How better blood sugar control affects HDL ('good') cholesterol in people with type 1 diabetes

Effect of Improved Glycemic Control on the Composition and Function of High-density Lipoproteins (HDL) in Patients With Type 1 Diabetes: a Prospective, Single-center Study. Comparison With Non-diabetic, Non-dyslipidemic Control Subjects. - HAGI-T1D Study

This project tries to see if better blood sugar control in people with poorly controlled type 1 diabetes improves the makeup and protective function of HDL ('good') cholesterol.

Quick facts

• Study type: Observational
• Enrollment: 143 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Centre Hospitalier Universitaire Dijon (other)
• Locations: 1 site (Dijon)
• Trial ID: NCT07564752 on ClinicalTrials.gov

What this trial studies

This observational study will enroll about 80 adults with type 1 diabetes (HbA1c > 8.0%) admitted to the endocrinology department at CHU Dijon Bourgogne for intensified glycemic management, plus about 63 non-diabetic, non-dyslipidemic control participants. T1D participants will receive intensified therapy according to standard clinical practice (insulin adjustments, therapeutic education, and lifestyle/diet guidance) while blood and urine samples are collected to create a plasma/serum biobank. Laboratory analyses will examine HDL composition and functional assays to determine whether improved glycemic control restores anti-atherogenic HDL properties. Results in the T1D group will be compared to the control group using serial samples collected before and after glycemic improvement.

Who should consider this trial

Good fit: Ideal candidates are adults with treated type 1 diabetes and HbA1c > 8.0% who can be hospitalized at CHU Dijon Bourgogne for intensified management, and healthy non-diabetic adults who meet the specified fasting glucose and lipid criteria for the control group.

Not a fit: People without poorly controlled type 1 diabetes, pregnant or breastfeeding women, those with systemic inflammatory disease, those on medications that affect lipoprotein metabolism, minors, or those unable to consent are excluded and unlikely to benefit from participation.

Why it matters

Potential benefit: If successful, the findings could show that tighter blood sugar control improves HDL composition and function and potentially lowers cardiovascular risk in people with type 1 diabetes.

How similar studies have performed: Previous research indicates glycemic control can influence lipid levels and HDL function, but direct evidence that improving glycemic control restores HDL anti-atherogenic functions in type 1 diabetes is limited, so this approach is partly novel.

Eligibility criteria

Inclusion Criteria:

Control group non-diabetic and non-dyslipidemic :

* A person who has giver written consent
* Fasting blood glucose \< 1,10 g/L
* Triglycerides \< 1,50 g/L (\< 1,70 mmol/L).
* HDL cholesterol \> 1,03 mmol/L (men) or \> 1,30 mmol/L (women).
* LDL cholesterol \< 1,60 g/L.

Type 1 diabetes group :

* A person who has giver written consent
* Treated type 1 diabetes (regardless of the route of insulin administration).
* HbA1c \> 8.0% (\> 64 mmol/mol).

Exclusion Criteria:

All participants :

* A person who is not enrolled in or eligible for a social security program
* A person subject to a legal protective measure (guardianship, tutorship)
* A person subject to a judicial protective measure
* Pregnant women, women in labor, or breastfeeding women
* Adults who are legally incompetent or unable to give informed consent
* Minors
* Systemic inflammatory disease
* Medications that affect lipoprotein metabolism: immunosuppressive therapy, long-term corticosteroid therapy.

Control group non-diabetic and non-dyslipidemic :

* Diabetes or use of an antidiabetic medication.
* Dyslipidemia or use of lipid-lowering medication.
* Cardiovascular disease (history of stroke, myocardial infarction, coronary artery disease).
* Kidney disease (glomerular filtration rate CKD-EPI \< 75 mL/min/1.73 m²)
* Presence of metabolic syndrome defined by the presence of at least three of the following criteria (NCEP-ATP III criteria):

  * waist circumference \> 102 cm in men, \> 88 cm in women;
  * fasting triglycerides \> 1.70 mmol/L ( \> 1.50 g/L);
  * HDL cholesterol \> 1.03 mmol/L in men and 1.29 mmol/L in women;
  * systolic blood pressure ≥ 130 mmHg and/or diastolic blood pressure ≥ 85 mmHg;
  * fasting blood glucose ≥ 6.10 mmol/L (≥ 1.10 g/L).

Type 1 diabetes group:

* Diagnosis of type 1 diabetes within 12 months prior to enrollment.
* Glomerular filtration rate (CKD-EPI) \< 60 mL/min/1.73 m².
* Albuminuria ≥ 30 mg/g creatinine.
* Initiation of lipid-lowering therapy within the month prior to the study.

Exclusion criteria:

Type 1 diabetes group:

\- Initiation of lipid-lowering therapy during the 3 months of the study

Where this trial is running

Dijon

• Chu Dijon Bourgogne — Dijon, France (RECRUITING)

Study contacts

• Study coordinator: Benjamin BOUILLET

Conditions: Type 1 Diabetes