Low-Dose Atypical Antipsychotic Risperidone Improves the 5-Year Outcome in Alzheimer's Disease Patients with Sleep Disturbances

Sleep disturbances (SD) accelerate the progression of Alzheimer's disease (AD) and increase the stress of caregivers. However, the long-term outcome of disturbed nocturnal sleep/wake patterns in AD and on increased stress of spousal caregivers is unclear. This study assessed the 5-year effect of nocturnal SD on the long-term outcome in AD patients. A total of 156 donepezil-treated mild-moderate AD patients (93 AD + SD and 63 AD - SD as a control group) were recruited. The AD + SD patients were formed into 4 subgroups according to the preferences of spousal caregivers for treatment with atypical antipsychotics (0.5-1 mg risperidone, n = 22), non-benzodiazepine hypnotic (5-10 mg zolpidem tartrate, n = 33), melatonin (2.55 mg, n = 9), or no-drug treatment (n = 29). SD were evaluated by polysomnography, sleep scale, and cognitive scale examinations. Moreover, all spousal caregivers of AD patients were assessed using a series of scales, including sleep, anxiety, mood, and treatment attitude scales. Our data showed that nocturnal sleep/wake disturbances were significantly associated with lower 5-year outcomes for AD patients, earlier nursing home placement, and more negative emotions of spousal caregivers. Treatment with low-dose atypical antipsychotic risperidone improved the 5-year outcome in AD + SD patients. In conclusion, low-dose atypical antipsychotic risperidone improves the 5-year outcome in AD patients with SD. Moreover, improvement of nocturnal sleep problems in AD patients will also bring better emotional stability for AD caregivers.