Study design and study settings
This was a cross sectional descriptive study and data was extracted retrospectively from the database and clinical records of patients who were referred to Haematology Unit of Teaching Hospital Jaffna for evaluation of anaemia during the study period.
Study population, Sample size and Sampling Technique
The study included all the patients above 60 years of age who underwent haematological examination for anaemia over a period of 6 months (1st September 2020 to 28th of February 2021) at heamatology unit, Teaching hospital, Jaffna.
To the best of our knowledge there were no studies published on pattern of anemia among geriatric population in Sri Lanka even though few general population prevalence studies were done. As our main objective is to identify the common hematological patterns of anemia we used the proportion identified in a study from India (normocytic anemia in 53.3% of patients followed by microcytic anemia (40%) and macrocytic anemia (6.6%) . In order to capture maximum sample size, sample size was calculated using each of above percentage separately and maximum number was taken for our study.
The sample size was estimated using estimate a proportion formula 
n = z2x P (1-P)/ d2
z -value at the confidence level = 95% is 1.96
Acceptable difference (d) = 0.05(5%)
Estimated Sample size
Sample size C.I. up to 0.10 wide
A sample size of 403 will yield a C.I. up to 0.10 wide for all the proportion mentioned above. So sample size was determined as 403.
Exclusion criteria: None
Ethical Approval: Ethical approval for this study was obtained from the Ethical Review Committee, Faculty of Medicine of University of Jaffna (Ref No: J/ERC/20/120/NDR/0239)
Sampling and recruitment procedure: There was no sampling technique applied and we collected data from all the patients’ records during the period and we were able to collect 1121 patients’ details for this study.
Data collection: Data were collected using data extraction sheets from the haematology record sheets of all anemia patients meeting the inclusion criteria maintained at haematology unit and collected by a trained data collector who was a medical officer working in the haematology unit and also one of the co-investigator. Data were extracted from the record sheets maintained at haematology unit, Teaching Hospital Jaffna.
For the diagnosis of anaemia WHO classification is used. Haemoglobin <13g/dl in men and <12g/dl in women is classified as anaemia. It is further classified in to mild, moderate and severe based on the degree of anaemia.
The diagnosis of different types of anaemia is based on following criteria and is concluded by the Consultant Haematologists
1. Anaemia of chronic disorders
The anaemia of chronic disease (ACD) is a common normochromic or mildly hypochromic anaemia that occurs in patients with a systemic disease
- Presence of systemic disorder included in the following list
- Mean corpuscular volume normal or mildly reduced (usually 77–82 fL)
- Mean corpuscular hemoglobin usually normal; occasionally reduced
- Serum iron reduced
- Total iron-binding capacity (transferrin) reduced
- Transferrin saturation mildly reduced
- Serum ferritin normal or increased
- C-reactive protein usually raised
- Erythrocyte sedimentation rate usually raised
- Associated Conditions
Especially osteomyelitis, bacterial endocarditis, tuberculosis, abscesses, bronchiectasis, chronic urinary tract infections, osteomyelitis, HIV
Other chronic inflammatory disorders
Rheumatoid arthritis, juvenile rheumatoid arthritis, polymyalgia rheumatica, systemic lupus erythematosus, scleroderma, inflammatory bowel diseases, thrombophlebitis, severe trauma
Carcinoma (especially metastatic or associated with infection)
Congestive heart failure, ischemic heart disease, AIDS
2.Iron Deficiency Anaemia(IDA)
Blood picture findings
Serum Ferritin < 30µg/L
Clinical history (Vegetarian)
Blood Picture findings
Response to B12 Trial
4. Mixed deficiency
Normocytic normochromic anaemia with low serum Ferritin
Combined morphological features of Vitamin B12/Folate deficiency and Iron deficiency on blood picture
5. Autoimmune Hemolytic anaemias
Blood picture findings
Elevated reticulocyte count
Elevated indirect bilirubin
Direct coombs test -positive
6.Non-Immune Hemolytic anemia
Blood picture findings
Elevated Reticulocyte count
Elevated Indirect Bilirubin
Direct coombs test -Negative
7. Anemia Associated with Hypothyroidism
Anemia with no other cause
Thyroid function tests – Suggestive of Hypothyroidism (High TSH)
8. Anaemia of renal disease
Anaemia with no other identifiable cause
Diagnosed chronic kidney disease
9. Haematological malignancy
Anaemia without any identifiable cause
Presence of diagnosis of a haematological malignancy (Acute Leukaemia /Multiple Myeloma /Lymphoma /Myeloproliferative neoplasm) based on blood picture and bone marrow biopsy
10.Anemia of acute blood loss
Anaemia with no other obvious cause
History of recent blood loss
Reticulocytosis without indirect bilirubinemia
11.Anemia of acute illness
Anaemia without obvious cause (Especially no obvious bleeding or hemolysis)
Admitted with acute /critical illness at ward setting /ICU for less than 1 week duration.
12. ACD + IDA
Fulfills the criteria for both anaemia of chronic disorders and iron deficiency anaemia
Meeting more than one criteria mentioned above other than ACD+IDA
Data were analyzed using a recommended statistical package (SPSS version 28.0).Quantitative variable were expressed as percentage with CI and also mean values were calculated with SD for numeric variable. Chi squared test is used to identify association,P value <0.05 is considered as statistically significant. Results are summarized in tables and figures.