Neuropsychiatric symptoms in Alzheimer's disease: associations with caregiver burden and treatment outcomes

Background: Caregivers play a major role in providing care for patients with Alzheimer's disease (AD) and are themselves at higher risk of health comorbidities. Aim: To address the impact of neuropsychiatric symptoms of patients in different stages of AD on their caregivers' burden. Design: This prospective study enrolled 260 AD patients with clinical dementia rating (CDR) of 0.5, 1 and 2 at a tertiary medical center. Methods: All patients were tested using the mini-mental state examination (MMSE), the cognitive abilities screening instrument (CASI), the neuropsychiatric inventory (NPI) and the CDR scale. Data regarding therapeutic outcomes of anti-Alzheimer's drugs were also collected. Caregivers were tested using NPI. Results: The mean follow-up interval was 25.0612.2 months, and two patients died during follow-up. NPI-burden was positively correlated with NPI-sum (r = 0.822, P < 0.001) but negatively correlated with years of education (r = -0.140, P = 0.024), CASI score (r = -0.259, P < 0.001) and MMSE score (r = -0.262, P < 0.001). Multiple linear regression analysis showed that only NPI-sum was independently associated with mean NPI-burden. Both higher mean CASI and MMSE scores had better therapeutic outcome of anti-Alzheimer's drugs (P = 0.001 and P = 0.005, respectively). Conclusions: The severity of neuropsychiatric symptoms in patients with AD was positively associated with caregiver's stress, and patients with better cognitive functions, under treatment with anti-Alzheimer's drugs, had better therapeutic outcomes. To reduce the impact of neuropsychiatric symptoms, it is crucial to detect dementia in its early phases and provide early intervention with anti-Alzheimer's drugs, which might help decrease the caregiver burden, thereby improving their quality of life.