Abstract
Context Patients previously treated with desiccated thyroid extract (DTE), when being switched to levothyroxine (L-T₄), occasionally did not feel as well despite adequate dosing based on serum TSH levels.
Objective Our objective was to investigate the effectiveness of DTE compared with L-T₄ in hypothyroid patients.
DESIGN AND
Setting We conducted a randomized, double-blind, crossover study at a tertiary care center.
Patients Patients (n = 70, age 18-65 years) diagnosed with primary hypothyroidism on a stable dose of L-T₄ for 6 months were included in the study.
Intervention Patients were randomized to either DTE or L-T₄ for 16 weeks and then crossed over for the same duration.
OUTCOME
Measures Biochemical and neurocognitive tests at baseline and at the end of each treatment period were evaluated.
Results There were no differences in symptoms and neurocognitive measurements between the 2 therapies. Patients lost 3 lb on DTE treatment (172.9 ± 36.4 lb vs 175.7 ± 37.7 lb, P < .001). At the end of the study, 34 patients (48.6%) preferred DTE, 13 (18.6%) preferred L-T₄, and 23 (32.9%) had no preference. In the subgroup analyses, those patients who preferred DTE lost 4 lb during the DTE treatment, and their subjective symptoms were significantly better while taking DTE as measured by the general health questionnaire-12 and thyroid symptom questionnaire (P < .001 for both). Five variables were predictors of preference for DTE.
Conclusion DTE therapy did not result in a significant improvement in quality of life; however, DTE caused modest weight loss and nearly half (48.6%) of the study patients expressed preference for DTE over L-T₄. DTE therapy may be relevant for some hypothyroid patients.
desiccated thyroid extract versus levothyroxine randomized crossover, natural thyroid hormone replacement hypothyroidism treatment, Armour thyroid compared to synthetic levothyroxine, patient preference desiccated thyroid extract weight loss, hypothyroidism treatment randomized double blind crossover study, desiccated thyroid extract neurocognitive outcomes quality of life, T3 T4 combination therapy hypothyroidism, levothyroxine inadequate symptom control thyroid replacement, thyroid symptom questionnaire desiccated thyroid, natural versus synthetic thyroid hormone clinical trial
Keywords
Adult, Aged, Animals, Cognition/drug Effects, Cognition Disorders/chemically Induced/etiology/prevention & Control, Cross-Over Studies, Dietary Supplements/adverse Effects, Double-Blind Method, Female, Hormone Replacement Therapy/adverse Effects, Humans, Hypothyroidism/blood/diet Therapy/drug Therapy/physiopathology, Male, Middle Aged, Patient Preference, Quality of Life, Receptors, Thyroid Hormone/agonists, Severity of Illness Index, Thyroid Gland/chemistry, Thyroid Hormones/blood, Thyroxine/adverse Effects/therapeutic Use, Tissue Extracts/adverse Effects/therapeutic Use, Weight Loss/drug Effects, Young Adult, Receptors, Thyroid Hormone, Thyroid Hormones, Tissue Extracts, Thyroxine