New insights: dose-response relationship between psychotropic drugs and falls: a study in nursing home residents with dementia.

The contribution of specific psychotropic drugs to fall risk in patients with dementia has not been quantified precisely until now. The authors evaluated the dose-response relationship between psychotropic drugs and falls in nursing home residents with dementia. Daily drug use and daily falls were recorded in 248 nursing home residents with dementia from January 1, 2006, to January 1, 2008. For each day of the study period, data on drug use were abstracted from the prescription database, and falls were retrieved from a standardized incident report system, resulting in a data set of 85 074 person-days. The authors found significant dose-response relationships for the use of antipsychotics (hazard ratio [HR], 2.78; 95% confidence interval [CI], 1.49-5.17), anxiolytics (1.60; 1.20-2.14), hypnotics and sedatives (2.58; 1.42-4.68), and antidepressants (2.84; 1.93-4.16). Fall risk increased significantly with 28% at 0.25 of the defined daily dose (DDD) of an antipsychotic or antidepressant, with 8% at 0.2 of the DDD of an anxiolytic, and with 56% at 0.5 of the DDD of a hypnotic or sedative; it increased further with dose increments and with combinations of psychotropics. Even at low dosages, psychotropic drugs are associated with increased fall risk in nursing home residents with dementia.