Anemia in older adults is an important clinical entity that contributes substantially to adverse health outcomes. Rather than being a normal consequence of aging, reduced hemoglobin levels in the elderly frequently indicate underlying pathological processes. The World Health Organization (WHO) defines anemia as hemoglobin <13 g/dL in men and <12 g/dL in women, criteria that remain applicable to older populations [1]. Even mild reductions in hemoglobin have been associated with diminished physical endurance, impaired cognition, increased risk of falls, prolonged hospitalization, and higher mortality.

Epidemiological data suggest that anemia affects a considerable proportion of individuals aged 60 years and above, with prevalence rising steadily with advancing age. Community-based studies report prevalence rates ranging from 10% to 24%, while substantially higher rates are observed among hospitalized elderly patients [2]. Importantly, anemia in this age group is independently linked to poorer survival and increased healthcare utilization, emphasizing the need for systematic evaluation [3].

The causes of anemia in geriatric patients are often multifactorial. Anemia of chronic disease, iron deficiency anemia, chronic kidney disease-related anemia, and deficiencies of vitamin B12 or folate constitute the majority of identifiable etiologies [4]. Nonetheless, a proportion of elderly individuals continue to have unexplained anemia despite detailed workup [5]. Accurate classification depends on comprehensive laboratory assessment, including red cell indices, iron profile, renal parameters, liver function tests, and relevant nutritional markers.

There is limited published data from Northeast India regarding the laboratory characteristics and etiological distribution of anemia in hospitalized elderly patients. Given the growing aging population and increasing burden of chronic diseases, region-specific data are essential. This study was therefore conducted to evaluate the laboratory profile and underlying causes of anemia in geriatric patients attending a tertiary care hospital in Northeast India

Study Design and Setting

This hospital-based cross-sectional observational study was conducted over 12 months at the Department of Medicine, Nemcare Hospital, Guwahati, Assam. The study aimed to evaluate the laboratory profile and etiology of moderate and severe anemia in elderly patients.

Sample Size Determination

The required sample size was calculated using the formula described by Wayne W. Daniel (2013):

where n represents the sample size, Z is 1.96 for a 95% confidence interval, P is the estimated prevalence of anemia (10.5%) based on the Third National Health and Nutrition Examination Survey (NHANES III), and D is the allowable margin of error (5% or 0.05). Using this formula, the minimum sample size for the study was determined to be 145 participants.

Sampling Technique

Consecutive sampling was employed. The first 145 elderly patients presenting with moderate or severe anemia were enrolled after providing information about the study purpose and procedures, and obtaining written informed consent in their preferred language.

Study Population

Inclusion Criteria

1. Age ≥60 years
2. Hemoglobin ≤10.9 g/dL in males and females
3. Willingness to participate and provide written informed consent

Exclusion Criteria

1. Age <60 years
2. Patients already diagnosed with anemia and receiving treatment
3. History of blood transfusion within the past month
4. History of major surgery within the past month
5. Refusal to participate or provide consent

Evaluation and Investigations

All participants underwent detailed history taking and physical examination. Baseline laboratory investigations included complete blood count, iron profile, liver function tests, and serum creatinine. Additional investigations were performed as clinically indicated, including peripheral blood smear, serum vitamin B12 and folate, stool examination for occult blood and parasites, thyroid function tests, gastrointestinal endoscopy, bone marrow aspiration/biopsy, hemoglobin electrophoresis, Coombs test, and serum protein electrophoresis (SPEP).

Ethical Considerations

The study protocol was approved by the Nemcare Institute Ethics Committee (Approval No. NHE/IEC/2023/005 dated 22/05/2023). Written informed consent was obtained from all participants, and confidentiality was maintained.

Data Collection and Analysis

Data were recorded in a structured proforma and entered into Microsoft Excel. Statistical analysis was performed using SPSS version 20. Descriptive statistics were calculated, and results were presented in text, tables, graphs, pie charts, and bar diagrams. Associations between categorical variables were assessed using the chi-square test. A p-value <0.05 was considered statistically significant, with a 95% confidence interval

Table 1: Hematological parameters for the elderly with anemia (N= 145).

Table 1 summarizes the hematological parameters of 145 elderly patients with anemia. The mean hemoglobin was 8.9 g/dL, indicating moderate to severe anemia. Red blood cell indices suggest predominantly normocytic anemia (mean MCV 83.6 fL), with mild variation in MCH and MCHC. Elevated RDW (15%) and ESR (41.5 mm/hr) reflect underlying heterogeneity and possible chronic inflammation. Platelet and total leukocyte counts showed wide variation, consistent with the diverse etiologies in this population.

The etiological analysis of anemia in the study population (N = 145) showed that anemia of chronic disease was the most frequent cause, affecting 72 participants (50%). Iron deficiency anemia was the second most common, observed in 46 participants (32%). Megaloblastic anemia was present in 11 participants (8%), dimorphic anemia in 9 participants (6%), and unexplained anemia accounted for 7 participants (5%).

Table 2: General Examination of Patients :

Table 3: Iron profile of the elderly with anemia (N= 145)

The hematological parameters related to iron metabolism in the elderly participants with anemia (N=145) revealed variability in iron status. The mean serum ferritin level was 157.36 ng/mL (± 122.9), with a median of 129 ng/mL, and levels ranged from 8 ng/mL to 500 ng/mL, indicating diverse iron stores among the participants. Serum iron levels had a mean of 56.89 μg/dL (± 35.7) and a median of 42 μg/dL, with values ranging from 20 μg/dL to 156 μg/dL, suggesting that some individuals experienced iron deficiency.

The mean Total Iron Binding Capacity (TIBC) was 352.33 μg/dL (± 67.76), with a median of 366 μg/dL, and TIBC values ranged from 200 μg/dL to 451 μg/dL, reflecting increased iron-binding capacity typically seen in iron deficiency anemia.

Age and Gender

The study included 145 elderly participants divided into three age groups: 60–70 years (70%, n = 101), 71–80 years (23%, n = 33), and 81–90 years (8%, n = 11). In the 60–70 years group, gender distribution was balanced (50% male, 50% female). In the 71–80 years group, females predominated (61%), while in the 81–90 years group, males were more frequent (64%). Previous studies show variable gender distribution in elderly anemia, with some reporting higher prevalence in females and others noting an increase in both sexes after 70 years, often due to chronic disease, malnutrition, or renal insufficiency [6–10, 16–22].

Symptoms

Gradual-onset symptoms were observed in 75% of participants. Easy fatigability was most common (35%, n = 51), followed by dizziness (26%, n = 37). Palpitations (8%), bleeding (7%), and frequent falls (6%) were less frequent. Recurrent infections were rare (1%). Other symptoms were reported in 18% of participants.

Comorbidities

Hypertension was the most prevalent comorbidity (31%, n = 45), followed by diabetes mellitus (21%, n = 30) and chronic kidney disease (16%, n = 23). Other comorbidities were present in 32% of participants.

General Examination

Pallor was observed in all participants (100%), and pedal edema in 30 patients (21%). No participants exhibited icterus, lymphadenopathy, clubbing, koilonychia, glossitis, angular stomatitis, or aphthous ulcers.

Hematological Parameters

The mean hemoglobin was 8.9 ± 1.9 g/dL (median 8.7), indicating moderate anemia. Mean RBC count was 3.27 ± 0.74 million/µL, with an MCV of 83.6 ± 1.01 fL. MCH and MCHC were within normal limits (27.23 ± 3.7 pg and 31.61 ± 2.5 g/dL, respectively). RDW averaged 15%, and ESR 41.5 mm/hr. Platelet and leukocyte counts showed wide variation.

Biochemical Parameters

Mean serum urea was 31.44 ± 2.06 mg/dL, and creatinine 1.24 ± 0.69 mg/dL. Liver function tests were largely normal, with mean AST 32.55 ± 12–80 U/L, ALT 34.39 ± 11–70 U/L, total bilirubin 0.99 mg/dL, and other parameters within reference ranges. Iron studies showed a mean ferritin of 157.36 ± 122.9 ng/mL, serum iron 56.89 ± 35.7 µg/dL, and TIBC 352.33 ± 67.76 µg/dL, reflecting variable iron status among participants.

Severity of Anemia

Moderate anemia was most common (64%, n = 93), while severe anemia affected 36% (n = 52). These findings are consistent with previous Indian studies reporting a higher prevalence of moderate anemia in the elderly [14, 53–59].

Type of Anemia

Anemia of chronic disease was most prevalent (50%, n = 72), followed by iron deficiency anemia (32%, n = 46), megaloblastic anemia (8%, n = 11), dimorphic anemia (6%, n = 9), and unexplained anemia (5%, n = 7). Similar patterns have been reported in multiple regional and international studies [6–12, 16–22].

Anemia is common among elderly patients, with moderate anemia being the most frequent severity. The leading causes were anemia of chronic disease and iron deficiency, while megaloblastic, dimorphic, and unexplained anemia were less prevalent. The condition was most common in the 60–70 years age group, and gender distribution varied with age. Fatigue and dizziness were the predominant symptoms, typically of gradual onset. Hypertension, diabetes, and chronic kidney disease were the most common comorbidities. Laboratory evaluation indicated variable iron stores and generally normal liver and kidney function. These findings emphasize the importance of early detection, comprehensive assessment, and individualized management of anemia in the geriatric population to reduce complications and improve overall health outcomes.

Conflicts of Interest

The authors declare no conflicts of interest.

Acknowledgments

The authors sincerely thank the staff and patients of Nemcare Hospital, Guwahati, for their cooperation and support during the study. Special thanks to the laboratory team for their assistance in sample analysis and data collection.

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