Background: Alzheimer's disease (AD) is the most common form of dementia and is characterized clinically by a gradual decline in cognitive performance, an increasingly impaired ability to perform activities of daily living, and neuropsychiatric and behavioral disturbances.

Objective: The goal of this study was to assess the effect of rivastigmine on the neuropsychiatric and behavioral disturbances of nursing home residents with moderate to severe probable AD and to evaluate the safety and tolerability of rivastigmine in this population.

Methods: This prospective, 26-week, open-label study was conducted in 13 centers in the United States and involved a total of 29 nursing homes. The effects of rivastigmine 3 to 12 mg/d for 26 weeks were assessed in nursing home residents with moderate to severe probable AD. Efficacy was evaluated using the Neuropsychiatric Inventory-Nursing Home (NPI-NH) scale for neuropsychiatric and behavioral disturbances; the Mini-Mental State Examination and the naming subset of the Alzheimer's Disease Assessment Scale-Cognitive subscale for cognitive performance; and the simplified Clinician's Interview-Based Impression of Change Plus Caregiver Input for global functioning.

Results: A total of 173 patients (141 women, 32 men; mean [SD]age, 82.6 [5.9] years) were enrolled. After 26 weeks of rivastigmine treatment, the mean (SD) change from baseline for all treated patients in the observed cases population was -2.5 (16.4) (n = 100; P = 0.138); it was -0.8 (16.5) (n = 149; P = 0.576) for the last-observation-carried-forward population. Patients with at least 1 neuropsychiatric symptom present at baseline showed a 3.2-point mean improvement in NPI-NH total score (n = 92; P = 0.062), with 49% of these patients demonstrating a clinically meaningful (ie, > or = 30%) reduction from baseline. At 26 weeks, scores for 8 of the 12 neuropsychiatric and behavioral disturbances in patients with the specific symptom present at baseline showed statistically significant improvements from baseline (delusions [n = 32; P = 0.007], hallucinations [n = 15; P < 0.001], agitation [n = 58; P = 0.044], apathy/indifference [n = 37; P < 0.001], irritability/lability [n = 50; P < 0.001], aberrant motor behavior [n = 32; P < 0.001], nighttime disturbances [n = 22; P < 0.001], and appetite/eating changes [n = 28; P = 0.002]) in the observed cases population. Limitations of this study include that it was open label and not restricted to patients with behavioral disturbances at baseline.

Conclusion: In the current study, rivastigmine treatment for 26 weeks in nursing home residents with moderate to severe probable AD was associated with decreased NPI-NH item scores for a wide range of behavioral disturbances in the subgroup of patients with behavioral symptoms at baseline.