Concurrent validity of neuropsychiatric subgroups on caregiver burden in Alzheimer disease patients.

OBJECTIVE: In a previously published study, the authors conceptualized neuropsychiatric symptoms in Alzheimer disease (AD) patients as distinct symptom profiles with differential outcomes. In the present study, our aim was to further examine the validation of the classification by considering its concurrent validity on caregiver burden. METHOD: As described previously, neuropsychiatric symptoms, as assessed by the Neuropsychiatric Inventory, in 122 patients with AD were categorized, using cluster analysis. The presence as well as the severity and frequency of symptoms were both used in the classification. After the classification, group differences in caregiver burden, as measured by Screen for Caregiver Burden, were tested using analysis of covariance. The effects of important covariates, such as functional impairment, comorbid medical conditions, parkinsonism, age, and cognitive functioning, were examined. RESULTS: Based on the presence of symptoms, subgroups differed in the level of caregiver distress in that caregivers of the "minimally symptomatic" and the "affective/apathetic" subgroups experienced less distress than the caregivers of the "highly symptomatic" subgroup. Based on the severity and frequency of symptoms, subgroups differed in such a way that caregivers of the "minimally symptomatic" and the "predominantly apathetic" subgroups endorsed less distress than the caregivers of the "affective" and the "highly symptomatic" subgroups. CONCLUSION: Neuropsychiatric subgroups were able to differentially predict caregiver burden. The findings appear to lend further support to the validity of classifying neuropsychiatric symptoms in AD patients using cluster analysis.

MMPI-2 profiles: fibromyalgia patients compared to epileptic and non-epileptic seizure patients.

We compared MMPI-2 profiles of Gulf War veterans with fibromyalgia (FM) to epileptic seizure (ES) patients, psychogenic non-epileptic seizure (PNES) patients, and Gulf War veteran healthy controls. Both PNES and FM are medically unexplained conditions. In previous MMPI-2 research PNES patients were shown to have significantly higher Hs and Hy clinical scales than ES patients. In the present research the FM group had significantly higher Hs and Hy scale scores than both the ES group and the healthy control group. There was no significant difference between the FM and PNES Hs scale scores; however, the FM Hy scale score was significantly lower than the PNES Hy scale score. Present findings indicate a high level of psychological distress in the FM group.

Predictive validity of neuropsychiatric subgroups on nursing home placement and survival in patients with Alzheimer disease.

OBJECTIVE: The aim of the study was to conceptualize neuropsychiatric symptoms in patients with Alzheimer disease as distinct symptom profiles with differential disease outcomes. Two outcomes of interest in the study were nursing home placement and survival. METHOD: Cluster analysis was used to categorize 122 patients with Alzheimer disease based on their neuropsychiatric symptoms as assessed by the Neuropsychiatric Inventory. Both the presence as well as the severity and frequency of symptoms were considered. After identification of the subgroups, the predictive validity of the categorization was tested on time to nursing home placement and time to death over a three-year period. Cox proportional hazard models were used to perform survival analysis. Important covariates such as severity of cognitive and functional impairments, comorbid medical conditions, presence of parkinsonism, and marital status were adjusted at baseline. RESULTS: Based on the presence of neuropsychiatric symptoms, three subgroups were identified: minimally symptomatic, highly symptomatic, and affective/apathetic. Over a three-year period, the highly symptomatic group had an increased risk of nursing home placement. In addition, the rates of survival were significantly lower for the highly symptomatic and the affective/apathetic subgroups. Based on the severity and frequency of symptoms, two-cluster and four-cluster solutions were produced. The groupings based on severity and frequency of symptoms predicted significant differential outcomes in survival and nursing home placement. CONCLUSIONS: Neuropsychiatric subgroups were able to predict differential outcomes and identify those with an increased risk for a worse prognosis. The findings were discussed through their research and clinical implications.