INS and type 1 diabetes mellitus: Although glycemic variability was not determined in this study, people with T1D usually have much higher glycemic variability than people with T2D because T1D is characterized by an absolute insulin deficiency, and thus people with T1D require exogenous insulin from disease onset, whereas increased glycemic variability in T2D denotes a progressive decline in residual beta-cell function in long-standing cases [43].