The goal of this observational study is to learn about the effects of different types of anemia on HbA1c test results in non-diabetic adults who have anemia but do not have diabetes. The main question it aims to answer is:

- Do different types of anemia (iron deficiency, vitamin B12/folate deficiency, thalassemia, and anemia of chronic illness) cause HbA1c levels to be falsely high or low in people without diabetes?

Type of the study:

- Observational cross-sectional study.

Site of the Study :

- Sohag University Hospital and hematology or endocrinology outpatient clinic.

Study population:

• Non-diabetic adult individuals attending the outpatient clinics and/or admitted to the internal medicine departments of Sohag University Hospital .
• Participants will be classified into different groups based on the presence and type of anemia (e.g., iron deficiency anemia, vitamin B12 deficiency anemia, folate deficiency anemia, anemia of chronic disease), in addition to a control group of non-anemic individuals.

All patients included in the study will be subjected to:-

• Medical history and clinical examination: Complete personal and family history with special emphasis on hematological disorders and history of diabetes or antidiabetic medications.

• Laboratory investigations:

  • Complete blood count (CBC) with red cell indices (MCV, MCH, RDW).
  • Iron profile (for diagnosis of iron deficiency anemia) (Serum iron , Serum ferritin , Total iron-binding capacity (TIBC) , Transferrin saturation
  • HbA1c level and Fasting plasma glucose (FPG) to confirm non-diabetic status.
  • Vitamin Assessment ( Serum vitamin B12 level )
  • Markers of Chronic Disease / Inflammation : C-reactive protein (CRP) or erythrocyte sedimentation rate (ESR)

Inclusion Criteria:

- Adult participants aged 18 years and above.

• Non-diabetic individuals, defined as:

• Fasting plasma glucose < 126 mg/dL and/or

• HbA1c < 6.5%, with no prior diagnosis of diabetes mellitus.

• Individuals diagnosed with anemia based on WHO criteria:

  • Hemoglobin < 13 g/dL in males
  • Hemoglobin < 12 g/dL in female
  • Patients with hemolytic anemia including thalassemia ( thalassemia trait and intermediate ) , sickle cell ( trait and disease ).

• Patients with confirmed specific types of anemia, based on laboratory evaluation:

  • Iron deficiency anemia
  • Vitamin B12 deficiency anemia
  • Folate deficiency anemia
  • Anemia of chronic diseases

Exclusion Criteria:

• Known cases of diabetes mellitus or prediabetes.
• Recent blood transfusion within the last 3 months.
• Use of medications known to affect HbA1c levels
• Acute illness or infection at the time of enrollment.
• Pregnant women
• Hematological malignancies

Non-diabetic adult individuals attending the outpatient clinics and/or admitted to the internal medicine departments of Sohag University Hospital . Participants will be classified into different groups based on the presence and type of anemia (e.g., iron deficiency anemia, vitamin B12 deficiency anemia, folate deficiency anemia, anemia of chronic disease), in addition to a control group of non-anemic individuals.