Hypothyroidism: Diagnosis and Treatment.

Area of Science:

• Endocrinology
• Internal Medicine

Background:

• Hypothyroidism affects 1 in 300 individuals, with higher prevalence in women and older adults.
• Symptoms are nonspecific, including fatigue, weight gain, and cold intolerance, ranging from mild to life-threatening myxedema coma.
• Diagnosis depends on thyroid-stimulating hormone (TSH) and free thyroxine (fT4) blood levels.

Purpose of the Study:

• To outline the diagnosis and management of clinical hypothyroidism.
• To provide guidance on levothyroxine replacement therapy and special considerations for specific patient populations.
• To emphasize the importance of early recognition of severe complications like myxedema coma.

Main Methods:

• Diagnosis based on blood tests: thyroid-stimulating hormone (TSH) and free thyroxine (fT4).
• Treatment with levothyroxine (LT4) at 1.5-1.8 mcg/kg/day for symptom relief and TSH normalization.
• Dosage adjustments for patients over 60, those with ischemic heart disease, and pregnant women.

Main Results:

• Levothyroxine therapy is effective for symptom relief and normalizing TSH levels.
• Adding triiodothyronine is not recommended for persistent symptoms with normal TSH.
• Subclinical hypothyroidism generally does not require treatment unless TSH > 10 mIU/L or thyroid peroxidase antibodies are elevated.

Conclusions:

• Levothyroxine is the standard treatment for hypothyroidism, with careful titration based on patient factors.
• Population screening for hypothyroidism is not evidence-based.
• Prompt management of myxedema coma is critical.