MRCP2-2364

A 42-year-old woman with type 1 diabetes mellitus has not attended the diabetic clinic for three years.

Examination shows no abnormalities.

Investigations show:

Haemoglobin 90 g/L (115-165)

MCV 94 fL (80-96)

Haematocrit 28% –

HbA1c 87 mmol/mol (20-42)

10.1% (3.8-6.4)

A blood smear shows normochromic, normocytic anaemia.

What is the most likely cause of the anaemia?