PREVALENCE OF IMPAIRED GLUCOSE REGULATION IN THE POPULATION OF TIANJIN

Objective To investigate the prevalence of impaired glucose regulation （IGR） in the population of Tianjin. Methods A cross-sectional study was conducted in Tianjin from June to September in 2005. The multi-phasic stratified cluster sampling method was adopted. Totally, 21454 people were selected as survey sample. Information on risk factors was collected through face-to-face questionnaire interview. Fasting capillary whole blood glucose level and other clinical indexes were tested. Results The prevalence of impaired fasting glucose （IFG） in the population was 5.61% （5.32% in male, 5.89% in female）. The prevalence of impaired glucose tolerance （IGT） was 2.91% （2.59% in male, 3.20% in female） in whole population, and the prevalence of female was significantly higher than that of male （P = 0.04）. The prevalences of IFG and IGT increased with the increasing of age. And the prevalences were also influenced by the profession, educational level, and income level. Conclusion The prevalences oflGT and IFG in Tianjin are similar to those in the other big cities of China.

Decreasing complexity of glucose time series derived from continuous glucose monitoring is correlated with deteriorating glucose regulation

Most information used to evaluate diabetic statuses is collected at a special time-point,such as taking fasting plasma glucose test and providing a limited view of individual’s health and disease risk.As a new parameter for continuously evaluating personal clinical statuses,the newly developed technique“continuous glucose monitoring”(CGM)can characterize glucose dynamics.By calculating the complexity of glucose time series index(CGI)with refined composite multi-scale entropy analysis of the CGM data,the study showed for the first time that the complexity of glucose time series in subjects decreased gradually from normal glucose tolerance to impaired glucose regulation and then to type 2 diabetes(P for trend<0.01).Furthermore,CGI was significantly associated with various parameters such as insulin sensitivity/secretion(all P<0.01),and multiple linear stepwise regression showed that the disposition index,which reflectsβ-cell function after adjusting for insulin sensitivity,was the only independent factor correlated with CGI(P<0.01).Our findings indicate that the CGI derived from the CGM data may serve as a novel marker to evaluate glucose homeostasis.

Glycated Haemoglobin in Diagnosis of Diabetes Mellitus and Pre-diabetes among Middle-aged and Elderly Population:Shanghai Changfeng Study

Objective To investigate the optimal glycated haemoglobin （HbAlc） cut off points and evaluate the impact of HbAlc on diabetes and pre-diabetes in middle-aged and elderly population. Methods Subjects were recruited from Shanghai Changfeng Study. A total of 1 973 community-based participants （age_〉45） without known diabetes underwent oral glucose tolerance test （OG3-r） by using a 75-g oral glucose load and HbAlc was measured by using high performance liquid chromatography （HPLC）. Subjects were classified as normal glucose tolerance （NGT）, pre-diabetes（impaired glucose regulation, IGR） and new diagnosed diabetes （NDD） per 1999 WHO criteria. Two tests are compared with receiver operating characteristic curve （ROC）. Results Among 1973 subjects, 271 （13.7%） were diagnosed as NDD and 474 （24.0%） as IGR by using OGTT. HbAlc was 5.7%_＋0.7% in this population. Use of 6.5% as the HbAIC cutoff point has sensitivity of 38.7% and specificity of 98.5%. We recommend 6.0% as a better cutoff value for diagnosis of diabetes in this population （AUC 0.829, 95% CI 0.798-0.860, P〈0.001） with its sensitivity and specificity as 66.1% and 86.8%. For IGR, the results showed low sensitivity （44.9%） and specificity （66.7%） with an AUC of 0.571 for HbAlc when 5.8% was used as the cutoff point. Participants detected with HbAlc_〉6.0% were associated with nearly the same metabolic characteristics, including body mass index （BMI）, blood pressure, lipid profile and urine albumin-creatinine ratio （uACR） compared with diabetic subjects detected by OGTT. Conclusion The optimum HbAlc cutoff point for diabetes in our study population was lower than ADA criteria, and HbAlc may not be used to identify IGR.

Association between serum uric acid and different states of glucose metabolism and glomerular filtration rate

Background Recently, it has been suggested that the serum uric acid （SUA） level decreased in diabetic patients. The aim of this study was to explore the association between SUA level and different state of glucose metabolism and glomerular filtration rate （GFR） reflected by the simplified Modification of Diet in Renal Disease （MDRD） equation and to test the hypothesis that high MDRD is one of the determinants of SUA level.Methods This cross-sectional study included 2373 subjects in Beijing who underwent a 75 g oral glucose tolerance test （OGTT） for screening of diabetes. According to the states of glucose metabolism, they were divided into normal glucose tolerance, impaired glucose regulation and diabetes.Results Multiple stepwise linear regression analysis showed that adjusted by gender, SUA was positively correlated with body mass index （BMI）, waist/hippo ratio, systolic blood pressure （SBP） and triglyceride, meanwhile negatively correlated with age, hemoglobin A1c, fasting insulin and MDRD. There was an increasing trend in SUA concentration and a decreasing trend in MDRD when the levels of fasting plasma glucose （FPG） increased from low to high up to the FPG level of 8.0 mmol/L; thereafter, the SUA concentration started to decrease with further increases in FPG levels, and the MDRD started to increase with further increases in FPG levels.Conclusion This study confirmed the previous finding that SUA decreased in diabetes and provided the supporting evidence that the increased MDRD might contribute to the fall of SUA.

Urine glucose levels are disordered before blood glucose level increase was observed in Zucker diabetic fatty rats

Many patients with diabetes are not diagnosed at all or are diagnosed too late to be effectively treated, resulting in nonspecific symptoms and a long period of incubation of the disease. Pre-diabetes is an early warning signal of diabetes, and the change of urine glucose in this period has been ignored even though urine has long been related with diabetes. In this study, Zucker diabetic fatty (ZDF) rats were used to test if there were changes in urine glucose before blood glucose increases. Six 8-week-old male ZDF rats (fa/fa) and Zucker lean (ZL) rats (fa/+) were fed with Purina 5008 high-fat diet and tested for fasting blood glucose and urine glucose. After 12 weeks of feeding, the urine glucose values of the ZL rats were normal (0–10 mmol L^(-1)), but the values of the ZDF model rats increased 10 weeks before their blood glucose levels elevated. The urine glucose values of the ZDF model rats showed a state of disorder that was frequently elevated (>10 mmol L^(-1)) and occasionally normal (0–10 mmol L^(-1)). This finding may provide an easy early screening for diabetes by long-term monitoring of urine glucose levels: pre-diabetes may be revealed by frequently disordered urine glucose levels over a period.

Association between Genetic Variants and Characteristic Symptoms of Type 2 Diabetes:A Matched Case-Control Study

Objective： To examine the association of genetic variants with characteristic symptoms of type 2 diabetes mellitus （T2DM）. Methods： A matched case-control study was performed to investigate the association between common variants in four genes （CDKAL1, GLIS3, GRK5, and TCFTL2） and symptoms of T2DM. Symptoms were examined with questionnaire for 710 subjects. Genomic DNA was extracted from peripheral blood mononuclear cell by salting-out procedure. Genotyping was carried out by direct sequencing of the unpurified polymerase chain reaction products. Result： Most of the T2DM patients pressented characteristic symptoms, such as feeling weak in limbs （P=0.0057）, hand tremor （P=0.0208）, bradymasesis （P=0.0234）, and polyuria （P=0.0051）. Some of the T2DM patients shared characteristic symptoms, such as desire for cold drinks （P=0.0304）, polyphagia （P=0.0051）, and furred tongue （P=0.028）. The impaired glucose regulation （IGR） cases took only one characteristic symptom of frequent micturition （P=0.0422）. GLIS3 rs7034200 and GRK5 rs10886471 were significantly associated with increased T2DM risk （GLIS3 rs7034200 under dominant model： P=0.0307; GRK5 rs 10886471 under recessive model： P=0.0092）. However, only the rs10886471 polymorphism in GRK5 showed a significant effect on both differentiated symptoms and T2DM risk. The C-allele was involved in both dampness-heat encumbering Pi （Spleen） syndrome （P=0.047） and qi-yin deficiency syndrome （P=0.002） via increased GRK5 expression. Conclnsions： Both T2DM and IGR exhibited its corresponding characteristic symptoms. The variants of GRK5 were involved with both qi-yin deficiency syndrome and dampness-heat encumbering Pi syndrome.