Related Experiment Video
Updated: Jan 20, 2026
Tear-Derived Exosomal miR-15a as New Diagnostic Tool for Diabetic Retinopathy
Published on: December 30, 2025
HbA1c level as a risk factor for retinopathy and nephropathy in children and adults with type 1 diabetes: Swedish
Marcus Lind1,2, Aldina Pivodic3, Ann-Marie Svensson4,5
1Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden lind.marcus@telia.com.
Insights
Achieving glycated hemoglobin (HbA1c) below 6.5% in type 1 diabetes did not lower retinopathy or nephropathy risks compared to 6.5-6.9%, but increased severe hypoglycemia risk. Higher HbA1c levels (>7.0%) elevated risks for milder complications.
Area of Science:
- Endocrinology
- Diabetology
- Ophthalmology
- Nephrology
Background:
- Type 1 diabetes management aims to prevent long-term microvascular complications.
- Glycemic control, measured by HbA1c, is crucial for mitigating these risks.
- The optimal HbA1c target for preventing retinopathy and nephropathy in type 1 diabetes remains debated.
Purpose of the Study:
- To assess if a strict glycated hemoglobin (HbA1c) target of <6.5% reduces retinopathy and nephropathy risk in type 1 diabetes.
- To compare the risks associated with HbA1c <6.5% versus less stringent control (6.5-6.9%).
Main Methods:
- A population-based cohort study utilizing the Swedish National Diabetes Registry (1998-2017).
- Inclusion of 10,398 individuals with type 1 diabetes, followed from diagnosis.
- Analysis of relative risks (odds ratios) for retinopathy and nephropathy across different mean HbA1c levels, adjusted for multiple covariates.
Main Results:
- No significant difference in retinopathy or nephropathy risk was observed between HbA1c <6.5% and HbA1c 6.5-6.9%.
- Increased risk for severe hypoglycemia was noted with HbA1c <6.5% compared to 6.5-6.9%.
- Elevated risks for milder retinopathy and nephropathy complications began at HbA1c levels >7.0%, with severe complications increasing significantly at HbA1c >8.6%.
Conclusions:
- A target HbA1c of <6.5% does not offer additional protection against retinopathy and nephropathy compared to 6.5-6.9% in type 1 diabetes.
- The primary risk for severe microvascular complications in type 1 diabetes emerges at higher HbA1c levels (>8.6%).
- Less stringent glycemic control targets (HbA1c 6.5-6.9%) may be considered to avoid increased hypoglycemia risk without compromising protection against major retinopathy and nephropathy.
Objective:
To evaluate if the lowest target level for glycated haemoglobin (HbA1c) of <6.5% is associated with lower risk for retinopathy and nephropathy than less tight control in children and adults with type 1 diabetes.
Design:
Population based cohort study.
Setting:
Swedish National Diabetes Registry, 1 January 1998 to 31 December 2017.
Participants:
10 398 children and adults with type 1 diabetes followed from diagnosis, or close thereafter, until end of 2017.
Main Outcome Measures:
Relative risk (odds ratios) for retinopathy and nephropathy for different mean levels of HbA1c.
Results:
Mean age of participants was 14.7 years (43.4% female), mean duration of diabetes was 1.3 years, and mean HbA1c level was 8.0% (63.4 mmol/mol). After adjustment for age, sex, duration of diabetes, blood pressure, blood lipid levels, body mass index, and smoking, the odds ratio for mean HbA1c <6.5% (<48 mmol/mol) compared with 6.5-6.9% (48-52 mmol/mol) for any retinopathy (simplex or worse) was 0.77 (95% confidence interval 0.56 to 1.05, P=0.10), for preproliferative diabetic retinopathy or worse was 3.29 (0.99 to 10.96, P=0.05), for proliferative diabetic retinopathy was 2.48 (0.71 to 8.62, P=0.15), for microalbuminuria or worse was 0.98 (0.60 to 1.61, P=0.95), and for macroalbuminuria was 2.47 (0.69 to 8.87, P=0.17). Compared with HbA1c levels 6.5-6.9%, HbA1c levels 7.0-7.4% (53-57 mmol/mol) were associated with an increased risk of any retinopathy (1.31, 1.05 to 1.64, P=0.02) and microalbuminuria (1.55, 1.03 to 2.32, P=0.03). The risk for proliferative retinopathy (5.98, 2.10 to 17.06, P<0.001) and macroalbuminuria (3.43, 1.14 to 10.26, P=0.03) increased at HbA1c levels >8.6% (>70 mmol/mol). The risk for severe hypoglycaemia was increased at mean HbA1c <6.5% compared with 6.5-6.9% (relative risk 1.34, 95% confidence interval 1.09 to 1.64, P=0.005).
Conclusions:
Risk of retinopathy and nephropathy did not differ at HbA1c levels <6.5% but increased for severe hypoglycaemia compared with HbA1c levels 6.5-6.9%. The risk for severe complications mainly occurred at HbA1c levels >8.6%, but for milder complications was increased at HbA1c levels >7.0%.
More Related Videos
08:15Author Spotlight: Network Pharmacology and Molecular Docking to Decipher the Action of Jiawei Shengjiang San Against Diabetic Kidney Disease
Published on: May 10, 2024
10:11Fundus Photography as a Convenient Tool to Study Microvascular Responses to Cardiovascular Disease Risk Factors in Epidemiological Studies
Published on: October 22, 2014
Related Concept Videos
07:45Tear-Derived Exosomal miR-15a as New Diagnostic Tool for Diabetic Retinopathy
08:15Antagonistic Effect of Jiawei Shengjiang San on a Rat Model of Diabetic Nephropathy: Related to EGFR/MAPK3/1 Signaling Pathway
10:11Fundus Photography as a Convenient Tool to Study Microvascular Responses to Cardiovascular Disease Risk Factors in Epidemiological Studies
06:50A High-Throughput Electrochemiluminescence 7-Plex Assay Simultaneously Screening for Type 1 Diabetes and Multiple Autoimmune Diseases
06:46A High-Throughput Multiplexed Screening for Type 1 Diabetes, Celiac Diseases, and COVID-19
04:26Streptozocin Treatment: A Zebrafish Model of Type 1 Diabetes Mellitus