Using Hemoglobin A1C as a Predicting Model for Time Interval from Pre-Diabetes Progressing to Diabetes

Objective

The early identification of subjects at high risk for diabetes is essential, thus, random rather than fasting plasma glucose is more useful. We aim to evaluate the time interval between pre-diabetes to diabetes with anti-diabetic drugs by using HbA1C as a diagnostic tool, and predicting it using a mathematic model.

Methods

We used the Taipei Medical University Affiliated Hospital Patient Profile Database (AHPPD) from January-2007 to June-2011. The patients who progressed and were prescribed anti-diabetic drugs were selected from AHPPD. The mathematical model used to predict the time interval of HbA1C value ranged from 5.7% to 6.5% for diabetes progression.

Results

We predicted an average overall time interval for all participants in between 5.7% to 6.5% during a total of 907 days (standard error, 103 days). For each group found among 5.7% to 6.5% we determined 1169.3 days for the low risk group (i.e. 3.2 years), 1080.5 days (i.e. 2.96 years) for the increased risk group and 729.4 days (i.e. 1.99 years) for the diabetes group. This indicates the patients will take an average of 2.49 years to reach 6.5%.

Conclusion

This prediction model is very useful to help prioritize the diagnosis at an early stage for targeting individuals with risk of diabetes. Using patients'' HbA1C before anti-diabetes drugs are used we predicted the time interval from pre-diabetes progression to diabetes is 2.49 years without any influence of age and gender. Additional studies are needed to support this model for a long term prediction.     

Endo Echo Improves Primary Care Provider And Community Health Worker Self-Efficacy In Complex Diabetes Management In Medically Underserved Communities

Objective: To determine whether participation in a multidisciplinary telementorship model of healthcare delivery improves primary care provider (PCP) and community health worker (CHW) confidence in managing patients with complex diabetes in medically underserved regions.Methods: We applied a well-established healthcare delivery model, Project ECHO (Extension for Community Healthcare Outcomes), to the management of complex diabetes (Endo ECHO) in medically underserved communities. A multidisciplinary team at Project ECHO connected with PCPs and CHWs at 10 health centers across New Mexico for weekly videoconferencing virtual clinics. Participating PCPs and CHWs presented de-identified patients and received best practice guidance and mentor-ship from Project ECHO specialists and network peers. A robust curriculum was developed around clinical practice guidelines and presented by weekly didactics over the ECHO network. After 2 years of participation in Endo ECHO, PCPs and CHWs completed self-efficacy surveys comparing confidence in complex diabetes management to baseline.Results: PCPs and CHWs in rural New Mexico reported significant improvement in self-efficacy in all measures of complex diabetes management, including PCP ability to serve as a local resource for other healthcare providers seeking assistance in diabetes care. Overall self-efficacy improved by 130% in CHWs (P<.0001) and by 60% in PCPs (P<.0001), with an overall large Cohen's effect size.Conclusion: Among PCPs and CHWS in rural, medically underserved communities, participation in Endo ECHO for 2 years significantly improved confidence in complex diabetes management. Application of the ECHO model to complex diabetes care may be useful in resource-poor communities with limited access to diabetes specialist services.Abbreviations: CHW = community health worker; CME = Continuing Medical Education; ECHO = Extension for Community Healthcare Outcomes; FQHC = federally qualified health center; PCP = primary care provider     

Sglt-2 Inhibitors As Adjunct Therapy In Type 1 Diabetes: Reason For Hope And Caution

Abbreviations:CGM = continuous glucose monitoringDCGM = Dexcom G4 Platinum CGMDKA = diabetic ketoacidosisDM = diabetes mellitusHbA1c = glycated hemoglobin A1cSGLT-2 = sodium glucose cotransporter 2     

Hemoglobin A1C Criterion for Diabetes Diagnosis Among Hispanic and Non-Hispanic Populations

ObjectiveTo report on the performance of the recently recommended hemoglobin A1c (A1C) criterion for diabetes diagnosis in comparison with the standard fasting plasma glucose and 2-hour post-glucose challenge (PG) test criteria across racial and ethnic groups.MethodsWe evaluated local and national survey data from 689 Dominican, 4, 862 Hispanic, 4, 694 African American, and 6, 883 white study subjects. We compared rates of diabetes classification by diagnostic criteria, agreement and disagreement between A1C and PG criteria for diagnosing diabetes, and differences in cardiometabolic risk among the 3 diagnostic groups across racial and ethnic stratifications.ResultsThe A1C-based diabetes diagnoses were higher among Dominican and African American study subjects (81.6% and 67.0%, respectively), and lower among Hispanic and white subjects (46.0% and 37.9%, respectively). Among those not meeting any PG criterion for diabetes, the A1C criterion identified diabetes in 8.3% of Dominican, 3.5% of African American, 0.9% of Hispanic, and 0.5% of white study subjects. The A1C criterion, however, did not identify diabetes in 64.5% of white, 46.1% of Dominican, 44.0% of African American, and 41.9% of Hispanic subjects who were diagnosed with diabetes by a PG criterion. For single tests, the agreement was greatest between A1C and fasting plasma glucose test criteria among Dominican, Hispanic, and African American study populations—76.9%, 65.6%, and 60.7%, respectively. There was no clear difference in selected cardiometabolic risks between A1C and PG-only diabetes diagnoses across racial and ethnic groups.ConclusionThe A1C criterion yields racialand ethnic-specific differences in diagnosing diabetes and in test agreements with PG-based criteria. Furthermore, diagnostic differences were observed between the Dominican subgroup and the Hispanic study population, of whom 91.5% were Mexican American. (Endocr Pract. 2011;17: 210-217)     

Frequency of Continuous Glucose Monitoring use and Change in Hemoglobin A1C for Adults With Type 1 Diabetes in a Clinical Practice Setting

ObjectiveTo estimate the frequency of continuous glucose monitoring (CGM) use and change in hemoglobin A1c (HbA1c) compared to self-monitoring of blood glucose (SMBG) alone in adults with type 1 diabetes in a clinical practice setting.MethodsWe retrospectively identified 66 adult type 1 diabetes patients at the Barbara Davis Center for Diabetes (BDC) who first initiated CGM between 2006 and 2011 and 67 controls using SMBG. The frequency of CGM use was estimated from survey recall and defined as the mean number of days/month of CGM use during a maximum follow-up of 10 months. Change in HbA1c was calculated as the difference between the baseline value and the lowest follow-up value.ResultsThe mean change in HbA1c for CGM users was − 0.48% (95% confidence interval [CI]: − 0.67, − 0.28) and for SMBG users was − 0.37% (95% CI: − 0.56, − 0.18). The between-group mean difference in change in HbA1c, adjusted for patient characteristics, was − 0.11% (95% CI: − 0.38, 0.16), whereas the subgroup with a baseline HbA1c ≥ 7.0% and users of CGM ≥ 21 days/month was − 0.36% (95% CI, − 0.78, 0.05). Nearly half (n = 32, 48%) used CGM < 21 days/month. The reasons for low frequency of CGM use or discontinuation included sensor costs, frequency of alarms, inaccuracy, and discomfort.ConclusionsThese CGM data from clinical practice suggest a trend toward decreasing HbA1c for adults with type 1 diabetes, especially in patients with higher baseline HbA1c and higher frequency of CGM use. Future studies are needed to assess the use of CGM in larger populations of clinical practice adult type 1 diabetes patients. (Endocr Pract. 2014;20:1007-1015)     

Performance of A1C Versus Ogtt for the Diagnosis of Prediabetes in a Community-Based Screening

Objective: Reliable identification of individuals at risk for developing diabetes is critical to instituting preventative strategies. Studies suggest that the accuracy of using hemoglobin A1c as a sole diagnostic criterion for diabetes may be variable across different ethnic groups. We postulate that there will be lack of concordance between A1c and the oral glucose tolerance test (OGTT) for diagnosing prediabetes across Hispanic and non-Hispanic white (NHW) populations.Methods: A total of 218 asymptomatic adults at risk for type 2 diabetes (T2D) were assessed with A1c and OGTT for the diagnosis of prediabetes. Glucose homeostasis status was assigned as no diabetes (A1c <5.7% [39 mmol/mol]), prediabetes (A1c 5.7 to 6.4% [46 mmol/mol]), and T2D (A1c >6.4% [46 mmol/mol]). Inclusion criteria were age >18 years and at least one of the following: a family history of diabetes, a history of gestational diabetes, Hispanic ethnicity, non-Caucasian race, or obesity. Subjects received a fasting 75-g OGTT and A1c on the same day. Bowker's test of symmetry was employed to determine agreement between the tests.Results: Data from 99 Hispanic patients and 79 NHW patients were analyzed. There was no concordance between A1c and OGTT for Hispanic (P =.002) or NHW individuals (P =.003) with prediabetes.Conclusion: A1c is discordant with OGTT among Hispanic and NHW subjects for the diagnosis of prediabetes. Sole use of A1c to designate glycemic status will result in a greater prevalence of prediabetes among Hispanic and NHW New Mexicans.Abbreviations:A1c = hemoglobin A1cBMI = body mass indexCDC = Centers for Disease ControlCI = confidence intervalFPG = fasting plasma glucoseNHW = non-Hispanic whiteOGTT = oral glucose tolerance testT2D = type 2 diabetesWHO = World Health Organization     

Hemoglobin A1C,Mean Glucose,and Persistence of Glycation Ratios in Insulin-Treated Diabetes

ObjectiveDetermine the relationship between mean glucose (MG), as assessed by continuous glucose monitoring (CGM), and hemoglobin A_1c (A1C) in insulin-requiring adults in a clinical practice setting and examine the persistence of this relationship over time.MethodsIn this retrospective record review in a diabetes practice, a linear regression model was developed using data sets from all patients with ≥ 1 available download of a Dexcom SevenPlus CGM device in which there was > 50% utilization in the 60 days prior to a laboratory A1C. Persistence of the MG to A1C relationship was examined in patients with ≥ 2 data sets available.ResultsA total of 139 patients had ≥ 1 data set available for evaluation, and 101 patients had ≥ 2 data sets (range, 2 to 6; total, 279). The slope of the MG versus A1C curve was 19.5 mg/dL for each 1% change in A1C, with an intercept of 17.7 mg/dL. Although 88% of the measured MG values were within 15% of the A1C-predicted MG, there was substantial variation in individuals, with differences as large as ± 26%. The MG to A1C (MG:A1C) ratio, which is a measure of glycation, was normally distributed, with a median of 21.6. Spearman correlation coefficients for the MG:A1C ratio on repeated measures ranged from 0.52 to 0.73, demonstrating persistence.ConclusionThe relationship between MG and A1C is linear in a population but can vary between individuals. The MG:A1C ratio was normally distributed, tended to persist in individuals over time, and thus could be useful to identify apparent high and low glycators. Glycemic goals may need to be modified in such patients. (Endocr Pract. 2014;20:252-260)     

Hba1C Control And Cost-Effectiveness in Patients With Type 2 Diabetes Mellitus Initiated On Canagliflozin or A Glucagon-Like Peptide 1 Receptor Agonist in A Real-World Setting

Objective: To compare glycated hemoglobin (HbA1c) control and medication costs between patients with type 2 diabetes mellitus (T2DM) treated with canagliflozin 300 mg (CANA) or a glucagon-like peptide 1 receptor agonist (GLP-1 RA) in a real-world setting.Methods: Adults with T2DM newly initiated on CANA or a GLP-1 RA (index date) were identified from IQVIA™ Real-World Data Electronic Medical Records U.S. database (March 29, 2012–April 30, 2016). Inverse probability of treatment weighting accounted for differences in baseline characteristics. HbA1c levels at 3-month intervals were compared using generalized estimating equations. Medication costs used wholesale acquisition costs.Results: For both cohorts (CANA: n = 11,435; GLP-1 RA: n = 11,582), HbA1c levels decreased at 3 months postindex and remained lower through 30 months. Absolute changes in mean HbA1c from index to 3 months postindex for CANA and GLP-1 RA were -1.16% and -1.21% (patients with baseline HbA1c ≥7% &lsqb;53 mmol/mol]); -1.54% and -1.51% (patients with baseline HbA1c ≥8% &lsqb;64 mmol/mol]); and -2.13% and -1.99% (patients with baseline HbA1c ≥9% &lsqb;75 mmol/mol]), respectively. Postindex, CANA patients with baseline HbA1c ≥7% had similar HbA1c levels at each interval versus GLP-1 RA patients, except 9 months (mean HbA1c, 7.75% &lsqb;61 mmol/mol] vs. 7.86% &lsqb;62 mmol/mol]; P = .0305). CANA patients with baseline HbA1c ≥8% and ≥9% had consistently lower HbA1c numerically versus GLP-1 RA patients and statistically lower HbA1c at 9 (baseline HbA1c ≥8% or ≥9%), 27, and 30 months (baseline HbA1c ≥9%). Continuous 12-month medication cost $3,326 less for CANA versus GLP-1 RA.Conclusion: This retrospective study demonstrated a similar evolution of HbA1c levels among CANA and GLP-1 RA patients in a real-world setting. Lower medication costs suggest CANA is economically dominant over GLP-1 RA (similar effectiveness, lower cost).Abbreviations:AHA = antihyperglycemic agentBMI = body mass indexCANA = canagliflozin 300 mgDCSI = diabetes complications severity indexeGFR = estimated glomerular filtration rateEMR = electronic medical recordGLP-1 RA = glucagon-like peptide 1 receptor agonistHbA1c = glycated hemoglobinICD-9-CM = International Classification of Diseases–Ninth Revision–Clinical ModificationICD-10-CM = International Classification of Diseases–Tenth Revision–Clinical ModificationIPTW = inverse probability of treatment weightingITT = intent-to-treatMPR = medication possession ratioPDC = proportion of days coveredPS = propensity scorePSM = propensity score matchingQuan-CCI = Quan-Charlson comorbidity indexSGLT2 = sodium-glucose cotransporter 2T2DM = type 2 diabetes mellitusWAC = wholesale acquisition cost     

Value of Hemoglobin A1C In Diagnosing Diabetes Mellitus within a Chronic Disease Management System Illustrated by the Receiver Operating Characteristic Curve

ObjectiveTo develop a receiver operating characteristic (ROC) curve of glycosylated hemoglobin (HbA_1c) for diagnosing diabetes mellitus within a chronic disease management system.MethodsA case-control study including medical records from January 1, 1997, to December 31, 2005, was conducted at the Sioux Falls Veterans Affairs Medical Center. Medical records for the case group (patients with diabetes) were selected based on 1 of 3 criteria: International Classification of Diseases, Ninth Revision, Clinical Modification or Current Procedural Terminology codes specific for type 1 and type 2 diabetes; patients’ use of medications (oral hypoglycemic agents, antidiabetes agents, or insulin); or results from random blood or plasma glucose tests (at least 2 measurements of blood glucose ≥ 200 mg/dL). Records for the control group were selected based on patients having HbA_1c measured, but not meeting the above diagnostic criteria for diabetes during the study period. Records for cases and controls were randomly frequency-matched, one-to-one. The control group was randomly divided into 5 sets of an equal number of records. Five sets of an equal number of cases were then randomly selected from the total number of cases. Each test data set included 1 case group and 1 control group, resulting in 5 independent data sets.ResultsIn total, 5040 patient records met the case definition in the diabetes registry. Records of 15 patients who were prescribed metformin only, but did not meet any other case criteria, were reviewed and excluded after determining the patients were not diabetic. The control group consisted of 5 sets of 616 records each (totaling 3080 records), and the case group consisted of 5 sets of 616 records each (totaling 3080 records). Thus, each of the 5 independent data sets of 1 case group and 1 control group contained 1232 records. The case group was predominantly composed of white men (mean age, 69 years; mean body mass index, 31 kg/m²). Demographic data were similar for control patients. The ROC curve revealed that a HbA_1c ≥ 6.3% (mean + 1 SD) offered the most accurate cutoff value for diagnosing type 2 diabetes mellitus, with the following statistical values: C statistic, 0.78; sensitivity, 70%; specificity, 85%; and positive likelihood ratio, 4.6 (95% confidence interval, 4.2-5.0).ConclusionA HbA_1c value ≥ 6.3% may be a useful benchmark for diagnosing diabetes mellitus within a chronic disease management system and may be a useful tool for monitoring high-risk populations. (Endocr Pract. 2010;16:14-20)     

A Qualitative Model For Inundation Studies In Archeological Research And Resource Conservation:An Example From Arkansas

Abstract

Federal and state flood control and water resource management projects are exposing an ever increasing number of archeological sites to long term inundation in reservoirs. The effectsof this inundation on the submerged archeological context is not well understood, handicapping the archeologists in their attempts to mitigate the effects of these projects on this portion of the cultural resource base as required by recent federal legislation. This paper pointsout the inadequacy of our present knowledge, cites the need for research, and proposes a model as a basis for research into the. effects of inundation on archeological sites.     

The Uptake of Screening for Type 2 Diabetes and Prediabetes by Means of Glycated Hemoglobin versus the Oral Glucose Tolerance Test among 18 to 60-Year-Old People of South Asian Origin: A Comparative Study

Background

Direct comparisons of the effect of a glycated haemoglobin measurement or an oral glucose tolerance test on the uptake and yield of screening in people of South Asian origin have not been made. We evaluated this in 18 to 60-year-old South Asian Surinamese.

Materials and Methods

We invited 3173 South Asian Surinamese for an oral glucose tolerance test between June 18^th 2009- December 31^st 2009 and 2012 for a glycated hemoglobin measurement between April 19^th 2010-November 11^th, 2010. Participants were selected from 48 general practices in The Hague, The Netherlands. We used mixed models regression to analyse differences in response and participation between the groups. We described differences in characteristics of participants and calculated the yield as the percentage of all cases identified, if all invitees had been offered screening with the specified method.

Results

The response and participation in the glycated hemoglobin group was higher than in the group offered an oral glucose tolerance test (participation 23.9 vs. 19.3; OR: 1.30, 95%-confidence interval1.01–1.69). After adjustment for age and sex, characteristics of participants were similar for both groups. Overall, glycated hemoglobin identified a similar percentage of type 2 diabetes cases but a higher percentage of prediabetes cases, in the population than the oral glucose tolerance test.

Conclusion

We found that glycated hemoglobin and the oral glucose tolerance test may be equally efficient for identification of type 2 diabetes in populations of South Asian origin. However, for programs aimed at identifying people at high risk of type 2 diabetes (i.e. with prediabetes), the oral glucose tolerance test may be a less efficient choice than glycated hemoglobin.     

Concordance of Two Diabetes Diagnostic Criteria Using Fasting Plasma Glucose and Hemoglobin A1c: The Yuport Medical Checkup Centre Study

Background

We tested the concordance of the two diagnostic criteria for diabetes using fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c) by the Japan Diabetes Society (JDS) and American Diabetes Association (ADA).

Methods

We used data from 7,328 subjects without known diabetes who participated in a voluntary health checkup program at least twice between 1998 and 2006, at intervals ≤2 years. For repeat participants who attended the screening over two times, data from the first and second checkups were used for this study. At the first visit, diabetes was diagnosed both at FPG ≥7.0 mmol/L and HbA1c ≥6.5% using the JDS criteria. In addition, diabetes was diagnosed using two ADA criteria; ADA-FPG diabetes for persistent fasting hyperglycemia (FPG ≥7.0 mmol/L) or ADA-HbA1c diabetes for hyper-glycated hemoglominemia (HbA1c ≥6.5%), both at the first and second checkups. Subsequently, the concordance of diagnosis between the JDS and the ADA criteria was evaluated.

Results

At the first checkup, 153 (2.1%) persons were diagnosed with diabetes by the JDS criteria. They had higher levels of risk factors for diabetes than non-diabetic subjects. Using the first and second checkups, 174 (2.4%) and 175 (2.4%) were diagnosed with diabetes by the ADA-FPG criteria, respectively. Among 153 subjects diagnosed with diabetes by the JDS criteria, 125 (81.7%) and 129 (84.3%) had ADA-FPG and ADA-HbA1c diabetes, respectively. The kappa coefficients of the JDS criteria with ADA-FPG and ADA-HbA1c criteria were 0.759 and 0.782 (P<0.001), respectively. In the subgroup analysis stratified by sex, the concordance was well preserved at the kappa coefficients around 0.8 (between 0.725 and 0.836).

Conclusion

The JDS diagnostic criteria for diabetes have a substantial and acceptable concordance with the ADA criteria. The JDS criteria may be a practical method for diagnosing diabetes that maintains compatibility with the ADA criteria.     

Effect of Baseline Glycosylated Hemoglobin A1C on Glycemic Control and Diabetes Management following Initiation of Once-daily Insulin Detemir in Real-Life Clinical Practice

ObjectiveThe SOLVE study investigated the initiation of basal insulin in patients with type 2 diabetes on oral antidiabetic (OAD) treatment and outcomes in patients with varying levels of glycemic control at baseline.MethodsThis was an observational cohort study conducted in 10 countries using insulin detemir. Data were collected at 3 clinic visits (baseline, 12-week interim, and 24-week final visit).ResultsA total of 13,526 (77.9%) patients were included in the glycosylated hemoglobin A1c (HbA1c) subset analysis. Patients were grouped according to pre-insulin HbA1c values as follows: HbA1c <7.6% (n = 2,797); HbA1c 7.6-9% (n = 5,366), and HbA1c >9% (n = 5,363). A total of 27 patients experienced serious adverse drug reactions (SADRs) and/or severe hypoglycemia (3, 10, and 11 patients with pre-insulin HbA1c <7.6%, 7.6-9.0%, and >9.0%, respectively). All patient subgroups realized improvements in HbA1c, with the pre-insulin HbA1c >9% subgroup having the largest HbA1c reduction (-2.4% versus -0.9% and -0.2% for HbA1c subgroups 7.6-9% and <7.6%, respectively). In the total cohort (n = 17,374), the incidence of severe hypoglycemia decreased from 4 events per 100 person years to <1 event per 100 person years by final visit; the incidence of minor hypoglycemia increased from 1.6 to 1.8 events per person year.ConclusionsIn this study, insulin initiation was delayed until late in disease course, and overall concordance with internationally recognized guidelines was low. The initiation of once-daily insulin detemir was associated with substantial improvements in glycemic control and was not associated with an increase in severe hypoglycemia or weight gain. (Endocr Pract. 2013;19:462-470)     

Sex-Specific Associations of Iron-Anemia Status With Hemoglobin A1C Levels Among Hispanics/Latinos Without Self-Reported Diabetes Mellitus: The Hispanic Community Health Study/Study of Latinos

ObjectiveThe objective of this study was to examine the sex-specific associations of mutually exclusive iron-anemia status categories with hemoglobin A1C (HbA1C) levels among U.S. Hispanics/Latinos without self-reported diabetes mellitus.MethodsBaseline cross-sectional data (7247 women and 4904 men without self-reported diabetes mellitus) from the Hispanic Community Health Study/Study of Latinos were analyzed. Per the American Diabetes Association’s defined criteria, based on HbA1C levels, the participants were categorized as having normoglycemia, prediabetes, or probable diabetes mellitus. The iron-anemia status categories were as follows: no anemia and no iron deficiency (reference), iron deficiency, iron deficiency anemia (IDA), and non-iron deficiency anemia (non-IDA). Survey multinomial logistic regression models were used to examine the sex-specific associations of iron-anemia status with HbA1C levels after adjusting for sociodemographic, lifestyle, and clinical factors.ResultsThe age-standardized prevalence of iron-anemia status categories differed by sex. Compared with those with no anemia and no iron deficiency and normoglycemia, women with IDA had higher odds of having prediabetes (odds ratio [OR], 2.18; 95% CI, 1.64-2.89) and probable diabetes mellitus (OR, 3.59; 95% CI, 1.62-7.99) based on HbA1C levels; men with non-IDA had higher odds of having probable diabetes mellitus (OR, 2.97; 95% CI, 1.13-7.78) based on HbA1C levels. All other associations did not reach statistical significance.ConclusionAmong U.S. Hispanics/Latinos without self-reported diabetes mellitus, the age-standardized prevalence of iron deficiency, IDA, and non-IDA is high and varies by sex. Women with IDA had higher odds of having prediabetes and probable diabetes mellitus, defined based on HbA1C levels. Men with non-IDA had higher odds of having probable diabetes mellitus, defined based on HbA1C levels. Iron-anemia status should be considered while interpreting elevated HbA1C levels among U.S. Hispanics/Latinos without self-reported diabetes mellitus.