麻豆传媒

Compared with primary care physicians, specialists were more likely to order unnecessary thyroid ultrasonography, according to a new study.

In a survey of over 600 physicians, many physicians ordered thyroid ultrasound for clinically unsupported reasons conflicting with , including for positive thyroid antibodies (23%), abnormal thyroid function tests results (28%), or simply at the patient's request (33%), reported Debbie Chen, MD, of the University of Michigan in Ann Arbor, and colleagues.

As shown in the team's research letter online in , specialists were more than two times as likely as primary care physicians to order thyroid ultrasound at the patient's request -- a clinically unsupported reason for ultrasound:

• Endocrinologists: OR 2.46 (95% CI 1.22-4.97)

• Otolaryngologists: OR 2.87 (95% CI 1.49-5.54)

• General surgeons: OR 2.20 (95% CI 1.19-4.06)

Calling the findings "alarming," senior study author Megan Haymart, MD, also of the University of Michigan in Ann Arbor, told 麻豆传媒: "Since the specifically recommends against ordering thyroid ultrasounds for abnormal thyroid function tests, we were especially surprised by this finding."

On the other hand, she said, the team was reassured that the vast majority of physicians in the study did appropriately order thyroid ultrasounds for clinically supported reasons. These included palpable thyroid nodules on an examination (98%), large goiter (92%), nodules seen on another imaging test (88%), and new-onset hoarseness or compressive symptoms (66%).

"We also found that no physician endorsed use for routine well-patient visits," Haymart added.

She emphasized the importance of physicians avoiding ordering thyroid ultrasound for clinically unsupported reasons: "Unnecessary testing can lead to a diagnosis of indolent disease," she explained, pointing out that greater use of thyroid ultrasound has also been attributed to the rise in the incidence of . "This can result in a treatment cascade, with some patients at risk for harm," Haymart added.

For the study, the researchers administered the survey to 134 surgeons, 130 otolaryngologists, 176 endocrinologists, and 162 primary care physicians between 2018 and 2019. All providers were involved in thyroid cancer care in the Surveillance, Epidemiology, and End Results registries in Georgia and Los Angeles.

While about 70% of the respondents said they had read either the or the , only about 18% read both sets of guidelines, and far more read the 2015 ATA guidelines alone.

In addition, about 70% of the respondents cited published clinical guidelines as the most influential factor in decision-making for treating patients with thyroid nodules or cancer -- more influential than meetings, other experts, training, colleagues, journal articles, or employer guidelines.

Interesting though, those who didn't read any guidelines were not any more likely to schedule a clinically unsupported thyroid ultrasound for their patient (OR 1.19, 95% CI 0.67−2.10), the researchers reported.

They also found that compared with physicians at an academic medical center, those in private practice were far more likely to schedule ultrasonography exams for the clinically unsupported reasons of abnormal thyroid function test results (OR 2.45, 95% CI 1.28-4.69) or positive thyroid antibody test results (OR 2.61, 95% CI 1.28-5.32).

The volume of patients with thyroid nodules also influenced provider decision-making as well, the investigators noted, explaining that physicians who managed 10 or fewer patients with these nodules each year were significantly less likely to order an ultrasound for positive thyroid antibody test results compared with providers who cared for 50 or more such patients a year (OR 0.41, 95% CI 0.18-0.93).

Study limitations, the researchers said, included a lack of information regarding patient requests for ultrasonography, and that physicians were not asked if they themselves performed the thyroid ultrasonography examinations.

"Despite limitations, this study highlights the need for focused physician education on clinically supported and unsupported indications for use of thyroid ultrasonography, with potential roles for future clinical practice guidelines, patient decision-making aids, and clinical decision-making support tools," Chen, Haymart, and co-authors concluded.

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