Diabetes mellitus (DM) is an epidemic disease, with approximately 463 million persons diagnosed with it. Of those, 90% are patients with type 2 DM (T2DM). Some estimates indicate that 700 million cases of DM will be reported in 2045. T2DM develops due to insulin resistance, leading to reduced insulin secretion. DM has a number of associated complications, such as nephropathy, neuropathy, and cardiovascular disease.

The health status of normal individuals and patients with various diseases is commonly monitored using the complete blood count (CBC). In patients with T2DM, the CBC can be used as a follow-up test, which will help in reducing complications associated with the disease. Some CBC parameters have also been used as prognostic markers for T2DM. One of these markers is the red cell distribution width (RDW), which measures the variability in the sizes of red blood cells (RBCs) and is considered an indicator of their heterogeneity. The evidence associating RDW with a higher risk of mortality has been expanding since the initial report of its prognostic utility in heart failure patients. Multiple studies have shown that elevated RDW values are associated with many human diseases, such as cancer, cardiovascular disease, and diabetes, and are also associated with disease activity or complications of diseases. The RDW can be used diagnostically in patients with T2DM and other illnesses, as patients with T2DM frequently show alterations in various hematological properties, including changes in the structure, metabolism, and function of blood cells. These alterations can be caused by different factors, such as excessive levels of reactive oxygen species (ROS), leading eventually to oxidative stress and the dysfunction of RBCs.

The relationship between RDW and T2DM has been studied for several years, and there are no consistent results.

Inclusion Criteria:

• Patients diagnosed to have Uncontrolled type 2 diabetes mellitus (HbA1C more than 7%)

Exclusion Criteria:

1. Patients diagnosed to have type 1 diabetes.

2. Patients are diagnosed to have secondary diabetes.

3. Clinical states associated with increased RDW:

   • Anemia (Female Hb less than 12, Male Hb less than 13) either due to hemolysis, or in response to ineffective red cell production, which can be caused by deficiencies in iron, vitamin B12 or folate.
   • After blood transfusions
   • Pregnancy, thrombotic thrombocytopenic purpura and inflammatory bowel disease.

Patients diagnosed to have type 2 diabetes