Factors associated with increased caregivers' burden in several cognitive stages of Alzheimer's disease.

AIM: To investigate factors associated with caregiver burden (CB) in persons caring for older adults with various cognitive stages of Alzheimer's disease (AD).
METHODS: Participants were 1127 outpatients and their caregivers. Participants comprised 120 older adults with normal cognition (NC), 126 with amnestic mild cognitive impairment (aMCI) and 881 with AD. AD patients were subclassified into four groups by Mini-Mental State Examination (MMSE) score: AD29-24 (n = 117), AD23-18 (n = 423), AD17-12 (n = 254) and AD11-0 (n = 87). Participants and their caregivers underwent comprehensive geriatric assessment batteries including Zarit Burden Interview (ZBI) Barthel Index, Lawton Index, Dementia Behavior Disturbance Scale (DBD) to evaluate CB, Instrumental and Basic Activity of Daily Living (IADL/BADL), and Behavioral and Psychological Symptoms of Dementia (BPSD). The comorbidity of geriatric syndrome and the living situation of the patient/caregiver were also assessed.
RESULTS: ZBI score was higher in patients with lower MMSE score. Multivariate regression analysis identified that DBD was consistently associated with CB in all patients; symptoms related to memory deficit were related to CB in aMCI; differential IADL, such as inability to use a telephone, use transportation, manage finances, shop, cook and take responsibility for own medication, were related to CB in AD29-24, AD23-18 and AD17-12, and geriatric syndrome including falls and motor disturbance, sleep problems, urinary incontinence, and fatigue was related to CB in AD23-18 and AD17-12.
CONCLUSIONS: Multiple factors including BPSD, impaired life function and geriatric syndrome were cognitive stage-dependently associated with CB. Preventive treatment of BPSD and comorbidity, and effective assistance for IADL deficits could contribute to alleviation of CB.