glycated Hb (HbA1C)

Overview

Glycated hemoglobin, commonly reported as HbA1c, is a clinical metric that reflects the proportion of hemoglobin that has undergone nonenzymatic glycation by circulating glucose. Because red blood cells circulate for roughly 2–3 months, HbA1c provides an integrated estimate of average glycemic exposure over preceding weeks to months rather than a single time point. It is therefore widely used in diabetes diagnosis, monitoring, and risk stratification, including assessment of prediabetes, overt diabetes, and long-term glycemic control.

Clinically, HbA1c is central to evaluating metabolic status in type 1 diabetes, type 2 diabetes, obesity-associated insulin resistance, and related Cardiometabolic comorbidity. It is also used alongside other markers such as fasting plasma glucose, glucose tolerance test results, continuous glucose monitor metrics, and fructosamine when interpreting glycemia in settings where HbA1c may be insufficient on its own. In recent research, HbA1c has been used both as an outcome measure and as a covariate associated with insulin resistance, diabetic retinopathy, chronic kidney disease, wound outcomes, and broader inflammatory or metabolic phenotypes.

Focus of Latest Publications

Recent studies used HbA1c as both a primary outcome and a contextual biomarker across diverse diabetes-related investigations. In obesity research, a transcriptionally distinct adipocyte population with an end-of-trajectory signature (hEOS) was reported to emerge during obesity and drive maladaptive inflammation; the overall activity of this axis correlated with BMI, HbA1c, and insulin resistance in humans, linking HbA1c to adipose tissue dysfunction and systemic metabolic stress.

Several studies focused on detection and monitoring of dysglycemia. A prospective feasibility study in underserved communities evaluated a community pharmacy pathway using verified point-of-care HbA1c testing to identify prediabetes and facilitate engagement with a digital prevention programme, with the goal of detecting undiagnosed type 2 diabetes. In another study, HbA1c was compared with fasting plasma glucose, 0.5-hour plasma glucose, 1-hour plasma glucose, and 2-hour plasma glucose during an oral glucose tolerance test to determine whether 1-hour plasma glucose better identified early-phase insulin secretory defects in young adults with obesity. These studies reinforce HbA1c’s role as a practical screening and monitoring marker, while also highlighting its limitations for detecting early pathophysiology.

HbA1c was also used as a longitudinal quality metric in diabetes care delivery. In a registry analysis from the Australasian Diabetes Data Network, higher HbA1c after transfer from pediatric to adult type 1 diabetes services was associated with younger age at transfer, indicating that transition timing may influence adult glycemic outcomes. A pilot intervention in emerging adults with type 1 diabetes and above-recommended HbA1c tested a brief values-guided self-management approach aimed at improving glucose levels and increasing the proportion of patients reaching recommended time in range. In a separate retrospective cohort study, endocrinology consultation delivered by electronic consultation, synchronous telemedicine, or in person was evaluated for its association with 6-month HbA1c improvement to below 8% among adults with uncontrolled type 2 diabetes, supporting HbA1c as a standard endpoint for care-model comparisons.

HbA1c was also used in studies of complications and comorbidity. In diabetic retinopathy research, investigators noted that retinopathy can occur despite well-controlled glycemia, defined as HbA1c below 7.0%, suggesting that glycation-related factors beyond HbA1c may contribute to disease development. In a cohort of frail older adults, routinely collected HbA1c testing data were examined in relation to frailty, emphasizing the marker’s use in geriatric risk profiling. In people with type 2 diabetes and chronic kidney disease, HbA1c was measured alongside fasting lipid profile, fasting plasma glucose, serum creatinine, and glomerular filtration rate estimates derived from CKD-EPI and other equations to assess glycemic control in the context of renal impairment. Another study in people with type 2 diabetes reported HbA1c as part of the laboratory profile associated with chronic kidney disease risk factors such as unfavorable lifestyle, hypertriglyceridemia, and smoking.

HbA1c was further used in surgical and wound-related risk assessment. In diabetic patients undergoing open transversus abdominis release for abdominal wall reconstruction, preoperative glycemic control measured by HbA1c was described as widely used in risk stratification, and long-term wound morbidity and hernia recurrence were examined in those with HbA1c at or above 8.5%. In a study of foot care practices among patients with diabetes mellitus in Sudan, good glycemic control was defined as HbA1c at or below 7%, linking the metric to preventive self-care behavior and complication avoidance.

Beyond observational work, HbA1c served as an efficacy endpoint in therapeutic studies. A pharmacist intervention study evaluated real-time continuous glucose monitors added to pharmacist care and measured glycated hemoglobin changes relative to standard care. A community pharmacy-led pilot feasibility study used continuous glucose monitoring in suboptimally controlled type 2 diabetes and defined success partly by achieving HbA1c at or below 7.0% and a meaningful HbA1c reduction. In a preclinical diabetes therapy study, a conjugated exendin-4 construct with an IgG Fc-binding motif was reported to rival semaglutide in reducing HbA1c and protecting pancreatic islets without toxicity. Another experimental study in rats assessed glycemic and metabolic effects of glycine combined with thymoquinone, including glycated Hb (HbA1C), insulin, HOMA-IR, HOMA %B, and HOMA %S. A separate report noted that denosumab had previously been shown to lower HbA1c in older patients with impaired glucose tolerance, although the cited study itself examined glucose and lipid homeostasis in young infertile men.

HbA1c also appeared in studies of broader disease associations. In ischemic stroke patients with diabetes, higher glucose, HbA1c, and neutrophils were reported in association with diabetic stroke. In a study of cardiometabolic and inflammatory biology, HbA1c was one of the human correlates of an obesity-associated signaling axis involving insulin resistance. Across these contexts, HbA1c functioned as a stable, clinically interpretable marker of chronic glycemic exposure and a common endpoint for evaluating interventions, disease severity, and complication risk.

Key Publications

• NEWMay A transcriptionally distinct population of human adipocytes with end-of-trajectory signature (hEOS) emerges during obesity to drive maladaptive inflammation. (Pharmacological research, 2026, PMID 42107509): "The overall activity of this axis correlates with BMI, HbA1c, and insulin resistance in humans."
• Jul Detection of prediabetes and undiagnosed type 2 diabetes in underserved communities using community pharmacy point-of-care testing: A prospective feasibility study. (Diabetic medicine : a journal of the British Diabetic Association, 2026, PMID 42141696): "We assessed a pharmacy-based pathway using verified point-of-care HbA1c testing to identify prediabetes and enable engagement with a digital prevention programme and established the detection rates for undiagnosed T2D."
• May The 1-hour plasma glucose as a specific marker for early-phase insulin secretory defects in young adults with obesity. (Diabetes research and clinical practice, 2026, PMID 42184890): "To determine whether 1-hour plasma glucose (1-h PG) during an OGTT outperforms other glycemic markers (FPG, 0.5-h PG, 2-h PG, HbA1c) in identifying impairments in insulin secretion, sensitivity, and β-cell compensation."
• Jul Higher HbA1c Following Younger Age of Transfer From Pediatric to Adult Type 1 Diabetes Services: Data From the Australasian Diabetes Data Network (ADDN) Registry. (Diabetes care, 2026, PMID 42207931): "...factors associated with adult service HbA1c."
• Jul Preliminary Outcomes of a Brief Values-Guided Self-Management Intervention to Improve Glucose Levels Among Emerging Adults With Type 1 Diabetes and Above-Recommended HbA1c: A Pilot Study. (Endocrinology, diabetes & metabolism, 2026, PMID 42234497): "A minority of young adults with type 1 diabetes achieve ≥70% time in range (TIR; 70-180 mg/dL [3.9-10 mmol/L]), as recommended."
• Jul Compliance With Foot Care Practices Among Patients With Diabetes Mellitus in Sudan. (International wound journal, 2026, PMID 42380043): "...and good glycemic control (HbA1c ≤7%; p=0.001)."
• Jun Effects of a single-dose denosumab on glucose and lipid homeostasis in young infertile men. (Endocrine, 2026, PMID 42347899): "Denosumab has been shown to lower HbA1c in older patients with impaired glucose tolerance."
• Jun IgG Fc-Binding Motif-Conjugated Exendin-4: A Long-Acting Hypoglycemic Agent via Broad-Spectrum Antibody Engagement for Type 2 Diabetes Therapy. (Bioconjugate chemistry, 2026, PMID 42216891): "Chronic once-daily dosing of the lead conjugate rivaled semaglutide in reducing HbA1c and protecting pancreatic islets, without toxicity."
• Jun Unfavorable lifestyle, hypertriglyceridemia and smoking are risk factors for chronic kidney disease in people with type 2 diabetes. (Nutricion hospitalaria, 2026, PMID 41878915): "Glucose, glycated hemoglobin (HbA1c), and lipid profile were measured in venous blood, and CKD was diagnosed through CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration), MDRD-4 (Modification of Diet in Renal Disease), and Cockcroft-Gault equations."
• Jun Long-term wound morbidity and hernia recurrence in diabetic patients with HbA1c ≥ 8.5% undergoing open transversus abdominis release: a descriptive longitudinal follow-up of a single-center cohort. (Hernia : the journal of hernias and abdominal wall surgery, 2026, PMID 42295428): "Preoperative glycemic control, as measured by HbA1c, is widely used in risk stratification for diabetic patients undergoing abdominal wall reconstruction (AWR)."