The Relationship of Alcohol Consumption and Drinking Pattern to the Risk of Glomerular Hyperfiltration in Middle-aged Japanese Men: The Kansai Healthcare Study

BACKGROUND

Glomerular hyperfiltration has been reported to be associated with adverse renal outcomes in the general population. It is not known whether drinking pattern is associated with the risk of glomerular hyperfiltration in healthy individuals.

METHODS

We prospectively followed middle-aged 8,640 Japanese men with normal renal function, no proteinuria, no diabetes, and no use of antihypertensive medications at entry. Data on alcohol consumption were gathered by questionnaire. Glomerular hyperfiltration was defined as estimated glomerular filtration rate (eGFR) ≥117 mL/min/1.73 m2, which was the upper 2.5th percentile value of eGFR in the entire cohort.

RESULTS

During 46,186 person-years of follow-up, 330 men developed glomerular hyperfiltration. In a multivariate model, for men who consumed alcohol on 1-3 days per week, alcohol consumption of ≥69.1 g ethanol/drinking day was significantly associated with the risk of glomerular hyperfiltration (hazard ratio [HR] 2.37; 95% confidence interval [CI], 1.18-4.74) compared with non-drinkers. For those who consumed alcohol on 4-7 days per week, higher alcohol consumption per drinking day was associated with a higher risk of glomerular hyperfiltration: the HRs for alcohol consumption of 46.1-69.0, and ≥69.1 g ethanol/drinking day were 1.55 (95% CI, 1.01-2.38), and 1.78 (95% CI, 1.02-3.12), respectively.

CONCLUSION

For high drinking frequency per week, more alcohol intake per drinking day was associated with an increased risk of glomerular hyperfiltration, while for low drinking frequency per week, only very high alcohol intake per drinking day was associated with an increased risk of glomerular hyperfiltration in middle-aged Japanese men.

Body Mass Index and the Risk of Persistent Proteinuria in Middle-Aged Men: The Kansai Healthcare Study

INTRODUCTION

Proteinuria is a risk factor for end-stage renal failure. However, it is not known whether body mass index (BMI) is prospectively associated with the risk of future developing proteinuria, taking into account transient proteinuria.

METHODS

We enrolled 9,320 nondiabetic Japanese middle-aged men who had no proteinuria, an estimated glomerular filtration rate ≥60 mL/min/1.73 m2, no history of cancer, and no use of antihypertensive medications at baseline. "Any proteinuria" was defined as proteinuria detected for the first time during the follow-up period regardless of its frequency. "Persistent proteinuria" was defined as proteinuria that was detected at least twice consecutively at annual examinations and did not return to negative until the end of the follow-up.

RESULTS

During the 11-year follow-up period, 1,972 cases of any proteinuria and 151 cases of persistent proteinuria were confirmed. Both lower and higher BMI were associated with the risk of any proteinuria. As for persistent proteinuria, in those with a BMI ≥20 kg/m2, higher BMI was associated with a higher risk of future persistent proteinuria. The association between BMI and the risk of persistent proteinuria was stronger than that between BMI and any proteinuria. In multiple-adjusted model, hazard ratios of persistent proteinuria for BMI <18.0, 18.0-19.9, 20.0-21.9, 22.0-23.9, 24.0-25.9, 26.0-27.9, and ≥28.0 kg/m2 were 1.52 (95% confidence interval 0.51-4.49), 1.07 (0.49-2.29), 1.00 (reference), 1.14 (0.64-2.01), 1.89 (1.09-3.27), 2.12 (1.15-3.93), and 3.85 (2.03-7.30), respectively.

DISCUSSION/CONCLUSION

In those with a BMI ≥20 kg/m2, higher BMI was associated with a higher risk of future persistent proteinuria and any proteinuria. This relationship was stronger for persistent proteinuria than for any proteinuria.

Serum Gamma-Glutamyltransferase, Daily Alcohol Consumption, and the Risk of Chronic Kidney Disease: The Kansai Healthcare Study

BACKGROUND

Serum gamma-glutamyltransferase has been recognized as the risk factor of cardiovascular and metabolic diseases. However, the association between serum gamma-glutamyltransferase and the risk of chronic kidney disease is not well known, and no prospective studies have examined separately the relationship of serum gamma-glutamyltransferase with the risk of proteinuria versus that of low estimated glomerular filtration rate (eGFR).

METHODS

We prospectively followed 9,341 Japanese men who did not have low eGFR, proteinuria, or diabetes, and did not take antihypertensive medications at entry for the analysis of proteinuria, and we followed 9,299 men for the analysis of low eGFR. We defined "persistent proteinuria" as proteinuria detected two or more times consecutively and persistently as ≥1+ on urine dipstick at the annual check-up until the end of follow-up. Low eGFR was defined as eGFR <60 mL/min/1.73 m².

RESULTS

During the 11-year observation period, 151 men developed persistent proteinuria and 1,276 men developed low eGFR. In multivariate models, the highest quartile (≥71 IU/L) of serum gamma-glutamyltransferase was independently related to the development of persistent proteinuria (hazard ratio 3.39; 95% confidence interval, 1.92-5.97) compared with the lowest quartile (≤25 IU/L). In joint analysis of alcohol consumption and serum gamma-glutamyltransferase, non-drinkers in the highest tertile (≥58 IU/L) of serum gamma-glutamyltransferase had the highest risk of persistent proteinuria. However, there was no association between serum gamma-glutamyltransferase and low eGFR.

CONCLUSION

In middle-aged Japanese men, elevated serum gamma-glutamyltransferase was independently associated with future persistent proteinuria, but not with low eGFR.

Habitual Alcohol Intake Modifies Relationship of Uric Acid to Incident Chronic Kidney Disease

BACKGROUND

Previous studies showed that higher serum uric acid levels increased the risk of chronic kidney disease (CKD), but moderate alcohol consumption decreased it. The comparative importance of serum uric acid levels and habitual alcohol consumption as risk factors for CKD remain undefined. We therefore evaluated the relationship of baseline serum uric acid level in combination with daily alcohol consumption to the incidence of CKD.

METHODS

A prospective cohort study of 9,116 middle-aged nondiabetic -Japanese men without CKD nor proteinuria who were not taking antihypertensive medications nor urate-lowering medications at entry. CKD was defined as estimated glomerular filtration rate <60 mL/min/1.73 m2. We investigated the relationship of baseline serum uric acid level in combination with daily alcohol consumption to the incidence of CKD during an 11-year observation period. Daily alcohol consumption was classified into 4 groups: nondrinkers, light drinkers (0.1-23.0 g ethanol/day), moderate drinkers (23.1-46.0 g ethanol/day), and heavy drinkers (≥46.1 g ethanol/day). Cox proportional hazards models were used in multivariate analysis.

RESULTS

During the 79,361 person-years follow-up period, a total of 1,230 subjects developed CKD. In multivariate models, higher serum uric acid levels increased risk of CKD; and moderate daily alcohol consumption decreased the risk. Multiple-adjusted hazard ratios of CKD were 1.38 (95% CI 1.11-1.70), 1.58 (95% CI 1.28-1.95), 2.27 (95% CI 1.86-2.77), and 3.12 (95% CI 2.56-3.81) for quintile 2, quintile 3, quintile 4, and quintile 5 of serum uric acid levels, respectively, compared with quintile 1, and that for moderate drinkers was 0.55 (95% CI 0.46-0.66) compared with nondrinkers. In the joint analysis of alcohol consumption and serum uric acid, moderate drinkers with the lowest tertile of serum uric acid levels had the lowest risk of CKD, but nondrinkers with the highest tertile of serum uric acid levels had the highest risk of CKD.

CONCLUSIONS

Serum uric acid level and daily alcohol consumption were independently associated with the risk of CKD. Nondrinkers with the highest serum uric acid level had the highest risk of CKD.

Design and validation of a novel estimator of visceral adipose tissue area and comparison to existing adiposity surrogates

AIMS

Visceral adiposity measured by computed tomography (CT) as intra-abdominal fat area (IAFA) predicts metabolic diseases. Existing adiposity surrogates have not been systematically compared to a regression-based model derived in individuals of Japanese ancestry. We developed and validated a method to estimate IAFA in individuals of Japanese ancestry and compared it to existing adiposity surrogates.

METHODS

We assessed age, BMI, waist circumference (WC), fasting lipids, glucose, smoking status, grip strength, mid-thigh circumference (MTC), humeral length, leg length, and IAFA by single-slice CT at the umbilicus for 622 Japanese Americans. We used stepwise linear regression to predict IAFA and termed the predicted value the Estimate of Visceral Adipose Tissue Area (EVA). For men, the final model included age, BMI, WC, high-density lipoprotein cholesterol (HDLc), glucose, and MTC; for women, age, BMI, WC, HDLc, low-density lipoprotein cholesterol, glucose, and MTC. We compared goodness-of-fit (R²) from linear regression models and mean-squared errors (MSE) from k-fold cross-validation to compare the ability of EVA to estimate IAFA compared to an estimate by Després et al., waist-to-height ratio, WC, deep abdominal adipose tissue index, BMI, lipid accumulation product, and visceral adiposity index (VAI). We classified low/high IAFA using area under receiver-operating characteristic curves (AUROC) for IAFA dichotomized at the 75th percentile.

RESULTS

EVA gave the least MSE and greatest R² (men: 1244, 0.61; women: 581, 0.72). VAI gave the greatest MSE and smallest R² (mean 2888, 0.08; women 1734, 0.14).

CONCLUSIONS

EVA better predicts IAFA in Japanese-American men and women compared to existing surrogates for adiposity.

The Association Between Metabolically Healthy Obesity and the Risk of Proteinuria: The Kansai Healthcare Study

Background

Metabolically healthy obesity seems to be a unique phenotype for the risk of cardiometabolic diseases. However, it is not known whether this phenotype is associated with the risk of proteinuria.

Methods

Study subjects were 9,185 non-diabetic Japanese male workers aged 40–55 years who had no proteinuria, an estimated glomerular filtration rate ≥60 mL/min/1.73 m², no history of cancer, and no use of antihypertensive or lipid-lowering medications at baseline. Obesity was defined as body mass index ≥25.0 kg/m². Metabolic health was defined as the presence of no Adult Treatment Panel III components of the metabolic syndrome criteria, excluding waist circumference, and metabolic unhealth was defined as the presence of one or more metabolic syndrome components, excluding waist circumference. “Consecutive proteinuria” was considered positive if proteinuria was detected twice consecutively as 1+ or higher on urine dipstick at annual examinations to exclude chance proteinuria as much as possible.

Results

During the 81,660 person-years follow-up period, we confirmed 390 cases of consecutive proteinuria. Compared with metabolically healthy non-obesity, metabolically healthy obesity was not associated with the risk of consecutive proteinuria (multiple-adjusted hazard ratio [HR] 0.86; 95% confidence interval [CI], 0.37–1.99), but metabolically unhealthy non-obesity with ≥2 metabolic syndrome components (HR 1.77; 95% CI, 1.30–2.42), metabolically unhealthy obesity with one component (HR 1.71; 95% CI, 1.12–2.61), and metabolically unhealthy obesity with ≥2 metabolic syndrome components (HR 2.77; 95% CI, 2.01–3.82) were associated with an increased risk of consecutive proteinuria.

Conclusions

Metabolically healthy obesity did not increase the risk of consecutive proteinuria in Japanese middle-aged men.

Blood pressure components and the risk for proteinuria in Japanese men: The Kansai Healthcare Study

Background

We examined prospectively which of the four blood pressure (BP) components (systolic BP [SBP], diastolic BP [DBP], pulse pressure [PP], and mean arterial pressure [MAP]) was best in predicting the risk of proteinuria.

Methods

This prospective study included 9341 non-diabetic Japanese middle-aged men who had no proteinuria and an estimated glomerular filtration rate ≥60 mL/min/1.73 m² and were not taking antihypertensive medications at entry. Persistent proteinuria was defined if proteinuria was detected two or more times consecutively and persistently at the annual examination until the end of follow-up. We calculated the difference in values of Akaike's information criterion (ΔAIC) in comparison of the BP components-added model to the model without them in a Cox proportional hazards model.

Results

During the 84,587 person-years follow-up period, we confirmed 151 cases of persistent proteinuria. In multiple-adjusted models that included a single BP component, the hazard ratios for persistent proteinuria for the highest quartile of SBP, PP, and MAP were 3.11 (95% confidence interval [CI], 1.79–5.39), 1.87 (95% CI, 1.18–2.94), and 2.21 (95% CI, 1.33–3.69) compared with the lowest quartile of SBP, PP, and MAP, respectively. The hazard ratio for the highest quartile of DBP was 2.69 (95% CI, 1.65–4.38) compared with the second quartile of DBP. Of all models that included a single BP component, those that included SBP alone or DBP alone had the highest values of ΔAIC (14.0 and 13.1, respectively) in predicting the risk of persistent proteinuria.

Conclusions

Of all BP components, SBP and DBP were best in predicting the risk of persistent proteinuria in middle-aged Japanese men.

•

We examined which blood pressure (BP) components increased risk of proteinuria.

•

We used systolic BP, diastolic BP, pulse pressure, and mean arterial pressure.

•

Systolic and diastolic BP were the best predictors of persistent proteinuria.

Investigation of Spatial Clustering of Biliary Tract Cancer Incidence in Osaka, Japan: Neighborhood Effect of a Printing Factory

BACKGROUND

In 2013, an unusually high incidence of biliary tract cancer among current or former workers of the offset color proof printing department of a printing company in Osaka, Japan, was reported. The purpose of this study was to examine whether distance from the printing factory was associated with incidence of biliary tract cancer and whether incident biliary tract cancer cases clustered around the printing factory in Osaka using population-based cancer registry data.

METHODS

We estimated the age-standardized incidence ratio of biliary tract cancer according to distance from this printing factory. We also searched for clusters of biliary tract cancer incidence using spatial scan statistics.

RESULTS

We did not observe statistically significantly high or low standardized incidence ratios for residents in each area categorized by distance from the printing factory for the entire sample or for either sex. The scan statistics did not show any statistically significant clustering of biliary tract cancer incidence anywhere in Osaka prefecture in 2004-2007.

CONCLUSIONS

There was no statistically significant clustering of biliary tract cancer incidence around the printing factory or in any other areas in Osaka, Japan, between 2004 and 2007. To date, even if some substances have diffused outside this source factory, they do not appear to have influenced the incidence of biliary tract cancer in neighboring residents.

Relationship Between Alcohol Drinking Pattern and Risk of Proteinuria: The Kansai Healthcare Study

Background

Moderate alcohol consumption has been reported to be associated with a decreased risk of cardiometabolic diseases. Whether drinking pattern is associated with the risk of proteinuria is unknown.

Methods

Study subjects were 9154 non-diabetic Japanese men aged 40–55 years, with an estimated glomerular filtration rate ≥60 mL/min/1.73 m², no proteinuria, and no use of antihypertensive medications at entry. Data on alcohol consumption were obtained by questionnaire. We defined “consecutive proteinuria” as proteinuria detected twice consecutively as 1+ or higher on urine dipstick at annual examinations.

Results

During the 81 147 person-years follow-up period, 385 subjects developed consecutive proteinuria. For subjects who reported drinking 4–7 days per week, alcohol consumption of 0.1–23.0 g ethanol/drinking day was significantly associated with a decreased risk of consecutive proteinuria (hazard ratio [HR] 0.54; 95% confidence interval [CI], 0.36–0.80) compared with non-drinkers. However, alcohol consumption of ≥69.1 g ethanol/drinking day was significantly associated with an increased risk of consecutive proteinuria (HR 1.78; 95% CI, 1.01–3.14). For subjects who reported drinking 1–3 days per week, alcohol consumption of 0.1–23.0 g ethanol/drinking day was associated with a decreased risk of consecutive proteinuria (HR 0.76; 95% CI, 0.51–1.12), and alcohol consumption of ≥69.1 g ethanol/drinking day was associated with an increased risk of consecutive proteinuria (HR 1.58; 95% CI, 0.72–3.46), but these associations did not reach statistical significance.

Conclusions

Men with frequent alcohol consumption of 0.1–23.0 g ethanol/drinking day had the lowest risk of consecutive proteinuria, while those with frequent alcohol consumption of ≥69.1 g ethanol/drinking day had an increased risk of consecutive proteinuria.

Drinking pattern and risk of chronic kidney disease: the kansai healthcare study

BACKGROUND/AIMS

The association between alcohol consumption and the risk of chronic kidney disease (CKD) has been reported. What is not known is whether drinking pattern combined with the weekly frequency of alcohol consumption and the quantity per drinking day is associated with the risk of CKD.

METHODS

We enrolled 9,112 Japanese nondiabetic men aged 40 to 55 years with absence of proteinuria, an estimated glomerular filtration rate (eGFR) of 60 ml/min/1.73 m(2) or higher, and not on antihypertensive medications at baseline. CKD was defined if eGFR was <60 ml/min/1.73 m(2). The weekly frequency classification was nondrinkers, 1-3 drinking days/week, or 4-7 drinking days/week. The quantity consumed per drinking day was classified as 0.1-23.0 g ethanol/drinking day, 23.1-46.0 g ethanol/drinking day, 46.1-69.0 g ethanol/drinking day, and ≥69.1 g ethanol/drinking day.

RESULTS

During the 79,099 person-years, 1,253 subjects developed CKD. Compared to nondrinkers, those who consumed 23.1-46.0 or 46.1-69.0 g ethanol/drinking day on 4-7 drinking days/week had a decreased risk of CKD (multiple-adjusted hazard ratio (HR) 0.62 (0.52-0.74) and 0.76 (0.59-0.97), respectively). The association between the quantity per drinking day and the incidence of CKD was U-shaped among each category of the weekly frequency. HRs within similar categories of quantity per drinking day were lower in the 4-7 drinking days/week group than in the 1-3 drinking days/week group.

CONCLUSION

Among middle-aged Japanese men, the people who drank middle-range quantity, specifically who drank 4-7 days/week, had lower risk of CKD than nondrinkers.

Sleep duration and the risk of future lipid profile abnormalities in middle-aged men: the Kansai Healthcare Study

BACKGROUND

Although short sleep duration has been reported to be associated with future cardiometabolic diseases, it is not fully understood whether sleep duration is prospectively associated with the risk of each lipid profile abnormality.

METHODS

Subjects were nondiabetic Japanese, 40-55 years of age, who were not taking oral lipid-lowering medications: for the incidence of low high-density lipoprotein cholesterol (HDL-C), 7627 men with an HDL-C level ≥ 40 mg/dL; for high triglycerides, 6973 men with a triglyceride level <200 mg/dL; for high low-density lipoprotein cholesterol (LDL-C), 7273 men with an LDL-C level <160 mg/dL; for high non-HDL-C, 7415 men with a non-HDL-C level <190 mg/dL; and for high total cholesterol (TC), 7196 men with a TC level <240 mg/dL. Lipid profile abnormalities were defined according to the Adult Treatment Panel III guidelines of the National Cholesterol Education Program.

RESULTS

During the 6-year observation period, there were 1022 cases of low HDL-C. Multiple-adjusted hazard ratios for low HDL-C were 0.79 (95% confidence interval, 0.64-0.97) for sleep durations of 5 to <7 h and 0.62 (0.46-0.83) for ≥ 7 h compared with <5 h. There were 1473 cases of high triglycerides. Multiple-adjusted hazard ratios for high triglycerides were 0.81 (0.68-0.98) for sleep durations of 5 to <7 h and 0.90 (0.72-1.13) for ≥ 7 h compared with <5 h. However, no association between sleep duration and the risk of future high LDL-C, non-HDL-C, or TC was observed.

CONCLUSIONS

Moderate and/or long sleep durations decreased the risk of future low HDL-C and high triglycerides.

Fasting tests of insulin secretion and sensitivity predict future prediabetes in Japanese with normal glucose tolerance

Aims/Introduction:  Reduced insulin sensitivity and secretion are important in the pathogenesis of type 2 diabetes. Their relationships to prediabetes, impaired glucose tolerance (IGT) and impaired fasting glucose (IFG) have been previously studied with the oral glucose tolerance test (OGTT). We investigated whether or not baseline measures of insulin secretion and sensitivity obtained from fasting blood specimens were related to the development of prediabetes and how these measures compared with those based on the OGTT.

Materials and Methods:  In 152 Japanese subjects with normal glucose tolerance, we measured baseline plasma glucose and insulin after an overnight fast and during a 75 g OGTT, insulin resistance index (homeostasis model assessment [HOMA‐IR]), and insulin secretion (insulinogenic index [30 min insulin − fasting insulin] ÷ [30 min glucose − fasting glucose] or HOMA‐β).

Results:  At a 5–6 year (mean 5.7 years) follow‐up examination, we confirmed 36 cases of prediabetes. After adjusting for age, sex, family history of diabetes, body mass index, and 2‐h plasma glucose, the odds ratio comparing the lowest tertile (≤0.82) of insulinogenic index with the highest tertile (≥1.43) was 6.98 (95% confidence interval, 1.96–24.85) and was 10.72 (2.08–55.3) comparing the lowest tertile (≤76.3) of HOMA‐β with the highest tertile (≥122.1), whereas the respective odds ratios of HOMA‐IR were 3.74 (1.03–13.57) and 10.89 (1.93–61.41) comparing the highest tertile (≥1.95) with the lowest tertile (≤1.25).

Conclusions:  Lower insulin secretion and sensitivity are independent risk factors for prediabetes. Clinically practical identification of those at risk for prediabetes is obtainable from HOMA‐β and HOMA‐IR, both of which are measured in fasting state. (J Diabetes Invest, doi: 10.1111.j.2040‐1124.2010.00041.x, 2010)

Serum butyrylcholinesterase and the risk of future type 2 diabetes: the Kansai Healthcare Study

OBJECTIVE

Butyrylcholinesterase is synthesized in the liver. The serum butyrylcholinesterase level has been cross-sectionally reported to be higher in patients with diabetes, hyperlipidaemia, obesity and fatty liver than in those without them. It is not known whether serum butyrylcholinesterase is associated with the risk of future type 2 diabetes.

DESIGN

A prospective cohort study.

PARTICIPANTS

A total of 8470 Japanese men aged 40-55 years without type 2 diabetes at baseline.

MEASUREMENTS

Type 2 diabetes was diagnosed if a fasting plasma glucose (FPG) level was ≥7·0 mmol/l, if a HbA1 c level was ≥6·5% or if participants were taking oral hypoglycaemic medication or insulin.

RESULTS

During the 42,227 person-years of follow-up, 868 cases had developed type 2 diabetes. Serum butyrylcholinesterase was significantly positively correlated with body mass index (BMI), FPG, alanine aminotransferase (ALT), γ-glutamyltransferase (GGT) and triglycerides (TG), whereas negatively with high-density lipoprotein (HDL) cholesterol. In Cox proportional hazards models, after adjusting for age, BMI, FPG, alcohol consumption, smoking habit, walk to work, regular leisure-time physical activity and family history of diabetes, the highest quartile (398-806 IU/l) of serum butyrylcholinesterase increased the risk of type 2 diabetes compared with the lowest quartile (56-311 IU/l) [hazard ratio (HR) 1·41 (95% confidence interval (CI), 1·14-1·74)]. After further adjusting for ALT and GGT, this association remained [HR 1·40 (95% CI, 1·13-1·73)]. Furthermore, this association was significant independent of TG and HDL cholesterol.

CONCLUSIONS

Elevated serum butyrylcholinesterase was independently associated with an increased risk of future type 2 diabetes.

Patterns of insulin concentration during the OGTT predict the risk of type 2 diabetes in Japanese Americans

OBJECTIVE

To examine whether the patterns of insulin concentration during the oral glucose tolerance test (OGTT) predict type 2 diabetes.

RESEARCH DESIGN AND METHODS

We followed 400 nondiabetic Japanese Americans for 10-11 years. Insulin concentrations at 30, 60, and 120 min during a 2-h 75-g OGTT at baseline were used to derive the following possible patterns of insulin: pattern 1 (30-min peak, higher insulin level at 60 than at 120 min), pattern 2 (30-min peak, lower or equal level at 60 vs. 120 min), pattern 3 (60-min peak); pattern 4 (120-min peak, lower level at 30 than at 60 min), and pattern 5 (120-min peak, equal or higher level at 30 vs. 60 min). Insulin sensitivity was estimated by homeostasis model assessment of insulin resistance (HOMA-IR) and Matsuda index. Insulin secretion was estimated by the insulinogenic index (IGI) [Δinsulin/Δglucose (30-0 min)] and disposition index (IGI/HOMA-IR).

RESULTS

There were 86 incident cases of type 2 diabetes. The cumulative incidence was 3.2, 9.8, 15.4, 47.8, and 37.5% for patterns 1, 2, 3, 4, and 5, respectively. Compared with pattern 1, patterns 4 and 5, characterized by a lasting late insulin response, were associated with significantly less insulin sensitivity as measured by the Matsuda index and lower early insulin response by the disposition index. The multiple-adjusted odds ratios of type 2 diabetes were 12.55 (95% CI 4.79-32.89) for pattern 4 and 8.34 (2.38-29.27) for pattern 5 compared with patterns 1 and 2. This association was independent of insulin secretion and sensitivity.

CONCLUSIONS

The patterns of insulin concentration during an OGTT strongly predict the development of type 2 diabetes.

Serum adiponectin and bone mineral density in male hemodialysis patients

SUMMARY

Bone mineral density of the 1/3 distal radius, ultra-distal radius, and lumbar spine correlated significantly and negatively with serum adiponectin. There was a significant positive correlation between serum adiponectin and serum NTX. Thus, adiponectin may play a role in mineral and bone disorder in chronic kidney disease stage 5 dialysis (CKD 5D) patients.

INTRODUCTION

Serum adiponectin, an adipocyte-produced hormone, has been reported to correlate negatively with bone mineral density (BMD) in the general population. However, little is known about the association between adiponectin and BMD in patients with CKD.

METHODS

BMD of the 1/3 distal and ultra-distal radius, which are enriched with cortical and cancellous bone, respectively, and the lumbar spine was measured by dual X-ray absorptiometry in 114 Japanese male hemodialysis patients (age 61.0 ± 11.1 years; hemodialysis duration 6.6 ± 3.0 years; 43.9% diabetics). Serum total adiponectin, bone formation marker (bone alkaline phosphatase, BAP), and bone resorption marker (cross-linked N-telopeptide of type I collagen (NTX)) were measured.

RESULTS

The BMD of the 1/3 distal radius, ultra-distal radius, and lumbar spine correlated significantly and negatively with serum adiponectin level (r = -0.229, p = 0.014; r = -0.286, p = 0.002; r = -0.227, p = 0.013, respectively). In multiple linear regression analyses, serum adiponectin was significantly and independently associated with the BMD of the 1/3 distal radius (R(2) = 0.173, p < 0.001) and ultra-distal radius (R(2) = 0.278, p < 0.001) after adjustment of age, hemodialysis duration, body weight, %fat mass, and log [intact PTH], although it was not with the BMD of the lumbar spine. There was a significant positive correlation between serum adiponectin and serum NTX (r = 0.321, p < 0.001), although there was no significant correlation between serum adiponectin and serum BAP.

CONCLUSION

Increased levels of serum adiponectin were associated with decrease in BMD in male hemodialysis patients. Adiponectin may play a role in mineral and bone disorder, possibly in bone resorption, of patients with CKD 5D.

Gestational bodyweight gain among underweight Japanese women related to small-for-gestational-age birth

AIM

The prevalence of underweight women, who have an increased risk for small-for-gestational-age (SGA) birth, is increasing in Japan. We examined the associations of pre-pregnancy body mass index and gestational weight gain (GWG) with SGA birth among Japanese women.

MATERIAL AND METHODS

We conducted a prospective cohort study of 1391 women who delivered full-term singleton babies. SGA was defined as below the 10th percentile of birthweight at each gestational age, baby sex, and parity. We calculated the 5th percentile of birthweight in the same way for another threshold for SGA. According to pre-pregnancy body mass index, we divided the participants into three groups: underweight (<18.5 kg/m(2)), normal weight (18.5-24.9 kg/m(2)), and overweight and obese (≥25.0 kg/m(2)).

RESULTS

SGA birth was observed most frequently among the underweight group (13.8%). Underweight was associated with an increased risk of SGA birth. The multiple-adjusted odds ratio for underweight was 1.96 (95% confidence interval, 1.23-3.11) compared with normal weight. Sufficient GWG reduced the incidence and the multiple-adjusted odds ratio for 1-kg increase of GWG was 0.86 (0.81-0.92). The same tendency was observed for the delivery of infants below the 5th birthweight percentile. Women with underweight and normal weight who had 9.0 kg or less of GWG had a significantly higher risk of SGA birth than women with normal weight who had 9.1-11.0 kg of GWG.

CONCLUSIONS

Underweight and poor GWG were associated with a higher incidence of SGA birth. However, the incidence of SGA birth among underweight women was not increased significantly if they had sufficient GWG.

Tonsillectomy has beneficial effects on remission and progression of IgA nephropathy independent of steroid therapy

BACKGROUND

Indication of tonsillectomy in IgA nephropathy is controversial. The purpose of this study was to examine the efficacy of tonsillectomy on remission and progression of IgA nephropathy.

METHODS

We conducted a single-center 7-year historical cohort study in 200 patients with biopsy-proven IgA nephropathy. Study outcomes were clinical remission defined as disappearance of urine abnormalities at two consecutive visits, glomerular filtration rate (GFR) decline defined as 30% GFR decrease from baseline and GFR slope during the follow-up.

RESULTS

Seventy of the 200 patients received tonsillectomy. Tonsillectomy was associated with increased incidence of clinical remission (P+0.01, log-rank test) and decreased incidence of GFR decline (P=0.01, log-rank test). After adjustment for age and gender, hazard ratios in tonsillectomy were 3.90 (95% confidence interval 2.46-6.18) for clinical remission and 0.14 (0.02-1.03) for GFR decline. After further adjustment for laboratory (baseline mean arterial pressure, GFR, 24-h proteinuria and hematuria score), histological (mesangial score, segmental sclerosis or adhesion, endocapillary proliferation and interstitial fibrosis) or treatment variables (steroid and renin-angiotensin system inhibitors), similar results were obtained in each model. Even after exclusion of 69 steroid-treated patients, results did not change. GFR slopes in tonsillectomy and non-tonsillectomy groups were 0.60±3.65 and -1.64±2.59 mL/min/1.73 m2/year, respectively. In the multiple regression model, tonsillectomy prevented GFR decline during the follow-up period (regression coefficient 2.00, P=0.01).

CONCLUSION

Tonsillectomy was associated with a favorable renal outcome of IgA nephropathy in terms of clinical remission and delayed renal deterioration even in non-steroid-treated patients.

Cigarette smoking and the association with glomerular hyperfiltration and proteinuria in healthy middle-aged men

BACKGROUND AND OBJECTIVES

Glomerular hyperfiltration and albuminuria accompanied by early-stage diabetic kidney disease predict future renal failure. Cigarette smoking has reported to be associated with elevated GFR in cross-sectional studies and with renal deterioration in longitudinal studies. The degree of glomerular hyperfiltration and proteinuria associated with smoking, which presumably is a phenomenon of early renal damage, has not been investigated in a satisfying manner so far.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This study included 10,118 Japanese men aged 40 to 55 years without proteinuria or renal dysfunction at entry. Estimated GFR was calculated using the Modification of Diet in Renal Disease equation for Japanese. Glomerular hyperfiltration was defined as estimated GFR ≥117.0 ml/min per 1.73 m(2), which was the upper 2.5th percentile value of estimated GFR in the total population. Proteinuria was detected using standard dipstick.

RESULTS

During the 6-year observation period, there were 449 incident cases of glomerular hyperfiltration and 1653 cases of proteinuria. Current smokers had a 1.32-time higher risk for the development of glomerular hyperfiltration and a 1.51-time higher risk for proteinuria than nonsmokers after adjustment for baseline age, body mass index, systolic and diastolic BP, antihypertensive medication, diabetes, alcohol consumption, regular leisure-time physical activity, and estimated GFR. Both daily and cumulative cigarette consumption were associated with an increased risk for glomerular hyperfiltration and proteinuria in a dose-response manner.

CONCLUSIONS

In middle-aged Japanese men, smoking was associated with an increased risk of glomerular hyperfiltration and dipstick proteinuria. Of importance, past smokers did not exhibit any increased risk for these conditions.

Elevated white blood cell count worsens proteinuria but not estimated glomerular filtration rate: the Kansai Healthcare Study

BACKGROUND/AIMS

No prospective studies have estimated the association between white blood cell (WBC) count and the risk of proteinuria. We prospectively examined the relationships of WBC count, as a marker of inflammation, with two outcomes: proteinuria and low estimated glomerular filtration rate (eGFR).

METHODS

We enrolled 10,008 Japanese men aged 40-55 years who had neither proteinuria nor low eGFR and were not taking antihypertensive medications at entry. Proteinuria was defined as 1+ or higher on urine dipstick. Low eGFR was defined if eGFR was <60 ml/min/1.73 m(2).

RESULTS

During the 49,644 person-years of follow-up, 1,557 cases of proteinuria were confirmed. After adjusting for age, body mass index, fasting plasma glucose, systolic blood pressure, diastolic blood pressure, antidiabetic medications, alcohol consumption, smoking, regular leisure-time physical activity and eGFR, the highest quintile (≥7.51 × 10(3)/μl) of WBC count was independently associated with an increased risk of incidence of proteinuria [HR: 1.45 (95% CI: 1.23-1.73)] compared with the lowest quintile (≤4.80 × 10(3)/μl). On the other hand, during 52,833 person-years, we confirmed 439 cases of low eGFR. In multivariate models, there was no association between WBC count and low eGFR.

CONCLUSION

Elevated WBC count was independently associated with an increased risk of proteinuria, but not low eGFR.

Blood pressure components and risk for chronic kidney disease in middle-aged Japanese men: The Kansai Healthcare Study

It is unclear which blood pressure (BP) components (that is, systolic BP (SBP), diastolic BP (DBP), pulse pressure (PP) and mean arterial pressure (MAP)) are superior predictors of chronic kidney disease (CKD). Furthermore it is unclear whether the combination of SBP+DBP or PP+MAP is superior to any of these four individual BP components in predicting CKD. We enrolled 9928 Japanese men aged 40-55 years who had a normal estimated glomerular filtration rate (eGFR), no proteinuria and no history of cardiovascular disease and were not taking any antihypertensive medications at baseline. CKD was defined as an eGFR of <60 ml min(-1) per 1.73 m(2) using the modified diet in renal disease equation. ΔAkaike's information criterion (ΔAIC) was used to compare the BP components-added model to the model without them in a Cox proportional hazards model. During the 52 428 person-years of follow-up, there were 434 cases of CKD. Of all four BP components, the model including DBP- or MAP-alone had the highest values of ΔAIC (10.2 and 9.85, respectively). The PP-alone model had the lowest ΔAIC value (-1.48). The combination models including SBP+DBP (ΔAIC 8.42) or PP+MAP (8.42) were not superior to the models including DBP- or MAP-alone. These findings suggested that, of the four BP components, both DBP and MAP were the most useful predictors for subsequent incidence of CKD, but PP was not an important predictor. The combination model, including SBP+DBP or PP+MAP, was not superior to the models including DBP- or MAP-alone for predicting CKD.

Relationship between drinking patterns and the risk of type 2 diabetes: the Kansai Healthcare Study

BACKGROUND

Moderate alcohol consumption is associated with a decreased risk of type 2 diabetes. However, the relationship between drinking patterns, such as the weekly frequency of alcohol consumption and the quantity per drinking day, and the incidence of type 2 diabetes has not been sufficiently addressed.

METHODS

Study participants included 10 631 Japanese men aged 40-55 years without type 2 diabetes at entry. Type 2 diabetes was diagnosed if a fasting plasma glucose level was ≥7.0 mmol/l or if participants were taking diabetes medications. Data on alcohol consumption were obtained from questionnaires.

RESULTS

During the 37 172 person-years of follow-up, we confirmed 878 cases of type 2 diabetes. Frequent alcohol consumption was associated with a low risk of type 2 diabetes. Compared to non-drinkers, the multiple-adjusted HR for those who drank 4-7 days weekly was 0.76 (95% CI, 0.63 to 0.92). To assess the association between drinking pattern and type 2 diabetes, we examined the joint association of the weekly frequency and the quantity per drinking day with type 2 diabetes. Men who consumed 0.1-2.0 or 2.1-4.0 US standard drinks per drinking day on 4-7 days weekly had a lower risk of type 2 diabetes (HR 0.74, 95% CI 0.58 to 0.95; HR 0.74, 95% CI 0.60 to 0.91, respectively) compared to non-drinkers.

CONCLUSIONS

More frequent alcohol consumption lowered the risk of type 2 diabetes. Light to moderate alcohol consumption per drinking day on 4-7 days weekly lowered the risk of type 2 diabetes compared to non-drinkers.

Combined measurement of fasting plasma glucose and A1C is effective for the prediction of type 2 diabetes: the Kansai Healthcare Study

OBJECTIVE

We prospectively assessed whether the combined measurements of fasting plasma glucose (FPG) and A1C were effective for predicting type 2 diabetes.

RESEARCH DESIGN AND METHODS

Study participants included 6,736 nondiabetic Japanese men aged 40-55 years. Type 2 diabetes was diagnosed in those who had an FPG >or=126 mg/dl or who were being treated with an oral antidiabetic agent or insulin. The models including FPG, A1C, and both were compared using the area under the receiver operating characteristic (AUROC) curves.

RESULTS

During the 4-year follow-up period, we confirmed 659 diabetes cases. In multivariate analysis, both FPG and A1C were independently associated with the risk of type 2 diabetes. The model including both FPG and A1C had a greater AUROC curve than that including FPG alone (0.853 vs. 0.818; P < 0.001) or A1C alone (0.853 vs. 0.771; P < 0.001).

CONCLUSIONS

The combined measurement of FPG and A1C was effective for predicting type 2 diabetes.

Lower serum creatinine is a new risk factor of type 2 diabetes: the Kansai healthcare study

OBJECTIVE

Because skeletal muscle is one of the target tissues for insulin, skeletal muscle mass might be associated with type 2 diabetes. Serum creatinine is a possible surrogate marker of skeletal muscle mass. The purpose of this study was to determine whether serum creatinine level is associated with type 2 diabetes.

RESEARCH DESIGN AND METHODS

The study participants were nondiabetic Japanese men (n = 8,570) aged 40-55 years at entry. Type 2 diabetes was diagnosed if fasting plasma glucose was >or=126 mg/dl or if participants were taking oral hypoglycemic medication or insulin.

RESULTS

During the 4-year follow-up period, 877 men developed type 2 diabetes. Lower serum creatinine was associated with an increased risk of type 2 diabetes. The multiple-adjusted odds ratio for those who had serum creatinine levels between 0.40 and 0.60 mg/dl was 1.91 (95% CI 1.44-2.54) compared with those who had levels between 0.71 and 0.80 mg/dl.

CONCLUSIONS

Lower serum creatinine increased the risk of type 2 diabetes.

Liver enzymes compared with alcohol consumption in predicting the risk of type 2 diabetes: the Kansai Healthcare Study

OBJECTIVE

It has been reported that moderate alcohol consumption decreased the risk of type 2 diabetes but that elevated liver enzymes increased it. The comparative importance of alcohol consumption and liver enzymes as predictors of type 2 diabetes remains unconfirmed.

RESEARCH DESIGN AND METHODS

The participants included 8,576 Japanese men, aged 40-55 years, without type 2 diabetes at entry. Type 2 diabetes was diagnosed if a fasting plasma glucose level was >or=126 mg/dl or if participants were taking oral hypoglycemic medications or insulin.

RESULTS

During the 4-year follow-up period, we confirmed 878 cases. In multivariate models, moderate daily alcohol consumption (16.4-42.6 g ethanol/day) decreased the risk of type 2 diabetes, and higher levels of gamma-glutamyltransferase (GGT) and alanine aminotransferase (ALT) increased the risk. In joint analyses of alcohol consumption and liver enzymes, moderate drinkers with the lowest tertile of GGT had the lowest risk of type 2 diabetes. Compared with them, nondrinkers with the highest GGT had the highest risk of type 2 diabetes (odds ratio 3.18 [95% CI 1.75-5.76]). At every level of GGT, moderate or heavy alcohol drinkers (>or=42.7 g ethanol/day) had a lower risk of type 2 diabetes than nondrinkers. The relationship of ALT and daily alcohol consumption with the risk of type 2 diabetes was almost the same as that of GGT.

CONCLUSIONS

GGT, ALT, and daily alcohol consumption were independently associated with the risk of type 2 diabetes. Nondrinkers with the highest GGT or ALT had a high risk of type 2 diabetes.

Effectiveness of arsenic mitigation program in Bangladesh--relationship between arsenic concentrations in well water and urine

BACKGROUND

Arsenic in drinking water remains a major public problem in Bangladesh, although arsenic mitigation programs began there a decade ago. The purpose of this study was to examine the effectiveness of this program by determining the relationship between current arsenic levels in well water and the high level of urinary arsenic excretion.

METHODS

A community-based cross-sectional study was conducted in the Pabna district of Bangladesh between May and July 2005. We included 174 married couples and collected their drinking water from 138 wells. The allowable limit for arsenic in drinking water is 50 microg/L in Bangladesh, while the normal level of urinary arsenic is < or =40 microg x 1.5 L(-1) x day(-1) by Dhaka Community Hospital.

RESULTS

Of 348 subjects, 304 exceeded the urinary arsenic level of 40 microg x 1.5 L(-1) x day(-1). Of all wells, 44.2% had arsenic levels >50 microg/L. Multiple-adjusted odds ratios of urinary arsenic level >40 microg x 1.5 L(-1) x day(-1) were 8.90 (95% CI: 3.31-23.93) for the arsenic level in well water of 11-50 microg/L, and 53.07 (11.91-236.46) for that of 51-332 microg/L, compared with < or =10 microg/L. When the Bangladeshi standard arsenic level in drinking water of 50 microg/L was used, the sensitivity in detecting subjects with a urinary arsenic level >40 microg x 1.5 L(-1) x day(-1) was 50%, although when the World Health Organization (WHO) guideline value of 10 microg/L was used, it was 76.3%.

CONCLUSIONS

Green marked wells, which the Bangladesh government regards as safe, are not always safe. The mitigation programs should use the WHO guideline arsenic level to determine the safety of well water for drinking.