Use of continuous glucose monitoring in patients with diabetes on peritoneal dialysis: poor correlation with HbA1c and high incidence of hypoglycaemia.

BackgroundAchieving adequate glycaemic control in patients with diabetes on peritoneal dialysis is challenging. Traditional assessment of glycaemia using HbA(1c) is difficult in such patients because of renal anaemia or carbamylation of haemoglobin, and significant glucose excursions may be masked. We describe three patients with diabetes on peritoneal dialysis with similar HbA(1c) levels, but with very different glucose profiles shown on continuous glucose monitoring. Case reportsPatient 1 was treated with gliclazide, and had a number of solutions with high glucose concentration in his dialysis prescription. Continuous glucose monitoring showed glucose levels >11mmol/l for >17h per day, and <4mmol/l for 72min per day with no symptoms. His HbA(1c) level was 61mmol/mol (7.7%). Patient 2 was treated with insulin. Continuous glucose monitoring showed glucose levels >11mmol/mol for 3.8h per day, and <4mmol/mol for 3.8h per day. His HbA(1c) level was 59mmol/mol (7.6%). Patient 3 was treated with pioglitazone and gliclazide, and glucose levels were >11mmol/l for 8h per day and <4mmol/l for 1.6h per day. His HbA(1c) was 62mmol/mol (7.8%). None of the patients was aware of hypoglycaemia during the periods of low glucose recorded on continuous glucose monitoring. ConclusionDespite similar HbA(1c) levels, our three patients had very different glucose profiles. These cases highlight the fact that HbA(1c) is frequently inadequate in reflecting glucose control in patients with diabetes on peritoneal dialysis, and we suggest that intermittent continuous glucose monitoring may allow safer management of glycaemia in such patients.