Normal thyroid function values in Ethiopians

Area of Science:

• Endocrinology
• Public Health
• Clinical Chemistry

Background:

• Establishing accurate reference ranges for thyroid function tests is crucial for diagnosing thyroid disorders.
• Previous studies have not comprehensively defined thyroid function parameters specifically for the Ethiopian adult population.

Purpose of the Study:

• To determine normal reference values for thyroid hormones and radioactive iodine uptake in healthy adult Ethiopians.
• To compare these values with those established in developed countries and investigate potential influencing factors.
• To provide a basis for the rational interpretation of thyroid function tests in Ethiopian patients.

Main Methods:

• Measurement of serum triiodothyronine (T3), thyroxine (T4), and thyrotropin (TSH) levels in 56 healthy adult Ethiopians (20 males, 36 females).
• Assessment of radioactive iodine uptake (RAIU) at 2 and 24 hours.
• Statistical analysis to determine mean values, standard deviations, and significance of differences between sexes.

Main Results:

• Mean T3 values were 1.42 +/- 0.32 nmol/L (males) and 1.51 +/- 0.25 nmol/L (females).
• Mean T4 values were 119 +/- 22 nmol/L (males) and 116 +/- 21 nmol/L (females).
• Mean TSH values were identical for both sexes at 1.85 +/- 0.94 mu/L.
• RAIU at 24 hours was significantly higher in females (38.9 +/- 11.1%) than males (31.7 +/- 11.7%) (P < 0.05).
• Ethiopian RAIU values were higher than those typically observed in developed countries, suggesting lower dietary iodine intake.

Conclusions:

• The study provides essential reference ranges for thyroid function tests in adult Ethiopians.
• Elevated RAIU in Ethiopians may indicate endemic iodine deficiency.
• These reference values are critical for accurate diagnosis and management of thyroid disorders in Ethiopia.