Effects of Pre-Exercise Basal Insulin Manipulation on Glucose Dynamics in Females vs. Males With Type 1 Diabetes: A Cross-Over Study
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 18
- 试验地点
- 1
- 主要终点
- Mean Rate of Capillary Blood Glucose (CBG) Decline
研究概览
简要总结
The Purpose of the Study The purpose of this study is to compare how blood sugar levels change during exercise in men and women with type 1 diabetes (T1D). Researchers want to understand if biological sex affects the risk of low blood sugar (hypoglycemia) during physical activity. Additionally, the study examines whether reducing the background (basal) insulin dose before exercise is effective at keeping blood sugar stable.
Study Population The study includes active adults (men and women) aged 18-45 who have lived with type 1 diabetes for at least 18 months and use an insulin pump.
What Happens During the Study
Participants complete three laboratory visits:
Visit 1: A fitness test on a treadmill to measure the participant's aerobic capacity.
Visits 2 & 3: Two 60-minute moderate-intensity exercise sessions on a treadmill.
In one session, participants reduce their basal insulin by 50% starting 90-120 minutes before exercising.
In the other session, they maintain their usual insulin dose.
Researchers measure blood sugar every 10 minutes during exercise and collect blood samples before and after the sessions to monitor hormone levels.
Study Design This is a randomized crossover study, meaning every participant performs both exercise strategies in a random order to serve as their own control.
详细描述
Background and Rationale:
Physical activity is highly recommended for individuals with type 1 diabetes (T1D), but managing blood glucose during exercise remains a significant challenge. A common strategy to prevent exercise-induced hypoglycemia (low blood sugar) is the reduction of the basal insulin infusion rate (BIRR) before starting physical activity. However, most guidelines are based on research conducted primarily in male cohorts. This study aims to address this knowledge gap by characterizing sex differences in glucose dynamics during prolonged moderate-intensity exercise and evaluating the effectiveness of a 50% BIRR strategy in both men and women.
Study Design:
This study follows a prospective, randomized, crossover design. Each participant serves as their own control, completing two distinct experimental exercise sessions in a randomized order to compare different insulin management strategies.
Study Procedures:
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 45 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Adults aged 18 to 45 years.
- •Diagnosis of Type 1 Diabetes (T1D) for at least 18 months.
- •Current use of an insulin pump (Continuous Subcutaneous Insulin Infusion - CSII) for diabetes management.
- •Regular physical activity level, defined as at least 150 minutes of aerobic exercise per week across three or more sessions for at least 4 weeks prior to the study.
- •Ability to perform 60 minutes of continuous treadmill running.
- •Aerobic fitness level (VO2peak) of ≥ 30 mL·kg-¹·min-¹ for females or ≥ 32 mL·kg-¹·min-¹ for males.
排除标准
- •Most recent HbA1c > 9.9% (85 mmol/mol).
- •C-peptide levels ≥ 0.7 nmol/L.
- •Presence of significant diabetes complications (e.g., proliferative retinopathy, nephropathy, or symptomatic neuropathy).
- •Use of concomitant medications affecting glucose metabolism other than insulin (e.g., steroids, SGLT2 inhibitors, GLP-1 receptor agonists, or non-selective beta-blockers).
- •History of hypoglycemia unawareness.
- •Occurrence of severe hypoglycemia resulting in seizure, coma, or hospitalization within the 6 months prior to recruitment.
- •Adherence to a low-carbohydrate or ketogenic diet (<30 g of carbohydrates per day).
- •Current engagement in shift work.
- •For female participants: presence of primary or secondary amenorrhea (cessation of menstruation for >12 months).
- •Uncontrolled hypertension (Systolic BP > 200 mmHg or Diastolic BP > 110 mmHg).
- •Known cardiovascular disease or significant cardiovascular risk factors (e.g., ischemic heart disease).
研究组 & 干预措施
50% Basal Insulin Reduction (INS_RED)
Participants perform a 60-minute moderate-intensity treadmill session after reducing their habitual basal insulin infusion rate by 50%. This reduction is initiated 90-120 minutes before the start of exercise.
干预措施: 50% Pre-Exercise Basal Insulin Rate Reduction (BIRR) (Other)
50% Basal Insulin Reduction (INS_RED)
Participants perform a 60-minute moderate-intensity treadmill session after reducing their habitual basal insulin infusion rate by 50%. This reduction is initiated 90-120 minutes before the start of exercise.
干预措施: Habitual Basal Insulin Rate Maintenance (Other)
Full Habitual Basal Insulin (INS_FULL)
Participants perform a 60-minute moderate-intensity treadmill session while maintaining their full habitual basal insulin infusion rate (no adjustment made prior to or during exercise).
干预措施: 50% Pre-Exercise Basal Insulin Rate Reduction (BIRR) (Other)
Full Habitual Basal Insulin (INS_FULL)
Participants perform a 60-minute moderate-intensity treadmill session while maintaining their full habitual basal insulin infusion rate (no adjustment made prior to or during exercise).
干预措施: Habitual Basal Insulin Rate Maintenance (Other)
结局指标
主要结局
Mean Rate of Capillary Blood Glucose (CBG) Decline
时间窗: During the 60-minute exercise session.
The average rate at which blood glucose levels decrease during the 60-minute moderate-intensity exercise session, measured in mg/dL per 10 minutes. This metric is used to characterize glucose dynamics and compare the impact of insulin reduction versus full dose across biological sexes.
次要结局
- Incidence of Exercise-Induced Hypoglycemia(During the 60-minute exercise session.)
- Time to Onset of Hypoglycemia(During the 60-minute exercise session.)
- Changes in Plasma Counter-Regulatory Hormone Levels(Baseline (pre-exercise) and 60 minutes (immediately post-exercise).)
- Substrate Utilization (Respiratory Exchange Ratio)(Throughout the 60-minute exercise session.)
研究者
Naama Constantini
Prof.
Shaare Zedek Medical Center