Effects of Long-Term Combination LT4 and LT3 Therapy for Improving Hypothyroidism and Overall Quality of Life

[helvella]

No introduction needed…

South Med J. 2018 Jun;111(6):363-369. doi: 10.14423/SMJ.0000000000000823.

Effects of Long-Term Combination LT4 and LT3 Therapy for Improving Hypothyroidism and Overall Quality of Life.

Tariq A1, Wert Y1, Cheriyath P1, Joshi R1.

Author information

1 From the Departments of Internal Medicine, Research and Biostatistical Analysis, and Endocrinology, UPMC Pinnacle Health, Harrisburg, Pennsylvania.

Abstract

OBJECTIVES:

Hypothyroidism results in decreased mood and neurocognition, weight gain, fatigue, and many other undesirable symptoms. The American Association of Clinical Endocrinologists, the American Thyroid Association (ATA), and The Endocrine Society recommend levothyroxine (LT4) monotherapy as the treatment for hypothyroidism; however, after years of monotherapy, some patients continue to experience impaired quality of life. Combination LT4 and synthetic liothyronine (LT3) therapy or the use of desiccated thyroid extract (DTE), has not been suggested for this indication based on short-duration studies with no significant benefits. Our first observational study examined the role of combination therapy for 6 years in improving quality of life in a subset of a hypothyroid population without adverse effects and cardiac mortality.

METHODS:

An observational retrospective study examining patients prescribed thyroid replacements with serum triiodothyronine (FT3), LT4 with LT3 (synthetic therapy) or DTE (natural therapy), compared with LT4 alone in the United States from 2010 to 2016. Thyroid-stimulating hormone (TSH), serum thyroxine (FT4), and FT3 levels were documented for each patient in addition to any admissions of myxedema coma, thyrotoxicosis, or cardiovascular complications, such as arrhythmias, atrial fibrillation, and mortality. At the conclusion of the study, a cross-sectional interview assessed quality of life for each combination therapy through the Medical Outcomes Study Short Form-20 questionnaire.

RESULTS:

Compared with patients taking only LT4, 89.47% using synthetic therapy had therapeutic TSH (P < 0.05). Similarly, 96.49% using natural therapy had therapeutic TSH (P < 0.05). Less than 5% of patients had supratherapeutic FT3. None of the patients who had abnormally low TSH or elevated FT3 or FT4 levels had hospitalizations for arrhythmias or thyrotoxicosis. On the Medical Outcomes Study Short Form-20 questionnaire, >92% answered feeling "excellent, very good, or good" when questioned about their health while undergoing thyroid replacement compared with levothyroxine alone.

CONCLUSIONS:

This is the only retrospective study reported to use long-term (mean 27 months) thyroid replacements with combination therapy and to compare between the two forms of therapy: synthetic and natural. For patients undergoing either therapy, we did not identify additional risks of atrial fibrillation, cardiovascular disease, or mortality in patients of all ages with hypothyroidism.

PMID: 29863229

DOI: 10.14423/SMJ.0000000000000823

ncbi.nlm.nih.gov/pubmed/298...

[ 05/06/2018 22:00 edited to add:

PR4NOW has posted a link to the abstract - on which you can click to get the full paper and download it - repeated here:

sma.org/southern-medical-jo... ]

[Musicmonkey]

Simply love this 😊 Thanks for posting helvella

[Murphysmum]

So, despite having a science background, I’m quite new to this forum and all the expertise imparted but even so - I look at this and think “no sh*t”!! 😂

[helvella Administrator in reply to Murphysmum]

What sticks in our throats is the absolute assertions so many have received about the utter perfection of levothyroxine monotherapy and the extreme damage that will undoubtedly be caused by taking desiccated thyroid and/or liothyronine. But those assertions simply cannot have been based on research otherwise this paper couldn't and wouldn't say:

This is the only retrospective study reported to use long-term (mean 27 months) thyroid replacements with combination therapy and to compare between the two forms of therapy: synthetic and natural.

[Murphysmum in reply to helvella]

Indeed. I looked into this a bit many years ago when I was diagnosed but as everything seems to work quite well I never gave it any more thought. Different now though, seriously thinking about it

[PR4NOW]

Interesting find, thanks. The link to the full article which can be saved. You have to click on 'article' next to 'abstract' in the heading bar. PR

sma.org/southern-medical-jo...

[helvella Administrator in reply to PR4NOW]

Thank you, PR4NOW!

Something didn't work when I was preparing my post and so I thought it was not (yet?) available.

[Marz in reply to helvella]

Maybe the link should be Pinned so members have easy access when needed. Almost daily it seems - now the latest fad seems to be reducing Levo ....

Thank you for posting.

[SilverAvocado]

Really useful paper, thanks for sharing!

[diogenes Remembering]

This paper should be communicated to the NICE team that is re-examining the proposed guidelines for thyroid treatment in th UK. Perhaps this should be done through TUK as a formal offering through appropriate channels. Its conclusions exactly confirm our own study findings in physiology of the thyroid, extended to the practical value (and safety) of properly controlled combination trials. Note that the combination groups were separated in the analyses - a factor we have always said was destroyed in randomised trials owing to "swamping" of the minority by the indifferent majority.

[helvella Administrator in reply to diogenes]

LouiseRoberts lynmynott

Could you pick up diogenes’ comments, please?