Humans ; Glycated Hemoglobin ; Diabetes Mellitus, Type 1 ; Blood Glucose ; Diabetes Mellitus, Type 2

To explore the application value of serum Gal-13, GLP-1 and VEGF in the prevention and guidance of adverse pregnancy outcomes in gestational diabetes (GDM). A retrospective study with case-control method was used to select 1 012 GDM patients from Haikou Maternal and Child Health Hospital from January 2019 to December 2022 as the study objects, and they were divided into poor pregnancy outcome group (n=342) and good pregnancy outcome group (n=670) according to whether they had adverse pregnancy outcomes. The medical records of 521 healthy women with normal glucose metabolism were selected as the control group. Serum Gal-13 and GLP-1 were detected by enzyme-linked immunosorbent assay and VEGF was determined by IAMMGE specific protein analyzer. After comparing the differences of the above factors among the three groups, multivariate logistic regression model was used to analyze the influencing factors of adverse pregnancy outcomes in GDM patients, and ROC curve was drawn to analyze the predictive value of serum Gal-13, GLP-1 and VEGF levels on adverse pregnancy outcomes in GDM patients. The results showed that Fasting blood glucose (FPG), glycosylated hemoglobin (HbA1c) and fasting insulin (FINS) in the adverse pregnancy outcome group were 5.92(4.98, 6.41) mmol/L, 5.32(4.96, 5.47)%, 62.56(49.21,99.50) pmol/L, VEGF was 495.47(389.14, 567.13) ng/L, TSH was 1.48(1.34, 1.58) mIU/L, right ventricular myocardial work index (Tei index) was 0.59(0.45, 0.67), 89 cases of elderly parturients; FPG was 4.45(4.16, 5.03) mmol/L, HbA1c was 5.04(4.86, 5.29)%, FINS was 57.41(46.90, 74.08) pmol/L, VEGF was 405.84(348.02, 462.68) ng/L, TSH was 1.42(1.25, 1.50) mIU/L, Tei index was 0.50(0.47, 0.64), there were 142 cases of old women. In the control group, FPG was 4.33(4.05, 4.75) mmol/L, HbA1c was 5.01(4.13, 5.18)%, FINS was 38.48(36.76, 41.72) pmol/L and VEGF was 302.45(283.14, 336.56) ng/L, TSH was 1.32(1.24, 1.47)mIU/L, Tei index was 0.48(0.39, 0.59), and there were 106 elderly parturiencies. The levels of FPG, HbA1c, FINS, VEGF, TSH and Tei index in the adverse pregnancy outcome group and the good pregnancy outcome group were higher than those in the control group, and the proportion of elderly parturients was higher than that in the control group, and the adverse pregnancy outcome group was higher than that in the good pregnancy outcome group. The differences were statistically significant (H=8.620, P<0.001, H=2.616, P=0.014, H=6.156, P<0.001, H=3.051, P<0.001, H=4.892, P=0.044, χ²=2.548, P=0.045). In the adverse pregnancy outcome group, Gal-13 was 15.27(8.35, 24.45)pg/ml, GLP-1 was 9.27(8.26, 12.35) pmol/L and FT4 was 11.59(9.67, 13.48) pmol/L. In the group with good pregnancy outcome, Gal-13 was 25.34(20.14, 29.73) pg/ml, GLP-1 was 12.38(10.25, 15.63) pmol/L and FT4 was 13.86(10.67, 15.10) pmol/L. In the control group, Gal-13 was 31.21(27.48, 34.45) pg/ml, GLP-1 was 11.34(10.40, 14.37) pmol/L and FT4 was 14.15(10.75, 15.43)pmol/L. The levels of Gal-13, GLP-1 and FT4 in the adverse pregnancy outcome group and the good pregnancy outcome group were significantly lower than those in the control group, and the adverse pregnancy outcome group was lower than that in the good pregnancy outcome group. The differences were statistically significant (H=6.458, P=0.011, H=8.445, P<0.001, H=5.694, P<0.001). The levels of Gal-13 and GLP-1 in normal blood glucose recovery group were higher than those in non-normal blood glucose recovery group, and the levels of VEGF were lower than those in non-normal blood glucose recovery group (P<0.05).In multivariate logistic regression analysis, Gal-13, GLP-1, VEGF, TSH, FT4 and Tei indexes were independent influencing factors for adverse pregnancy outcomes with GDM (P<0.05). ROC curve analysis showed that the AUC of Gal-13, GLP-1 and VEGF alone in predicting adverse pregnancy were 0.779, 0.761 and 0.615, respectively. The value of the combined diagnosis was the highest (AUC=0.912), the sensitivity was 90.1%, and the specificity was 80.0%. In conclusion, Gal-13, GLP-1 and VEGF may be independent influencing factors for adverse pregnancy outcomes in GDM patients, and the combined detection of the three may help to improve the auxiliary diagnostic efficacy for predicting adverse pregnancy outcomes.
Aged ; Child ; Female ; Humans ; Pregnancy ; Blood Glucose ; Diabetes, Gestational ; Glucagon-Like Peptide 1 ; Glycated Hemoglobin ; Pregnancy Outcome ; Retrospective Studies ; Thyrotropin ; Vascular Endothelial Growth Factor A

To determine the types and proportion of common hemoglobin variants in Tianjin and surrounding areas, to analyze the recognition ability and the effects of hemoglobin variants on experimental results in two commonly used glycated hemoglobin systems, so as to provide data support for the consistency of HbA1c detection in Tianjin City. A case-control study was used for retrospective analysis,156 specimens with abnormal electrophoretic peaks in the detection of glycated hemoglobin were collected from more than 50 000 specimens of patients in Chu Hsien-I Memorial Hospital of Tianjin Medical University between June 2020 and December 2020. Determined their hemoglobin mutation sites by DNA sequencing, and compared the values of hemoglobin variants on glycated hemoglobin detection values by high performance liquid chromatography and capillary electrophoresis. SPSS 23 was used to calculate the blood routine results of the variant specimens, and compared with the normal reference interval. The results showed that DNA sequencing identified 21 hemoglobin variants, of which 11 were α strand variants and 10 were β strand variants. In addition, an unreported hemoglobin variant was identified, Hb Headington (HBB: c.217A>C). The HbA_1c of 11 variants including Hb G-Honolulu, Hb Queens, Hb Q-Thailand, Hb J-Broussais, Hb O-Indonesia, Hb G-Coushatta, Hb G-Taipei, Hb E, Hb Headington, Hb New York and Hb D-Los Angeles were shifted by more than 7% when measured by high-performance liquid chromatography. Patients with the Hb Q-Thailand and Hb E cause reduced MCV and MCH. In conclusion, an unreported hemoglobin variant was found from Tianjin and neighboring areas. Patients with the Hb Q-Thailand and Hb E cause reduced MCV and MCH. 11 of these hemoglobin variants interfered with the detection of glycated hemoglobin using high-performance liquid chromatography, resulting in inaccurate results.
Humans ; Glycated Hemoglobin ; Case-Control Studies ; Retrospective Studies ; Hospitals

To explore the application value of serum Gal-13, GLP-1 and VEGF in the prevention and guidance of adverse pregnancy outcomes in gestational diabetes (GDM). A retrospective study with case-control method was used to select 1 012 GDM patients from Haikou Maternal and Child Health Hospital from January 2019 to December 2022 as the study objects, and they were divided into poor pregnancy outcome group (n=342) and good pregnancy outcome group (n=670) according to whether they had adverse pregnancy outcomes. The medical records of 521 healthy women with normal glucose metabolism were selected as the control group. Serum Gal-13 and GLP-1 were detected by enzyme-linked immunosorbent assay and VEGF was determined by IAMMGE specific protein analyzer. After comparing the differences of the above factors among the three groups, multivariate logistic regression model was used to analyze the influencing factors of adverse pregnancy outcomes in GDM patients, and ROC curve was drawn to analyze the predictive value of serum Gal-13, GLP-1 and VEGF levels on adverse pregnancy outcomes in GDM patients. The results showed that Fasting blood glucose (FPG), glycosylated hemoglobin (HbA1c) and fasting insulin (FINS) in the adverse pregnancy outcome group were 5.92(4.98, 6.41) mmol/L, 5.32(4.96, 5.47)%, 62.56(49.21,99.50) pmol/L, VEGF was 495.47(389.14, 567.13) ng/L, TSH was 1.48(1.34, 1.58) mIU/L, right ventricular myocardial work index (Tei index) was 0.59(0.45, 0.67), 89 cases of elderly parturients; FPG was 4.45(4.16, 5.03) mmol/L, HbA1c was 5.04(4.86, 5.29)%, FINS was 57.41(46.90, 74.08) pmol/L, VEGF was 405.84(348.02, 462.68) ng/L, TSH was 1.42(1.25, 1.50) mIU/L, Tei index was 0.50(0.47, 0.64), there were 142 cases of old women. In the control group, FPG was 4.33(4.05, 4.75) mmol/L, HbA1c was 5.01(4.13, 5.18)%, FINS was 38.48(36.76, 41.72) pmol/L and VEGF was 302.45(283.14, 336.56) ng/L, TSH was 1.32(1.24, 1.47)mIU/L, Tei index was 0.48(0.39, 0.59), and there were 106 elderly parturiencies. The levels of FPG, HbA1c, FINS, VEGF, TSH and Tei index in the adverse pregnancy outcome group and the good pregnancy outcome group were higher than those in the control group, and the proportion of elderly parturients was higher than that in the control group, and the adverse pregnancy outcome group was higher than that in the good pregnancy outcome group. The differences were statistically significant (H=8.620, P<0.001, H=2.616, P=0.014, H=6.156, P<0.001, H=3.051, P<0.001, H=4.892, P=0.044, χ²=2.548, P=0.045). In the adverse pregnancy outcome group, Gal-13 was 15.27(8.35, 24.45)pg/ml, GLP-1 was 9.27(8.26, 12.35) pmol/L and FT4 was 11.59(9.67, 13.48) pmol/L. In the group with good pregnancy outcome, Gal-13 was 25.34(20.14, 29.73) pg/ml, GLP-1 was 12.38(10.25, 15.63) pmol/L and FT4 was 13.86(10.67, 15.10) pmol/L. In the control group, Gal-13 was 31.21(27.48, 34.45) pg/ml, GLP-1 was 11.34(10.40, 14.37) pmol/L and FT4 was 14.15(10.75, 15.43)pmol/L. The levels of Gal-13, GLP-1 and FT4 in the adverse pregnancy outcome group and the good pregnancy outcome group were significantly lower than those in the control group, and the adverse pregnancy outcome group was lower than that in the good pregnancy outcome group. The differences were statistically significant (H=6.458, P=0.011, H=8.445, P<0.001, H=5.694, P<0.001). The levels of Gal-13 and GLP-1 in normal blood glucose recovery group were higher than those in non-normal blood glucose recovery group, and the levels of VEGF were lower than those in non-normal blood glucose recovery group (P<0.05).In multivariate logistic regression analysis, Gal-13, GLP-1, VEGF, TSH, FT4 and Tei indexes were independent influencing factors for adverse pregnancy outcomes with GDM (P<0.05). ROC curve analysis showed that the AUC of Gal-13, GLP-1 and VEGF alone in predicting adverse pregnancy were 0.779, 0.761 and 0.615, respectively. The value of the combined diagnosis was the highest (AUC=0.912), the sensitivity was 90.1%, and the specificity was 80.0%. In conclusion, Gal-13, GLP-1 and VEGF may be independent influencing factors for adverse pregnancy outcomes in GDM patients, and the combined detection of the three may help to improve the auxiliary diagnostic efficacy for predicting adverse pregnancy outcomes.
Aged ; Child ; Female ; Humans ; Pregnancy ; Blood Glucose ; Diabetes, Gestational ; Glucagon-Like Peptide 1 ; Glycated Hemoglobin ; Pregnancy Outcome ; Retrospective Studies ; Thyrotropin ; Vascular Endothelial Growth Factor A

To determine the types and proportion of common hemoglobin variants in Tianjin and surrounding areas, to analyze the recognition ability and the effects of hemoglobin variants on experimental results in two commonly used glycated hemoglobin systems, so as to provide data support for the consistency of HbA1c detection in Tianjin City. A case-control study was used for retrospective analysis,156 specimens with abnormal electrophoretic peaks in the detection of glycated hemoglobin were collected from more than 50 000 specimens of patients in Chu Hsien-I Memorial Hospital of Tianjin Medical University between June 2020 and December 2020. Determined their hemoglobin mutation sites by DNA sequencing, and compared the values of hemoglobin variants on glycated hemoglobin detection values by high performance liquid chromatography and capillary electrophoresis. SPSS 23 was used to calculate the blood routine results of the variant specimens, and compared with the normal reference interval. The results showed that DNA sequencing identified 21 hemoglobin variants, of which 11 were α strand variants and 10 were β strand variants. In addition, an unreported hemoglobin variant was identified, Hb Headington (HBB: c.217A>C). The HbA_1c of 11 variants including Hb G-Honolulu, Hb Queens, Hb Q-Thailand, Hb J-Broussais, Hb O-Indonesia, Hb G-Coushatta, Hb G-Taipei, Hb E, Hb Headington, Hb New York and Hb D-Los Angeles were shifted by more than 7% when measured by high-performance liquid chromatography. Patients with the Hb Q-Thailand and Hb E cause reduced MCV and MCH. In conclusion, an unreported hemoglobin variant was found from Tianjin and neighboring areas. Patients with the Hb Q-Thailand and Hb E cause reduced MCV and MCH. 11 of these hemoglobin variants interfered with the detection of glycated hemoglobin using high-performance liquid chromatography, resulting in inaccurate results.
Humans ; Glycated Hemoglobin ; Case-Control Studies ; Retrospective Studies ; Hospitals

OBJECTIVE: To investigate the coagulation function indicators and identify influence factors of hypercoagulability in patients with adrenocorticotropic hormone (ACTH) independent Cushing syndrome (CS). METHODS: In our retrospective study, the electronic medical records system of Peking University First Hospital was searched for the patients diagnosed with ACTH independent CS on discharge from January 2014 to June 2019. Nonfunctional adrenal adenoma patients were chosen as control group and matched 1 ∶1 by body mass index (BMI), gender, and discharge date. Clinical features and coagulation function indicators were compared between the two groups. RESULTS: In the study, 171 patients were included in each group. Compared with control group, activated partial thromboplastin time (APTT), and prothrombin time (PT) in ACTH independent CS group were significantly lower [(29.22±3.39) s vs. (31.86±3.63) s, P < 0.001; (29.22±3.39) s vs. (31.86±3.63) s, P < 0.001], and both D-dimer and fibrin degradation products (FDP) levels were significantly higher (P < 0.05). Percentage of APTT levels under the lower limit of reference range in the CS patients was significantly higher than that in nonfunctional group (21.6% vs. 3.5%, P < 0.001). Percentage of D-dimer levels over the upper limit of reference range in the CS patients was significantly higher than that in nonfunctional group (13.5% vs. 6.6%, P=0.041). There were three patients with deep venous thrombosis and one patient with pulmonary embolism in CS group, however none was in control group. The area under curve (AUC) of serum cortisol rhythm (8:00, 16:00 and 24:00) levels was negatively associated with the levels of PT (r=-0.315, P < 0.001) and APTT (r=-0.410, P < 0.001), and positively associated with FDP (r=0.303, P < 0.001) and D-dimer levels (r=0.258, P < 0.001). There were no differences in coagulation function indicators among different histopathologic subgroups (adrenocortical adenoma, adrenocortical hyperplasia, oncocytic adenoma, adrenocortical carcinoma). With Logistic regression analysis, the AUC of cortisol and glycosylated hemoglobin A1c (HbA1c) levels were independent risk factors for hypercoagulability in the ACTH independent CS patients (P < 0.05). CONCLUSION ACTH independent CS patients were more likely in hypercoagulable state compared with nonfunctional adrenal adenoma, especially in ACTH independent CS patients with higher levels of cortisol AUC and HbA1c. These patients should be paid attention to for the hypercoagulability and thrombosis risk.
Humans ; Cushing Syndrome/complications* ; Adrenocortical Adenoma/complications* ; Adrenocorticotropic Hormone ; Hydrocortisone ; Retrospective Studies ; Glycated Hemoglobin ; Adrenal Cortex Neoplasms/diagnosis* ; Adenoma/diagnosis* ; Thrombophilia/complications*

OBJECTIVES: To investigate the cerebral metabolism in the patients with type 2 diabetes mellitus-associated cognitive dysfunction (T2DACD) and explore the mechanism of electroacupuncture (EA) at the acupoints for Tiaozang Xingshen (adjusting zangfu function and rescuing the spirit) in treatment of T2DACD, using magnetic resonance spectroscopy. METHODS: Fifteen patients with T2DACD (observation group) and 22 healthy subjects (control group) were enrolled. In the observation group, the patients were treated with EA for Tiaozang Xingshen at Baihui (GV 20) and Shenting (GV 24), and bilateral Feishu (BL 13), Pishu (BL 20), Shenshu (BL 23), Zusanli (ST 36), Sanyinjiao (SP 6), Hegu (LI 4) and Taichong (LR 3). EA was operated with disperse-dense wave, 2 Hz/100 Hz in frequency and 0.1 mA to 1.0 mA in current intensity; 30 min each time, once daily. One course of EA consisted of 5 treatments, at the interval of 2 days and the intervention lasted 8 courses. Before treatment in the control group, before and after treatment in the observation group, the score of Montreal cognitive assessment scale (MoCA), the score of clinical dementia rating (CDR), Flanker paradigm, Stroop paradigm, Nback paradigm, the score of self-rating anxiety scale (SAS), the score of self-rating depression scale (SDS), and the score of Hamilton depression rating scale (HAMD) were evaluated separately; the glycolipid metabolic indexes (fasting plasma glucose [FPG], glycosylated hemoglobin type A1c [HbA1c], total cholesterol [TC], triacylglycerol [TG], high-density lipoprotein cholesterol [HDL-C] and low-density lipoprotein cholesterol [LDL-C]) were determined；with the magnetic resonance spectroscopy technique adopted, the metabolites in the basal ganglia area were detected. The correlation analysis was performed for the metabolite values with MoCA score, CDR score , Flanker paradigm, Stroop paradigm, and Nback paradigm. RESULTS: Before treatment, compared with the control group, in the observation group, MoCA score was lower (P<0.001), CDR score and the levels of FPG and HbA1c were higher (P<0.001); the reaction times of Flanker non-conflict, Flanker conflict, Stroop neutrality, Stroop congruence, Stroop conflict, and 1-back were prolonged (P<0.05, P<0.001), and the accuracy of Flanker conflict, Stroop conflict, and 1-back decreased (P<0.05, P<0.01); the ratio of N-acetyl aspartate (NAA) to creatine (Cr) in the left basal ganglia area was dropped (P<0.001), and that of myo-inositol (MI) to Cr in the right side increased (P<0.05). In the observation group after treatment, compared with the levels before treatment, MoCA score was higher (P<0.001), the scores of CDR, SAS and HAMD were reduced (P<0.01, P<0.05), the reaction times of Flanker conflict and Stroop conflict shortened (P<0.001, P<0.05), and the accuracy of Flanker conflict and 1-back increased (P<0.001, P<0.05); the ratio of NAA to Cr in the left basal ganglia area and that of the gamma-aminobutyric acid (GABA) to Cr in the right increased (P<0.05), that of MI to Cr in the right decreased (P<0.05). Before treatment, in the observation group, the ratio of MI to Cr in the right basal ganglia area was positively correlated with the reaction time of Stroop congruence (r=0.671, P=0.012) and this ratio was positively correlated with the reaction time of Stroop conflict (r=0.576, P=0.039). CONCLUSIONS Electroacupuncture for "adjusting zangfu function and rescuing the mind" improves the cognitive function of T2DACD patients, which may be related to the regulation of NAA, MI and GABA levels in the basal ganglia.
Humans ; Electroacupuncture ; Acupuncture Therapy ; Acupuncture Points ; Diabetes Mellitus, Type 2/therapy* ; Glycated Hemoglobin ; Cognitive Dysfunction/therapy* ; Cholesterol ; gamma-Aminobutyric Acid

BACKGROUND: The hemoglobin glycation index (HGI) was developed to quantify glucose metabolism and individual differences and proved to be a robust measure of individual glycosylated hemoglobin (HbA1c) bias. Here, we aimed to explore the relationship between different HGIs and the risk of 5-year major adverse cardiovascular events (MACEs) by performing a large multicenter cohort study in China. METHODS: A total of 9791 subjects from the Risk Evaluation of Cancers in Chinese Diabetic Individuals: a Longitudinal Study (the REACTION study) were divided into five subgroups (Q1-Q5) with the HGI quantiles (≤5th, >5th and ≤33.3th, >33.3th and ≤66.7th, >66.7th and ≤95th, and >95th percentile). A multivariate logistic regression model constructed by the restricted cubic spline method was used to evaluate the relationship between the HGI and the 5-year MACE risk. Subgroup analysis between the HGI and covariates were explored to detect differences among the five subgroups. RESULTS: The total 5-year MACE rate in the nationwide cohort was 6.87% (673/9791). Restricted cubic spline analysis suggested a U-shaped correlation between the HGI values and MACE risk after adjustment for cardiovascular risk factors ( χ2 = 29.5, P <0.001). After adjustment for potential confounders, subjects with HGIs ≤-0.75 or >0.82 showed odds ratios (ORs) for MACE of 1.471 (95% confidence interval [CI], 1.027-2.069) and 2.222 (95% CI, 1.641-3.026) compared to subjects with HGIs of >-0.75 and ≤-0.20. In the subgroup with non-coronary heart disease, the risk of MACE was significantly higher in subjects with HGIs ≤-0.75 (OR, 1.540 [1.039-2.234]; P = 0.027) and >0.82 (OR, 2.022 [1.392-2.890]; P <0.001) compared to those with HGIs of ≤-0.75 or >0.82 after adjustment for potential confounders. CONCLUSIONS We found a U-shaped correlation between the HGI values and the risk of 5-year MACE. Both low and high HGIs were associated with an increased risk of MACE. Therefore, the HGI may predict the 5-year MACE risk.
Humans ; Cohort Studies ; Longitudinal Studies ; Diabetes Mellitus, Type 2/diagnosis* ; Maillard Reaction ; Glycated Hemoglobin ; Cardiovascular Diseases

Objective: To investigate the predictive value of glycosylated hemoglobin A1c/apolipoprotein A-1 (HbA1c/ApoA-1) ratio for major adverse cardiovascular events (MACEs) in patients with acute coronary syndrome (ACS). Methods: The present study is a retrospective cohort study. ACS patients who were hospitalized and underwent coronary angiography at Beijing Hospital from March 2017 to March 2019 were enrolled. Baseline information such as sex, age, previous history, Gensini score, HbA1c and ApoA-1 were analyzed. Patients were divided into two groups according to presence or absence of MACEs and the difference on HbA1c/ApoA-1 ratio was compared between the two groups. According to the tertiles of HbA1c/ApoA-1 levels, patients were divided into high (5.87-16.12), medium (4.50-5.83) and low (2.11-4.48) HbA1c/ApoA-1 groups. Cox proportional risk model was used to evaluate the differences in MACEs and all-cause mortality among the three groups. Kaplan-Meier survival analysis was used to compare the differences of MACEs between the various HbA1c/ApoA-1 groups. Results: A total of 366 ACS patients were included in this study. The mean age of the patients was (65.9±10.3) years. There were 59 MACEs and 10 all-cause deaths during the mean of (22.3±4.4) months follow-up. After adjusting for age, systolic blood pressure, history of diabetes and Gensini score, the incidence of MACEs was 2.45 times higher in the high HbA1c/ApoA-1 group than in the low HbA1c/ApoA-1 group (95%CI 1.16-5.18, P=0.019). There was no significant difference in all-cause mortality between the high and low HbA1c/ApoA-1 groups (P=1.000). Kaplan-Meier survival analysis showed that patients in the high HbA1c/ApoA-1 group had the highest risk of MACEs, while patients in the low HbA1c/ApoA-1 group had the lowest risk of MACEs (P<0.01). Spearman rank correlation analysis showed that HbA1/ApoA-1 ratio was positively correlated with Gensini score in ACS patients (r=0.274, P<0.01). Conclusion: High HbA1c/ApoA-1 ratio was an independent risk factor for MACEs in ACS patients. Patients with high HbA1c/ApoA-1 ratio had more severe coronary artery disease lesions. HbA1c/ApoA-1 ratio may be used as a potential risk stratification biomarker for ACS patients, it might be useful for the early identification of high-risk population and for predicting the incidence of MACEs among ACS patients.
Aged ; Humans ; Middle Aged ; Acute Coronary Syndrome/diagnosis* ; Apolipoprotein A-I/analysis* ; Biomarkers/analysis* ; Glycated Hemoglobin/analysis* ; Percutaneous Coronary Intervention ; Retrospective Studies ; Risk Factors ; Predictive Value of Tests

Objective: To explore the associations of glycated hemoglobin (HbA1c) with FPG and oral glucose tolerance test 2-hour (OGTT-2 h) in areas at different altitude in China. Methods: Subjects who participated in 2018-2019 China Chronic Disease and Risk Factor Surveillance and had no prior type 2 diabetes diagnosis were included. Subsequently, they were categorized into three groups based on altitude of living area (<2 000, 2 000- and ≥3 000 m). With adjustment for intracluster correlation, multivariable linear regression analysis was performed to evaluate the associations of HbA1c with FPG and OGTT-2 h in the context of HbA1c was normal (<5.7%) or abnormal (≥5.7%). Furthermore, the shape of relationships between HbA1c and glucose indicators was examined using restricted cubic spline. Finally, receiver operating characteristic curve was used to evaluate the diagnostic performance of HbA1c for diabetes. Results: A total of 157 277 subjects were included in the analysis. While FPG and OGTT-2 h levels gradually decreased with increase of altitude, HbA1c level was similar among the three groups. When HbA1c was <5.7%, its association with FPG and OGTT-2 h was weak and no obvious difference was observed among the three groups. When HbA1c was ≥5.7%, the FPG and OGTT-2 h increased by 15.45% (95%CI:14.71%- 16.18%) and 24.54% (95%CI:23.18%-25.91%) respectively per one standard deviation increase in HbA1c in group in area at altitude <2 000 m. However, the FPG and OGTT-2 h increased by 13.08% (95%CI:10.46%-15.76%) and 21.72% (95%CI:16.39%-27.31%), respectively, in group in area at altitude 2 000- m, and increased by 11.41% (95%CI:9.32%-13.53%) and 20.03% (95%CI:15.38%- 24.86%), respectively, in group of altitude ≥3 000 m. The restricted cubic spline indicated that the curve showing the association of HbA1c with FPG and OGTT-2 h was flat when HbA1c was <5.7%, but showed a positive linear relationship when HbA1c was ≥5.7%. The area under curve for detecting diabetes was 0.808 (95%CI:0.803-0.812) in group of altitude <2 000 m and 0.728 (95%CI:0.660-0.796, P=0.022) in group of altitude ≥3 000 m. The relevant optimal cutoff value of HbA1c was 5.7%, with a sensitivity of 65.4% and a specificity of 83.0%, and 6.0%, with a sensitivity of 48.3% and a specificity of 93.7%, respectively. Conclusions: When HbA1c was ≥5.7%, the association between HbA1c and glucose indicators became weaker as the increase of altitude. In the area at altitude ≥3 000 m, it may not be appropriate to use HbA1c in the diagnosis of diabetes.
Adult ; Humans ; Glycated Hemoglobin ; Diabetes Mellitus, Type 2/diagnosis* ; Blood Glucose/analysis* ; Glucose ; Altitude ; Fasting ; China/epidemiology* ; Diabetes Mellitus/epidemiology*