Lithium-associated hypothyroidism and potential for reversibility after lithium discontinuation: Findings from the LiSIE retrospective cohort study

Abstract

Background: The association between lithium and thyroid dysfunction has long been known. However, it remains unknown if lithium-associated hypothyroidism is reversible once lithium treatment has been stopped. Aims: To determine whether lithium-associated hypothyroidism was reversible in patients who subsequently discontinued lithium. Methods: A retrospective cohort study in the Swedish region of Norrbotten into the effects and side- effects of lithium treatment and other drugs for relapse prevention (Lithium – Study into Effects and Side Effects). For this particular study, we reviewed medical records between 1997 and 2015 of patients with lithium-associated hypothyroidism who had discontinued lithium. Results: Of 1340 patients screened, 90 were included. Of these, 27% had overt hypothyroidism at the start of thyroid replacement therapy. The mean delay from starting lithium to starting thyroid replacement therapy was 2.3 years (SD 4.7). In total, 50% of patients received thyroid replacement therapy within 10 months of starting lithium. Of 85 patients available for follow-up, 41% stopped thyroid replacement therapy after lithium discontinuation. Only six patients reinstated thyroid replacement therapy subsequently. Of these, only one had overt hypothyroidism. Conclusions: Lithium-associated hypothyroidism seems reversible in most patients once lithium has been discontinued. In such cases, thyroid replacement therapy discontinuation could be attempted much more often than currently done. Based on the limited evidence of our study, we can expect hypothyroidism to recur early after thyroid replacement therapy discontinuation, if at all.

Patterns of Thyroid Hormone Prescription in Patients with Bipolar or Schizoaffective Disorder: Findings from the LiSIE Retrospective Cohort Study

“…LiSIE invited all individuals in the Swedish regions of Västerbotten and Norrbotten ≥18 years of age, who had either received, according to the Tenth Revision of the International Classification of Diseases (ICD-10), a diagnosis of BD (ICD F31) or SZD (ICD F25) between 1997 and 2011, or who had used lithium as MS between 1997 and 2011 [ 29 ]. We excluded patients who, after manual validation from the medical records, more likely had a diagnosis of schizophrenia than BD or SZD [ 30 ].…”

“…For the current study, we excluded patients who had received (a) THRT after goitre surgery, (b) an explicit diagnosis of hyperthyroidism/thyrotoxicosis before THRT initiation, or (c) THRT without recording of TFT or information regarding the reasons for THRT initiation [ 29 ]. We also excluded patients who, at THRT initiation, were less than 18 years old, ( Figure 1 ).…”

“…We recorded the age at THRT initiation. Based on a previous study on the long-term effects of lithium on thyroid and other organ functions, we stratified age into two categories, <60 or ≥60 years [ 29 ].…”

“…The indication for THRT is rarely revisited. This may hold true, even if potentially offending agents such as lithium are withdrawn [ 29 ].…”

Clinical practice guidelines for acute and chronic thyroiditis (excluding autoimmune thyroiditis)

“…Тем не менее препараты лития являются основным компонентом в комплексном лечении биполярного расстройства. Отказ от нее из-за развившейся тиреоидной патологии, которая удовлетворительно компенсируется медикаментозно и нередко имеет транзиторный характер, не обоснован [ 149 ][ 150 ].…”