Unexplained variation across US nursing homes in antipsychotic prescribing rates.

BACKGROUND Serious safety concerns related to the use of antipsychotics have not decreased the prescribing of these agents to nursing home (NH) residents. We assessed the extent to which resident clinical characteristics and institutional prescribing practice were associated with antipsychotic prescribing. METHODS Antipsychotic prescribing was assessed for a nationwide, cross-sectional population of 16 586 newly admitted NH residents in 2006. We computed facility-level antipsychotic rates based on the previous year's (2005) prescribing patterns. Poisson regressions with generalized estimating equations were used to identify the likelihood of resident-level antipsychotic medication use in 2006, given 2005 facility-level prescribing pattern and NH resident indication for antipsychotic therapy (psychosis, dementia, and behavioral disturbance). RESULTS More than 29% (n = 4818) of study residents received at least 1 antipsychotic medication in 2006. Of the antipsychotic medication users, 32% (n = 1545) had no identified clinical indication for this therapy. Residents entering NHs with the highest facility-level antipsychotic rates were 1.37 times more likely to receive antipsychotics relative to those entering the lowest prescribing rate NHs, after adjusting for potential clinical indications (risk ratio [RR], 1.37; 95% confidence interval [CI], 1.24-1.51). The elevated risk associated with facility-level prescribing rates was apparent for only NH residents with dementia but no psychosis (RR, 1.40; 95% CI, 1.23-1.59) and residents without dementia or psychosis (RR, 1.54; 95% CI, 1.24-1.91). CONCLUSIONS The NH antipsychotic prescribing rate was independently associated with the use of antipsychotics in NH residents. Future research is needed to determine why such a prescribing culture exists and whether it could result in adverse health consequences.