Is a thyroid stimulating hormone greater than 5 hypothyroidism

Thyroid stimulating hormone TSH greater than 5mIU/L usually indicates hypothyroidism, but it needs to be comprehensively judged in combination with free thyroxine FT4 levels. The main influencing factors include primary hypothyroidism, subclinical hypothyroidism, pituitary TSH tumors, abnormal iodine intake, and detection errors.

1. Primary hypothyroidism:

Thyroid disease itself leads to insufficient hormone secretion and compensatory increase in TSH. Common causes include Hashimoto's thyroiditis, thyroid surgery or radiation therapy, and typical symptoms include chills, fatigue, and weight gain. Further diagnosis is required through thyroid antibody testing and ultrasound.

2. Subclinical hypothyroidism:

TSH is slightly elevated by 5-10mIU/L but FT4 is normal, which belongs to the early stage of hypothyroidism. About 5% of patients will progress to clinical hypothyroidism, especially those with positive thyroid peroxidase antibodies have a higher risk. It is recommended to have thyroid function rechecked every 6-12 months.

3. Pituitary TSH Tumor:

In rare cases, pituitary tumors secrete TSH abnormally, leading to an increase in detection values. Often accompanied by hyperthyroidism symptoms such as thyroid enlargement and tachycardia, it needs to be differentiated through pituitary MRI and thyroid stimulating hormone releasing hormone test.

4. Abnormal iodine metabolism:

Iodine deficiency or excess can interfere with thyroid hormone synthesis and cause TSH fluctuations. Long term high iodine diet, use of iodine containing drugs, or living in iodine deficient areas require targeted screening and, if necessary, urinary iodine concentration testing.

5. Detection of interfering factors:

Sample hemolysis, heterophilic antibodies, and use of biotin supplements may lead to false TSH elevation. It is recommended to have a fasting check-up in the morning, stop using biotin for at least 72 hours before retesting, and compare different testing methods if necessary.

If TSH elevation is found, a complete set of thyroid function tests should be conducted, including FT3, FT4, TPOAb and other indicators. Pay attention to controlling iodine intake in daily life and avoid excessive consumption of high iodine foods such as seaweed and seaweed; Regular sleep schedule reduces the risk of autoimmune attacks; Pay attention to keeping warm in winter, as hypothyroidism patients have a lower metabolic rate and are more prone to fear of cold. For pregnant women, it is recommended to control TSH levels below 2.5mIU/L. Diagnosed patients should adjust their levothyroxine dosage according to medical advice and regularly monitor to avoid drug overdose leading to osteoporosis or arrhythmia.