HbA1c Variability in Type II Diabetes

There are numerous possible reasons why it could be speculated that HbA1c variability may affect complication risk. Of interest are the concepts that both laboratory and clinic evidence suggests that periods of sustained hyperglycemia are 'remembered' (metabolic memory), this in turn is recognized to place patients at greater long-term risk of complications. As such it can be speculated that the detrimental effect of variability in HbA1c may be mediated via the same mechanism as 'metabolic memory' phenomenon. Aims: To determine whether treatment to one of 2 threshold levels will result in one group of type 2 diabetes patients having the same mean HbA1c but with differing HbA1c variability to that of another and related to markers of oxidative stress, inflammation and microvascular complications. To determine whether a difference in HbA1c variability between the 2 groups will reflect in changes in small nerve fibers assessed with the sensitive method of corneal confocal microscopy and cardiac autonomic function testing. To assess the reproducibility of HbA1c measurement from a whole blood samples initially analyzed and then stored at -80C until the end of the study (2-3 years), as well as storing an aliquot of haemolysate, for reanalysis at the end of the study. In one arm the investigators will intensify treatment in those with FPG\>140mg/dl until their FPG is \<90mg/dl, using whatever treatment is clinically appropriate for them, and only intensify it further if their FPG rises to \>140mg/dl again. In the other group the investigators will intensify if their FPG is \>115 mg/dl until it is \<=115 mg/dl and intensify further if \>115 mg/dl again. A total of 20 visits within a time frame of 2 and half years will be performed. Visits procedures will include routine biochemistry, eGFR, lipids, fasting glucose, insulin and full blood count, HbA1c, SHBG, hsCRP. EPIC and G-PAQ questionnaires will be collected. Autonomic function testing using deep breathing heart rate variability, and a sensitive measure of small fiber neuropathy using corneal confocal microscopy and a 24 hour urine collection for urinary isoprostanes to measure oxidative stress will be performed, at baseline, 12 and 24 months.

NCT Number	NCT02879409
Lead Sponsor	Weill Cornell Medical College in Qatar Collaborators: Hamad Medical Corporation, Sidra Medicine, University of Hull
Conditions	Diabetes Mellitus Type 2
Enrollment	150 participants
Start Date	2016-11
Primary Completion	2023-10-01 (estimated)
Study Completion	2026-10-01 (estimated)
Updated on ClinicalTrials.gov	2025-07-20