The goal of this clinical trial is to investigate how a short-term interruption of metformin treatment affects insulin sensitivity, glucose control, and metabolic flexibility in adults with metabolic syndrome who are taking metformin as part of their usual medical treatment. Temporary interruptions in metformin treatment may occur in real-life situations, such as missed doses, medication access problems, travel, or planned short-term discontinuation for clinical reasons. This study aims to understand whether stopping metformin for 14 days leads to rapid changes in glucose metabolism or whether the effects of previous metformin treatment may persist during a short period without the medication.
The main questions it aims to answer are:
Does stopping metformin for 14 days worsen glucose control or insulin sensitivity measured by oral glucose tolerance tests, HbA1c, and continuous glucose monitoring?
Does stopping metformin for 14 days affect metabolic flexibility, measured by indirect calorimetry during the oral glucose tolerance test?
Does stopping metformin for 14 days affect blood lipids, liver and inflammatory markers, red blood cell parameters, kidney function markers, fasting lactate levels, blood pressure, or heart rate?
Researchers will compare participants who stop metformin for 14 days with participants who continue their usual metformin treatment to see whether temporary metformin discontinuation affects insulin sensitivity, glucose control, metabolic flexibility, and other cardiometabolic markers.
Participants in the metformin discontinuation group will stop taking metformin for 14 days. They will attend study visits on day 0, day 4, day 7, and day 14. At each visit, they will complete an oral glucose tolerance test, have blood samples taken, and undergo indirect calorimetry measurements before and after the glucose drink. Blood pressure and heart rate will also be measured during the test. Participants will wear a continuous glucose monitor throughout the 14-day period to track glucose levels and help detect any potentially unsafe increase in blood glucose.
Participants in the usual-treatment group will continue taking metformin as prescribed. They will attend study visits on day 0 and day 14. At each visit, they will complete an oral glucose tolerance test, have blood samples taken, and undergo indirect calorimetry, blood pressure, and heart rate measurements during the test.
At the study visits, researchers will assess glucose and insulin responses, HbA1c, continuous glucose monitoring data, metabolic flexibility, blood lipid profile, liver and inflammatory markers, red blood cell parameters, kidney function markers, fasting lactate levels, blood pressure, and heart rate.