Imagine going for a routine checkup. Your doctor tests your thyroid function. You have no thyroid disease symptoms. However, your TSH blood level is above normal. Your T4 level is normal. These results indicate mild hypothyroidism, also called sub-clinical. It doesn’t meet criteria for overt hypothyroidism. This causes disagreement among doctors about using medication.
The importance of this issue is huge. Many people are diagnosed with sub-clinical thyroid disease. Studies show up to 20% of women over sixty have it. Also, 4% to 8.5% of the general population are affected.
Treatment guidelines for sub-clinical hypothyroidism
Treatment guidelines for sub-clinical hypothyroidism vary. Primary care doctors face inconsistent advice. Confusion leads to debates on routine screening. Opponents argue against screening everyone. They prefer testing people with symptoms or risk factors. Screening uncovers many mild cases. These cases might not need or benefit from treatment.
Some subclinical hypothyroidism cases don’t become overt disease. Only 2.6% without anti-TPO antibodies progress each year. The risk is higher for those with antibodies; 4.6% progress yearly.
Overtreatment carries risks too. People may develop thyrotoxicosis, or “toxic thyroid.” Long-term complications include heart issues and bone loss. Most doctors agree that symptomatic patients may benefit from hormone replacement. However, this isn’t proven, and asymptomatic patients pose a challenge.
Some research suggests treating mild disease to prevent untreated consequences. These include high cholesterol, heart disease, psychiatric problems, and overt hypothyroidism risk.
In 2000, Dutch researchers studied 1,149 women aged 55 and older. They recommended treatment after finding a link between sub-clinical hypothyroidism, aortic atherosclerosis, and heart attack history.
Heart disease prevalence was highest in women with subclinical disease and anti-TPO antibodies. The study reported subclinical hypothyroidism as a risk factor for heart disease, comparable to high cholesterol, smoking, hypertension, and diabetes.
Sub-Clinical Hypothyroidism Report in JAMA
In order to reach agreement on subclinical disease management, a large group of endocrinologists took action. Sponsored by the ATA, AACE, and the Endocrine Society, they compiled recommendations for primary care doctors. These were based on a thorough review of all the relevant published research.
In 2004, their report was published in the Journal of the American Medical Association (JAMA). The panel investigated and found something interesting. They discovered that the research linking mild hypothyroidism to heart issues was often flawed or inconclusive.
Specifically, the Rotterdam study was brought into question. It failed to establish a cause-effect link between mild hypothyroidism and aortic atherosclerosis. There could be other explanations for the results, the panel noted. For instance, lifestyle factors and healthcare accessibility may be to blame.
Moreover, the panel did not find compelling evidence to support treatment of mild hypothyroidism. They found no strong proof that such treatment alleviates symptoms or prevents the progression to full-blown disease.
Who should be treated for mild disease? It depends on individual circumstances. One factor is the severity of mild disease.
If your TSH falls between 4.5 and 10 mU/L, with a normal T4, treatment isn’t advised. However, regular monitoring is crucial. Expect checks every 6 to 12 months. For reference, Table 4.1 shows normal blood test ranges.
In contrast, if your TSH exceeds 10 mU/L, your condition is mild with normal T4. Yet, the risk of overt disease increases significantly. Consequently, the panel deems treatment reasonable for this group.
Particularly, pregnant women require focused care. Indeed, mild hypothyroidism could harm fetal brain development. Therefore, treating pregnant women with mild hypothyroidism is recommended. However, universal screening is not suggested.
They suggest testing pregnant women with thyroid disease history, autoimmune disorders, or thyroid disease signs and symptoms.
Consensus
The consensus panel doesn’t advise routine screening for everyone. It lacks evidence for preventative benefits. However, it recommends checking high-risk individuals, including women over 60. The U.S. Preventive Services Task Force supported this in a 2004 report, finding insufficient evidence for routine screening.
These reports aren’t the final word. The AACE, a cosponsor, disagrees with the panel. It maintains its 2002 recommendations to treat patients with TSH over 5 mU/L if goiter or antibodies are present. The consensus panel doesn’t advise antibody testing for mild disease.
The AACE warns against relying only on studies and ignoring clinical experience. They suggest physicians decide on treatment after a thorough history and physical examination of the patient.
Firstly, you should know that thyroid disease evaluations are not common. Additionally, routine screenings are not recommended for the general population. Therefore, it’s crucial that you take action. Specifically, you may need to request a thyroid function test. This is important if you are experiencing symptoms. Similarly, it’s vital if you are at risk for thyroid disease.
