Anemia is a major global public health problem affecting individuals across all age groups and is particularly prevalent among patients with chronic diseases. The World Health Organization (WHO) defines anemia as a hemoglobin concentration below 13 g/dL in adult men and below 12 g/dL in adult women [1,3]. Anemia results in reduced oxygen-carrying capacity of blood, leading to fatigue, impaired physical performance, and increased cardiovascular workload [2].

Iron deficiency anemia accounts for nearly half of all anemia cases worldwide; however, anemia of chronic disease is increasingly recognized among patients with long-standing illnesses such as diabetes mellitus [4]. Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder characterized by insulin resistance and progressive β-cell dysfunction. Its prevalence is increasing globally, contributing significantly to morbidity and mortality [6].

Several studies have demonstrated that patients with diabetes are at a higher risk of developing anemia compared to non-diabetic individuals, even in the absence of overt renal disease [2,9,16]. The etiology of anemia in diabetes is multifactorial and includes reduced erythropoietin production, chronic in inflammation, oxidative stress, autonomic neuropathy, and nutritional deficiencies [10,17,18].

Long-term use of antidiabetic medications such as metformin has been associated with vitamin B12 deficiency, further increasing the risk of anemia in diabetic patients [19,20]. Anemia in diabetes has been identified as an independent predictor of cardiovascular disease, progression of diabetic nephropathy, increased hospitalization, and premature mortality [10,11].

Despite its clinical importance, anemia often remains underdiagnosed in diabetic patients due to overlapping symptoms such as fatigue, weakness, and neuropathy [12]. Data on the prevalence of anemia among patients with T2DM in southern India, particularly Karnataka, are limited. Hence, this study was undertaken to determine the prevalence of anemia among patients with T2DM attending a tertiary care hospital in Hassan and to evaluate its association with age, gender, and glycemic control.

MATERIALS AND METHODS

Study Design and Setting

This retrospective observational study was conducted at the Diabetes Outpatient Department of HIMS Hospital, Hassan, Karnataka.

Study Population

Adult patients (≥18 years) diagnosed with type 2 diabetes mellitus who attended the outpatient department between January 1, 2023, and December 31, 2024.

Total number of Participants during study period were 18420.

Inclusion Criteria

• Confirmed diagnosis of type 2 diabetes mellitus
• Availability of hemoglobin and HbA1c values

Exclusion Criteria

• Type 1 diabetes mellitus
• Pregnant women
• Incomplete laboratory records

Data Collection

Data were obtained from the laboratory information system and included age, gender, hemoglobin concentration, and HbA1c levels.

Definitions

• Anemia: Hb <13 g/dL in men and <12 g/dL in women (WHO criteria) [3]
• Good glycemic control: HbA1c ≤7.5%
• Poor glycemic control: HbA1c >7.5%

Ethical Considerations

The study was approved by the Institutional Ethical Committee of Hassan Institute of medical Sciences Hassan.

• Since the study was retrospective,no direct consent from participants required
• Confidentiality of participants information was strictly maintained and all data were anonymised for analysis.

Statistical Analysis

Data were analyzed using SPSS version 26. Continuous variables were expressed as mean ± standard deviation, and categorical variables as percentages. Statistical significance was set at P < 0.05.

RESULTS

Table 1. Baseline Characteristics of Study Population

A total of 18,420 patients with T2DM were included in the study. Among them, 9,620 (52.2%) were males and 8,800 (47.8%) were females.

Table 2. Overall Prevalence of Anemia

Anemia was detected in 5,830 patients, resulting in an overall prevalence of 31.6%.

Table 3. Gender-wise Distribution of Anemia

Anemia was more prevalent among females (40.9%) compared to males (23.4%), and this difference was statistically significant (P < 0.05).

Table 4. Glycemic Control and Anemia

• Well-controlled diabetes (HbA1c ≤7.5%): anemia prevalence 29.1%
• Poorly controlled diabetes (HbA1c >7.5%): anemia prevalence 35.8%
• Poor glycemic control was significantly associated with anemia (P < 0.05).

Table 5. Age Distribution and Anemia

The mean age of anemic patients was 61.3 ± 0.22 years, whereas non-anemic patients had a mean age of 55.1 ± 0.14 years, indicating a significant association between advancing age and anemia (P < 0.05).

DISCUSSION

The present study demonstrates that anemia is a common comorbidity among patients with type 2 diabetes mellitus, with an overall prevalence of 31.6%. This finding supports previous reports indicating that anemia frequently coexists with diabetes and often remains underrecognized [2,12].

The prevalence observed in this study is comparable to findings reported by Adejumo et al., who observed anemia in approximately 30% of diabetic patients without renal impairment [2]. However, Sharif et al. reported a much higher prevalence of 63% [6]. This discrepancy may be attributed to differences in study populations, nutritional status, degree of glycemic control, and healthcare access.

A significantly higher prevalence of anemia was observed among female patients, consistent with previous studies by Alsayegh et al. and Sharif et al. [6,21]. Factors such as menstrual blood loss, iron deficiency, nutritional inadequacies, and sociocultural determinants may contribute to the increased vulnerability of women to anemia [22].

Poor glycemic control was found to be significantly associated with anemia in the present study. Similar observations were reported by Mounika et al., who demonstrated a higher incidence of anemia among patients with poorly controlled diabetes [23]. Chronic hyperglycemia leads to oxidative stress, which damages erythrocyte membranes and shortens red blood cell lifespan. Additionally, prolonged exposure to high glucose levels may impair bone marrow erythropoiesis and disrupt iron metabolism [25].

Advancing age was identified as a significant risk factor for anemia. Choi et al. reported an increased prevalence of anemia among elderly individuals, which may be attributed to nutritional deficiencies, chronic inflammation, bone marrow dysfunction, and multiple comorbidities [24]. Diabetes further exacerbates these age-related changes, increasing the risk of anemia.

Anemia in diabetic patients has serious clinical implications. Bosman et al. demonstrated that anemia occurs early in diabetic nephropathy and is associated with erythropoietin deficiency [10]. Keane and Lyle reported that reduced hemoglobin levels are associated with increased hospitalization and premature mortality in diabetic patients [11]. Therefore, early detection and management of anemia may improve outcomes and reduce the burden of diabetic complications.

CONCLUSION

Anemia is a prevalent and clinically significant condition among patients with type 2 diabetes mellitus, particularly among females, elderly individuals, and those with poor glycemic control. Routine screening for anemia should be incorporated into standard diabetes management. Early diagnosis, nutritional supplementation, and optimal glycemic control may reduce anemia-related morbidity and improve quality of life in diabetic patients.

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