Aims: We performed an observational and retrospective study involving patients with hypothyroidism and gastric diseases in treatment with liquid levothyroxine (L-LT4) or tablet L-T4 (T-LT4). We assessed and compared TSH stability in these patients.
Methods: Eighty-four patients were in treatment with L-LT4, and 120 patients with T-LT4. The patients were affected by many types of gastric disease. In the T-LT4 group, 74 patients with chronic gastritis (CG), 4 with gastrectomy for gastric cancer (GTx) and 42 with gastro-plastics (GP), whereas in L-LT4 group, 60 with CG, 3 with GTx and 21 with GP (p>0.05). In the T-LT4 group 66% of the patients were chronically treated with PPI, against 51% in the L-LT4 group (p>0.05). The frequency of Helicobacter Pylori infection was 17% in both T-LT4 and L-LT4 groups. Gender distribution, mean age and body weight were comparable in the two groups (p>0.05). In the T-LT4 group the L-T4 mean dosage at the basal evaluation was 1.22+/-0.27 μg/kg/die, whereas in the L-LT4 group was 1.36+/-0.22 μg/kg/die (p>0.05).
Results: The basal evaluation reported a prevalence of patients with a TSH > 3.5 μIU/mL in the T-LT4 group of 36%, whereas in the L-LT4 group was of 46% (p<0.05). The patients were re-evaluated in an interval of 5-9 months, for 4 times, over period from 23 to 31 months.
The prevalence of patients with a TSH>3.5 μIU/mL in the T-LT4, or in the L-LT4 groups were respectively: a) at first revaluation 13%, 13%; b) at second revaluation 26%, 13%; d) at third revaluation 19%, 9%; d) at fourth revaluation 18% and 5% (p<0.05 for all comparisons). Mean FT4 and FT3 circulating levels were not significantly different in the two groups.
Conclusion: We demonstrated that liquid L-T4 ensures more stable long-term TSH control than L-T4 tablets in hypothyroid patients with gastric disorders.