• Rationale: Glucose control in patients with kidney disease is challenging, as traditional metrics can be unreliable and there is a high risk of hypoglycemia (low blood sugar). Although RT-CGM has shown benefits in other groups, its efficacy in patients with advanced kidney damage needs to be validated to improve their quality of life and prevent disease progression.

• Main objective: To determine whether the use of RT-CGM is more effective than usual care (capillary blood glucose monitoring with a glucometer) in maintaining patients within an optimal glucose range (70-180 mg/dL) over a three-month period.

• Study population: We plan to include 30 patients over 18 years of age with type 2 diabetes and chronic kidney disease (with a glomerular filtration rate less than 60 ml/min), who use insulin and are not on renal replacement therapy such as dialysis.

• Methodology: The study is a randomized clinical trial consisting of two phases:

  1. Selection period (15 days): Blinded monitoring is performed to obtain baseline data.
  2. Treatment period (90 days): Patients are divided into two groups: the intervention group, which will use the CGM-RT with alarms configured for high and low levels, and the control group, which will continue with traditional fingerstick monitoring.

• Metrics to be evaluated: In addition to time in range, researchers will analyze episodes of hypoglycemia and hyperglycemia, glycemic variability, glycated hemoglobin (HbA1c) levels, and device accuracy.

• Ethical and logistical considerations: The study complies with international and national regulations, guaranteeing the confidentiality and autonomy of the participants. The project has a 24-month timeline and a detailed budget to cover medical personnel, monitoring sensors (Sinocare i3), and laboratory tests.

Patients diagnosed with type 2 diabetes mellitus and chronic kidney disease treated at the San Ignacio University Hospital in the outpatient clinic who meet the inclusion criteria will be identified. Once identified, they will be invited to participate in this study and will undergo the informed consent process, which will include, for those who accept, completing and signing the informed consent document (Appendix 1). It is clarified that the only intervention to be evaluated will be real-time continuous glucose monitoring; the patient's therapy will not be modified. The study will comprise a selection period and a treatment period.

4.3.1 Selection Period Potential subjects will sign an informed consent form before undergoing any procedure related to the study. During this phase, blinded continuous glucose monitoring will be performed to obtain baseline metabolic control data for 15 days prior to randomization. During this period, participants will be instructed to measure capillary blood glucose according to standard clinical practice. During this follow-up period, seven daily blood glucose readings will be taken to evaluate the device's accuracy in all patients.

4.3.2 Treatment Period Once the blinded monitoring data has been downloaded, randomization will begin. A simple, computer-generated randomization code will be used, managed centrally by a person who will not be aware of each patient's clinical characteristics. The assignment determined by this mechanism cannot be changed by the treating physicians.

• Intervention group (users of real-time continuous glucose monitoring). Participants in the intervention group will be instructed on the use of real-time continuous glucose monitoring. This training will be provided by nursing staff and will include instruction on device use, alarm management, and recommendations for responding to hypoglycemic episodes reported by the device. Alarms will be configured as follows: High Glucose Alert ≥240 mg/dL and Low Glucose Alert ≤70 mg/dL. Data uploaded to the platform by the device will be reviewed monthly by a physician trained in diabetes management, who will make appropriate adjustments to therapy if participants experience hypoglycemic episodes (<54 mg/dL and <70 mg/dL) or recurrent hyperglycemic episodes (>180 mg/dL), according to basal and prandial insulin titration recommendations. This group will be instructed to confirm readings below 70 mg/dL and above 240 mg/dL with capillary blood glucose monitoring to evaluate the device's accuracy within these ranges.
• Control group: Continuous glucose monitoring will be installed, blinded to measure baseline glycemic control metrics and at the end of the study. Patients assigned to the control group will receive routine nursing education on glucometer use, frequency of capillary blood glucose monitoring, and recommendations for managing hypoglycemic episodes. Capillary glucose data will be reviewed monthly by a physician trained in diabetes management, who will make appropriate adjustments to therapy if subjects experience hypoglycemic events (<54 mg/dL and <70 mg/dL) or recurrent hyperglycemic events (>180 mg/dL), according to basal and prandial insulin titration recommendations.

4.2.1 Inclusion Criteria

• Age over 18 years
• Chronic kidney disease defined as a glomerular filtration rate (GFR) of less than 60 ml/min/1.73 m², in at least two measurements within the six months prior to inclusion.
• Treatment with basal insulin, basal-bolus regimen, or co-formulation with or without oral antidiabetic agents, with or without a GLP-1 analogue, with stable treatment for the last 3 months.

4.2.2 Exclusion Criteria

• Type 1 diabetes.
• Severe cognitive impairment or dysfunction that prevents device management.
• Chronic kidney disease on renal replacement therapy (peritoneal dialysis or hemodialysis).
• Patients with a history of kidney transplantation.

The datasets generated and/or analyzed during the current study will not be publicly available because they contain clinical data from patients being monitored at Hospital Universitario San Ignacio.