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Vitamin B12 deficiency common in primary hypothyroidism
Abdul Jabbar1, Aasma Yawar, Sabiha Waseem
1Department of Medicine, Aga Khan University, Karachi, Pakistan.
JPMA. the Journal of the Pakistan Medical Association
|July 29, 2008
Summary
Nearly 40% of hypothyroid patients have vitamin B12 deficiency. Screening all hypothyroid patients for vitamin B12 levels is recommended, as deficiency impacts symptoms and response to treatment.
Area of Science:
- Endocrinology
- Nutritional Science
- Hematology
Background:
- Hypothyroidism is a common endocrine disorder.
- Vitamin B12 deficiency can present with nonspecific symptoms.
- The relationship between hypothyroidism and vitamin B12 deficiency requires further investigation.
Purpose of the Study:
- To determine the prevalence of vitamin B12 deficiency in hypothyroid patients.
- To identify clinical features associated with vitamin B12 deficiency in this population.
- To evaluate the efficacy of vitamin B12 replacement therapy on symptoms.
Main Methods:
- 116 hypothyroid patients were assessed for vitamin B12 deficiency.
- Laboratory tests included hemoglobin, MCV, vitamin B12 levels, and anti-thyroid antibodies.
- Patients with low B12 levels received monthly intramuscular vitamin B12 injections.
Main Results:
- 39.6% of hypothyroid patients exhibited vitamin B12 deficiency.
- Symptoms like weakness, memory impairment, and depression were more common in deficient patients but not statistically significant.
- Vitamin B12 replacement therapy led to symptom improvement in 58.3% of deficient patients.
Conclusions:
- A high prevalence of vitamin B12 deficiency exists in hypothyroid patients.
- Clinical symptoms are unreliable indicators for diagnosing vitamin B12 deficiency.
- Universal screening for vitamin B12 is advised for hypothyroid patients, regardless of antibody status.
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