Trends in prescriptions of lithium and other medications for patients with bipolar disorder in office-based practices in the United States: 1996-2015

J Affect Disord. 2020 Nov 1:276:883-889. doi: 10.1016/j.jad.2020.07.063. Epub 2020 Jul 21.

Abstract

Background: Studies have shown that rates of lithium use for bipolar disorder in the United States declined through the 1990s as other mood stabilizing anticonvulsants and second-generation antipsychotics (SGAs) became more popular. We examined trends of medications for bipolar disorder from 1996 to 2015.

Methods: Twenty years of data from the National Ambulatory Medical Care Survey (NAMCS) were used. Weighted percentages of reported use of lithium, anticonvulsants, SGAs and antidepressants were calculated over two-year intervals. Logistic regression was used to examine factors related to polytherapy.

Results: Reported use of lithium declined from 38.1% (95%CI: 29.8% - 46.3%) in 1996-97 to 14.3% (95%CI: 10.6% - 18.1%) in 2006-07 and has remained stable since. During this time, reports of SGAs more than doubled. SGAs and/or anticonvulsants were reported in 75.4% (95%CI: 69.5% - 81.3%) of visits with bipolar diagnoses in 2014-15. Polytherapy increased by approximately 3% every two years and in 2014-15 occurred in over 30% of visits. Antidepressants were reported in 40-50% of visits, but their reported use without other mood stabilizers decreased from 18.2% (95%CI: 11.7% - 24.8%) in 1998-99 to 7.5% (95%CI: 4.2% - 10.9%) in 2014-15.

Limitations: The sample had limited power to study the effect of individual medications or the potential for differing effects in certain sub-groups of patients.

Conclusions: This study further documents the declining use of lithium for bipolar disorder, and corresponding increase in use of anticonvulsants and SGAs, despite the fact that lithium is typically recommended as a first line therapy for bipolar disorder.

Keywords: Anticonvulsants; Antidepressants; Antipsychotic agents; Drug therapy, combination; Lithium.

MeSH terms

  • Anticonvulsants / therapeutic use
  • Antimanic Agents / therapeutic use
  • Antipsychotic Agents* / therapeutic use
  • Bipolar Disorder* / drug therapy
  • Bipolar Disorder* / epidemiology
  • Humans
  • Lithium / therapeutic use
  • Prescriptions
  • United States

Substances

  • Anticonvulsants
  • Antimanic Agents
  • Antipsychotic Agents
  • Lithium