virus (HCV) infection is thought to be associated with a higher prevalence of atherosclerotic vascular changes in the coronary artery, cerebrovascular artery, and carotid artery; however, little is known about the precise mechanisms by which HCV enhances atherogenic processes. Furthermore, some studies have found no association, or even an inverse association, between HCV infection and atherosclerotic vascular changes or cardiovascular events. Differences in data regarding the mode of association may be because of variations in sample size, target population, and study design. Nevertheless, physicians should be aware of cardiovascular disorders as a possible comorbidity – owing to their considerable consequences – among patients with chronic HCV infection.

Current dietary salt intake of Japanese individuals assessed during health check-up

Excess salt intake is a risk factor for increased blood pressure (BP) and hypertension. To prevent hypertension, the reduction of salt intake is promoted in many countries. For people with hypertension or cardiovascular disease (CVD), a more severe restriction of salt intake is indispensable. Japanese individuals consume high quantities of salt, and it is thus important to determine the degree to which the salt intake of these individuals has been restricted. Here, we investigated the current level of salt consumption of Japanese individuals using data obtained during annual health check-ups. A total of 10 762 individuals were assessed who underwent annual health check-ups at our institution in 2011. The estimated daily salt intake (EDSI) was calculated using spot urine samples. The average EDSI was 7.83±2.02 g per day. BP increased in proportion to the EDSI, and multivariate logistic regression analysis showed that the EDSI was a significant and independent risk factor for hypertension. The average EDSI of the subjects with hypertension or a history of CVD was higher than that of the subjects without these diseases. The subjects who drank more heavily showed higher EDSIs. This study demonstrated that the average EDSI of the subjects needing to restrict their salt intake because of past or present illnesses was high. To achieve adherence to the recommended reduction of salt intake, more efforts are required.

Relationship between serum uric acid and serum oxidative stress markers in the Japanese general population

BACKGROUND

Increased production of reactive oxygen species is a condition that is associated with, and plays a role in the progression of, various disorders such as hypertension, atherosclerosis, and diabetes.

PURPOSE

To assess in vivo oxidative stress levels and antioxidant potential and to analyze the relationship with serum uric acid (UA) levels.

METHODS AND RESULTS

Oxidative stress levels (derivatives of reactive oxygen metabolites, d-ROMs) and antioxidant potential (biological antioxidant potential, BAP) were measured in individuals who underwent a general health screening test, and data were analyzed from 8,025 individuals (2,953 women and 5,072 men) who were free from UA-lowering medication. Higher serum UA levels were associated with increased levels of d-ROMs in both genders, and this trend was more prominent in women. In addition, higher UA levels were also associated with higher BAP in both genders, although the dose dependence was not apparent in men. These associations remained statistically significant after adjusting for age, blood pressure, renal function, albuminuria, C-reactive protein, and insulin resistance index.

CONCLUSIONS

In individuals who underwent general health screening, serum UA levels were positively associated with both d-ROMs and BAP levels. Whether lowering of UA by lifestyle modification or by medication alters d-ROM/BAP levels awaits further investigations. .

Hyperuricemia is a significant risk factor for the onset of chronic kidney disease

BACKGROUND

Recent studies have shown that hyperuricemia is an independent risk factor for cardiovascular disease. However, few studies have examined whether hyperuricemia is a risk factor for chronic kidney disease (CKD), so to investigate the significance of hyperuricemia as a risk factor for CKD, we analyzed data collected in annual health check-ups.

METHODS

The data of 11,048 subjects who underwent an annual health check-up were analyzed in cross-sectional and longitudinal studies.

RESULTS

After adjustment for covariate factors, a multivariate logistic regression analysis showed that age, systolic blood pressure, diastolic blood pressure, LDL-cholesterol, triglyceride, HbA1c, and uric acid (hazard ratio: 1.66) were independently and significantly associated with CKD. We also analyzed the data of 1,652 subjects who underwent annual health check-ups for 5 consecutive years. Over that 5-year period, 93 subjects developed CKD. We compared the baseline data of the subjects who developed CKD with the data of those who did not, and we found significant between-group differences in gender, age, HDL-cholesterol, the estimated glomerular filtration rate, and uric acid. After adjustment for several covariate factors, a multivariate Cox regression analysis showed that only age and hyperuricemia (hazard ratio: 1.36) were independent risk factors for the development of CKD.

CONCLUSIONS

We found that hyperuricemia is an independent risk factor for the development of CKD.

Relationship between estimated glomerular filtration rate, albuminuria, and oxidant status in the Japanese population

Background

In the general population, reported levels of oxidative stress and antioxidant potential seem to vary. The aim of this study was to investigate the levels of oxidant status markers in relation to estimated glomerular filtration rate (eGFR) and albuminuria in Japanese population.

Methods

Data were analyzed from 8335 individuals who underwent a general health screening test. For the estimation of albuminuria, urinary albumin-to-creatinine ratio (UAER) was calculated. Oxidant status was determined by assessing derivatives of reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP).

Results

After adjusting for age, high blood pressure, depressor agent use, CRP, smoking status, multivariate logistic regression analysis showed that the lowest eGFR quartile was associated negatively with the top d-ROM quartile in men (odds ratio 0.78 [95% CI 0.62-0.98, P = 0.034]) and the highest UAER was associated with the top d-ROM in men (odds ratio 1.68) [95% CI 1.35-2.10, P < 0.001]. In addition, both the first eGFR quartile and the fourth UAER quartile showed significant positive association with low BAP levels in men, but not in women.

Conclusions

Among men who underwent general health screening, lower eGFR and increased albuminuria was negatively and positively, respectively, associated with higher oxidative stress levels, whereas both conditions were positively associated with lower antioxidant potential levels.

Reduction of visceral fat correlates with the decrease in the number of obesity-related cardiovascular risk factors in Japanese with Abdominal Obesity (VACATION-J Study)

AIM

Visceral fat accumulation is associated with obesity-related cardiovascular risk factor accumulation and atherosclerosis. The present study investigated whether one-year reduction of the visceral fat area (VFA) correlates with a decrease in the number of such factors in Japanese with or without visceral fat accumulation.

METHODS

The study subjects comprised 5,347 Japanese, who underwent health check-ups in 2007 and 2008, including measurements of VFA and subcutaneous fat area (SFA) by computed tomography at 9 centers in Japan. Subjects with one or more such factor(s) were categorized into tertiles based on the one-year change in VFA. We investigated the multivariate age, sex, and one-year change in SFA-adjusted odds ratios (ORs) and 95% confidence intervals (CI) for reductions in the number of risk factors in each of the three categories based on the one-year change in VFA, in subjects with one or more such factors (n= 3,648).

RESULTS

In the entire group (n=3,648), the OR and 95%CI for reductions in the number of risk factors in the first tertile were 0.804 (0.673-0.962, p=0.0172), compared with the second tertile set at 1.0. Subjects with VFA <100cm(2) showed no reduction in the number of risk factors. In subjects with VFA≥100 cm(2), OR in the first tertile was 0.788 (0.639-0.972, p=0.0257) relative to the second tertile set at 1.0.

CONCLUSIONS

In subjects with multiple cardiovascular risk factors, visceral fat reduction correlated with a decrease in the number of such factors in subjects with VFA≥100cm(2), but not in those with VFA<100cm(2).

Exercise motivation, self-efficacy, and enjoyment as indicators of adult exercise behavior among the transtheoretical model stages

To better understand the role of motivation in determining exercise participation at the population level, we performed a questionnaire survey of 385 Japanese adults (mean age: 55.0 years, SD: 10.9 years). At baseline, the motivation subscales (intrinsic motivation, identified regulation, and external regulation), self-efficacy, and enjoyment all showed significant differences across the stages of change for exercise. Intrinsic motivation and enjoyment had similar findings, with the highest scores being noted in the maintenance stage. Among the 385 subjects, 183 completed the follow-up questionnaire 3 months later. After 3 months, most of the participants (86.9%) who were in the maintenance stage at baseline remained in the same stage. The number of participants who dropped to a lower stage after 3 months was 23. The changes of exercise stage over the 3-month period differed significantly for identified regulation, introjected regulation, and motivation. There were significant time and group interactions for intrinsic motivation and identified regulation. These findings suggest the importance of intrinsic motivation and identified regulation for performance of regular exercise, as well as the role of introjected regulation for promoting behavioral change among Japanese adults.

Absolute value of visceral fat area measured on computed tomography scans and obesity-related cardiovascular risk factors in large-scale Japanese general population (the VACATION-J study)

BACKGROUND

The management of cardiovascular risk factors is important for prevention of atherosclerotic cardiovascular diseases (ACVD). Visceral fat accumulation plays an important role in the clustering of cardiovascular risk factors, leading to ACVD. The present study investigated the gender- and age-specific relationship between obesity-related cardiovascular risk factor accumulation and computed tomography (CT)-measured fat distribution in a large-scale Japanese general population.

METHODS AND RESULTS

Fat distribution was measured on CT scans in 12,443 subjects (males/females = 10,080/2,363), who underwent medical health check-up at 9 centers in Japan. The investigated obesity-related cardiovascular risk factors were hyperglycemia, dyslipidemia, and elevated blood pressure. Visceral fat area (VFA) for all males and old females showed almost symmetric distribution, while that of young females showed skewed distribution with a marked left shift. Only a small proportion of young females had large visceral fat and cardiovascular risk accumulation. The mean number of risk factors exceeded 1.0 at around 100 cm(2) for VFA in all groups, irrespective of gender, age (cut-off age 55), and BMI (cut-off BMI 25 kg/m(2)).

CONCLUSIONS

In this large-scale Japan-wide general population study, an absolute VFA value of about 100 cm(2) equated with obesity-related cardiovascular risk factor accumulation, irrespective of gender, age, and BMI.

Plasma amino acid profile is associated with visceral fat accumulation in obese Japanese subjects

What is already known about this subject •  Asians with metabolic complications associated with obesity, a low body mass index and a low waist circumference have a greater proportion of visceral adipose tissue for a given amount of total body fat compared with Europeans. •  Apparent obese humans and obese animal models show an elevation of branched-chain amino acid levels in plasma. •  A multivariate logistic regression model of plasma free amino acids has been used to screen for several types of cancers in clinical settings. What this study adds •  A specific formula incorporating six amino acid values (Ala, Gly, Glu, Trp, Tyr and branched-chain amino acid) was developed for discrimination of subjects with high visceral fat area by multivariate logistic regression analyses. •  The generated amino acid formula was strongly correlated with visceral fat area in both apparent and non-apparent obese subjects. •  Measuring plasma free amino acids can be used to distinguish the non-apparent visceral obesity in clinical settings in Asian populations.

SUMMARY

Metabolic complications associated with obesity are becoming more common among Japanese subjects. However, visceral fat accumulation is not always apparent by measuring body mass index (BMI) or waist circumference in Asian populations because of the physiological characteristics particular to those ethnicities. Excess visceral fat accumulation raises the odds ratio for developing cardiovascular disease. Thus, high-throughput determination of the amount of abdominal adipose tissue is necessary. We hypothesized that accumulating visceral fat alters the peripheral amino acid profile and that a multivariate logistic regression model of plasma free amino acids can distinguish visceral obesity. A total of 1449 Japanese subjects (985 males and 464 females) who had undergone a comprehensive health screening were enrolled in this study. The visceral fat area was determined using computed tomography imaging, and a plasma free amino acid index to identify high visceral fat areas (≥100 cm(2) ) was developed. The sensitivity and specificity values of the generated amino acid index were 80% and 65%, respectively. In particular, the sensitivity of the generated index to identify subjects with non-apparent visceral obesity (BMI < 25 kg m(-2) ; visceral fat area ≥ 100 cm(2) ) was much greater than that of the waist circumference (73% vs. 46%, respectively). This index's high sensitivity and specificity may be the result of specific alterations in the patients' amino acid profiles, which were specifically correlated with the visceral fat areas and not with subcutaneous fat areas. This profile can be used as a predictor of elevated visceral obesity and a risk assessment tool for metabolic complications in Asian populations.

Changes in waist circumference and body mass index in relation to changes in serum uric acid in Japanese individuals

OBJECTIVE

Studies have shown that obesity is associated with an increase in serum uric acid; and few data are available on the relationship between changes in measures of obesity and changes in uric acid concentrations. We investigated the relationship among percentage changes in waist circumference (%dWC), body mass index (%dBMI), and serum uric acid (%dUA).

METHODS

The data of 3153 individuals [1968 men, 1185 women (536 premenopausal, 649 postmenopausal)] who underwent general health screening over a 2-year period and were not taking antihyperuricemic medication were analyzed.

RESULTS

Stepwise multiple regression analysis showed that %dBMI was associated positively with %dUA in postmenopausal women and men, and the association retained statistical significance after adjustment for changes in blood pressure and in renal function. Association between %dBMI and %dUA was not significant in premenopausal women. In men, %dWC was a predicting factor for %dUA, although it did not remain significant when %dBMI was used as a covariate in the statistical model. Multivariate logistic regression analysis showed that the odds ratio of the association between the lowest %dBMI quartile (%dBMI < -1.86) and the lowest %dUA quartile (%dUA < -7.41) was 2.04 (95% CI 1.35-3.07) in postmenopausal women and 1.46 (95% CI 1.14-1.86) in men.

CONCLUSION

Weight loss may represent an effective nonmedical strategy for reducing serum UA levels, especially in postmenopausal women and men.

Association between changes in obesity parameters and incidence of chronic kidney disease in Japanese individuals

Obesity increases the risk for chronic kidney disease (CKD). By analyzing data on individuals who underwent general health screening in two consecutive years, we investigated whether changes in body mass index (BMI) or waist circumference (WC) were associated with the appearance or disappearance of the CKD components; micro-/macroalbuminuria (> or =30 mg urinary albumin per gram creatinine) and a low estimated glomerular filtration rate (eGFR; <60 ml/min/1.73 m(2)). Logistic regression analysis showed that in men with micro-/macroalbuminuria at the first visit, a BMI reduction of > or =0.42 or a WC reduction of > or =3.0 cm over the 1-year period resulted in a significantly reduced incident of micro-/macroalbuminuria at the second visit. On the other hand, a BMI gain of > or =0.33 over 1 year in men without micro-/macroalbuminuria and a low eGFR at the fist visit significantly increased the incident of micro-/macroalbuminuria and a low eGFR, respectively, at the second visit. These findings indicate that lowering the obesity indexes in men with micro-/macroalbuminuria reduced the incidence of this condition at the 1-year follow-up and that, on the contrary, an increase in BMI in men without micro-/macroalbuminuria and a low eGFR at the first examination increased the risk of these conditions during the 1-year follow-up period.

Impacts of Changes in Obesity Parameters for the Prediction of Blood Pressure Change in Japanese Individuals

<i>Aims and Methods:</i> By analyzing data from 2,861 individuals who underwent general health screening 2 years running, we have investigated the impact of changes in waist circumference (WC) and body mass index (BMI) over a 1-year period on systolic blood pressure (BPs). We termed WC, BMI, and BPs at the first visit as WC1, BMI1, and BPs1, respectively, and those at the second visit as WC2, BMI2, and BPs2, respectively. The %dWC, %dBMI, and %dBPs was defined as (WC2 – WC1)/WC1 × 100, (BMI2 – BMI1)/BMI1 × 100, and (BPs2 – BPs1)/BPs1 × 100, respectively. <i>Results:</i> In multivariate regression analysis using age, BPs1, WC1, and %dWC as independent variables, %dWC was a significant predictor for %BPs only in men. %dBMI was a significant predictor for %BPs in both genders when age, BPs1, BMI1, and %dBMI were used as independent variables. Compared with individuals with both %dWC <0 and %dBMI <0, age-adjusted %dBPs was significantly greater in those with both %dWC <0 and %dBMI ≧0; however, it did not significantly differ in those with both %dWC ≧0 and %dBMI <0. <i>Conclusion:</i> Our data suggest that the impact of BMI change might be greater than WC change in terms of BPs change during this short period.

Association between metabolic syndrome and carotid atherosclerosis in individuals without diabetes based on the oral glucose tolerance test

INTRODUCTION

Whether or not metabolic syndrome is predictive of atherosclerotic disorders may depend on the population studied. We investigated whether metabolic syndrome is associated with carotid atherosclerosis in individuals who were shown not to have diabetes mellitus based on results of the 75-g oral glucose tolerance test (OGTT).

METHODS AND RESULTS

Between 1994 and 2003, 3904 individuals underwent general health screening that included the OGTT. Among these 3904 individuals, 3679 had a fasting plasma glucose of <126 mg/dL (subgroup 1), and 3488 had a 2-h post-OGTT glucose value of <200mg/dL (subgroup 2). In both subgroups, metabolic syndrome was found to be a risk factor for carotid plaque and for carotid intima-media thickening in men, and tended to be a risk factor for carotid plaque in women after adjustment for age. Among 3473 individuals who had both a fasting plasma glucose value of <126 mg/dL and a 2-h post-OGTT glucose of <200mg/dL, 2440 did not have hypertension, which was defined as systolic and diastolic blood pressure of <140/90 mmHg and absence of use of anti-hypertensive medication. In these non-diabetic non-hypertensive individuals, the association between metabolic syndrome and carotid plaque or carotid intima-media thickening was not statistically significant even with adjustment only for age.

CONCLUSIONS

In men who did not have impaired fasting glycemia and/or in those without impaired glucose tolerance, metabolic syndrome was a predictor of carotid atherosclerosis after age adjustment, although metabolic syndrome was not found to be a predictor of carotid atherosclerosis when hypertensive individuals were excluded from the study population.

Association between hepatitis B/C viral infection, chronic kidney disease and insulin resistance in individuals undergoing general health screening

AIM

Previous studies have shown that hepatitis B virus (HBV) and hepatitis C virus (HCV) infection may be associated with glomerulonephritis.

METHODS

In the current study, we investigated the possible association between HBV/HCV infection, estimated GFR (eGFR) and albuminuria by analyzing cross-sectional data from individuals undergoing general health screening.

RESULTS

Of 12 535 individuals enrolled, 130 (1.0%) and 72 (0.6%) tested positive for HBV surface antigen and HCV core antigen, respectively. In comparison with hepatitis-negative individuals, the prevalence of low eGFR and albuminuria was significantly greater in individuals with HCV infection, but not in those with HBV infection. Logistic regression analysis adjusted for age, sex, systolic blood pressure and fasting plasma glucose showed that HCV infection was positively associated with low eGFR (odds ratio 1.63 [95% CI 0.95-2.80, P = 0.077] ) and with albuminuria (odds ratio 2.00 [95% CI 1.06-3.76, P = 0.003] ). By contrast, prevalence of neither low eGFR nor albuminuria was greater in individuals with HBV infection than in hepatitis-negative subjects. Further adjustment for either HOMA-IR or serum alanine aminotransferase levels abolished the statistical significance in the association between HCV infection and albuminuria.

CONCLUSION

Our data suggest that although both HCV and HBV infection are associated with increased insulin resistance, the different viruses may have different impacts on chronic kidney disease among Japanese individuals undergoing general health screening.

Relationship between albuminuria, low eGFR, and carotid atherosclerosis in Japanese women

In this cross-sectional study, we have investigated whether chronic kidney disease components were associated with carotid plaque and carotid intima-media thickening in women. Between April 2005 and May 2006, 830 women underwent general health screening including carotid ultrasonography and urinary albumin excretion, and were enrolled in the study. Of these individuals examined, 83 (10%) had albuminuria, 203 (24%) had low estimated GFR (eGFR), and 24 (3%) had both albuminuria and low eGFR. Univariate analysis showed that albuminuria, but not low eGFR, was associated with carotid plaque, and that both albuminuria and low eGFR were positively associated with carotid intima-media thickening. Age-adjusted logistic regression analysis showed that albuminuria was positively associated with carotid plaque with an odds ratio of 2.48 (95% CI 1.49-4.11, p < 0.001). On the other hand, association between albuminuria and carotid intima-media thickening was not statistically significant after age adjustment. Positive association between albuminuria and carotid plaque was present when either hypertension or high fasting glucose was absent. In conclusion, in Japanese women who underwent general health screening, albuminuria, but not low eGFR, was positively associated with carotid plaque.

Relationship between blood pressure and chronic kidney disease in the Japanese population: the lower the better even in individuals without hypertension?

In hypertensive subjects, it has been demonstrated that the lower the blood pressure, the lower the incidence of chronic kidney disease (CKD). However, whether this relationship holds true in individuals without hypertension--that is, in individuals with a blood pressure <140/90 mmHg--remains unknown. This study was performed to assess the relationship between blood pressure and CKD in a Japanese population without hypertension. Among 13,007 Japanese participants in a general health screening, 9,596 (5,691 men and 3,905 women) were found to have either normal blood pressure or prehypertension, and were enrolled in this study. We categorized these individuals' blood pressure into six classes: BP-C1, <90/<65 mmHg; BP-C2, 90-100/65-70 mmHg; BP-C3, 100-110/70-75 mmHg; BP-C4, 110-120/75-80 mmHg; BP-C5, 120-130/80-85 mmHg; and BP-C6, 130-140/85-90 mmHg. Albuminuria was defined as a urinary albumin excretion ratio of > or =30 mg/g. Low estimated glomerular filtration rate (eGFR) was defined as eGFR <60 mL/min/1.73 m2. In men, when BP-C3 was used as a reference, multivariate logistic regression analysis adjusted for age, body mass index, serum lipid profiles, fasting plasma glucose and smoking status showed that BP-C1, BP-C2, BP-C4, BP-C5 and BP-C6 were associated with albuminuria with an adjusted odds ratio of 1.85 (0.53-6.46), 1.22 (0.59-2.51), 1.62 (1.01-2.59), 2.57 (1.64-4.02), and 3.81 (2.44-5.96). In women, the adjusted odds ratios of the risk for albuminuria in BP-C2, BP-C3, BP-C4, BP-C5 and BP-C6, as compared with BP-C1 as a reference, were 1.83 (0.70-4.79), 2.13 (0.84-5.42), 2.80 (1.10-7.14), 2.59 (0.99-6.78), and 3.99 (1.50-10.64). Blood pressure was not significantly associated with low eGFR in either gender. The risk for albuminuria was significantly greater when blood pressure exceeded 110/75 mmHg in both genders.

Association between obesity and chronic kidney disease in Japanese: differences in gender and hypertensive status?

Obesity is a known risk factor for hypertension and diabetes, both of which ultimately promote renal dysfunction. In the current study, we investigated the association between body mass index (BMI) and chronic kidney disease (CKD) in 8,168 Japanese individuals (2,924 women, 5,244 men) who underwent general health screening. CKD was diagnosed if the estimated glomerular filtration rate (eGFR) was less than 60 mL/min/1.73 m(2) (designated as low eGFR) and/or if the urinary albumin/creatinine value was equal to or greater than 30 mg/g (designated as albuminuria). Logistic regression analysis adjusted for age, systolic blood pressure, fasting glucose, and smoking habits showed that, in men, both overweight (BMI 25-29 kg/m(2)) and obesity (BMI >or=30 kg/m(2)) were associated with increased prevalence of low eGFR and albuminuria, whereas, in women, obesity was associated with albuminuria, but neither overweight nor obesity was associated with low eGFR. After multivariate adjustment, logistic regression analysis showed that BMI had a graded association with both low eGFR and albuminuria in men. On the other hand, in women, the second and third BMI quartiles were associated with a lower prevalence of albuminuria in comparison with the first BMI quartile. Essentially the same results were obtained when the subjects were subdivided according to the presence and absence of hypertension. Our data showed that overweight and obesity were associated with increased risk for CKD in Japanese individuals undergoing a general health screening, irrespective of the presence or absence of hypertension, although there was a gender difference in these associations.

Association between chronic kidney disease and carotid intima-media thickening in individuals with hypertension and impaired glucose metabolism

We investigated whether chronic kidney disease (CKD) was associated with carotid intima-media thickening in 1,351 male individuals undergoing general health screening. Glomerular filtration rate (GFR) was estimated by the Modification of Diet in Renal Disease equations using 0.881 as a coefficient for Japanese, and low estimated GFR (eGFR) was defined as an eGFR value of <60 mL/min/1.73 m(2). Albuminuria was defined as a urine albumin-to-urine creatinine ratio of >or=30 mg/g, and CKD was defined when low eGFR and/or albuminuria was present. After adjusting for age, CKD was associated with carotid intima-media thickening with an odds ratio of 1.47 (95% confidence interval [CI] 1.05-2.06, p=0.0024). After adjusting for age, fasting plasma glucose, and smoking status, both albuminuria and low eGFR were significantly associated with intima-media thickening in individuals with hypertension with an odds ratio of 1.85 (95% CI 1.13-3.03, p=0.015) and 1.79 (95% CI 1.09-2.94, p=0.022), respectively. On the other hand, neither of them was associated with carotid intima-media thickening in individuals without hypertension. Similarly, after adjusting for age, systolic blood pressure, and smoking status, both albuminuria and low eGFR were significantly associated with intima-media thickening in individuals with high fasting glucose (defined as fasting plasma glucose levels of >or=110 mg/dL or current use of anti-diabetic medication), but not in those without. Our data indicate that CKD or its components (low eGFR and albuminuria) may be associated with early carotid atherosclerosis in low-risk individuals, such as those undergoing general health screening, who have hypertension and/or impaired glucose metabolism.

Are serum carcinoembryonic antigen levels associated with carotid atherosclerosis in Japanese men?

OBJECTIVE

Carcinoembryonic antigen (CEA), a serological marker of malignant tumors, may show a modest increase under some nonmalignant conditions, such as ageing and cigarette smoking. We have investigated whether serum CEA levels are associated with early carotid atherosclerosis.

METHODS AND RESULTS

Cross-sectional data from 4181 male individuals who underwent general health screening were analyzed. The interquartile of cutoff values of serum CEA levels were 1.0, 1.6, and 2.5 ng/mL. Cigarette smoking was associated with increased serum CEA levels in a dose- and duration-dependent manner, and this association was more prominent in current than former smokers. Logistic regression analysis adjusted for age, body mass index, serum lipid and glucose profiles, white blood cell count, C-reactive protein, and smoking habits showed that the first, second, third, and fourth CEA quartiles were associated with carotid plaque with an odds ratio of 1 (reference), 1.25 (95% CI 1.03 to 1.52, P=0.023), 1.49 (95% CI 1.23 to 1.82 P<0.001), and 1.34 (95% CI 1.08 to 1.65, P=0.007), respectively. Although serum CEA levels were associated with metabolic syndrome, association between serum CEA and carotid plaque was significant in individuals without metabolic syndrome.

CONCLUSIONS

Serum CEA was associated with carotid atherosclerosis independently of atherogenic risk factors and markers of inflammation. Our data suggest that a slight elevation of CEA in current smokers, as well as in never smokers, may not be an innocuous observation from the viewpoint of atherosclerosis.

Relationship between smoking, white blood cell count and metabolic syndrome in Japanese women

We found that cigarette smoking increased white blood cell count, and individuals which increased white blood cell count more likely to have metabolic syndrome in Japanese men. We investigated whether similar relationship can be observed also in women. We analyzed the data from 16,383 Japanese women who underwent general health screening. Age-adjusted logistic regression analysis showed that current smoking was positively associated with a highest white blood cell count quartile with an odds ratio of 2.40 (95% CI: 2.16-2.68, P<0.0001). The white blood cell count showed a graded association with metabolic syndrome. On the other hand, the association between current smoking and metabolic syndrome was no longer significant after subdividing the individuals into groups according to the white blood cell quartile. These data collectively suggested that the association between current smoking and metabolic syndrome is heavily confounded by certain factors that increase the circulating white blood cell count in Japanese women, as in men.

Is metabolic syndrome a risk factor for carotid atherosclerosis in normotensive and prehypertensive individuals?

AIM

We have investigated whether metabolic syndrome is a risk factor for carotid atherosclerosis also in normotensive or prehypertensive individuals.

METHODS

We analyzed the data from 851 subjects who had a blood pressure of less than 140/90 mmHg and were not taking antihypertensive medication. Metabolic syndrome was defined according to three different criteria: Japan criteria (Japan-MetS); those of the National Cholesterol Education Program (NCEP)-Adult Treatment Panel III (ATP III) (NCEP-MetS); and modified NCEP-ATP III criteria in which body mass index was used as a surrogate for waist circumference (modified NCEP-MetS).

RESULTS

Japan-MetS, NCEP-MetS, and modified NCEP-MetS were found, respectively, in 1%, 4%, and 4%, of women, and in 10%, 5%, and 9%, of men. After the adjustment for gender and age, the association between MetS and carotid atherosclerosis did not reach statistical significance.

CONCLUSION

Although the number of enrolled subjects was relatively small, these data may further support the importance of controlling blood pressure within the optimal range for the purpose of preventing atherosclerosis in individuals with metabolic syndrome.

Higher serum uric acid is associated with increased arterial stiffness in Japanese individuals

Hyperuricemia is postulated to be a risk factor for atherosclerotic diseases, although whether it is independent of classical atherogenic risk factors is controversial. The automatic computer-assisted measurement of brachial-ankle pulse wave velocity (baPWV) is a valid and reproducible method by which to assess arterial stiffness, a potential surrogate marker of early atherosclerosis. By analyzing cross-sectional data from 982 individuals who underwent health screening, we have investigated whether serum uric acid is associated with high baPWV, which was determined as the highest quartile of baPWV values, in a sex-specific manner. Multivariate analysis showed that the odds ratios (95% CI) of the highest baPWV quartile across the sex-specific quartiles of serum uric acid were 1.0, 2.80 (0.93-8.40), 2.13 (0.74-6.19), and 2.76 (1.01-7.55) in women, and 1.0, 1.10 (0.55-2.20), 1.97 (1.04-3.75), and 2.24 (1.10-4.56) in men after adjusting for age, total and HDL-cholesterol, BMI, systolic blood pressure, triglycerides, fasting glucose and smoking status. The association between uric acid and high baPWV was observed in both subjects with metabolic syndrome and those without. These data suggest that in both genders, serum uric acid level is associated with increased baPWV, a marker of arterial stiffness, and is in part independent of other conventional risk factors for atherosclerosis and metabolic syndrome.

Association between cigarette smoking, white blood cell count, and metabolic syndrome as defined by the Japanese criteria

OBJECTIVE

Cigarette smoking increases the circulating white blood cell (WBC) count and the prevalence of metabolic syndrome. We investigated the association between cigarette smoking, WBC count, and metabolic syndrome as defined by the Japanese criteria.

METHOD

Cross-sectional data from 3,687 men undergoing general health screening between 2005 and 2006 were analyzed.

RESULTS

After adjustment for age and total cholesterol, former and current smoking were associated with the highest WBC quartile (>or=6.3 x 10(3) cells/muL) with an odds ratio of 1.35 (95% CI 1.09-1.66, P=0.0055) and 4.45 (95% CI 3.69-5.37, P<0.0001), respectively. It was found that increased WBC count was a risk factor for metabolic syndrome; on the other hand, the current smoking was not found to be a predictor for metabolic syndrome, when each WBC count quartile was separately analyzed.

CONCLUSIONS

Our data suggest that the risk for MetS, defined by Japanese criteria, might be estimated by the WBC count in Japanese men irrespective of their smoking status, although it should also be noted that the cigarette smoking increases the number of circulating WBC count.

HIV-1 Vpr induces ATM-dependent cellular signal with enhanced homologous recombination

An ATM-dependent cellular signal, a DNA-damage response, has been shown to be involved during infection of human immunodeficiency virus type-1 (HIV-1), and a high incidence of malignant tumor development has been observed in HIV-1-positive patients. Vpr, an accessory gene product of HIV-1, delays the progression of the cell cycle at the G2/M phase, and ATR-Chk1-Wee-1, another DNA-damage signal, is a proposed cellular pathway responsible for the Vpr-induced cell cycle arrest. In this study, we present evidence that Vpr also activates ATM, and induces expression of gamma-H2AX and phosphorylation of Chk2. Strikingly, Vpr was found to stimulate the focus formation of Rad51 and BRCA1, which are involved in repair of DNA double-strand breaks (DSBs) by homologous recombination (HR), and biochemical analysis revealed that Vpr dissociates the interaction of p53 and Rad51 in the chromatin fraction, as observed under irradiation-induced DSBs. Vpr was consistently found to increase the rate of HR in the locus of I-SceI, a rare cutting-enzyme site that had been introduced into the genome. An increase of the HR rate enhanced by Vpr was attenuated by an ATM inhibitor, KU55933, suggesting that Vpr-induced DSBs activate ATM-dependent cellular signal that enhances the intracellular recombination potential. In context with a recent report that KU55933 attenuated the integration of HIV-1 into host genomes, we discuss the possible role of Vpr-induced DSBs in viral integration and also in HIV-1 associated malignancy.

Metabolic Syndrome May Not Associate With Carotid Plaque in Subjects With Optimal, Normal, or High-Normal Blood Pressure

Much evidence indicates that metabolic syndrome is a risk factor for the development of cardiovascular disease, but whether metabolic syndrome is an independent risk factor for early atherosclerosis in the individuals with only minor hemodynamic abnormalities, if any, is not well investigated. Here we have investigated the association between metabolic syndrome and carotid atherosclerosis in individuals with blood pressure of <140/90 mm Hg. Between 1994 and 2003, 8143 subjects underwent general health screening including carotid ultrasonography. Of 8143 individuals, 5661 individuals without antihypertensive medications who had blood pressure of <140/90 mm Hg were considered to have optimal, normal, or high-normal blood pressure. After adjustment for age, systolic blood pressure, body mass index, total and high-density lipoprotein cholesterol, triglycerides, fasting glucose, and smoking status, metabolic syndrome was not found to be an independent risk factor for carotid plaque (odds ratio: 1.65; 95% CI; 0.72 to 3.76 in women and odds ratio: 0.95; 95% CI: 0.70 to 1.28 in men) or for carotid intima-media thickening (odds ratio: 0.56; 95% CI: 0.18 to 1.72 in women and odds ratio: 0.93 95% CI: 0.62 to 1.38 in men) in these subjects. Thus, presence of metabolic syndrome may not increase the prevalence of carotid atherosclerosis independent of other cardiovascular risk factors in Japanese individuals with optimal, normal, or high-normal blood pressure.

Association between serum albumin, carotid atherosclerosis, and metabolic syndrome in Japanese individuals

Serum albumin is a maker of nutritional status and possesses antioxidative properties. Here, we have sought to investigate the mode of association between serum albumin levels, metabolic syndrome, and carotid atherosclerosis by analyzing the data of the cross-sectional data from 8143 individuals who underwent general health screening test. After adjusting for age, total cholesterol, and smoking status, the highest quartile of serum albumin (>or=4.7 g/dL) was associated with increased prevalence of metabolic syndrome with an odds ratio of 1.80 (95% CI 1.41-2.23, P<0.0001) in women, and 1.60 (95% CI 1.44-1.78, P<0.0001) in men, when compared to the lowest serum albumin quartile (<4.3g/dL). By contrast, when compared with the lowest quartile, the highest quartile of serum albumin was associated with reduced prevalence of carotid plaque with an odds ratio of 0.62 (95% CI 0.42-0.91, P<0.001) in women, and 0.76 (95% CI 0.62-0.93, P<0.01) in men, and for carotid intima-media thickening with an odds ratio of 0.57 (95% CI 0.35-0.94, P<0.05) in women, and 0.71 (95% CI 0.55-0.92, P<0.01) in men. Our data showed that higher serum albumin was inversely associated with the prevalence of early carotid atherosclerosis, although it was positively associated with the prevalence of metabolic syndrome. Whether these observations are in part explained by the antioxidative properties of albumin requires further investigation.

Association between cigarette smoking, metabolic syndrome, and carotid arteriosclerosis in Japanese individuals

Cigarette smoking is associated with increased insulin resistance and other metabolic abnormalities. Here, we investigate the prevalence of metabolic syndrome (MetS) in cigarette smokers and people who never smoked by analyzing cross-sectional data of 5033 subjects aged between 35 and 65 years who underwent general health screening. Both former and current smoking was associated with an increased incidence of metabolic syndrome defined by modified-National Cholesterol Education Program (NCEP) criteria with odds ratios of 1.77 (95% CI 1.42-2.22, P < 0.0001) and 2.38 (95% CI 1.95-2.91, P < 0.0001), respectively. In both former and current smokers, prevalence of metabolic syndrome increased when the duration of cigarette smoking was > or = 10 years. The positive association between metabolic syndrome and smoking was only partially reversed even 5 years after quitting. Multivariate logistic regression analysis showed that metabolic syndrome was an independent risk factor for carotid plaque with an odds ratio of 1.72 (95% CI 1.43-2.08, P < 0.0001). On the other hand, when limited to individuals without metabolic syndrome, former and current smoking was still found to be associated with carotid plaque with odds ratios of 1.49 (95% CI 1.15-1.92, P = 0.0023) and 1.57 (95% CI 1.22-2.03, P = 0.0005), respectively, in men. Collectively, these data suggest that the atherogenic consequences of smoking may, at least in part, be explained by its association with metabolic syndrome.

Association between serum uric acid, metabolic syndrome, and carotid atherosclerosis in Japanese individuals

OBJECTIVE

There are few data available on possible independent association between uric acid and carotid atherosclerosis. Here we first sought to investigate association between uric acid levels and metabolic syndrome in Japanese; second, we assessed whether there is an independent association of uric acid with prevalence of carotid atherosclerosis in individuals subdivided according to gender and metabolic syndrome status.

METHODS AND RESULTS

Cross-sectional data from 8144 individuals who underwent general health screening were analyzed. After adjusting for age, total cholesterol, and smoking status, the odds ratios (95% CI) of sex-specific quartiles of serum uric acid for metabolic syndrome were 1.0, 1.06 (0.60 to 1.87), 2.18 (1.30 to 3.64), and 4.17 (2.56 to 6.79) in women, and 1.0, 0.92 (0.74 to 1.14), 1.52 (1.25 to 1.65), and 1.97 (1.61 to 2.40) in men. After adjusting for age, serum levels, total cholesterol, and smoking status, prevalence of carotid plaque was higher in subjects in the second, third, and fourth quartiles of uric acid level with odds ratios (95% CI) of 1.24 (1.01 to 1.52), 1.37 (1.11 to 1.68), and 1.31 (1.05 to 1.63), respectively, in men without metabolic syndrome but not in men with metabolic syndrome or in women with or without metabolic syndrome.

CONCLUSIONS

The prevalence of metabolic syndrome showed a graded increase according to serum uric acid values in both genders. In men who did not have metabolic syndrome, uric acid was found to be an independent risk factor for incidence of carotid plaque.

Hypertension Is the Most Common Component of Metabolic Syndrome and the Greatest Contributor to Carotid Arteriosclerosis in Apparently Healthy Japanese Individuals

The cluster of metabolic and hemodynamic risk factors known as metabolic syndrome is known to be a risk factor for ischemic cardiovascular diseases and stroke. By analyzing the cross-sectional data from 8,144 individuals (age 19-88 years) who underwent general health screening, we have investigated the prevalence of metabolic syndrome, as diagnosed by modified-National Cholesterol Education Program (NCEP) criteria corresponding to the following five categories: triglycerides > or = 150 mg/dl; high density lipoprotein (HDL)-cholesterol < 40 mg/dl in men or < 50 mg/dl in women; fasting plasma glucose > or = 110 mg/dl; systolic/diastolic blood pressure > or = 130/85 mmHg; and body mass index > 25 kg/m2. We found that the prevalence of metabolic syndrome was 19% in men and 7% in women. After adjustment for age, metabolic syndrome was found to be significantly more prevalent in men than in women, with an odds ratio of 3.08 (95% confidence interval [CI] 2.62-3.61, p < 0.0001). Among the five metabolic/hemodynamic risk factor components, hypertension was observed most frequently in individuals with metabolic syndrome, at 85% in men and 87% in women. In addition, multivariate logistic regression analysis adjusted for age, sex, serum total cholesterol levels, and smoking status showed that hypertension possessed the greatest odds ratio (1.43, 95% CI 1.27-1.60) for carotid plaque among the metabolic/hemodynamic risk factors. These data emphasize the importance of controlling blood pressure for reducing the risk of both metabolic syndrome and carotid arteriosclerosis in apparently healthy individuals.

Association between white blood cell count and carotid arteriosclerosis in Japanese smokers

Recent studies have shown the relationship between general inflammatory markers and ischemic heart and cerebrovascular diseases. Here we have investigated the potential association between the circulating white blood cell count and carotid arteriosclerosis in apparently healthy individuals. Between 1994 and 1998, 3455 subjects who had undergone general health screening tests including carotid ultrasonography were enrolled in this study. The intertertile cutoff points for the white blood cell count were 5.1 x 10(3) and 6.4 x 10(3) microL(-1) in the male subjects and 4.6 x 10(3) and microL(-1) in the female subjects. The prevalence of carotid plaque in the first (lowest), the second, and the third tertiles was 19, 28, and 28% in the male subjects, respectively (P < 0.0001), and 10, 15, and 14% in the female subjects, respectively (n.s.). The multivariate analysis showed that the male subjects in the second and third tertiles had increased risk for carotid plaque with odds ratios of 1.54 (95% CI 1.18-2.01) and 1.47 (95% CI 1.11-1.95), respectively, compared to those in the first tertile. When male subjects were subdivided according to their smoking status, the association between white blood cell count and carotid plaque was significant in those who smoked, but not in those who had never smoked. These data suggested the possible association between the circulating white blood cell count and formation of carotid plaque in male smokers, but not in male never smokers or in females, in an apparently healthy Japanese population.

Association between insulin resistance and carotid arteriosclerosis in subjects with normal fasting glucose and normal glucose tolerance

OBJECTIVE

We examined the possible association between insulin resistance and carotid arteriosclerosis in subjects who had both normal fasting glucose and normal glucose tolerance after intake of a glucose load.

METHODS AND RESULTS

Our subjects were individuals who underwent general health screening at our institute, which included carotid ultrasound and oral glucose tolerance testing. Of the 1238 subjects enrolled in our study, 738 (60%) were classified as normal, defined as a normal fasting glucose level and normal glucose tolerance, and 334 (27%) and 166 (13%) were classified as borderline and diabetic, respectively, according to the criteria of the Japan Diabetes Society. The homeostasis model assessment of insulin resistance (HOMA-IR) was used as the index to measure insulin resistance. In normal-type subjects, univariate analysis showed that insulin resistance, but not insulin secretion, was associated with the presence of carotid plaque. Multivariate analysis showed that HOMA-IR was positively associated with carotid plaque in normal-type subjects, with an odds ratio of 1.19 (95% confidence interval, 1.00 to 1.41; P<0.05).

CONCLUSIONS

These data suggest the possibility that the presence of higher insulin resistance could be a risk factor for carotid arteriosclerosis in subjects with normal fasting glucose and normal glucose tolerance.