ABSTRACT
Objective • To investigate the relationship of hemoglobin A1c (HbA1c) with blood viscosity and peripheral arterial blood flow in patients with type 2 diabetes mellitus (T2DM). Methods • A total of 345 patients with T2DM were divided into four groups according to the HbA1c levels: group A (HbA1c<7.0%, 79 cases), group B (7.0% ≤ HbA1c<8.5%, 94 cases), group C (8.5% ≤ HbA1c<10.0%, 95 cases) and group D (HbA1c ≥ 10.0%, 77 cases). All patients were tested for blood glucose, HbA1c, blood viscosity and peripheral arterial ultrasound. Spearman and Pearson correlation as well as stepwise multivariate regression analyses were performed to analyze the data. Results • The whole blood viscosities at 1/s, 5/s, 30/s and 200/s shear rates of group B, C and D (HbA1c ≥ 7%) were significantly higher than those of group A (HbA1c<7.0%). The high shear reduction viscosities of group C and D (HbA1c ≥ 8.5%) were significantly higher than those of group A and B (HbA1c<8.5%). Spearman correlation analysis demonstrated that HbA1c was positively correlated with whole blood viscosities at 5/s, 30/s and 200/s shear rates and high shear reduction viscosity (HSRV) (P<0.05). In stepwise multivariate regression analysis, HbA1c had positive correlations with the whole blood viscosities at 5/s, 30/s and 200/s shear rates and HSRV after being adjusted for other factors (P<0.05). HbA1c showed significantly negative correlations with the left and right internal carotid arterial inner diameters after being corrected for relevant factors (P<0.05). Conclusion • The blood HbA1c levels in T2DM patients are positively correlated with blood viscosity, and HSRV, and negatively correlated with left and right internal carotid arterial inner diameters, but have no significant correlation with peripheral arterial blood flow velocity.
ABSTRACT
Objective: To investigate the characteristics of insulin secretion function and sensitivity and blood glucose disposition capacity in the prediabetes populations. Methods: A total of 1 317 subjects were enrolled in this study, including 382 with normal glucose tolerance (NGT) and 935 with pre-diabetes. All pre-diabetes populations were divided into seven subgroups according to the cut-off points of 2010 American Diabetes Association standards. Homeostasis model assessment (HOMA) was used to access baseline insulin secretion (HOMA-β) and insulin sensitivity (HOMA-IR). Insulin secretion and sensitivity after glucose load were evaluated by area under curve (AUC) for insulin/AUC for glucose (AUCINS120/AUCGLU120) and insulin sensitivity index (ISI) calculated from Cederholm formula, respectively. Disposition index (DI) was used to reflect blood glucose disposition capacity. Results: The most common type of pre-diabetes was impaired fasting glucose (IFG) combined with impaired glucose tolerance (IGT) and glycated hemoglobin A1c (HbA1c ) 5.7%-6.4%, followed by isolated IGT, while the proportion of isolated IFG was the lowest. The insulin sensitivity of isolated HbA1c 5.7%-6.4% group was better than that of isolated IFG group, isolated IGT group, and IFG combined with IGT group (P<0.05). And its β-cell function was similar with the other subgroups. The DI value of isolated HbA1c 5.7%-6.4% group was about 1.5 times of that of isolated IGT group and IFG combined with IGT group (P=0.000), which was similar with isolated IFG group. The function of β cell or insulin sensitivity in the pre-diabetes subjects with HbA1c 5.7%-6.4% was further damaged compared with the pre-diabetes people whose HbA1c were lower than 5.7%. Conclusion: Different types of pre-diabetes are significantly heterogeneous under new diagnostic criteria, and further prospective studies with a larger sample size are needed to clarify whether HbA1c 5.7%-6.4% is suitable as a diagnostic criteria for pre-diabetes in Chinese population.
ABSTRACT
PURPOSE: To report a case of bilateral diabetic papillopathy related to rapid hemoglobin A1c (HbA1c) decrease in a type I diabetic patient. CASE SUMMARY: A 39-year-old female who was diagnosed with type I diabetes mellitus for the first time at this hospital was presented to our clinic for evaluation of diabetic retinopathy. There were no subjective symptoms, including blurred vision or visual defect. Her best corrected visual acuity in both eyes was 1.0, but her fundus resembled mild nonproliferative diabetic retinopathy. When diagnosed with type I diabetes mellitus, her HbA1c was 15.3%. She used insulin to control her blood glucose and her HbA1c reached 7.3% two months after controlling the blood glucose. Three months after her diabetic diagnosis, there were no differences in subjective symptoms and best corrected visual acuity. Fundus examination showed optic disc swelling in both eyes. To evaluate for the etiology of optic disc swelling, we did the examinations of the optic disc, fundus, and brain magnetic resonance imaging. No specific signs were observed. We diagnosed diabetic papillopathy and observed the patient without any treatments. Her optic disc swelling showed gradual improvement. CONCLUSIONS: This case shows that the rapid HbA1c decrease in type I diabetes mellitus is related to the occurrence of bilateral diabetic papillopathy. This supports previous studies that estimated that the rapid HbA1c decrease in type I diabetes mellitus in response to insulin treatment is one of the risk factors for bilateral diabetic papillopathy.
Subject(s)
Adult , Female , Humans , Blood Glucose , Brain , Diabetes Mellitus , Diabetic Retinopathy , Diagnosis , Insulin , Magnetic Resonance Imaging , Risk Factors , Visual AcuityABSTRACT
Objective To research the changes of calcium regulation hormone and bone mineral density (BMD) in type 2 diabetes mellitus (T2DM ) patients and analyze the main impact factors. Methods 117 T2DM patients (T2DM group ,M/F=52/65 ,age 40~79 years) and 63 age‐ and gender‐matched healthy people (NC group) were selected in this study. According to the course of diabetes ,blood glucose control and the value of BMD ,T2DM patients were divided into subgroups :course≤10 years ,and>10 years ;HbA1 c≤8% ,and>8% ;normal BMD ,osteopenia ,and osteoporosis (OP). Serum 25‐hydroxy vitamin D3 [25(OH)D3 ]and Parathormone (PTH) were measured and BMDs of lumbar spine (L1 ~L4 ) , femoral neck ,total hip ,and whole body were evaluated for all the subjects. Result (1)Compared with NC group ,the level of serum 25(OH)D3 and BMDs of femoral neck and total hip decreased significantly in T2DM group[ (35.57 ± 12.30)nmol/L ,(0.848 ± 0.136)g/cm2 ,(0.873 ± 0.150)g/cm2 vs(44.94 ± 17.40) nmol/L ,(0.927 ± 0.173)g/cm2 ,(0.934 ± 0.140)g/cm2 ,respectively ,P10 years[ (0.814 ± 0.148) ,(0.840 ± 0.157) vs (0.882 ± 0.111) ,(0.908 ± 0.139) g/cm2 ,respectively ,P0.05). (3)Compared with HbA1c≤8% group ,BMD of femoral neck and total hip in HbA1c> 8% group decreased [(0.830 ± 0.131) ,(0.832 ± 0.161) vs (0.891 ± 0.130) ,(0.949 ± 0.130)g/cm2 ,respectively ,P 0.05). (4)The rates of OP and osteopenia (41.03% ,47.86% ) in T2DM were higher than those in NC group (26.98% ,33.33% ) (χ2 =4.367 ,4.669 ,P<0.05). The duration of diabetes and the levels of HbA1c and PTH were longer or higher in OP group than those with normal BMD or osteopenia (P<0.05). (5)Logistic regression analysis showed that BMD negatively correlated with the duration of diabetes ,HbA1c ,and PTH (β= 0.076 ,0.213 ,0.112 ,respectively ,P< 0.05) ,and positively correlated with 25(OH)D3 (β= -0.043 ,P<0.05). Conclusion The values of BMD decreased and the incidence of OP is higher in T2DM patients ,particularly in patients with longer diabetic duration and poor glycemic control.
ABSTRACT
BACKGROUND: The hemoglobin A1c (HbA1c) level is widely used to monitor glycemic control in diabetes mellitus patients, and various methods are used for its determination. The CAPILLARYS 2 FLEX Piercing (Sebia) is a fully automated, high-throughput glycohemoglobin (HbA1c) analyzer based on capillary electrophoresis. METHODS: The analytical performance of the CAPILLARYS 2 FLEX Piercing analyzer was evaluated for its precision, linearity, correlation with the Variant II Turbo (Bio-Rad Laboratories, Inc.) analyzer, and its vulnerability to interference by carbamylated hemoglobin. We also investigated its agreement with National Glycohemoglobin Standardization Program (NGSP) targets. All evaluations were performed according to CLSI guidelines EP05, EP06, and EP09. RESULTS: The coefficients of variation (CVs) for within-run and total imprecision were 1.7% and 1.8% at low concentrations and 1.2% and 1.3% at high concentrations, respectively. Linearity was excellent, with R2=0.9882 in the range of 5.13-13.83%; these results highly correlated with those produced by Variant II Turbo (R2=0.9978). The 95% confidence interval (for differences from the NGSP target) was -0.3618-0.3343%. No significant interference of carbamylated hemoglobin was noted. CONCLUSIONS: The CAPILLARYS 2 FLEX Piercing analyzer showed excellent precision and linearity. Its results correlated with those obtained by the Variant II Turbo analyzer, and were agreement with the NGSP target. Therefore, its analytical performance is satisfactory for diabetes diagnosis and treatment monitoring.
Subject(s)
Humans , Capillaries , Diabetes Mellitus , Electrophoresis, Capillary , Hemoglobins , Organothiophosphorus CompoundsABSTRACT
BACKGROUND: Hemoglobin (Hb)-A1c is routinely used for the management of diabetes. In 2010, HbA1c was included into the diagnostic criteria for diabetes by the American Diabetes Association. A newly developed HbA1c analyzer, ARKRAY ADAMS HA-8180 (ARKRAY KDK, Japan) was introduced. In this study, we evaluated the analytical performance of ARKRAY ADAMS HA-8180 HbA1c analyzer and compared it with the previously used Variant II Turbo (Bio-Rad Laboratories, USA), which is a National Glycohemoglobin Standardization Program (NGSP) certified analyzer. METHODS: According to Clinical Laboratory and Standards Institute (CLSI) evaluation protocol (EP) 5-A, Lyphochek Diabetes Controls (Bio-Rad Laboratories, USA) are used for precision. Two (low and high) levels of quality control materials were analyzed twice a day for 20 days, after which the mean, total standard deviation (SD) and total coefficient of variation (CV), including the between-run CV and between-day CV were calculated. ARKRAY ADAMS HA-8180 HbA1c analyzer and Variant II Turbo were compared with 150 samples according to CLSI EP9-A2. In addition, the linearity and carry over rate were evaluated. RESULTS: Between-run CVs for low and high level quality control materials were 0.0% and 0.3%, respectively, whereas between-day CVs for low and high level quality control materials were 0.3% and 0.2%, respectively. In the linearity test, the coefficient of determination (R2) was 0.99 (range, 3.1-19.3%). Thus, a good correlation was observed between ARKRAY ADAMS HA-8180 HbA1c analyzer and Variant II Turbo (R2=0.994). The carry over rate was 0.0%. CONCLUSIONS: The ARKRAY ADAMS HA-8180 HbA1c analyzer showed excellent precision, linearity, and carryover rate. It also showed excellent correlation with the NGSP certified Variant II Turbo. In conclusion, the ARKRAY ADAMS HA-8180 HbA1c analyzer is a reliable high-performance liquid chromatography (HPLC) analyzer for HbA1c analysis and could be very useful for the diagnosis, treatment, monitoring, and risk assessment of diabetes.
Subject(s)
Chromatography, Liquid , Hemoglobins , Quality Control , Risk AssessmentABSTRACT
BACKGROUND: Hemoglobin (Hb)-A1c is routinely used for the management of diabetes. In 2010, HbA1c was included into the diagnostic criteria for diabetes by the American Diabetes Association. A newly developed HbA1c analyzer, ARKRAY ADAMS HA-8180 (ARKRAY KDK, Japan) was introduced. In this study, we evaluated the analytical performance of ARKRAY ADAMS HA-8180 HbA1c analyzer and compared it with the previously used Variant II Turbo (Bio-Rad Laboratories, USA), which is a National Glycohemoglobin Standardization Program (NGSP) certified analyzer. METHODS: According to Clinical Laboratory and Standards Institute (CLSI) evaluation protocol (EP) 5-A, Lyphochek Diabetes Controls (Bio-Rad Laboratories, USA) are used for precision. Two (low and high) levels of quality control materials were analyzed twice a day for 20 days, after which the mean, total standard deviation (SD) and total coefficient of variation (CV), including the between-run CV and between-day CV were calculated. ARKRAY ADAMS HA-8180 HbA1c analyzer and Variant II Turbo were compared with 150 samples according to CLSI EP9-A2. In addition, the linearity and carry over rate were evaluated. RESULTS: Between-run CVs for low and high level quality control materials were 0.0% and 0.3%, respectively, whereas between-day CVs for low and high level quality control materials were 0.3% and 0.2%, respectively. In the linearity test, the coefficient of determination (R2) was 0.99 (range, 3.1-19.3%). Thus, a good correlation was observed between ARKRAY ADAMS HA-8180 HbA1c analyzer and Variant II Turbo (R2=0.994). The carry over rate was 0.0%. CONCLUSIONS: The ARKRAY ADAMS HA-8180 HbA1c analyzer showed excellent precision, linearity, and carryover rate. It also showed excellent correlation with the NGSP certified Variant II Turbo. In conclusion, the ARKRAY ADAMS HA-8180 HbA1c analyzer is a reliable high-performance liquid chromatography (HPLC) analyzer for HbA1c analysis and could be very useful for the diagnosis, treatment, monitoring, and risk assessment of diabetes.
Subject(s)
Chromatography, Liquid , Hemoglobins , Quality Control , Risk AssessmentABSTRACT
BACKGROUND: Hemoglobin A1c (HbA1c) is a useful marker for the diagnosis and monitoring of diabetes, which has resulted in an increasing dependency on HbA1c levels for diagnosing diabetes in small- and medium-sized hospitals. We evaluated a high performance liquid chromatography (HPLC) based HbA1c autoanalyzer Bio-Rad D-10 (Bio-Rad Laboratories, USA) by comparing the analysis results with that by Tosoh HLC-723 G7 (Tosoh Corporation, Japan). METHODS: The Bio-Rad D-10 autoanalyzer was evaluated for its precision, linearity, and carryover. The analysis time and correlation were evaluated and compared with those by Tosoh HLC-723 G7 autoanalyzer. RESULTS: Bio-Rad D-10 showed within-run, between-day, and total precision of less than 1.3% coefficient of variation (CV) and excellent linearity between HbA1c in the range of 3.2%-21% (coefficient of determination, R 2 = 0.998). The sampleto-sample carryover was 0.57%. The results obtained by using Bio-Rad D-10 showed good correlation (r = 0.997; P < 0.001) with those by Tosoh HLC-723 G7; however, the analysis time using Bio-Rad D-10 was about 2.3 times per 10 samples and 2.5 times per 20 samples than those using Tosoh HLC-723 G7. CONCLUSIONS: Bio-Rad D-10 showed good performance in assaying HbA1c. Bio-Rad D-10 autoanalyzer would be suitable for use in laboratories with small to medium amount of samples to be analyzed, but its initial analyzing time was longer than that by Tosoh HLC-723 G7.
Subject(s)
Chromatography, Liquid , Dependency, Psychological , HemoglobinsABSTRACT
BACKGROUND: Hemoglobin A1c (HbA1c) levels are widely used to monitor glycemic control in diabetes mellitus patients, and various methods are used for determining HbA1c levels. The ADAMS A1c HA-8180 (Arkray, Inc., Japan) is a fully automated HbA1c analyzer based on high-performance liquid chromatography (HPLC). METHODS: The analytical performance of the ADAMS A1c HA-8180 analyzer was evaluated on the basis of its precision, linearity, correlation with the Variant II Turbo (Bio-Rad Laboratories, USA), and agreement with the National Glycohemoglobin Standardization Program (NGSP) targets. All evaluations were performed according to Clinical and Laboratory Standard Institute (CLSI) guidelines EP05, EP06, and EP09. RESULTS: Coefficients of variation (CVs) for total precision at low and high levels were 0.99% and 1.16%, respectively. The linearity was excellent with R2 = 0.99 in the range of 4.98-15.10%. Its analytical performance was well correlated with that of Variant II Turbo (r = 0.9987). The 95% confidence interval of bias between the NGSP target and the levels measured using the ADAMS A1c HA-8180 was -0.402-0.225. CONCLUSIONS: The ADAMS A1c HA-8180 showed excellent precision, linearity, correlation with Variant II Turbo, and agreement with the NGSP target. Therefore, its analytical performance is satisfactory for diagnosis and treatment monitoring of diabetes.
Subject(s)
Humans , Bias , Chromatography, Liquid , Diabetes Mellitus , Hemoglobins , Organothiophosphorus CompoundsABSTRACT
BACKGROUND: Hemoglobin A1c (HbA1c) is widely used for the monitoring of glycemic control in diabetes mellitus patients. Various methods are applied for the determination of HbA1c levels. Recently, a novel National Glycohemoglobin Standardization Program (NGSP)-certificated reagent (AutoLab HbA1c, IVD-LAB, Korea) was introduced for use in an automated chemistry analyzer. We evaluated the analytical performance of this immunoturbidimetry reagent and compared it with the ion-exchange high performance liquid chromatography (Variant II Turbo, Bio-Rad Laboratories, Inc., USA) and immunoassay (Cobas Integra 800, Roche Diagnostics, Germany) methods. METHODS: Toshiba 200FR NEO (Toshiba Medical Systems Co., Japan) with the AutoLab reagent was evaluated for precision, linearity, carryover and compared with Cobas Integra and Variant II Turbo. RESULTS: Coefficients of variation (CVs) of within-run imprecision for low and high level were 1.8% and 0.7%, respectively. CVs of within-laboratory imprecision for low and high level were 2.4% and 1.0%, respectively. The linearity was excellent with R2 = 0.99 in the range of 3.05-15.50%. It was well correlated with Variant II Turbo (R=0.9904) and Cobas Integra 800 (R=0.9992). The carryover rate was 0.4%. CONCLUSIONS: The Toshiba 200FR NEO with the AutoLab reagent showed excellent precision and linearity and minimal carryover rate. It was well correlated with the other widely used methodological instruments. It may be used for the diagnosis and the treatment monitoring of diabetes.
Subject(s)
Humans , Chromatography, Liquid , Diabetes Mellitus , Hemoglobins , ImmunoassayABSTRACT
BACKGROUND: Hemoglobin A1c (HbA1c) is a good marker for the monitoring of glycemic control in patients with diabetes mellitus and various methods are used for determination of HbA1c. We evaluated the analytical performance of ion-exchange high-performance liquid chromatography system, standard mode (G8 SM) and variant mode (G8 VM) of Tosoh HLC-723 G8 (Tosoh Corporation, Japan) and Cobas Integra 800 (Roche Diagnostics, Germany) using new reagent (Tina-quant Hemoglobin A1c Gen.2, Roche Diagnostics) for immunoassay. METHODS: G8 SM, G8 VM, and Cobas Integra 800 were evaluated for linearity, precision, comparison of method, and speed. Variant II Turbo (Bio-Rad Laboratories, USA) was used for comparison test for above three analyzers. RESULTS: Three instruments showed within-run precision (CVs) of 0.52-1.12% in low level and 0.39-0.90% in high level control material. Total run precision (CVs) were in 0.95-1.26% in low level and 0.60-0.94% in high level control material. The linearity was good for the range of 4-15% and comparison with Variant II turbo was excellent with 0.9878-0.9977 of correlation coefficient. Analytical speed was 2 min/1 min in G8 SM, 3.5 min/1.5 min in G8 VM, and 14.7 min/18 sec in Cobas Integra 800, respectively. CONCLUSIONS: HLC-723 G8 SM and VM, and Cobas Integra 800 were showed excellent linearity, precision, and comparison with other instrument. We should consider the characteristics including analytical method and speed in each instrument when clinical laboratory is planning to introduce different equipment for HbA1c determination.
Subject(s)
Humans , Chromatography, High Pressure Liquid , Chromatography, Liquid , Diabetes Mellitus , Hemoglobins , ImmunoassayABSTRACT
BACKGROUND: Hemoglobin A1c (HbA1c) is widely used for the diagnosis of diabetes and monitoring of glycemic control. Recently, there is an increasing demands of HbA1c as an emergency outpatient test. We performed this study to evaluate the clinical utility of Dimension HbA1c immunoassay (Dade Behring, Newark, DE, USA). METHODS: Dimension HbA1c was evaluated for linearity, precision, method comparison, and speed. It was compared with VARIANT II Turbo (Bio-Rad Laboratories, Hercules, CA, USA). RESULTS: Dimension HbA1c showed within-run and total imprecision (CVs) of less than 2.0% and 2.5%, respectively. It revealed a good linearity to about 20%. Comparison studies between Dimension HbA1c and VARIANT II Turbo yielded a good correlation (r=0.990). The elapsed time for analysis was 7.5 min for the first specimen and 0.5 min for the succeeding ones. CONCLUSIONS: Dimension HbA1c provides acceptable performances and is suitable for the the emergency outpatient test.
Subject(s)
Humans , Emergencies , Hemoglobins , Immunoassay , OutpatientsABSTRACT
BACKGROUND: Hemoglobin A1c (HbA1c) is widely used for the monitoring of glycemic control. A wide variety of different analytical methods is currently used by clinical laboratories. We performed this study to evaluate the newest ion-exchange high-performance liquid chromatography system, the HLC-723 G7 (Tosoh Corporation, Tokyo, Japan) automated glycohemoglobin analyzer. METHODS: HLC-723 G7 was evaluated for linearity, precision, comparison of method, and speed. HLC-723 G7 was compared with three analyzers including HLC-723 GHb V A1c 2.2, Variant II, and Cobas Integra 800. RESULTS: HLC-723 G7 showed within-run and total imprecision (CVs) of less than 2.5% and excellent linearity to at least 13.0%. HbA1c values obtained from HLC-723 G7 were strongly correlated with those from HLC-723 GHb V A1c 2.2. Comparison with two other methods showed a good correlation but revealed calibration differences throughout the analytical range. HLC-723 G7 required no sample preparation and showed a fast analytical time of 1.6 min. CONCLUSIONS: HLC-723 G7 provides high throughput and excellent precision. However, HbA1c values can differ considerably with different methods or instruments. Therefore, we should be aware of the potential problem in switching the HbA1c testing method
Subject(s)
Calibration , Chromatography, High Pressure Liquid , Chromatography, Liquid , Diabetes MellitusABSTRACT
BACKGROUND: We evaluated the performance of the TOSOH glycohemoglobin analyzer HLC-723GHb V A1c 2.2TM (TOSOH Corp. Kyoto, Japan), a recently introduced automated hemoglobin A1c (HbA1c) analyzer using high performance liquid chromatography (HPLC) method without sample pretreatment. METHODS: The performance characteristics evaluated were precision, linearity, comparison with VARIANTTM (Bio-Rad, Germany) and throughput following NCCLS evaluation protocols (EP5-T2, EP6-P, and EP9-T). RESULTS: The within-run and between-day CV's were 0.910 and 1.328 for low level (6.2%), 1.214 and 1.460 for middle level (8.5%), and 0.789 and 1.449 for high level (10.7%), respectively. We found the perfect linearity of HbA1c (%) from 6.5 to 10.2 (r2=0.9995). Comparison studies between A1c 2.2 and VARIANTTM yielded the following correlation equations; A1c 2.2TM = 0.9915 (VARIANTTM) + 0.1198 %HbA1c (r=0.9936, P < 0.0001). Throughput was 28.0 tests per hour for A1c 2.2TM compared with 15.2 tests for VARIANTTM, which were determined including red blood cell lysis time before sample loading for VARIANTTM. A1c 2.2TM did not need sample pretreatment. CONCLUSIONS: With the above results, A1c 2.2TM shows acceptable performance and is suitable for routine use in the clinical laboratory.