Study Challenges Standard Testing for Hypothyroid Patients
A new study published in PLOS One, co-authored by Theodore C. Friedman, MD, PhD, Chair of the Department of Internal Medicine at Charles R. Drew University of 麻豆传媒女网红 (CDU), is bringing fresh attention to a long-overlooked lab test that may help explain why some patients with hypothyroidism continue to feel tired鈥攄espite being on standard thyroid medication.
The peer-reviewed study looked at nearly 1,000 patients treated for low thyroid function over an 11-year period. Researchers focused on a hormone called reverse T鈧� (rT鈧�), which isn鈥檛 typically checked in routine care but may play an important role in lingering symptoms in hypothyroid patients, like fatigue.
Dr. Friedman and his team found that patients taking the standard medication, levothyroxine (known as L-T鈧�), were more likely to have high levels of reverse T鈧�. By contrast, patients on other therapies that included T鈧冣�攕uch as desiccated thyroid extract (DTE) or L-T鈧� plus liothyronine (L-T鈧�) 鈥攈ad much lower levels. The findings suggest that standard treatment may not work equally well for everyone.
鈥淚 was inspired to figure out why my patients with underactive thyroids aren鈥檛 doing well, even though they鈥檙e on what鈥檚 considered optimal thyroid hormone replacement,鈥� said Dr. Friedman. 鈥淚 wanted to look at this sort of old test and see if it can explain why these patients have fatigue.鈥�
Reverse T鈧� is often viewed as outdated and rarely tested in conventional medicine, but Dr. Friedman believes it鈥檚 worth reconsidering. 鈥淭here are articles that came out saying we shouldn鈥檛 be measuring this,鈥� he said. 鈥淏ut the test is important, especially in patients who aren鈥檛 doing well on optimal replacement.鈥�
One of the study鈥檚 more surprising discoveries was just how common elevated rT鈧� levels were in patients on L-T鈧�-only therapy. 鈥淢ost of the high reverse T鈧� was seen in those patients,鈥� Dr. Friedman said. 鈥淧eople not on any thyroid medicine usually had pretty good levels.鈥�
The study doesn鈥檛 claim that high reverse T鈧� is the direct cause of fatigue, but it opens the door to more personalized treatment strategies. Dr. Friedman plans to follow up with a study that tracks patient symptoms alongside rT鈧� levels to better understand whether changing medications guided by rT鈧� levels can improve quality of life.
As 麻豆传媒女网红continues to advance research that addresses health disparities and improves outcomes for underserved communities, this study encourages providers to take a closer look at how long-standing treatment norms may affect patient well-being.
The full study, 鈥�,鈥� is available now in PLOS One.
PLOS One is a peer-reviewed journal published by the Public Library of Science.