Prevalence of diabetes mellitus in Japan compiled from literature

Diagnosed diabetes and premature death among middle-aged Japanese: results from a large-scale population-based cohort study in Japan (JPHC study)

OBJECTIVE

To examine the association between diabetes and premature death for Japanese general people.

DESIGN

Prospective cohort study.

SETTING

The Japan Public Health Center-based prospective study (JPHC study), data collected between 1990 and 2010.

POPULATION

A total of 46,017 men and 53,567 women, aged 40-69 years at the beginning of baseline survey.

MAIN OUTCOME MEASURES

Overall and cause specific mortality. Cox proportional hazards models were used to calculate the HRs of all cause and cause specific mortality associated with diabetes.

RESULTS

The median follow-up period was 17.8 years. During the follow-up period, 8223 men and 4640 women have died. Diabetes was associated with increased risk of death (856 men and 345 women; HR 1.60, (95% CI 1.49 to 1.71) for men and 1.98 (95% CI 1.77 to 2.21) for women). As for the cause of death, diabetes was associated with increased risk of death by circulatory diseases (HR 1.76 (95% CI 1.53 to 2.02) for men and 2.49 (95% CI 2.06 to 3.01) for women) while its association with the risk of cancer death was moderate (HR 1.25 (95% CI 1.11 to 1.42) for men and 1.04 (95% CI 0.82 to 1.32) for women). Diabetes was also associated with increased risk of death for 'non-cancer, non-circulatory system disease' (HR 1.91 (95% CI 1.71 to 2.14) for men and 2.67 (95% CI 2.25 to 3.17) for women).

CONCLUSIONS

Diabetes was associated with increased risk of death, especially the risk of death by circulatory diseases.

Cholesterol and egg intakes and the risk of type 2 diabetes: the Japan Public Health Center-based Prospective Study

Limited and inconsistent associations between cholesterol and egg consumption and type 2 diabetes risk have been observed in Western countries. In the present study, the association of dietary cholesterol and egg intakes with type 2 diabetes risk was examined prospectively. The study subjects comprised 27, 248 men and 36,218 women aged 45-75 years who participated in the second survey of the Japan Public Health Center-based Prospective Study and had no histories of type 2 diabetes or other serious diseases. Dietary cholesterol and egg intakes were estimated using a validated 147-item FFQ. The OR of self-reported, physician-diagnosed type 2 diabetes over 5 years were estimated using multiple logistic regression. A total of 1165 newly diagnosed cases of type 2 diabetes were self-reported. Although dietary cholesterol intake was not associated with type 2 diabetes risk in men, it was found to be associated with a 23 % lower odds of type 2 diabetes risk in women in the highest quartile of intake, albeit not statistically significant, compared with those in the lowest quartile (P trend= 0·08). Such risk reduction was somewhat greater among postmenopausal women; the multivariable-adjusted OR for the highest quartile of cholesterol intake compared with the lowest quartile was 0·68 (95 % CI 0·49, 0·94; P trend= 0·04). No association between egg intake and type 2 diabetes risk was found in either men or women. In conclusion, higher intake of cholesterol or eggs may not be associated with an increased risk of type 2 diabetes in Japanese populations. The observed association between decreased type 2 diabetes risk and higher dietary cholesterol intake in postmenopausal women warrants further investigation.

Efficiency of a free-living physical activity promotion program following diet modification for fat loss in Japanese obese men

The aim of the current study was to examine the efficiency of a free-living physical activity promotion (PAP) program following a diet modification program for fat loss. Fifty obese men, aged 51.4±7.0 y, received a 6-mo regimen consisting of 2 phases. Weekly 90-min free-living PAP sessions were provided for 3 mo immediately after a 3-mo diet modification phase. Fat mass (FM) was measured at baseline and at months 3 and 6 using dual energy X-ray absorptiometry. The time spent in moderate-vigorous physical activity (MVPA) was monitored by a validated single-axis accelerometer. The total energy intake of all participants was assessed at baseline and during weeks 9 and 10 of both the diet modification and PAP programs. The change (Δ) in FM was -1.4±1.9 kg (p<0.05) during the PAP program after the diet modification program (-4.3±2.9 kg, p<0.01). Although there was no significant relationship between ΔFM and ΔMVPA during the PAP phase (p=0.11), MVPA was significantly increased during the PAP phase (+76.0±146.5 min/wk, p<0.01). However, a significant correlation was observed between energy intake/weight and MVPA during the PAP program (r=0.39). Our results suggest that the magnitude of expected FM loss induced by an increase in PA may be suppressed as a result of increased energy intake, even during a PAP program after a diet modification program.

Air displacement plethysmography for estimating body composition changes with weight loss in middle-aged Japanese men

AIM

To examine the degree to which air displacement plethysmography (ADP) can track body composition changes in response to weight loss in obese Japanese men.

METHOD

50 men, aged 30-65 years with a mean BMI of 30 kg/m(2), were included in a 3-month weight loss program. Percentage of fat mass (%FM) was determined by dual energy X-ray absorptiometry (DXA) and ADP at baseline and month 3.

RESULTS

With 6.2 ± 4.3 kg of weight loss, %FM, as determined by DXA and ADP, significantly decreased by 3.9 ± 2.9% and 3.9 ± 3.3% respectively. There was no mean difference for change (Δ) in %FM between the two methods. DXA-derived Δ%FM significantly correlated with Δ%FM determined by ADP (R(2) = 0.48, p < 0.01). Furthermore, the Bland-Altman plots demonstrated no systematic bias for Δ%FM (r = -0.20, p = 0.17). However, %FM by ADP (r = 0.42) at baseline and Δ%FM by ADP (r = -0.54) were significantly correlated to the differences between Δ%FM by DXA and ADP.

CONCLUSION

These results suggest that ADP is comparably accurate for evaluating Δ%FM when compared with DXA, although there were proportional biases.

A plant-based diet for type 2 diabetes: scientific support and practical strategies

PURPOSE

The purpose of this review is to provide educators with the knowledge and tools to utilize plant-based nutrition education as an intervention for type 2 diabetes. Scientific support for the efficacy, acceptability, and nutritional adequacy of a plant-based diet for people with type 2 diabetes is presented, and practical considerations such as medication adjustment and risk of hypoglycemia are reviewed.

CONCLUSIONS

Plant-based meal planning is an acceptable and effective strategy that educators can use to improve diabetes management and reduce risk of complications. Studies show that dietary changes that are effective for reducing cardiac risk may also be helpful for management of type 2 diabetes. A low-fat, plant-based diet reduces body weight and improves glycemic control, and has been shown to be remarkably well accepted by patients.

Usefulness of vegetarian and vegan diets for treating type 2 diabetes

Significant benefits for diabetes prevention and management have been observed with vegetarian and especially vegan diets. This article reviews observational studies and intervention trials on such diets, and discusses their efficacy, nutritional adequacy, acceptability, and sustainability. Research to date has demonstrated that a low-fat, plant-based nutritional approach improves control of weight, glycemia, and cardiovascular risk. These studies have also shown that carefully planned vegan diets can be more nutritious than diets based on more conventional diet guidelines, with an acceptability that is comparable with that of other therapeutic regimens. Current intervention guidelines from professional organizations offer support for this approach. Vegetarian and vegan diets present potential advantages in managing type 2 diabetes that merit the attention of individuals with diabetes and their caregivers.

The effects of vigorous physical activity on intra-abdominal fat levels: a preliminary study of middle-aged Japanese men

AIM

To examine the effects of vigorous physical activity (PA) on intra-abdominal fat (IF) levels in obese men.

METHODS

Thirty-seven obese men (mean age: 47.6+/-8.6 years) engaged in a 12-week aerobic exercise program on a regular basis (3 days/week). We divided them into low volume of vigorous PA group (n=19) or high volume of vigorous PA group (n=18), based on the median time spent (34.3min/week) in vigorous PA (over 6.1 metabolic equivalents assessed by a single-axis accelerometer) throughout the program.

RESULTS

Regular exercise reduced IF levels (measured by computed tomography) from 188.1+/-53.9cm(2) to 170.3+/-46.6cm(2) for the low volume of vigorous PA group and from 167.9+/-44.3cm(2) to 137.9+/-40.6cm(2) for the high volume of vigorous PA group. Two-way (time x group) ANOVA revealed no significant interactions for the IF level. However, correlation analysis for all participants showed that time spent in vigorous PA throughout the program significantly correlated to IF reductions after adjusting for initial levels of IF, vigorous PA and weight changes (r=-0.42, P=0.02).

CONCLUSION

This study suggests that vigorous PA may affect IF reductions in obese men.

PPARG genotype accounts for part of individual variation in body weight reduction in response to calorie restriction

Several studies indicate that expression of the peroxisome proliferator-activated receptor gamma (PPARG) gene is influenced by calorie restriction. The aim of this study was to investigate whether PPARG gene variations are associated with weight reduction and changes in coronary heart disease (CHD) risk factors in response to a 14-week calorie restriction. In total, 95 middle-aged, Japanese women (BMI>or=25 kg/m2) enrolled as subjects for 14 weeks and attended weekly dietary lectures instructing them on how to consume a nutritionally balanced diet of 1,200 kcal/day. Eight single-nucleotide polymorphisms (SNPs) in the PPARG gene (rs1801282 (Pro/Ala), rs2292101, rs2959272, rs1386835, rs709158, rs1175540, rs1175544, and rs1797912) were analyzed. Body weight decreased significantly (-7.7+/-3.1 kg; -11.3+/-4.4%) during the intervention. Six PPARG SNPs (rs2959272, rs1386835, rs709158, rs1175540, rs1175544, and rs1797912) were significantly associated with the weight reduction, with rs1175544 having the strongest association (P=0.004). No differences across the rs1175544 genotypes were observed in any of the blood analyses or in blood pressure. In a multiple regression analysis, the rs1175544 genotypes accounted for 7% of the total weight reduction variance. These data suggest that one SNP of the PPARG genotype accounted for a significant portion of the total body weight reduction variance in response to a short-term intervention consisting of calorie restriction; however, no relationship was found between these SNPs and the changes in CHD risk factors which accompanied weight loss.

Obesity phenotype and intra-abdominal fat responses to regular aerobic exercise

AIM

To examine the effects of obesity phenotype on abdominal fat responses to regular aerobic exercise.

METHOD

Fifty-seven obese men aged 34-70 years were divided into two groups based on baseline intra-abdominal fat (IF) area measured by computerized tomography: moderate (<200 cm(2)) IF (MIF; n=33, age: 52.9+/-10.6 [SD] yr, body mass index [BMI]: 29.2+/-3.1 kg/m(2)) or high (>or=200 cm(2)) IF (HIF; n=24, age: 53.5+/-9.5 yr, BMI: 30.3+/-3.1 kg/m(2)). The 12-week exercise program consisted primarily of aerobic exercise and met 3 days per week for 90 min per session. Weight, BMI, body composition (by dual-energy X-ray absorptiometry), IF and subcutaneous fat (SF) areas were measured before and after the program.

RESULTS

Regular aerobic exercise reduced weight by 2.3+/-2.2 kg in MIF and 3.2+/-3.0 kg in HIF. HIF reduced significantly more IF area than MIF (15.1+/-26.0 cm(2) in MIF and 43.3+/-41.9 cm(2) in HIF), and the difference remained significant after adjusting for baseline fat mass, weight change and total energy intake during the 12-week aerobic exercise.

CONCLUSION

Exercise-induced IF reduction may be remarkably influenced by obesity phenotype.

Association between TCF7L2 gene polymorphisms and susceptibility to type 2 diabetes mellitus: a large Human Genome Epidemiology (HuGE) review and meta-analysis

BACKGROUND

Transcription factor 7-like 2 (TCF7L2) has been shown to be associated with type 2 diabetes mellitus (T2MD) in multiple ethnic groups in the past two years, but, contradictory results were reported for Chinese and Pima Indian populations. The authors then performed a large meta-analysis of 36 studies examining the association of type 2 diabetes mellitus (T2DM) with polymorphisms in the TCF7L2 gene in various ethnicities, containing rs7903146 C-to-T (IVS3C>T), rs7901695 T-to-C (IVS3T>C), a rs12255372 G-to-T (IVS4G>T), and rs11196205 G-to-C (IVS4G>C) polymorphisms and to evaluate the size of gene effect and the possible genetic mode of action.

METHODS

Literature-based searching was conducted to collect data and three methods, that is, fixed-effects, random-effects and Bayesian multivariate mete-analysis, were performed to pool the odds ratio (OR). Publication bias and study-between heterogeneity were also examined.

RESULTS

The studies included 35,843 cases of T2DM and 39,123 controls, using mainly primary data. For T2DM and IVS3C>T polymorphism, the Bayesian OR for TT homozygotes and TC heterozygotes versus CC homozygote was 1.968 (95% credible interval (CrI): 1.790, 2.157), 1.406 (95% CrI: 1.341, 1.476), respectively, and the population attributable risk (PAR) for the TT/TC genotypes of this variant is 16.9% for overall. For T2DM and IVS4G>T polymorphism, TT homozygotes and TG heterozygotes versus GG homozygote was 1.885 (95%CrI: 1.698, 2.088), 1.360 (95% CrI: 1.291, 1.433), respectively. Four ORs among these two polymorphisms all yielded significant between-study heterogeneity (P < 0.05) and the main source of heterogeneity was ethnic differences. Data also showed significant associations between T2DM and the other two polymorphisms, but with low heterogeneity (P > 0.10). Pooled ORs fit a codominant, multiplicative genetic model for all the four polymorphisms of TCF7L2 gene, and this model was also confirmed in different ethnic populations when stratification of IVS3C>T and IVS4G>T polymorphisms except for Africans, where a dominant, additive genetic mode is suggested for IVS3C>T polymorphism.

CONCLUSION

This meta-analysis demonstrates that four variants of TCF7L2 gene are all associated with T2DM, and indicates a multiplicative genetic model for all the four polymorphisms, as well as suggests the TCF7L2 gene involved in near 1/5 of all T2MD. Potential gene-gene and gene-environmental interactions by which common variants in the TCF7L2 gene influence the risk of T2MD need further exploration.

Association between TCF7L2 gene polymorphisms and susceptibility to type 2 diabetes mellitus: a large Human Genome Epidemiology (HuGE) review and meta-analysis

Background

Transcription factor 7-like 2 (TCF7L2) has been shown to be associated with type 2 diabetes mellitus (T2MD) in multiple ethnic groups in the past two years, but, contradictory results were reported for Chinese and Pima Indian populations. The authors then performed a large meta-analysis of 36 studies examining the association of type 2 diabetes mellitus (T2DM) with polymorphisms in the TCF7L2 gene in various ethnicities, containing rs7903146 C-to-T (IVS3C>T), rs7901695 T-to-C (IVS3T>C), a rs12255372 G-to-T (IVS4G>T), and rs11196205 G-to-C (IVS4G>C) polymorphisms and to evaluate the size of gene effect and the possible genetic mode of action.

Methods

Literature-based searching was conducted to collect data and three methods, that is, fixed-effects, random-effects and Bayesian multivariate mete-analysis, were performed to pool the odds ratio (OR). Publication bias and study-between heterogeneity were also examined.

Results

The studies included 35,843 cases of T2DM and 39,123 controls, using mainly primary data. For T2DM and IVS3C>T polymorphism, the Bayesian OR for TT homozygotes and TC heterozygotes versus CC homozygote was 1.968 (95% credible interval (CrI): 1.790, 2.157), 1.406 (95% CrI: 1.341, 1.476), respectively, and the population attributable risk (PAR) for the TT/TC genotypes of this variant is 16.9% for overall. For T2DM and IVS4G>T polymorphism, TT homozygotes and TG heterozygotes versus GG homozygote was 1.885 (95%CrI: 1.698, 2.088), 1.360 (95% CrI: 1.291, 1.433), respectively. Four ORs among these two polymorphisms all yielded significant between-study heterogeneity (P < 0.05) and the main source of heterogeneity was ethnic differences. Data also showed significant associations between T2DM and the other two polymorphisms, but with low heterogeneity (P > 0.10). Pooled ORs fit a codominant, multiplicative genetic model for all the four polymorphisms of TCF7L2 gene, and this model was also confirmed in different ethnic populations when stratification of IVS3C>T and IVS4G>T polymorphisms except for Africans, where a dominant, additive genetic mode is suggested for IVS3C>T polymorphism.

Conclusion

This meta-analysis demonstrates that four variants of TCF7L2 gene are all associated with T2DM, and indicates a multiplicative genetic model for all the four polymorphisms, as well as suggests the TCF7L2 gene involved in near 1/5 of all T2MD. Potential gene-gene and gene-environmental interactions by which common variants in the TCF7L2 gene influence the risk of T2MD need further exploration.

An update on the etiology and epidemiology of diabetes mellitus

Diabetes mellitus is one of the most common endocrine disorders affecting almost 6% of the world's population. The number of diabetic patients will reach 300 million in 2025 (International Diabetes Federation, 2001). More than 97% of these patients will have type II diabetes. The projected increase in the number of diabetic patients will strain the capabilities of healthcare providers the world over. Thus it is of paramount importance to revisit the causes and epidemiology of diabetes mellitus. Diabetes mellitus is caused by both environmental and genetic factors. The environmental factors that may lead to the development of diabetes mellitus include physical inactivity, drugs and toxic agents, obesity, viral infection, and location. While type I diabetes is not a genetically predestined disease, an increased susceptibility can be inherited. Genetic susceptibility plays a crucial role in the etiology and manifestation of type II diabetes, with concordance in monozygotic twins approaching 100%. Genetic factors may have to be modified by environmental factors for diabetes mellitus to become overt. An individual with a susceptible gene may become diabetic if environmental factors modify the expression of these genes. Since there is an increase in the trend at which diabetes prevail, it is evident that environmental factors are playing a more increasing role in the cause of diabetes mellitus. The incidence of type I diabetes ranged from 1.9 to 7.0/100,000/yr in Africa, 0.13 to 10/100,000/yr in Asia, approximately 4.4/100,000/yr in Australasia, 3.4 to 36/100,000/yr in Europe, 2.62 to 20.18/100,000/yr in the Middle East, 7.61 to 25.7/100,000/yr in North America, and 1.27 to 18/100,000/yr in South America. The epidemiology of type II diabetes is equally bleak. The prevalence of type II diabetes ranged from 0.3 to 17.9% in Africa, 1.2 to 14.6% in Asia, 0.7 to 11.6% in Europe, 4.6 to 40% in the Middle East, 6.69 to 28.2% in North America, and 2.01 to 17.4% in South America.

Differential impact of family history on age-associated increase in the prevalence of hypertension and diabetes in male Japanese workers

Family history and aging are independent risk factors for the development of hypertension as well as for the development of diabetes. However, it is unclear how the family histories influence the rate of age-associated increase in these diseases. Moreover, despite the fact that hypertension and diabetes often occur concomitantly, it is not known whether family history of hypertension increases the risk of diabetes or vice versa. To gain an insight into these questions, we investigated the cross-sectional prevalence and family history of hypertension and diabetes in 1,123 male subjects (mean age, 42.1 +/- 12 years; range, 20-60 years) who participated in annual medical check-ups. The data were analyzed by 10-year age groups (20s, 30s, 40s and 50s). The prevalence of hypertension increased with age group either in the absence (12% in the 20s and 39% in the 50s) or in the presence (21% in the 20s and 59% in the 50s) of family history of hypertension, and thus the increasing rate of prevalence with age was not affected by family history. The prevalence of diabetes in the absence of family history of diabetes was low until the 40s (< 1.2%) but it jumped in the 50s (4.3%). On the other hand, in the presence of family history, the prevalence was 4% in the 20s and progressively increased to 20% in the 50s. The impact of family history on the risk of diabetes was strong and appeared to increase with age. Family history of hypertension did not increase the risk of diabetes, and family history of diabetes did not increase the risk of hypertension. These results suggest that family history of hypertension has an additive impact on the age-associated increase in the risk of hypertension, whereas family history of diabetes has an exponential impact on aging-associated increase in the risk of diabetes.

Prevention of type 2 diabetes by lifestyle intervention: a Japanese trial in IGT males

Prevention of type 2 diabetes by intensive lifestyle intervention designed to achieve and maintain ideal body weight was assessed in subjects with impaired glucose tolerance (IGT). Male subjects with IGT recruited from health-screening examinees were randomly assigned in a 4:1 ratio to a standard intervention group (control group) and intensive intervention group (intervention group). The final numbers of subjects were 356 and 102, respectively. The subjects in the control group and in the intervention group were advised to maintain body mass index (BMI) of <24.0 kg/m2 and of <22.0 kg/m2, respectively, by diet and exercise. In the intervention group, detailed instructions on lifestyle were repeated every 3-4 months during hospital visits. Diabetes was judged to have developed when two or more consecutive fasting plasma glucose (FPG) values exceeded 140 mg/dl. A 100g oral glucose tolerance test was performed every 6 months to detect improvement of glucose tolerance. The subjects were seen in an ordinary outpatient clinic. The cumulative 4-year incidence of diabetes was 9.3% in the control group, versus 3.0% in the intervention group, and the reduction in risk of diabetes was 67.4% (P < 0.001). Body weight decreased by 0.39 kg in the control group and by 2.18 kg in the intervention group (P < 0.001). The control group was subclassified according to increase and decrease in body weight. The incidence of diabetes was positively correlated with the changes in body weight, and the improvement in glucose tolerance was negatively correlated. Subjects with higher FPG at baseline developed diabetes at a higher rate than those with lower FPG. Higher 2h plasma glucose values and higher BMI values at baseline were also associated with a higher incidence of diabetes, but the differences were not significant. Subjects with a low insulinogenic index (DeltaIRI/DeltaPG 30 min after an oral glucose load) developed diabetes at a significantly higher rate than those with a normal insulinogenic index. Comparison of the BMI data and incidence of diabetes in five diabetes prevention studies by lifestyle intervention revealed a linear correlation between the incidence of diabetes and the BMI values, with the exception of the DaQing Study. However, the slope of the reduction in incidence of diabetes in the intensive intervention groups was steeper than expected simply on the basis of the reduction of BMI, suggesting that the effect of lifestyle intervention cannot be solely ascribed to the body weight reduction. We conclude that lifestyle intervention aimed at achieving ideal body weight in men with IGT is effective and can be conducted in an outpatient clinic setting.

Long-period accelerometer monitoring shows the role of physical activity in overweight and obesity

CONTEXT

Physical activity (PA) plays an important role in obesity. A new accelerometer has been developed to assess total energy expenditure as well as PA.

OBJECTIVE

To investigate the association of PA with overweight and obesity in Japanese men and women, a large cross-sectional study was performed using a single-axis accelerometer.

DESIGN, SETTING AND PARTICIPANTS

Population-based cross-sectional study of Japanese 18-84 y of age. Height, body weight and PA were measured in 400 male and 388 female Japanese volunteers from 1999 to 2000. The outcome measurements were overweight and obesity, which are defined as a body mass index >/=25 kg/m(2). PA was measured for 1 to 4 weeks and was then categorized into three activity levels, which were defined as light, moderate and vigorous PA.

RESULTS

Prevalence of overweight and obesity was 22.3%. Number of steps and time spent in moderate and vigorous PA per day were lower in overweight and obese individuals. No difference was found in time spent in light PA. Individuals who are in the 4th and 5th quintile of moderate and vigorous PA showed a significantly lower body mass index. When odd ratios (ORs) of overweight and obesity estimated by logistic regression were used as effect measures, overweight and obesity were negatively associated with vigorous PA (ORs=0.91).

CONCLUSION

These results indicate that overweight and obese individuals have a lower step rate and are spending less time for moderate to vigorous PA. Participation in vigorous PA is an important predictor of overweight and obesity.

Target value of intraabdominal fat area for improving coronary heart disease risk factors

OBJECTIVE

The goal of this study was to determine an intraabdominal fat (IF) area target value for improving coronary heart disease (CHD) risk factors in response to weight reduction.

RESEARCH METHODS AND PROCEDURES

Subjects were 279 obese Japanese women, 21 to 66 years old, who were divided into diet-alone and diet-plus-exercise groups and participated in a 14-week weight reduction program. The IF area was measured by computerized tomography scans. Systolic blood pressure > or = 140 mm Hg, diastolic blood pressure > or = 90 mm Hg, total cholesterol > or = 5.70 mM, triglycerides > or = 1.70 mM, and fasting plasma glucose > or = 6.99 mM were defined as CHD risk factors.

RESULTS

The best trade-off between sensitivity (probability of correctly detecting true positive) and specificity (probability of correctly detecting true negative) was found at 100 cm2 pretreatment in combined data of the two groups. At posttreatment, although a slight difference was found in the target value between the treatment groups (60 cm2 for diet alone and 50 cm2 for diet plus exercise), the combined data showed that the best trade-off occurred at 60 cm2 (sensitivity and specificity were 0.55 and 0.63, respectively). The percentage of subjects having no CHD risk factors was significantly lower in the group that had large IF areas (> or = 60 cm2) (46%) compared with the group that had normal IF areas (<60 cm2) (65%). However, the percentage of subjects having multiple CHD risk factors was significantly greater in the group that had large IF areas (16%) compared with the group with normal IF areas (7%) at posttreatment.

DISCUSSION

Our longitudinal data suggest that obese Japanese women should reduce their IF areas to < 60 cm2 through weight reduction to improve CHD risk factors independent of treatment.

Prevalence of diabetes mellitus in the elderly of Namwon County, South Korea

BACKGROUND

Ethnic and geographic differences exist in the prevalence of diabetes mellitus which has increased dramatically in South Korea. A few community-based epidemiologic studies with oral glucose tolerance test were performed in South Korea. The purpose of this study was to determine the prevalence of diabetes mellitus by the World Health Organization (WHO) and the American Diabetic Association (ADA) diagnostic criteria and to investigate their associated risk factors. Also, we compared and analyzed the characteristics of Koreans by WHO and ADA diagnostic criteria.

METHODS

Between March 22, 1999 and July 14, 1999, a random sampling of 1,445 residents over 40 years of age in five villages (3 myons and 2 dongs) in Namwon City. Chollabuk-do Province, South Korea was carried out. WHO and ADA diagnostic criteria were used for the prevalence of DM, IGT and IFG. The associated factors of subjects were analyzed.

RESULTS

After age adjustment for the population projection of Korea (1999), the prevalence of DM and IGT was 13.7% and 13.8%, respectively, by WHO criteria, while the prevalence of DM, IGT and IFG was 15.8%, 12.8% and 5.7%, respectively, by ADA criteria, and the previous diagnosed diabetics were 5.8% in 665 adults over 40 years of age in the Namwon area. The age-adjusted prevalence of previously diagnosed diabetics was 5.8%. When the subjects classified by both criteria were compared, the level of agreement between WHO and ADA diagnostic criteria, except IFG, was very high (kappa = 0.94; p < 0.001). The ROC curve analysis determined FSG of 114.5 mg/dL (6.4 mmol/L) to yield optimal sensitivity and specificity corresponding to a PP2SG 200 mg/dL (11.1 mmol/L). The prevalence of DM and IGT with ADA diagnostic criteria rose with increasing age (p < 0.05). The body mass index was mean 23.8 +/- 3.4 in all the subjects, 23.75 +/- 3.46 in NGT group and 23.67 +/- 3.16 in DM group, but the differences in the prevalence of DM, IGT and IFG by BMI were not significant. The prevalence of DM rose significantly with the increase in the waist-hip ratio (p < 0.05). The prevalence of DM significantly increased in subjects by increases in blood pressure, and triglyceride and the relative risk in the prevalence of DM was significantly high with dyslipidemia (Odds ratio 2.29, 95% CI: 1.16-3.49).

CONCLUSION

The prevalence of Diabetes Mellitus in the population over 40 years of age in Namwon City. South Korea remarkably increased compared with the 1970s and 1980s and was similar to that of the West. Ethnic differences in obesity of normal, DM and IGT subjects and in the effect on the prevalence of DM may exist in the Korean population, but they were not significant. As there is a limit in number, it is considered that a general population-based epidemiologic study on a large scale is required to investigate ethnic and geographic differences for the risk factors of DM in South Korea. The level of agreement, except IFG, by WHO and ADA diagnostic criteria was high, which indicates that these results may show that not only fasting serum glucose but also postprandial 2-h serum glucose are important for diagnosing diabetes in Korean.

Disturbances of glucose and lipid metabolism in first and second generation Japanese-Brazilians. Japanese-Brazilian Diabetes Study Group

Increased prevalence of self-reported NIDDM in Japanese-Brazilians was reported when compared to Japan. This study aimed at determining the prevalence of NIDDM and IGT in Japanese-Brazilians living in the city of Bauru, São Paulo, Brazil. The impact of western environment on the frequency of obesity, dyslipidemia and hypertension was investigated. All Issei (first generation; n = 238) and a random sample of Nisei (second generation; n = 292), aged 40-79 years, were selected for clinical examination and OGTT (WHO criteria). Age-adjusted prevalence of NIDDM did not differ between men and women for Issei (12.4 vs. 11.6%, respectively), but it became different for Nisei (21.7 vs. 11.4%, P < 0.03) due to an increased rate among men. Increased IGT prevalence was also observed between Issei and Nisei men (8.5 vs. 19.3%, P < 0.03). Issei women had a higher IGT rate than Issei men (27. 3 vs. 8.5%, P < 0.0005). Body mass index (BMI) was higher in the second generation (24.1 +/- 3.6 vs. 23.3 +/- 3.1 kg/m2, P < 0.00005) and also the frequency of obesity, defined as BMI > 25 kg/m2. Comparison of waist/hip ratio by gender showed that only among women, Nisei had lower ratio than Issei (0.90 vs. 0.88, P < 0.05). Nisei had a lower total and LDL-cholesterol than Issei but triglyceride and HDL-cholesterol did not differ. Nisei women (younger than the Issei) had lower triglyceride and total cholesterol. This pattern was not seen between the two generations of men. Considering the mean blood pressure values, Issei and Nisei groups with normal glucose tolerance were not hypertensive. Systolic blood pressure was lower in Nisei and the inverse was found concerning diastolic levels. NIDDM prevalence in Japanese-Brazilians is higher than in Japan and in the general Brazilian population. Besides environment, genetic factors may confer susceptibility to NIDDM when they are exposed to a western environment. Before developing glucose intolerance, disturbances of lipid profile and blood pressure could be detected. Nisei may be more affected due to a longer exposure to an unfavorable environment and these changes seem to occur earlier among men than women.