AN OBSERVATIONAL, CROSS-SECTIONAL STUDY ON HAEMATOLOGICAL ABNORMALITIES IN PATIENTS WITH TYPE 2 DIABETES MELLITUS ON METFORMIN FOR 5 YEARS OR MORE IN A TERTIARY CARE CENTER

Abstract

Introduction: Metformin, the preferred first line oral hypoglycaemic agent used in type 2 diabetes mellitus, is notorious to cause vitamin B12 deficiency which can lead to reversible macrocytic anaemia and/or neurological dysfunction. A simple and inexpensive test like complete blood count could go a long way in timely diagnosis and treatment of anaemia.

Aims and objectives: To observe the haematological abnormalities in patients using Metformin for 5years or more and to note the effects of age, sex, residence of the subjects, drug dose, duration and combination with other oral hypoglycaemic agents on such changes.

Methodology: In this observational and cross-sectional study, 100 patients aged 18-60 years with type 2 Diabetes Mellitus using Metformin for 5years or more were recruited after exclusion of use of drugs (vitamin or iron supplements, antiplatelets etc.). and alcohol, hypothyroidism, end-organ disease. They were subjected to complete blood count with RBC indices. Serum iron profile was sent for the microcytic group and serum vitamin B12 and folate estimation were done in the macrocytic group.

Results: 66 out of 100 were having anaemia of following types- 44 normocytic normochromic, 19 microcytic hypochromic (84.2% are iron-deficient) and 3 macrocytic (66.7% B12 deficient). Anaemia is more frequent in females aged 18-50y (71.8%), rural individuals (76.6%), people using increased daily dosage or insulin in combination with Metformin (p<0.05). Nevertheless no such relation could be elicited between duration of Metformin use and anaemia nor does Metformin show any effect on leukocyte or platelet counts.

Conclusion: Regular screening is imperative by physicians in such cases for timely detection of different types of anaemia and prompt treatment.