A doctor diagnoses mild, or subclinical, hypothyroidism through a medical history and physical examination. If your doctor suspects that you have subclinical hypothyroidism, you will have lab tests to confirm the diagnosis.
Subclinical hypothyroidism is diagnosed when you have:
- No symptoms or mild symptoms of hypothyroidism. Examples are fatigue, cold intolerance, consistent weight gain, depression, or memory problems.
- A mildly high thyroid-stimulating hormone (TSH) level.
- A normal thyroxine (T4) level.
Some studies have shown that older adults with subclinical hypothyroidism may be more likely to have heart failure. But more research is needed.
Research does not provide clear evidence to support treatment of every person who has subclinical hypothyroidism. And many doctors disagree whether it should be treated. When making the decision to treat subclinical hypothyroidism, you and your doctor will talk about the benefits of treatment (reduced symptoms) compared to the cost of medicine and monitoring symptoms. Some studies have shown that treatment of subclinical hypothyroidism may lower cholesterol levels. But more research is needed.
Current as of: March 31, 2020
Author: Healthwise Staff
Kathleen Romito MD - Family Medicine
Brian D. O'Brien MD - Internal Medicine
E. Gregory Thompson MD - Internal Medicine
Adam Husney MD - Family Medicine
Matthew I. Kim MD - Endocrinology