Investigation of Hemoglobin, Iron, Ferritin, and Vitamin B12 Levels in Patients with Primary Hypothyroidism

Abstract

Objective: This study aimed to investigate the effects of hypothyroidism on hemoglobin, vitamin B12, iron, total iron-binding capacity (TIBC), ferritin, and mean corpuscular volume (MCV), and to evaluate the relationships between these parameters and thyroid-stimulating hormone (TSH), free thyroxine (fT4), and thyroid peroxidase antibody (anti-TPO) levels. Method: This retrospective and descriptive study was conducted by reviewing the digital medical records of patients who presented to the Family Medicine Outpatient Clinic of the University of Health Sciences Ankara Atatürk Sanatoryum Eğitim ve Araştırma Hastanesi between September 1, 2020, and September 1, 2022. A total of 200 patients diagnosed with hypothyroidism and 200 euthyroid individuals were included based on thyroid function test results. Demographic data including age, sex, and comorbid conditions were recorded. Laboratory parameters including TSH, fT4, anti-TPO, hemoglobin, vitamin B12, MCV, iron, TIBC, and ferritin levels were analyzed. Data analysis was performed using SPSS version 25.0. Results: A total of 342 females and 58 males were included in the study. The mean age was 44.95 ± 12.52 years. TSH, anti-TPO, and TIBC levels were significantly higher, while fT4, hemoglobin, vitamin B12, MCV, iron, and ferritin levels were significantly lower in the hypothyroid group compared to the euthyroid group (p<0.001). Positive correlations were observed between fT4 and hematologic parameters, whereas TSH and anti-TPO showed negative correlations. Conclusions: Hematological changes associated with anemia and vitamin B12 deficiency have been observed in patients with hypothyroidism. Therefore, regular monitoring of iron and vitamin B12 levels in these patients is important for early diagnosis and treatment.

Keywords

• hypothyroidism
• anemia
• iron deficiency
• vitamin b12

Primer Hipotiroidi Hastalarında Hemoglobin, Demir, Ferritin ve B12 Değerlerinin İncelenmesi

Abstract

Amaç: Bu çalışmada, hipotiroidinin hemoglobin, B12 vitamini, demir, toplam demir bağlama kapasitesi (DBK), ferritin ve ortalama eritrosit hacmi (MCV) üzerindeki etkileri ile bu parametrelerin tiroid stimülan hormon (TSH), serbest tiroksin (sT4) ve tiroid peroksidaz antikoru (anti-TPO) düzeyleriyle ilişkileri değerlendirilmiştir. Yöntem: Bu çalışma, retrospektif ve tanımlayıcı bir araştırma olarak planlanmış olup, 1 Eylül 2020 ile 1 Eylül 2022 tarihleri arasında Sağlık Bilimleri Üniversitesi Ankara Atatürk Sanatoryum Eğitim ve Araştırma Hastanesi Aile Hekimliği Polikliniği’ne başvuran hastaların dijital tıbbi kayıtları incelenerek gerçekleştirilmiştir. Çalışmaya, tiroid fonksiyon testlerine göre hipotiroidi tanısı almış 200 hasta ile tiroid fonksiyonları normal olan 200 ötiroid birey dâhil edilmiştir. Katılımcıların yaş, cinsiyet ve eşlik eden hastalık bilgileri kaydedilmiş; TSH, sT4, anti-TPO, hemoglobin, B12 vitamini, MCV, demir, DBK ve ferritin düzeyleri değerlendirilmiştir. Veriler SPSS 25.0 programı ile analiz edilmiştir. Bulgular: Çalışmaya 342 kadın ve 58 erkek birey dâhil edilmiştir. Yaş ortalaması 44.95 ± 12.52 yıl olarak hesaplanmıştır. Hipotiroidi hastalarında TSH, anti-TPO ve DBK düzeyleri anlamlı şekilde yüksek; sT4, hemoglobin, B12, MCV, demir ve ferritin düzeyleri anlamlı şekilde düşük bulunmuştur (p<0.001). sT4 ile hematolojik parametreler arasında pozitif; TSH ve anti-TPO ile negatif korelasyon saptanmıştır. Sonuç: Hipotiroidi hastalarında anemi ve B12 eksiklikleriyle ilişkili hematolojik değişiklikler gözlenmiştir. Bu nedenle, bu hastaların demir ve B12 düzeylerinin düzenli aralıklarla izlenmesi erken tanı ve tedavi açısından önem taşımaktadır.

Keywords

• hipotiroidizm
• anemi
• demir eksikliği
• b12 vitamini

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