Lithium-associated clinical hypothyroidism. Prevalence and risk factors

Br J Psychiatry. 1999 Oct;175:336-9. doi: 10.1192/bjp.175.4.336.

Abstract

Background: Rates of, and risk factors for, lithium-associated clinical hypothyroidism are uncertain.

Aims: To determine prevalence of and risk factors for clinical hypothyroidism in patients treated with lithium carbonate.

Method: Retrospective case-note review of 718 patients who had undergone serum lithium estimation during a 15-month period. Patients on thyroxine had a more detailed review.

Results: The prevalence of clinical hypothyroidism during lithium treatment was 10.4%. The main risk factor was female gender (women 14% v. men 4.5%). Women were at highest risk during the first two years of lithium treatment, and women starting lithium aged 40-59 years had the greatest prevalence (> 20%). No equivalent risk factors emerged in men, although, like women, their prevalence of hypothyroidism was substantially higher than community rates.

Conclusions: The high rates of clinical hypothyroidism identified may call for a review of the drug information given to women, particularly to those starting lithium in middle age. Consideration should be given to screening for thyroid antibodies before treatment in high-risk cases. Monitoring of thyroid function should take into account gender, age and stage of lithium treatment.

MeSH terms

  • Adult
  • Age Distribution
  • Aged
  • Female
  • Humans
  • Hypothyroidism / chemically induced*
  • Hypothyroidism / diagnosis
  • Lithium Carbonate / adverse effects*
  • Lithium Carbonate / blood
  • Male
  • Middle Aged
  • Prevalence
  • Retrospective Studies
  • Risk Factors
  • Sex Distribution
  • Survival Analysis

Substances

  • Lithium Carbonate