Thyroxine plus triiodothyronine and thyroxine
alone have similar efficacy in patients with hypothyroidism
(March 2004)
The background of the study. Thyroxine (T4) therapy
may not restore normal health and well being in patients with hypothyroidism.
This study was done to determine if replacing some T4 with triiodothyronine
(T3) resulted in improvement in symptoms in both unsatisfied and
satisfied patients with hypothyroidism.
How the study was done. The study subjects were
110 patients (101 women) with hypothyroidism who had been taking
at least 100 µg of T4 daily (mean dose, 136 µg) for
at least two months. At base line, 45 percent felt well and were
satisfied with their treatment and 55 percent were not satisfied,
because of persistent symptoms such as decreased well-being, fatigue,
and weight gain.
The patients were randomly assigned to receive their usual T4 dose
or a 50 µg lower dose of T4 plus 10 µg of T3 (in identical
capsules) once daily for 10 weeks. The patients then took their
usual T4 dose for four weeks, after which they took the opposite
treatment for 10 weeks. At base line and at the end of each treatment
period, the patients were examined and completed questionnaires,
including the Short Form 36 (a general health questionnaire), the
General Health Questionnaire (GHQ), which measures psychological
dysfunction, the Thyroid Symptom Questionnaire (TSQ), and a satisfaction
scale. Cognitive function also was tested.
The results of the study. There were no changes
in weight or blood pressure at any time. The mean serum thyrotropin
concentration was slightly higher and the mean serum free T4 concentration
was lower after T4-plus-T3 treatment. There were no differences
in the scores for the Short Form 36, the GHQ, the TSQ, and the satisfaction
scale, or the results of the cognitive function tests at the end
of the two treatment periods.
The conclusions of the study. The combination
of T4 and T3 is no more effective than T4 alone in ameliorating
symptoms and improving quality of life in patients with hypothyroidism.
The original article. Walsh JP, Shiels L, Lim
EM, Bhagat CI, Ward LC, Stuckey BG, Dhaliwal SS, Chew GT, Bhagat
MC, Cussons AJ. Combined thyroxine/liothyronine treatment does not
improve well being, quality of life, or cognitive function compared
to thyroxine alone: a randomized controlled trial in patients with
primary hypothyroidism. J Clin Endocrinol Metab 2003;88:4543-50.
|
