The long-term prognostic implications of free triiodothyronine to free thyroxine ratio in patients with obstructive sleep apnea and ACS

[helvella]

Another paper reporting FT3/FT4 ratio as a relevant factor. In this case, wiuth quite serious implications of have a low value.

Front Endocrinol (Lausanne). 2024 Sep 16:15:1451645.

doi: 10.3389/fendo.2024.1451645. eCollection 2024.

The long-term prognostic implications of free triiodothyronine to free thyroxine ratio in patients with obstructive sleep apnea and acute coronary syndrome

Yun Zhou # 1 2 3 , Qian He # 1 2 3 , Hui Ai 1 2 3 , Xuedong Zhao 1 2 3 , Xiuhuan Chen 1 2 3 , Siyi Li 1 2 3 , Zekun Zhang 1 2 3 , Jingyao Fan 1 2 3 , Wei Gong 1 2 3 4 , Shaoping Nie 1 2 3

PMID: 39351531 PMCID: PMC11439673 DOI: 10.3389/fendo.2024.1451645

Abstract

Objective: Obstructive sleep apnea (OSA) and thyroid dysfunction frequently overlap clinically and are risk factors for cardiovascular disease. The free triiodothyronine to free thyroxine (FT3/FT4) ratio as a novel biomarker of cardiovascular disease prognosis, but the impact of the FT3/FT4 ratio on the prognosis of OSA in patients with acute coronary syndromes (ACS) remains uncertain.

Methods: In this prospective cohort study, 2160 patients with ACS were recruited and underwent portable sleep monitoring at Beijing Anzhen Hospital from June 2015 to January 2020. OSA was diagnosed when apnea-hypopnea index of ≥15 events/h. Patients were further divided into tertiles according to FT3/FT4 ratio. All patients had scheduled follow-up visits at 1, 3, 6, 9 and 12 months after discharge, with subsequent outpatient visits or telephone follow-up visits every 6 months. The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE), including cardiovascular death, myocardial infarction (MI), stroke, ischemia-driven revascularization, or hospitalization for unstable angina or heart failure.

Results: Among 1,547 euthyroid patients enrolled (mean age, 56.0 ± 10.5 years), 812 patients (52.5%) had OSA. The FT3/FT4 ratio between OSA and non-OSA patients was not significantly different. During 2.8 (1.4, 3.5) years follow up, the risk of MACCE increased with the decreasing FT3/FT4 tertiles in patients with OSA (tertile3 as reference, tertile2: hazard ratio (HR) 1.26, 95% CI: 0.85-1.86, P = 0.255; tertile1: 1.60, 95% CI 1.11-2.32; P = 0.013). After adjustment for confounders, the lowest FT3/FT4 tertile was still independently associated with an increased risk of MACCE (adjusted HR 1.66, 95% CI 1.11-2.50, P = 0.015).

Conclusion: Lower FT3/FT4 ratio associated with poor prognosis in patients with ACS and OSA.

Keywords: FT3/FT4 ratio; acute coronary syndrome; obstructive sleep apnea; prognosis; thyroid hormones.

pubmed.ncbi.nlm.nih.gov/393...

[BB001]

Thanks helvella. I've only read the abstract and conclusion, but it was enough to find out that this is more research that indicates the importance of T3. I've got diagnosed sleep apnoea and very poor fT3 to fT4 ratio, so I'm glad I'm taking T3.

[helvella Administrator in reply to BB001]

I agree about it being enough! At least as a simple patient it looks like a dire warning.

[arTistapple in reply to helvella]

Yes unfortunately the patients understand this but again the medics ”Hear no evil, See no evil. Speak no evil.”

What a coincidence? I just opened my computer to write a report (for logging only) for my Gp and saw your post about this.

I say for logging only because no medic appears to be listening and I want this stuff on my records.

Thank for finding this, it saves me an enormous amount of effort. I am in pretty short supply of the ability to make effort presently.

[RedApple Administrator]

I wish there was a way to send this (and other relevant research) to all the NHS labs, because so often, it's the lab that refuses to test FT3, even if GP/Endo has requested it.

[helvella Administrator in reply to RedApple]

Well, there is nothing to stop members taking the evidence they have and contacting their labs, NICE, their local decision making bodies, etc.

You do not have to be some sort of expert, trained in medicine, appointed to committees, to express your opinions.

I'd encourage taking time and putting effort in to letters/emails so that they get taken seriously. But it is more important to make representations at all that it is to make them perfect.

[Rapunzel in reply to helvella]

You do not have to be some sort of expert, trained in medicine, appointed to committees, to express your opinions.

Could you possibly alert my GP, Dr Buffoon, to this, helvella? 😘

[Regenallotment Ambassador]

Wow, that’s quite a clear message isn’t it. Such good evidence showing outcomes over the longer term.