A little bit of scientific comment and analysis to discriminate plausible papers from rubbish.
In the latest journal Thyroid I've picked out a paper that could mislead readers in its misuse of statistical analyses These are the kind of sloppy papers that all too easily get picked on as support for a particular belief. The almost laughable part is to find probabilities of 0.049 and 0.025 in their estimation of heart attack and stroke as being significant. It's generally accepted that probabilities greater than 0.01 are of doubtful significance and greater than 0.05 as being insignificant. Now the above numbers are either of marginal and uncertain significance or of no meaningful significance at all. Note the confidence limits almost reach 1.000 (ie insignificant). Also note that T3 users were mixed in as combined therapy and T3 only. I have just posted this "paper" as a fine example of publishing bad work and worse, getting the esteemed journal Thyroid to accept it.
ThyroidVol. 32, No. 7
Heart Failure and Stroke Risks in Users of Liothyronine With or Without Levothyroxine Compared with Levothyroxine Alone: A Propensity Score-Matched Analysis
Wook Yi, Bo Hyun Kim, Mijin Kim, Jinmi Kim, Myungsoo Im, Soree Ryang, Eun Heui Kim, Yun Kyung Jeon, Sang Soo Kim, and In Joo Kim
Published Online:8 Jul 2022Methods: We conducted a retrospective multicenter study across four hospital databases encoded in the Observational Medical Outcomes Partnership (OMOP) CDM. LT3 users were defined as those who received an LT3 prescription for at least 90 days (with or without LT4), and their safety outcomes were compared with those in LT4-only users after 1:4 propensity score matching. Safety outcomes included the incidences of osteoporosis, cardiovascular disease, cancer, anxiety disorder, and mood disorder.
Results: We identified 1434 LT3 users and 3908 LT4-only users. There was a statistically significant difference in the incidence rate of safety outcomes between LT3 users and LT4-only users. The risks of heart failure (incidence rate ratio [IRR] = 1.664, 95% confidence interval [95% CI] 1.002–2.764, p = 0.049) and stroke (IRR = 1.757, CI 1.073–2.877, p = 0.025) were higher in LT3 users than in LT4-only users. When subgroup analysis was performed according to the presence/absence of thyroid cancer history and duration of thyroid hormone replacement, the risk of heart failure was higher in LT3 users with a history of thyroid cancer and those who underwent ≥52 weeks of LT3 therapy. In addition, the risk of stroke was higher in LT3 users without thyroid cancer history and those who underwent ≥52 weeks of LT3 therapy.
Conclusions: The use of LT3 was associated with increased incidence of heart failure and stroke in patients with a longer duration of LT3 use and history of thyroid cancer. Therefore, clinicians should consider the risk of heart failure and stroke in thyroid cancer patients with long-term use of LT3. These findings require confirmation in other populations.
Dear me!