Updated
Updated · Medscape · May 18
LT3 Plus LT4 Therapy Raises Psychiatric Risk 43% in 184,266 Hypothyroidism Patients
Updated
Updated · Medscape · May 18

LT3 Plus LT4 Therapy Raises Psychiatric Risk 43% in 184,266 Hypothyroidism Patients

1 articles · Updated · Medscape · May 18
  • A Swedish cohort study found autoimmune hypothyroidism patients starting liothyronine plus levothyroxine faced a 43% higher risk of any psychiatric morbidity than those staying on levothyroxine alone.
  • The signal extended across specific outcomes: affective or anxiety morbidity rose 44%, and psychotic morbidity 46%, after median follow-up of 2.7 years in the combination-therapy group.
  • Among 184,266 adults without prior psychiatric morbidity, 5,346 received LT3 plus LT4 and 178,920 remained on LT4 only; the association held in both sexes and in patients younger than 75.
  • Women on combination therapy had higher psychotic-morbidity risk, and patients younger than 30 showed the strongest increase, with an adjusted hazard ratio of 1.91.
  • The authors said the findings do not prove causation because LT3 may be started in patients already developing poor mental well-being, and the retrospective design left room for confounding and surveillance bias.
Is a common thyroid therapy for fatigue secretly fueling a rise in psychiatric disorders?
Does this thyroid drug cause mental illness, or is it prescribed to patients already developing it?