Abstract
BACKGROUND: Until recently, treatment of hypothyroidism has been accomplished using monotherapy of synthetic L-thyroxine (L-T4) sodium tablets that should be taken 30-60 minutes before breakfast. Nowadays, a liquid preparation of levothyroxine is available and can effectively replace tablets without the need of waiting before having breakfast. Evidence of Quality of life (QoL) improvement when shifting from the former to the latter preparation, however, is still lacking. OBJECTIVE: The study aimed to assess changes in QoL of hypothyroid patients dissatisfied with their therapy with L-T4 sodium tablets who were switched from tablets taken 30-60 minutes before breakfast to liquid L-T4 at breakfast. METHODS: A total of 418 consecutive hypothyroid subjects treated by means of L-T4 tablets were asked about their satisfaction/dissatisfaction in order to take the medication 30-60 minutes before having breakfast. Overall, 110 patients (26.3%) complained of the timing of their L-T4 therapy (30-60 minutes before breakfast). A dedicated QoL questionnaire (ThyTSQ), taking just a few minutes to be filled in was then administered to these dissatisfied patients. They were therefore switched to L-T4 to be taken at breakfast. Aiming to avoid TSH elevation due to L-T4 tablets malabsorption caused by meal interference and gastric pH changes, patients were invited to take L-T4 liquid form, as this is claimed to be scarcely affected by the non-fasting state. The questionnaire (ThyTSQ) was administered again at the control visit 3 months later. TSH, FT4, FT3 serum concentrations and metabolic parameters were also recorded. RESULTS: An improved QoL, mainly due to an easier adherence to treatment, was reported by 66.6% of 102 patients who completed the study after shifting from taking medication 30-60 minutes before breakfast to at breakfast ingestion (P<0.01). An overall 10.7% of patients found the liquid formulation distasteful. Mean values of TSH, FT4, FT3, and of metabolic parameters did not significantly change but in eight patients (7.7%) who showed a TSH increase > 2mIU/L. CONCLUSION: In hypothyroid subjects dissatisfied with L-T4 tablets ingested 30-60 minutes before breakfast, the shift to the same dose of L-T4 in liquid form taken at breakfast improved QoL in the majority of patients, without affecting thyroid function.