INS and type 2 diabetes mellitus: This classification system is based on various factors that differ between patients with T1D and T2D, such as age at disease onset, excessive weight, degree of insulin resistance (IR), presence of metabolic syndrome (MS), degree of loss of pancreatic β-cell function, presence of specific autoantibodies associated with β-cell destruction, presence of a systematic subclinical inflammatory state, concentration of C-peptide in the blood and requirement for treatment with insulin to survive [2].