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Toshihide Oizumi

Publications and source records attributed to Toshihide Oizumi.

13 recordsLinked to original sources

Is the measurement of glycated hemoglobin A1c alone an efficient screening test for undiagnosed diabetes? Japan National Diabetes Survey.

The aim of the study was to assess the screening test properties of HbA1c for undiagnosed diabetes (DM) according to the 1999-WHO criteria and its relevance of the Japan National Diabetes Survey Cut-off points for possible and probable DM: HbA1c >or=5.6 and 6.1%. Screening properties of HbA1c predicting undiagnosed DM was examined and compared with that of fasting plasma glucose (FPG) in 1904 Funagata-town inhabitants aged 35-89 years old. The prevalence of previous DM, undiagnosed DM, and impaired glucose regulation (IGR) were 5.5, 6.0, and 18.6%, while the prevalence of probable and possible DM were 7.7 and 5.4%. The area under the receiver operating characteristic curve for undiagnosed DM was similar between HbA1c (0.856 [95% CI: 0.812-0.899]) and FPG (0.902 [0.869-0.936]). HbA1c of 5.6% gave a sensitivity of 56.5%, a specificity of 95.1%, positive and negative predictive values of 44.2 and 97.0%, and a proportion of people above the cut-off point of 8.2%. True positive tests were significantly higher with mean levels of BMI, fasting, and 2-h plasma glucose, and HbA1c, but lower with mean levels of high-density-lipoprotein cholesterol than in false negative tests. The measurement of HbA1c alone may be efficient to screen undiagnosed DM and the cut-off point of 5.6% might be proper with respect to screening tests properties for undiagnosed DM, and prediction of vascular complications in Japan.

Adult↗

Correlation between change in body weight rather than current body weight and change in serum adiponectin levels in a Japanese population -- the Funagata study.

Serum adiponectin levels are decreased in obese subjects. We examined the association of current body weight (BW) and its change with a change in serum adiponectin levels. Serum adiponectin levels at the baseline (from 1995 to 1997) and the 5-year follow-up (from 2000 to 2002) examinations were evaluated in 1003 (M/F, 425/578; age at the baseline examinations, 58.3 +/- 11.7/57.5 +/- 11.0 years) Japanese subjects from a cohort population (N = 2013) of the Funagata study. Correlations and associations of BW at the baseline examinations and changes in BW between the baseline and the follow-up examinations (deltaBW) with changes in the serum adiponectin levels in the study period (deltaAdiponectin) were examined. Stepwise regression analyses revealed a significant correlation of the deltaBW (r = -0.233 and -0.204 for men and women, respectively; r = -0.324 for the upper tertile group divided based on their body mass index in women) with the deltaAdiponectin. However, the BW at the baseline examinations was not significantly correlated in both sexes. Multiple logistic regression analyses revealed that subjects who reduced their BW by 2 kg or more were 2.56 (95% confidence interval, 1.21-5.42; P = .014) and 8.24 times (95% confidence interval, 3.59-18.9; P < .001) more likely to be in the upper tertile of the deltaAdiponectin than those who increased their BW by 2 kg or more in men and women, respectively, independent of their BW at the baseline examinations. In conclusion, we showed here that the deltaBW was strongly associated with the deltaAdiponectin in both sexes, whereas the BW at the baseline examinations was not associated with the deltaAdiponectin, at least in women.

Adiponectin↗

Cardiovascular risk factors and retinal microvascular signs in an adult Japanese population: the Funagata Study.

OBJECTIVE: To describe the prevalence of retinal vascular signs and their association with cardiovascular risk factors in a Japanese population. DESIGN: Population-based cross-sectional study. PARTICIPANTS: Adult persons aged 35 years or older from Funagata, Yamagata Prefecture, Japan (n = 1481). METHODS: The Funagata Study is a Japanese population-based study of persons aged 35 years or older, and included 1961 nondiabetic participants (53.3% of 3676 eligible subjects). A nonmydriatic retinal photograph was taken of 1 eye to assess retinal microvascular signs. Retinal arteriolar wall signs (focal arteriolar narrowing, arteriovenous nicking, enhanced arteriolar wall reflex) and retinopathy were assessed in 1481 participants without diabetes (40.3% of eligible persons) using a standardized protocol. Using a computer-assisted method, retinal vessel diameters were measured in 921 participants with gradable retinal image (25.1% of eligible persons). MAIN OUTCOME MEASURES: Prevalence of retinal microvascular signs and their association with cardiovascular risk factors. RESULTS: Moderate or severe focal arteriolar narrowing, arteriovenous nicking, enhanced arteriolar wall reflex, and retinopathy were found in 8.3%, 15.2%, 18.7%, and 9.0%, respectively, of the study population. Mean (+/-standard error) values for retinal arteriolar diameter were 178.6+/-21.0 mum, and mean values (+/-standard error) for venular diameter were 214.9+/-20.6 mum. Older persons were more likely to have retinal arteriolar wall signs, retinopathy, and narrower retinal vessel diameters. After adjusting for multiple factors, each 10-mmHg increase in mean arterial blood pressure was associated with a 20% to 40% increased likelihood of retinal arteriolar signs and a 2.8-mum reduction in arteriolar diameter. Retinopathy was associated with higher body mass index and both impaired glucose tolerance and impaired fasting glucose. CONCLUSIONS: In nondiabetic Japanese adults, retinal arteriolar wall signs were associated with older age and increased blood pressure, whereas retinopathy was associated with older age, higher body mass index, impaired glucose tolerance, and impaired fasting glucose. These findings are comparable with data from white populations.

Adult↗

Association of the ABCA1 gene polymorphisms with type 2 DM in a Japanese population.

To examine the association of the ATP-binding cassette transporter 1 (ABCA1) gene with type 2 diabetes (DM), we studied genetic polymorphisms of the ABCA1 gene including its linkage disequilibrium (LD) and haplotype analyses using a Japanese population. A sample set (DM:72, IGT:75, and NGT:227) was genotyped with 34 SNPs distributed from the promoter region to the last exon of the ABCA1 gene. LD between SNPs was assessed in pairwise manner. Among 13 LD blocks constructed, an LD block at the 5'-region showed a significant difference in the haplotype distribution between the study groups (NGT vs. IGT + DM: overall p = 0.0180; NGT vs. DM: 0.0001). Fisher's exact probability test (NGT vs. DM) showed a significant association of the haplotype 2 of the LD block (p = 0.0001), with an odds ratio (OR) of 2.53 (95%CI:1.62-4.12). Diplotype analysis also showed a significant association of the diplotypes with the haplotype 2 (OR:2.59, 95%CI:1.48-4.54, p = 0.0013).

ATP Binding Cassette Transporter 1↗

Association of decrease in serum dehydroepiandrosterone sulfate levels with the progression to type 2 diabetes in men of a Japanese population: the Funagata Study.

Association of serum dehydroepiandrosterone sulfate (DHEAS) levels with insulin resistance and impairment of insulin secretion have been reported. We here examined the association of serum DHEAS levels with type 2 diabetes mellitus (DM) and the progression to DM. The serum DHEAS levels at baseline (from 1995 to 1997) were evaluated in 1709 individuals (998 women and 711 men) from a cohort population (n = 3706) of the Funagata Study. Glucose tolerance was evaluated at baseline as well as at 5-year follow-up examinations (n = 970, follow-up rate, 56.8%) according to the 1985 World Health Organization criteria. The statistical significance of the difference between any 2 groups was determined by the Student t test. Multiple logistic regression analysis determined the association of the traits with the progression to DM at the 5-year follow-up examinations. P < .05 was accepted as statistically significant. The serum DHEAS levels were significantly lower in DM than in normal glucose tolerance. However, this difference was not significant when adjusted for age. In men, the decrease in serum DHEAS levels by the 5-year follow-up examinations was significantly larger in the subjects who became diabetic than in the subjects who remained normal glucose tolerance, even when adjusted for age ( P = .0003). Multiple logistic regression analysis revealed a significant association of the decrease in serum DHEAS levels with the progression to DM, with an odds ratio (per 0.1 log ng/mL) of 1.410 (95% confidence interval [CI], 1.020-1.948, P = .038), independently from age, height, and 2-hour plasma glucose in men. A decrease in serum DHEAS levels seems to be associated with the progression to DM in Japanese men.

Aged↗

Large-scale search of SNPs for type 2 DM susceptibility genes in a Japanese population.

The etiology of type 2 diabetes (DM) is polygenic. We investigated here genes and polymorphisms that associate with DM in the Japanese population. Single-nucleotide polymorphisms (SNPs) of 398 derived from 120 candidate genes were examined for association with DM in a population-based case-control study. The study group consisted of 148 cases and 227 controls recruited from Funagata, Japan. No evident subpopulation structure was detected for the tested population. The association tests were conducted with standard allele positivity tables (chi(2) tests) between SNP genotype frequency and case-control status. The independent association of the SNPs from serum triglyceride levels and body mass index was examined by multiple logistic regression analysis. A value of P<0.01 was accepted as statistically significant. Six genes (met proto-oncogene, ATP-binding cassette transporter A1, fatty acid binding protein 2, LDL receptor defect C complementing, aldolase B, and sulfonylurea receptor) were shown to be associated with DM.

ATP-Binding Cassette Transporters↗

The D allele of the angiotensin-converting enzyme insertion/ deletion (I/D) polymorphism is a risk factor for type 2 diabetes in a population-based Japanese sample.

The association of the ACE gene I/D polymorphism with type 2 diabetes (DM) was examined in a population-based Japanese sample. A total of 902 individuals (490 females and 412 males, age 58.8 +/- 12.2 yr) from a cohort population (n = 3,706) of the Funagata diabetes study were divided into three groups according to genotype: D/D (n = 104), I/D (n = 436) and I/I (n = 362). Chi-square test and ANOVA were used for association studies and to assess the differences in the traits' values, respectively. More individuals with the genotypes D/D and I/D were diabetic (8.7% and 4.1%, respectively) than those with the genotype I/I (2.8%, p = 0.008 and p = 0.032, respectively). The genotype D/D was a risk factor for DM (relative risk (RR) 3.13, 95% CI 1.31-7.51), and also for DM and IGT (RR 1.78, 95% CI 14-2.76). Multiple logistic regression analysis also showed that the genotypes with the D allele were risk factors for DM and IGT even when adjusting for age, sex, hypertension and serum total cholesterol levels (odds ratio 1.49, 95% CI 1.01-2.21). The D allele of the ACE gene I/D polymorphism is a risk factor for DM.

Aged↗

Increased urinary levels of pentosidine, pyrraline and acrolein adduct in type 2 diabetes.

This study investigates whether urinary levels of pentosidine, pyrraline and acrolein adduct are increased in type 2 diabetes (DM), and whether these levels are correlated with glycemic control and clinical traits. Urinary levels of pentosidine, pyrraline and acrolein adduct in DM patients (n = 100) recruited from the outpatient clinic of our university hospital were compared with those of age- and sex-matched non-diabetic subjects (n = 50). The correlation of these urinary levels with the glycemic control and the clinical traits were examined. Furthermore, the influence of smoking habit on the levels of acrolein adduct was examined. Urinary levels of pentosidine, pyrraline and acrolein adduct were all significantly (p<0.001) higher in the DM group than in the non-DM group (pentosidine (log(pmol/mgCr)), 1.579 +/- 0.147 vs 1.427 +/- 0.142; pyrraline (log(nmol/mgCr)), 0.888 +/- 0.402 vs 0.581 +/- 0.336; acrolein adduct (log(nmol/mgCr)), 2.316 +/- 0.221 vs 2.051 +/- 0.201). Glycemic control parameters, such as fasting plasma glucose (FPG) and HbA1c, were significantly correlated with these urinary levels. Age was correlated with the urinary levels of pentosidine but not with those of pyrraline and acrolein adduct. The urinary albumin excretion rate did not correlate with any of these urinary levels. The levels of acrolein adduct were higher in the subjects with smoking habit than in those without the habit in the DM group as well as in the non-DM group (DM, 2.391 +/- 0.230 and 2.212 +/- 0.190, p=0.0004; Non-DM, 2.120 +/- 0.171 and 1.993 +/- 0.206, p=0.0503). The urinary levels of pentosidine, pyrraline and acrolein adduct were increased in DM and were significantly correlated with glycemic control levels. In addition, smoking habit seems to increase the urinary levels of acrolein adduct.

Acrolein↗

Decreased serum levels of adiponectin are a risk factor for the progression to type 2 diabetes in the Japanese Population: the Funagata study.

OBJECTIVE: To examine whether decreased serum levels of adiponectin are an independent risk factor for the progression to type 2 diabetes in a Japanese population. RESEARCH DESIGN AND METHODS: The serum levels of adiponectin and tumor necrosis factor-alpha (TNF-alpha) at baseline (from 1995 to 1997) were evaluated in 1,792 individuals (1,023 women and 769 men, aged 58.5 +/- 12.5 years) from a cohort population (n = 3,706) of the Funagata study. Glucose tolerance was evaluated at baseline and also at 5-year follow-up examinations (n = 978, follow-up rate, 54.6%) according to the 1985 World Health Organization criteria. The correlation of clinical traits with serum levels of adiponectin was examined. The association of the traits with the progression to type 2 diabetes at the 5-year follow-up was also examined. RESULTS: Among the traits examined, the correlation with aging was highest (r = 0.312, P < 0.001). Eighteen subjects with normal glucose tolerance (NGT) developed diabetes, and 709 remained NGT at the 5-year follow-up examinations. The subjects who became diabetic had decreased serum levels of adiponectin (7.29 +/- 2.35 vs. 9.13 +/- 2.35 10 x log microg/ml, P = 0.009). Multiple logistic regression analysis with age, sex, waist-to-hip ratio, and 2-h plasma glucose as the variables revealed that serum adiponectin level (odds ratio [per 0.1 log microg/ml] 0.766, P = 0.029) was an independent risk factor for the progression to type 2 diabetes. The subjects whose serum levels of adiponectin were in the lowest tertile were 9.320 times (95% CI 1.046-83.1) more likely to develop diabetes than those in the highest tertile (P = 0.046). CONCLUSIONS: Decreased serum adiponectin level is an independent risk factor for progression to type 2 diabetes.

Adiponectin↗

Calpain 10 gene polymorphisms are related, not to type 2 diabetes, but to increased serum cholesterol in Japanese.

A G-to-A (UCSNP-43) polymorphism of the calpain-10 gene was significantly associated with type 2 diabetes (DM) in Mexican-American, and was postulated, together with a T-to-C (UCSNP-44) polymorphism, as a risk factor for DM. We examined the association of these genotypes with DM in Japanese. Eighty-one subjects with DM and 81 non-diabetic subjects (NGT) were recruited. The number of subjects with genotypes UCSNP-43 G/G, G/A and A/A were 76, 5 and 0, respectively, for the DM and NGT groups. The number of subjects with genotypes UCSNP-44 T/T, T/C and C/C were 66, 14 and 1 for the DM group and 64, 17 and 0 for the NGT group. There was no difference between the groups in terms of frequency of any genotype combinations. No association between the genotypes and DM was observed. We next examined the differences between the genotypes or genotype combinations in terms of the traits related to DM, obesity, hypertension and dyslipidemia. No differences were observed between the genotypes UCSNP43 G/G and G/A, between UCSNP-44 T/T and the others, or between the genotype combination UCSNP-43 G/G and UCSNP-44 T/T and the others, except that the individuals with the genotype combination had significantly increased serum cholesterol levels (212.6 +/- 34.3 vs. 198.5 +/- 29.9, P=0.020). The genotype combination might be a risk factor, not for DM, obesity and hypertension, but for increased serum cholesterol.

Aged↗