Glycemic changes in women with type 1 diabetes during their menstrual cycle

Glycemic Variations During the Menstrual Cycle in Women With Type 1 Diabetes: the GLYMETY Study

This study is testing how changes in hormones during the menstrual cycle affect blood sugar levels and insulin needs in women with type 1 diabetes.

Quick facts

• Study type: Observational
• Enrollment: 86 (estimated)
• Ages: 18 Years to 50 Years
• Sex: Female
• Sponsor: Institut de Recherches Cliniques de Montreal (other)
• Locations: 1 site (Montreal, Quebec)
• Trial ID: NCT05258292 on ClinicalTrials.gov

What this trial studies

This observational study aims to investigate glycemic fluctuations in women with type 1 diabetes throughout their menstrual cycle. By utilizing continuous glucose monitoring (CGM) data, the study will analyze insulin requirements and glycemic variations in a large cohort of women. The research focuses on understanding how hormonal changes during the menstrual cycle may affect insulin sensitivity and overall glycemic control. Participants will be required to share their CGM data and maintain a record of their menstrual cycles using a smartphone or tablet.

Who should consider this trial

Good fit: Ideal candidates for this study are females aged 18 to 50 living in Canada, diagnosed with type 1 diabetes or LADA, and using insulin therapy and continuous glucose monitoring.

Not a fit: Patients using hormonal contraception that eliminates menses or those with clinically significant nephropathy may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved management strategies for women with type 1 diabetes, allowing for better glycemic control during different phases of their menstrual cycle.

How similar studies have performed: While there have been small studies on this topic, this research aims to provide more comprehensive data, making it a novel approach in understanding glycemic variations related to the menstrual cycle.

Eligibility criteria

Inclusion Criteria:

1. Females aged 18 to 50 living in Canada.
2. Clinical diagnosis of type 1 diabetes or latent autoimmune diabetes in adults (LADA) for at least one year.
3. Using insulin pump therapy, multiple daily injections or automated insulin delivery systems for at least 3 months.
4. Using a continuous glucose monitoring (CGM) system.
5. Having at least one menses in the last 40 days.
6. Accepting to share CGM data with the research team and if applicable insulin pump data.This access will be limited to the study period.
7. Having a smartphone or tablet to follow menstrual cycles.
8. Stable weight (less than 5% variation in the last 3 months).

Exclusion Criteria:

1. Using a hormonal contraception method that eliminates menses (Depo Provera, progestin intrauterine device, extented-cycle regimen with birth control pill)
2. Using regular insulin (Entuzity U500, Novolin ge Toronto or Humulin R).
3. Clinically significant nephropathy (eGFR \< 30 ml/min/1.73m2, planned or on dialysis) or neuropathy (e.g., known uncontrolled gastroparesis) as judged by the investigator.
4. Recent (\< 6 months) acute macrovascular event (e.g., acute coronary syndrome or cardiac surgery).
5. Anticipated therapeutic change (including change of insulin type and/or type of CGM sensor, insulin pump or AID (automated insulin device) system) between admission and end of the study.
6. Anticipated change in contraception method or plan to begin or stop a contraceptive method.
7. Anticipated need to use acetaminophen during the study period at a dose above 1g every 6 hours.
8. Pregnancy (ongoing or current attempt to become pregnant)
9. Breastfeeding
10. Uncontrolled thyroid disease (TSH should be in target range and treatment stable for at least 6 weeks).
11. Severe hypoglycemic episode within two weeks of screening
12. Severe hyperglycemic episodes requiring hospitalization in the last 3 months.
13. Current use of glucocorticoid medication (except low stable dose and inhaled steroids and stable adrenal insufficiency treatment e.g., Cortef®)
14. Agents affecting gastric emptying (Motilium®, Victoza®, Ozempic®, Trulicity®, Byetta® and Symlin®) as well as oral anti-diabetic agents (Metformin, Prandase®, DPP-4 inhibitors) unless at a stable dose for 3 months and without anticipated change during the study.
15. Current use of SGLT-2 inhibitors unless at a stable dose for at least 3 months, without anticipated change during the study and appropriate ketone testing is performed.
16. Other serious medical illnesses which likely interfere with study participation or with the ability to complete the study by the judgment of the investigator.
17. Anticipation of a significant change in exercise or diet regimen between admission and end of the study (i.e., starting or stopping an organized sport; planned significant diet change).
18. Anticipated radiologic examination incompatible with CGM wear for more than 10 days between admission and end of the study (e.g., repeated MRI).
19. In the opinion of the investigator, a participant who is unable or unwilling to complete the study.
20. If taking medication for hypothyroidism, no change of dose (Levothyroxin) in the last 6 weeks.

Where this trial is running

Montreal, Quebec

• Institut de recherches cliniques de Montréal — Montreal, Quebec, Canada (RECRUITING)

Study contacts

• Principal investigator: Rémi Rabasa-Lhoret — Institut de recherches cliniques de Montréal
• Study coordinator: Anne Bonhoure

Conditions: Type1diabetes, Menstrual cycle, Continuous glucose monitoring, Insulin dose, Physical activity, Food intake