When reading medical “news items”, CAVEAT EMPTOR!
My newsfeed
My medical newsfeed is a wonderful thing: – One of these days, I really must calculate the (factual, vs. careless-ignorance-based) error rate!
This time, I received a missive from Medscape Medical News, authored by Karon Warren, a freelance journalist living in Georgia: the report details the findings of a study, in JAMA Internal Med., Published online October 23, 2023, entitled
“Be Advised: Thyroid Hormones May Increase Risk of Cognitive Disorders in Older Adults” (again, as often happens, this message fails the test of “news”: it’s dated November 02, 2023).
Let’s restate the title:
”Thyroid Hormones May Increase Risk of Cognitive Disorder in Older Adults”
It begins with “Patients age 65 and older who receive thyroid hormone therapy and experience “low thyrotropin” (TSH) are at increased risk for dementia and other cognitive problems, according to new research published October 23 in JAMA Internal Medicine.
It reports on IATROGENIC Thyrotoxicosis (see BOLD type, below)
“The study found that patients with thyrotoxicosis had a higher likelihood of incident cognitive disorder (adjusted hazard ratio (aHR), 1.39; 95% CI, 1.18 – 1.64; P < .001). Broken down between internal and external causes of thyrotoxicosis, exogenous thyrotoxicosis continued to be a significant risk factor (aHR, 1.34: 95% CI, 1.10 – 1.63; P = .003), while endogenous thyrotoxicosis did not show a statistically significant risk (aHR, 1.38; 95% CI, 0.96 – 1.98; P = .08).”
It states that females are more likely to show low TSH levels
“The study also found that women were more likely to have low levels of thyrotropin (thyroid-stimulating hormone/TSH) than men and were more likely to be overtreated.”
Then, in what seems to be an oxymoron, it says that “the signal” is present in both iatrogenic and endogenous hyperthyroidism:
“Previous studies looking at the correlation between hyperthyroidism and cognitive disorders often did not include participants who were already taking thyroid hormones, according to Jennifer S. Mammen, MD, PhD, assistant professor of medicine at the Asthma and Allergy Center at John Hopkins University School of Medicine in Baltimore and the senior author of the study” …… “The fact that we see the signal both in people who are being overtreated with thyroid hormone and in people who have endogenous hyperthyroidism is one way that we think that this supports the fact that it’s not just confounding, it’s not just bias”, Mammen said. “There’s two different sources of hyperthyroidism, and they’re both showing the same relationship.”
The study concluded that perhaps, older patients did not need treatment for their hypothyroidism
Mammen and colleagues analyzed electronic health records for patients aged 65 years and older who received primary care in the Johns Hopkins Community Physicians Network over a 10-year period starting in 2014. None had a history of low TSH levels or cognitive disorder diagnoses within 6 months of their first doctor visit.
More than 65,000 patients were included: 56% were female. Of 25,000 low TSH measurements in 2,710 patients, iatrogenic TSH comprised 14,875, endogenous TSH numbered 4,159 and those of “unknown cause“ totalled 5,833.
During the follow-up period, 7.2% (4779) patients received a new cognitive disorder diagnosis, which was dementia in 77% of cases.
Mammen concluded that primary care physicians should “carefully consider whether thyroid hormone therapy is necessary for older patients” and take great care to avoid overtreatment, saying “This is yet another reason for us to be vigilant about not overtreating people with thyroid hormone, especially in older adults. We already know that atrial fibrillation rates are increased in people who are hyperthyroid. We know that fracture and osteoporosis is affected by hyperthyroidism. And now we also have an association with higher rates of cognitive disorders.”
This report was taken seriously
According to Medscape, Jean Chen, MD, partner at Texas Diabetes & Endocrinology, who was not affiliated with the study, said “All medical providers need to be aware that the 65 and older population does not need to be treated as aggressively with their thyroid hormone. We are finding more and more complications from overtreatment, rather than benefit, in this population.”
Chen continued:
“Often, older patients may complain of symptoms such as constipation, feeling cold, or tiredness, which can be symptoms of hypothyroidism. But these symptoms could also be from anemia, vitamin deficiencies, depression, perimenopause, menopause, insulin resistance, and sleep apnea. If necessary, Chen recommends primary care physicians consult with an endocrinologist regarding a possible treatment plan and making a differential diagnosis.” ……………….
The symptoms mentioned are definitely those of hypothyroidism! – G. A. Harry
In addition, Chen said other studies have shown that treating patients with “Thyroid Hormone” (she means T4) either did not resolve the condition, or negatively impacted anxiety, muscle strength, and bone density, or it increased the risk for arrhythmia.
She concluded: “Therefore, it’s important to weigh the risks vs the benefits.”
This study was amply supported
The study was supported by the Richman Family Precision Medicine Center of Excellence in Alzheimer’s Disease, the Richman Family Foundation, the Rick Sharp Alzheimer’s Foundation, the Sharp Family Foundation, among others. The work was also supported by grants from the National Institutes of Health.
Also, Co-author Constantine Lyketsos, MD, MPH, reports personal fees from Karuna, MapLight Therapeutics, Axsome Therapeutics, GIA, GW Research Limited, Merck, EXCIVA GmbH, Otsuka, IntraCellular Therapies, and Medesis Pharma for consulting for treatment development in Alzheimer’s disease outside the submitted work. No other disclosures were reported………………. isn’t that interesting?
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