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Reduced thyrotropin in euthyroid goitrous patients suggesting subclinical hyperthyroidism
E K Chuhwak1, F I Anjorin, A E Ohwovoriole
1Department of Medicine, Jos University Teaching Hospital, Jos. kchuhwak@yahoo.com
Summary
Subclinical hyperthyroidism, characterized by low thyroid-stimulating hormone (TSH) with normal thyroxine (T4) and triiodothyronine (T3) levels, affects 7.9% of euthyroid goiter patients over 60. Early detection is crucial due to associated cardiovascular risks.
Area of Science:
- Endocrinology
- Thyroidology
- Internal Medicine
Background:
- Subclinical hyperthyroidism (low TSH, normal T4/T3) often presents without symptoms.
- It can lead to cardiovascular abnormalities like atrial fibrillation and diastolic dysfunction.
- Treatment may mitigate cardiovascular progression.
Purpose of the Study:
- To determine the prevalence of subclinical hyperthyroidism.
- To highlight the importance of recognizing this often-overlooked condition.
Main Methods:
- Hospital-based study at Jos University Teaching Hospital.
- Consecutive clinically euthyroid goiter patients were assessed.
- Thyroid hormone levels (TSH, T4, T3) measured using ELISA techniques.
Main Results:
- Prevalence of subclinical hyperthyroidism was 7.9% (7 out of 89 analyzed patients).
- Affected individuals were predominantly over 60 years old.
- Long-standing goiter was common among those with subclinical hyperthyroidism.
Conclusions:
- Endogenous subclinical hyperthyroidism affects 7.9% of clinically euthyroid goiter patients, particularly those over 60 with long-standing goiter.
- The high prevalence necessitates a high index of suspicion.
- This condition is linked to morbidities that can increase mortality.
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