A longitudinal follow-up study of a type 2 diabetes "lost to follow-up" cohort - positive effect on glycaemic control after changes in medication.

The aim of this study was to evaluate whether patients with type 2 diabetes (T2D) who had stopped attending their diabetes treatment system (referred to as "lost to follow-up", LTF) but who succeeded in improving their glycaemic control after returning to the diabetes treatment system had changes in their diabetes medication when compared with similar patients who did not show improvement. "LTFs" who had baseline haemoglobin A1 c (HbA1 c) ≥53 mmol/mol and succeeded in reducing HbA1 c ≥ 6 mmol/mol during a 12-30 month follow-up period after adhering again to their diabetes treatment system were compared with "LTFs" who had an unsatisfactory change in HbA1 c or with "LTFs" who maintained good glycaemic control throughout the 12-30 month follow-up period. Unsatisfactory change in HbA1 c was determined as HbA1 c ≥ 53 mmol/mol and change <6 mmol/mol after the 12-30 month follow-up period in their diabetes treatment system or HbA1 c < 53 mmol/mol when returning to the diabetes treatment system but ≥53 mmol/mol at the end of the 12-30 month follow-up period. "LTFs" with improvement in glycaemic control used a higher number of different anti-hyperglycaemic agents (P < 0.001) and their dosages of metformin increased (P < 0.05) when compared with "LTFs" without improvement or "LTFs" with satisfactory glycaemic control. Cholesterol-, LDL-cholesterol- and triglyceride-concentrations decreased during the 12-30 month follow-up period (P < 0.05) in "LTFs" with improved glycaemic control, but not in the other groups. "LTFs" with T2D who had poor glycaemic control seemed to require an increase in their anti-diabetic medication when attempting to improve their glycaemic control.