The 2021–2022 position of Brazilian Diabetes Society on insulin therapy in type 1 diabetes: an evidence-based guideline to clinical practice

BACKGROUND: Insulin therapy regimens for people with type 1 diabetes (PWT1D) should mimic the physiological insulin secretion that occurs in individuals without diabetes. Intensive insulin therapy, whether by multiple daily injections (MDI) or continuous subcutaneous insulin infusion (CSII), constitutes the fundamental therapy from the initial stages of type 1 diabetes (T1D), at all ages. This review is an authorized literal translation of part of the Brazilian Diabetes Society (SBD) Guidelines 2021–2022. This evidence-based guideline supplies guidance on insulin therapy in T1D. METHODS: The methods were published elsewhere in earlier SBD guidelines and was approved by the Internal Institutional Steering Committee for publication. Briefly, the Brazilian Diabetes Society indicated fourteen experts to constitute the Central Committee, designed to regulate the method review of the manuscripts, and judge the degrees of recommendations and levels of evidence. SBD Type 1 Diabetes Department drafted the manuscript selecting key clinical questions to do a narrative review using MEDLINE via PubMed, with the best evidence available, including high-quality clinical trials, metanalysis, and large observational studies related to insulin therapy in T1D, by using the Mesh terms [type 1 diabetes] and [insulin]. RESULTS: Based on extensive literature review the Central Committee defined ten recommendations. Three levels of evidence were considered: A. Data from more than one randomised clinical trial (RCT) or one metanalysis of RCTs with low heterogeneity (I(2) < 40%). B. Data from metanalysis, including large observational studies, a single RCT, or a pre-specified subgroup analysis. C: Data from small or non-randomised studies, exploratory analysis, or consensus of expert opinion. The degree of recommendation was obtained based on a poll sent to the panellists, using the following criteria: Grade I: when more than 90% of agreement; Grade IIa if 75–89% of agreement; IIb if 50–74% of agreement, and III, when most of the panellist recommends against a defined treatment. CONCLUSIONS: In PWT1D, it is recommended to start insulin treatment immediately after clinical diagnosis, to prevent metabolic decompensation and diabetic ketoacidosis. Insulin therapy regimens should mimic insulin secretion with the aim to achieve glycemic control goals established for the age group. Intensive treatment with basal-bolus insulin therapy through MDI or CSII is recommended, and insulin analogues offers some advantages in PWT1D, when compared to human insulin. Periodic reassessment of insulin doses should be performed to avoid clinical inertia in treatment.