Red Blood Cell Parameters and Their Correlation with Glycemic Control Among Type 2 Diabetic Adult Patients in a Tertiary Care Center: An Observational Cross Sectional Study

ABSTRACT Introduction: Persistent hyperglycaemia in type 2 diabetes mellitus (T2DM) alters red blood cell (RBC) structure, membrane properties and haemoglobin through glycation and oxidative stress. RBC parameters are inexpensive components of the routine complete blood count and may reflect glycaemic status. This study compared RBC parameters between T2DM patients with good and poor glycaemic control. Methodology: This observational cross-sectional study was conducted in the Department of General Medicine of a tertiary care hospital in Jodhpur. Fifty adults with T2DM were divided by HbA1c into a good control group (HbA1c <7%, n=25) and a poor control group (HbA1c ≥7%, n=25). Patients with known anaemia, haematological disorders, vitamin B12, folate or iron deficiency, chronic liver or kidney disease, HIV, tuberculosis, recent transfusion or pregnancy were excluded. RBC count, haematocrit (HCT), haemoglobin (Hb), mean corpuscular volume (MCV) and mean corpuscular haemoglobin concentration (MCHC) were measured on a Beckman Coulter UniCel DxH 800 analyser and HbA1c by HPLC. Groups were compared using the independent t-test or Mann-Whitney U test; p <0.05 was considered significant. Results: Mean HbA1c was 8.19 ± 0.70% in the poor control group and 6.70 ± 0.26% in the good control group. Compared with the good control group, the poor control group had significantly lower RBC count (4.71 ± 0.53 vs 5.21 ± 0.30 ×10¹²/L; p=0.0002), HCT (37.42 ± 4.68 vs 44.51 ± 3.14%; p<0.0001), Hb (12.44 ± 1.63 vs 14.81 ± 1.03 g/dL; p<0.0001) and MCV (79.76 ± 5.31 vs 89.29 ± 5.36 fL; p<0.0001), and significantly higher MCHC (34.36 ± 1.75 vs 33.36 ± 0.86 g/dL; p=0.014). Age, sex, residence and duration of diabetes were similar between the groups. Conclusion: Poor glycaemic control in T2DM is associated with lower RBC count, HCT, Hb and MCV and higher MCHC. RBC parameters may serve as simple, low-cost supplementary indicators of glycaemic status, although larger studies are needed. Keywords: Type 2 diabetes mellitus; red blood cell parameters; glycaemic control; HbA1c; haemoglobin; haematocrit; MCHC