OBJECTIVES: To examine the patterns and predictors of off-label antipsychotic use among older adults with dementia in the ambulatory care settings in US.

METHODS: This was a retrospective, cross-sectional study using pooled data from the National Ambulatory Medical Care Survey (NAMCS) (2005-2015). The study sample consisted of ambulatory visits by older adults (age ≥ 65 years) with dementia who were prescribed off-label antipsychotic(s). Dementia was identified by using ICD-9-CM codes of 290.xx, 294.xx, or 331.xx or by examining use of cholinesterase inhibitors or memantine. Antipsychotics are approved for treating individuals with schizophrenia (ICD-9-CM: 2950x–2959x), bipolar disorder (ICD-9-CM: 2960x, 2961x, 2964x–2969x), Tourette syndrome (ICD-9-CM: 307.23), or Huntington’s disease (ICD-9-CM: 333.4). Ambulatory visits where older adults with dementia had co-occurring schizophrenia, bipolar disorder, Tourette syndrome or Huntington’s disease were excluded from the final study sample to examine the off-label antipsychotic use. Predictors of off-label antipsychotic use were determined using multivariable logistic regression adjusting for individual-level factors. All analyses were adjusted for the complex survey design of NAMCS to obtain nationally representative estimates.

RESULTS: Over the 11-year study period, there over 74 million visits by older adults with dementia without conditions approved for treatment with an antipsychotic, among whom 6.2 million (8.37%) visits received an off-label antipsychotic prescription. Factors that were significantly associated with off-label antipsychotic use were age, gender, race/ethnicity, physician specialty, region, number of medications recorded at the sampled visit, and number of past visits. For example, non-Hispanic Whites were 75% (Odds Ratio: 1.75, 95%CI: 1.06-2.90, p=0.03) more likely to receive off-label antipsychotics compared to other race/ethnic groups.

CONCLUSIONS: Over 8% of older adults with dementia received off-label antipsychotic in this nationally-representative ambulatory care sample in US and several factors associated with off-label use were identified. Appropriate interventions are warranted to minimize off-label antipsychotic use in this vulnerable population.