Treatments for bipolar disorder: can number needed to treat/harm help inform clinical decisions?

Acta Psychiatr Scand. 2011 Mar;123(3):175-89. doi: 10.1111/j.1600-0447.2010.01645.x. Epub 2010 Dec 7.

Abstract

Objective: To compare bipolar treatment interventions, using number needed to treat (NNT) and number needed to harm (NNH).

Method: Results of randomized controlled clinical trials were used to assess efficacy (NNT for response and relapse/recurrence prevention vs. placebo) and tolerability (e.g. NNH for weight gain and sedation vs. placebo).

Results: United States Food and Drug Administration-approved bipolar disorder pharmacotherapies all have single-digit NNTs (i.e. > 10% advantage over placebo), but NNHs for adverse effects that vary widely. Some highly efficacious agents are as likely to yield adverse effects as therapeutic benefit, but may be interventions of choice in more acute severe illness. In contrast, some less efficacious agents with better tolerability may be interventions of choice in more chronic mild-moderate illness.

Conclusion: Clinical trials can help inform clinical decision making by quantifying the likelihood of benefit vs. harm. Integrating such data with individual patient circumstances, values, and preferences can help optimize treatment choices.

MeSH terms

  • Acute Disease
  • Antimanic Agents / adverse effects
  • Antimanic Agents / therapeutic use
  • Antipsychotic Agents / adverse effects
  • Antipsychotic Agents / therapeutic use
  • Bipolar Disorder / drug therapy*
  • Confidence Intervals
  • Humans
  • Randomized Controlled Trials as Topic / methods
  • Randomized Controlled Trials as Topic / standards
  • Sample Size
  • Secondary Prevention
  • Treatment Outcome

Substances

  • Antimanic Agents
  • Antipsychotic Agents