Difference between Morning and Evening Thyrotropin Response to Protirelin (TRH) and Prediction of Antidepressant Treatment Outcome in Major Depression (pp. 85-104)
Authors: (Fabrice Duval, Marie-Claude Mokrani, Felix Gonzalez Lopera, Claudia Alexa, Hassen Rabia, Xenia Proudnikova, Alexis Erb, Centre Hospitalier, Rouffach, France)
Abstract: Background: Early predictors of response are needed to improve effectiveness of antidepressant treatment. This study sought to determine whether the chronobiological evaluation of thyroid function at baseline and after 2 weeks of treatment could predict antidepressant response in hospitalized patients.
Methods: The serum levels of thyroid hormones and thyrotropin (TSH) were evaluated before and after 08.00 h and 23.00 h protirelin (TRH) tests, on the same day, in 30 drug-free DSM-IV euthyroid major depressed inpatients and 30 hospitalized controls. After 2 weeks of antidepressant treatment (extended-release venlafaxine, n=15; tianeptine, n=15) the same TRH tests were repeated in all inpatients. Antidepressant response was evaluated after 6 weeks of treatment.
Results: At baseline, TSH values (pre- and post-TRH [ΔTSH]) at 23.00 h, and ΔΔTSH (difference between 23.00 h-ΔTSH and 08.00 h-ΔTSH) were significantly lower in patients compared to controls. Pretreatment thyroid function tests were not associated with clinical outcome. After 2 weeks of treatment, patients with reduced ΔΔTSH values showed poor clinical outcome, while those with normal ΔΔTSH values showed full response at week 6 (p<0.0006). A logistic regression revealed that ΔΔTSH values at week 2 predicted endpoint clinical response (odds ratio, 3.30; 95% confidence interval, 1.35 to 8.08; p = 0.009).
Limitations: Findings are limited by the small sample size, and are not transposable to outpatients.
Conclusions: Although further research is necessary to establish firm conclusions, our results suggest that the ΔΔTSH test performed early during antidepressant treatment could be used to predict eventual outcome and guide treatment decision.