Endocrine Abstracts

Aim: To asses the role of Liothyronine (T3)+Levothyroxine combination (T4) therapy in 70 overweight/obese patients with Thyrotropin Stimulating Hormone (TSH mIU/ml) between 2.5-5 who were unable to lose weight.

Methods: Between Jan’ 20 - Jan’ 21, 70 overweight/obese patients with TSH 2.5 -5 performed on ± 2 occasions ± 4 weeks apart were retrospectively analyzed. 24% {17/70} had TSH 2.5-2.99, 37% {26/70} had TSH 3-3.99 & 39% {27/70} had TSH 4.0-4.99. Twenty% {14/70} were anti-topoisomerase antibody (TPOAb) +ve of which 5.71% had TSH 2.5-2.99, 5.71% had TSH 3-3.99 & 8.57% had TSH 4-4.99. Eighty% {56/70} were TPOAb -ve. They were referred by a nutritionist for inability to lose weight despite being on > 3 months weight loosing regimen (<1000Kcal/day). Protocol: Patients were initiated T3 25 mg/day along with varying doses of T4 to help optimize the TSH (lower limit of normal reference range) & followed 2-3 mths for 6 mths for clinical/cardiac parameters: weight (W-kg), body mass index (BMI-kg/m²), systolic BP (SBP-mm of Hg), diastolic BP (DBP-mm of Hg), TSH, Lipid profile mg/dl (TC, LDL-C, TG, HDL) & Hs-CRP mg/l. Continuous variables were analyzed using paired & unpaired t-test expressed as mean ± standard error. For interaction between drug class, ANOVA was used & p value <0.05 was considered significant (S).

Results: Baseline (B) characteristics: Avg. age 39.89±11.215yrs, Female/Male ratio 62/8 (88.6%/11.4%), avg. BMI 29.0409±7.29339, SBP 119.79±15.752, DBP 80.37±12.040, TSH 3.824707±0.9896442, TC 184.3203±39.52749, LCL-C 116.6784±38.96588, hs-CRP 4.5114±5.59016. Differences between B to 6 months: S reduction in W (1.7500±0.4796, p-0.001), BMI (0.80243±0.21892, p-0.000), TSH (2.2562429±0.2213319, p-0.000), TC (17.85610±4.93128, p-0.001), LDL-C (17.09672±5.06238, p-0.001) were seen, with no changes in SBP, DBP, TG, HDL, hs-CRP.

Conclusion: T3/T4 combination therapy is effective in initiating weight loss and improving lipid profile in patients with TSH between 2.5-5, without any adverse effect on SBP/DBP. Symptomatic patients with TSH between 2.5-5 can be initiated T3/T4 combination therapy as it leads to both weight loss and improvements in TC & LDL which might have beneficial long term cardiovascular effects.