Endocrine Abstracts

Methodology: Between Jan’20 to Jan’21, 364 patients on thyroid replacement therapy were included in the study and analysed retrospectively. They were divided in 2 groups. T4 group (189 on levothyroxine therapy {T4} therapy) & T3 group (175 on levothyroxine/liothyronine combination therapy {T3/T4}. Hypothyroidism was defined as TSH >4.2 mIU/ml on > 2 occasions > 2 weeks apart irrespective of their thyroid antibody (anti-TPO Ab) status or TSH > 4.2 if symptomatic or positive Anti-TPO Ab. Patients were evaluated every 2-3 months for 6 months for CV markers [body mass index-kg/m² (BMI), systolic (S) BP, diastolic (D) BP {mm in Hg}, Lipid profile mg/dl (TC, LDL, TG, HDL), Hs-CRP {mg/l}]. Baseline characteristics were analysed using descriptive statistics. Data was analysed using SPSS 26 and represented as mean ± standard error & independent sample t-test was used. P value <0.05 was considered significant (S).

Results: Baseline characters were well matched in both groups except, DBP (mean±SD) (T4 77.72±9.601 Vs T3/T4 81.69±10.87, P-0.00) & LDL (T4 105.121±33.689 Vs T3/T4 114.687±33.9196, P-0.02). T4 group (baseline to 6 months): there was a S reduction in SBP (3.323±0.941, P-0.01), TSH (4.4522±0.7602, P-0.00), TC (14.04274±3.24371, P-0.00), LDL (11.42795±3.03657, P-0.00), TG (16.15090±3.73617, P-0.00). T3/T4 group (baseline to 6 mths): there was S reduction in BMI (0.5160±0.1213, P-0.00), TSH (6.1134406±1.4832301, P-0.00), TC (12.75764±2.80435, P-0.00), LDL (11.63343±2.72702, P-0.00), TG (8.45775±4.38677, P-0.05). Difference between T4 & T3/T4 at 6 mths: There was no difference in hs-CRP mg/l {T4 0.2947±0.3071 vs T3/T4 0.9844±0.3602, P-0.677}, BMI kg/m² {T4 0.2361±0.1892 vs T3/T4 0.5160± 0.1213, P-0.222}, Lipid parameters, SBP & DBP between both groups.

Conclusion: Both T3/T4 combination therapy & T4 are effective in improving lipid parameters. Both T4 & T3/T4 do not impact either hs-CRP or BP.