Down Syndrome Thyroid Treatment Study


About The Study

In addition to the Metabolic Health study, we are also conducting the Down Syndrome Thyroid Treatment Study. This is a separate study investigating treatment of subclinical hypothyroidism (SCH) in children and adolescents with Down syndrome. We are looking for 40 children and adolescents between the ages of 8-20 with both Down syndrome and SCH to participate. This study is also recruiting from both the Children's Hospital of Philadelphia (CHOP) and Children's National Medical Center (CNMC), and study visits can take place at either CHOP or CNMC.

Why is it important?

Subclinical hypothyroidism means that your body's level of thyroid stimulating hormone (TSH) is above normal, but you likely do not have symptoms of hypothyroidism. Studies have shown that adults with SCH are at increased risk for developing type 2 diabetes and heart problems. SCH is common in DS, but it is unknown whether treatment of SCH in Down Syndrome is beneficial.

Through this study, we hope to learn more about whether treating SCH will result in any changes to the cardiometabolic health of children and adolescents with DS. This information may help medical providers decide how to manage SCH in children and adolescents with DS.

Participant in CHOP Scrubs

What does the study involve?

If you agree to take part, your participation may last for up to 18 months and will involve 1 research visit every 6 months (up to 4 research visits) at either CNMC's or CHOP's main hospital. The study also involves 3 blood draw visits that can be done at the main hospital of either site, or at a CHOP or CNMC satellite location that is convenient to you.

Your child will be asked to take medication for one year. During the first 6 months, your child will receive either levothyroxine (an active medication), or a placebo. In the final 6 months, all participants will receive levothyroixine.

You and your child will be compensated for each research visit and each blood draw visit that you complete.



Study participant is measured for height

The following procedures will be completed during each research visit at either CHOP or CNMC Main:

  • Fasting blood and urine samples — we will collect a lipid panel, thyroid levels and hemoglobin A1C
  • A DXA scan (an X-Ray that looks at bone, muscle, and fat mass)
  • A physical exam done by one of our study physicians
  • Body measurements
  • Parent and child questionnaires
  • Ultrasounds — limited echocardiogram and pulse-wave velocity * will only be done at the first research visit.

You may need to have bloodwork done between visits to the main hospital to assess your thyroid hormone levels. These can be done at a CHOP or CNMC affiliated lab closer to you.

After each research visit:

  • Your child will wear a physical activity armband (provided by the research team) for 7 days.
  • A nutritionist will contact you 3 times to record what your child has eaten in the past day.

See if your child is eligible for the study!

If you would like more information, please take a look at our study flyer! You can download a PDF of it by clicking on the picture below:

  • Males and females aged 8 – 20 years
  • Diagnosis of Down syndrome
  • Subclinical hypothyroidism: TSH between 5-10 mIU/L
  • Pregnancy
  • Type 1/Type 2 Diabetes
  • Chronic medical conditions or medication use that can affect growth, nutrition, blood sugar, insulin, or thyroid function (such as lithium or certain seizure medications)
  • Current use of thyroid hormone medication or anti-thyroid hormone
  • Cyanotic congenital heart disease and/or pulmonary hypertension

*Many factors are considered when determining an individual's eligibility, so while the above should serve as a general guideline, please contact the study team to review your child's eligibility in further detail and determine whether he or she is able to participate in the study.

Additional Study Resources