Risk factors and characteristics of the recurrence of behavioral and psychological symptoms of Alzheimer's disease

BackgroundThere is limited data on the risk factors and characteristics of the recurrence of behavioral and psychological symptoms of dementia (BPSD) in patients with Alzheimer's disease (AD).MethodsOne hundred and two AD patients complaining of BPSD were followed-up for 12 months after being well controlled. Potential risk factors for the recurrence of BPSD were evaluated. The severity of BPSD was measured using the Neuropsychiatric Inventory (NPI). NPI syndromes were categorized into affective impairments, psychotic symptoms, and lack of control disorders. Characteristics of the recurrent BPSD were compared with those of the former onset.ResultsForty-five of the patients presented recurrent BPSD within 12 months. Risk factors of recurrence included change of environment (RR = 5.42, p < 0.001), failure to maintain antipsychotic medication (RR = 3.13, p < 0.001), and high NPI score (RR = 1.06, p = 0.023) at the former onset. Both the number of symptoms and the affective subscores were correlated (r = 0.93, p = 0.011; r = 0.79, p = 0.016, respectively) and showed no significant difference between the two adjacent onsets of BPSD. The NPI total score (18.29 ± 2.06 vs. 20.80 ± 3.78, p = 0.031) and the psychotic subscore (6.49 ± 1.80 vs. 7.73 ± 1.92, p = 0.033) were significantly lower in the recurrent onset than those in the former and the two values showed no significant correlation between the two onsets. Subscores of lack of control of the two onsets were neither correlated nor different statistically from each other.ConclusionChange of environment, failure to maintain antipsychotic medication, and high NPI score at the former onset are risk factors for the recurrence of BPSD. Profiles of two onsets in the same patient are not always the same. The severity of BPSD and its psychotic symptoms show a tendency to ameliorate with the progression of AD. Affective impairments appear to be consistent. Lack of control disorders may be variable.