Placement and mortality among AD patients are sentinel outcomes important to both clinicians and family members. They also have far-reaching policy implications because of the high costs of long-term care on the one hand and the detrimental health effects of being an AD caregiver on the other21
. Improving our understanding of factors that contribute to these outcomes can help clinicians and family members anticipate and plan for these events and inform patient and caregiver interventions. The findings of this study enhance our understanding of AD patient placement and mortality in four areas.
First, our findings reveal important differences between death and placement when compared to continued home care. Both death and placement are associated with increased ADL limitations, having a non-spouse caregiver, and being a male and patient. They differ with respect to health service use, race, and group assignment. Compared to persons who remain at home, patients who are placed are more likely to be White as opposed to African American or Hispanic; caregiver assignment to the control condition as opposed to active treatment and increasing patient health service use are associated with increased mortality. Placed and deceased patients are further differentiated from each other by the fact that caregivers of placed patients report increased levels of being bothered by memory problems when compared to caregivers of deceased patients. The picture that emerges from these analyses is that increasing functional declines as measured by limitations in ADL are associated with both placement and death. However, increases in caregiver reports of being bothered by memory problems are associated with placement, while increases in patient health service use are associated with death. Increasing health service use may contribute to a reduction in memory-related behavior problems, thus causing less upset about memory problems; alternatively, increasing memory problems or at least their increasing negative impact on the caregiver may be causally linked to the caregiver’s decision to institutionalize their relative. These findings suggest that placed patients may be at earlier stages of the illness where memory problems are salient to the caregiver while those who die are at a later stage, characterized by higher levels of disability and more comorbidities. Of note, patient problem behaviors as measured by the RMBPC are not significantly related to either placement or death.
Our findings that death is associated with increased health service utilization are consistent with those of Newcomer et al.9
, showing that increased use of health services such as visiting nurses, physician visits, and emergency rooms along with increased ADL limitations may be an important signal of impending death for AD patients being cared for at home. A closer examination of the types of services used by our patients shows that the change is primarily due to increased visits to a physician and nurses visits as opposed to emergency room visits, hospitalizations, or short-term nursing home stays. The combination of increasing medical problems and decreasing memory problems may be a useful predictor of impending death among AD patients residing in the community.
Second, our findings show that risk factors for mortality and placement in AD patients vary depending on which reference group is used. For example, decreases in being bothered by memory problems predict mortality when placement is used as the comparison group, but this factor does not differentiate mortality from continued community residence. These findings are consistent with conclusions reached by other investigators pointing out that risk factors for AD outcomes may vary widely depending on the populations studied, whether one includes incident or prevalent cases, location in a disease trajectory, and length of follow-up5, 7
. Our findings underscore the choice of reference group as a factor in predictive models of AD outcomes. The implications of the choice of reference group and findings are a critical factor when comparing information across studies. Additionally, the differences highlight the possibility that the large number of risk factors may interact in complex ways toward a particular end-point.
Third, the literature consistently shows that African American and Hispanic caregivers are less likely than Whites22
to institutionalize their relative with AD, in part because minorities have less access to this resource, different family structure, proximity of family members, and different attitudes toward institutionalization23
. Our findings also demonstrate this effect. To shed more light on these findings, we explored interactions between race/ethnicity and patient/caregiver variables but found no statistically significant interaction effects. Determining the underlying factors behind these institutionalization differences remains an important question for future research as the findings may enable longer community residence of AD patients of all race/ethnic backgrounds. One possibility is that these race/ethnicity differences are mediated by caregiver coping style or intensity of involvement in caregiving6
Fourth, we show that survival was associated with being assigned to an active intervention condition. A similar finding was reported by Brodaty et al.4
, but ours is different in two respects. First, we focus only on deaths that occur while the patient is still at home being cared for by a family caregiver, whereas Brodaty4
include deaths that occur after nursing home placement. Thus, our mortality effect is not mediated by placement and shows that death at home is conceptually different from death in a nursing home and the two should not be combined. Second, the intervention effect on survival appears only after we include change variables in the analysis, suggesting that changes in health service use, memory problems, and ADL limitations unmask the effects of intervention. In contrast, the Brodaty et al.4
study found that including change variables eliminated the intervention mortality effect, suggesting the survival was mediated by intervention-related reductions in caregiver distress. Our findings are more difficult to explain and may be related to the comparatively high mortality rates during the first six months among individuals assigned to intervention condition. Since these individuals were not included in our longitudinal analysis, our findings may reflect the selective impact of psychosocial interventions on caregivers providing support to patients who were relatively robust. Another possibility is that caregivers who received an intervention delivered more effective care. This is an intriguing finding that deserves follow-up in future studies of AD mortality and caregiver interventions.
Finally, we note a number of limitations of our study. Most of the patient status variables used in this analysis are based on caregiver reports and may be influenced the nature of the caregiving experience. The analysis would have been enriched by additional objective patient status indicators. However, the caregiver plays an important role in the outcomes of interest. It could, therefore, be argued that their perspective is paramount in developing predictive models of placement and mortality. As is the case for all descriptive studies, we cannot assume causality between predictor and outcome variables. Nevertheless, the consistency and logic of findings in our cross-sectional and longitudinal analysis argue strongly for some causal relationships. For example, it seems reasonable to conclude that the caregiver’s level of upset or bother with problem behaviors of the patient is an important factor in the decision to place the patient in a long-term care facility.