Management of patients with type 1 Diabetes Mellitus has been changing rapidly in recent years, due in part to the introduction of new technologies such as Apps that recommend insulin boluses, or the use of continuous blood glucose sensors. This fact also entails a change in the care the investigators provide to these patients, facilitating virtual interaction without the need for the patient to go to the consultation, but having all the information necessary to modify treatment doses. There are no studies that compare the influence on glycemic control of conventional management with respect to virtual visits.

The investigators have proposed a randomized cohort study, with the aim to compared the changes in glycated hemoglobin in a group of patients with DM1 of the reference area of the "Hospital Comarcal de l´Alt Penedès" followed by telemedicine respect to the usual management in presential consultation.

Classic management of patients with type 1 diabetes (T1D) by endocrinologists consisted of carrying out a visit every 3-6 months in which HbA1c, microalbuminuria and a notebook with a variable number of annotated controls had been reviewed. In an accelerated way, the management of T1D has clearly been modified with the irruption of new technologies. Devices such as insulin bolus calculators, continuous glucose sensors, or continuous insulin pumps have been appeared and improved. In last months, continuous glucose monitors (CGM) for patients with T1D have been included in public funding in some cases. This fact is also associated with a considerable increase in the number of patient data, and new parameters to analyzed have appeared, with the same importance as HbA1c. Thus, percentage of time in optimal glycemic range, percentage of time in hypoglycemia, coefficient of variation of glycemia, or the mean glycemia are new parameters that the investigators have now been included in the follow-up.

The handling of such amount of data has mainly two repercussions: on the one hand, if these data are well analyzed it is easier to make changes in the treatment, which can conduce to a better disease management such as an improvement in metabolic control or a reduction in hypoglycemia number events. On the other hand, in routine clinical practice it has been found that the fact that patients have higher number of data raises more doubts about theirs treatment and other aspects of their disease, which motivate a greater number of consultations, usually telephone or unscheduled, generating a greater delay in the consultation, occupying spaces assigned to the emergency room or in time slots assigned to other patients.

In this way, telemedicine could be very useful in T1D management. These new devices allow data to be downloaded on secure digital platforms that make it possible for the doctor to have all the patient's blood glucose data without the presential visit of patient to hospital. Some of these platforms also allow safe communication channels between doctors and patients (teleconference, chats). The main benefit that telemedicine can provide is that allow doctors have a very narrow control, unacceptable in routine practice, which allows to interpreted the large volume of data that is generated and to do treatment recommendations, which can improve the metabolic control of the patient.

To date there are few studies on telemedicine in T1D. In this regard, a systematic review reported promising data in terms of HbA1c reduction in 3-6 months interventions, although it do not allow a robust conclusion due to the heterogeneity of the intervention in included studies, the absence of a control group and the small number of patients included2.

Furthermore, the benefits of telemedicine in management of T1D may go beyond the improvement of metabolic control. It must be considered that most T1D patients are young people of working age and that in some areas such as "l´Alt Penedès" there is an important geographical dispersion.

Thus, telemedicine could reduce trips to hospital with benefits on quality of life and reduce indirect costs such as travel costs, lost working hours, etc. In this sense, the Coyote study, carried out in the United States with a sample of 40 T1D subjects between 18-25 years of age, demonstrated that telemedicine was capable of improving the quality of life and saving 6 hours on average between travel to hospital, medical visit and return to work or university1. It should be noted that this study, which is considered a benchmark in its field, did not have a control group nor did it study changes in metabolic control.

On the other hand, being able to establish virtual contact channels between the patient and the doctor with a quick response from the doctor can be reflected in a reduction in the number of unexpected visits or contacts with the Emergency Department. Finally, it must be considered that virtual visits, although they are more frequent than face-to-face ones, are shorter and therefore the total time that doctor spends with the patient does not have to be superior to conventional management.

Hypothesis: Use of telemedicine in patients with T1D allows a closer control of their disease that results in a improve of metabolic control without increasing the number of face-to-face visits.

Inclusion Criteria:

• Patients with T1D over 18 years of age
• Duration of T1D greater than 6 months
• Access to smartphones
• In those patients with CGM, the minimum time for handling the sensor before randomization will be 2 months.

Exclusion Criteria:

• Inability to handle smartphones or Apps to manage T1D.
• Admission due to acute decompensation of TD1 in previous 3 months, presence of more than one severe monthly hypoglycemia, or any other circumstance that requires frequent visits and intensive diabetes education
• Inability to sign the informed consent