This prospective study furthers our understanding of the practical aspects of estimating prognosis in advanced dementia. When administered at the bedside, the ADEPT risk score had high interrater reliability, good calibration, and modest discrimination in predicting 6-month survival when applied as a continuous measure (AUROC=0.67). Medicare hospice eligibility guidelines also had excellent interrater reliability, but the discrimination was poor (AUROC=0.55). The ADEPT score’s performance was not significantly different (AUROC = 0.58) when examined as a dichotomous measure using a cutoff with the same specificity as hospice guidelines. These findings underscore the challenge of prognostication in advanced dementia and suggest that determining access to hospice based on life expectancy for patients with dementia limits access to the supportive care hospice offers.
The characteristics of the residents with advanced dementia in this cohort were comparable with other studies.4,7,8,16,19,34
In particular, almost all ADEPT score items ascertained using primary data collection were similarly distributed in the derivation cohort, defined, and characterized using secondary MDS data.16
One exception was that fewer residents in the prospective cohort were recent admissions compared with the derivation cohort (4.8% vs 36.2%), albeit the definition of this variable differed slightly between the 2 studies. The 6-month mortality rate was lower in the prospective cohort (18% vs 25%), possibly reflecting the inclusion of fewer recent admissions. Fewer residents in the prospective study met hospice eligibility compared with the derivation cohort (11% vs 16%), in which criteria were simulated with MDS data. Taken together, dissimilarities between the prospective validation and retrospective derivation cohorts may be attributable to both differences in resident characteristics, as well as variation in data ascertainment methods.
Despite the few cohort differences, the discrimination of the ADEPT score to predict 6-month survival in this prospective validation was comparable with its performance in the retrospective derivation data set (AUROC=0.68).16
The ADEPT score demonstrated good calibration. However, in practice, whether to use the predicted mortality rates in this smaller prospective cohort vs those in the larger derivation cohort is debatable. Because values differed primarily in the 2 highest risk categories, it may be reasonable to consider the probability of death in these categories to be within the range of the 2 mean predicted values (eg, >16.1 points; 0.49-0.62).
Hospice eligibility guidelines for dementia are widely used, but have never been validated in a large, prospective fashion. In corroboration with prior retrospective studies, we found the discrimination of hospice guidelines to predict 6-month mortality was poor.4,16
However, using a single cutoff to estimate 6-month prognosis, whether using existing hospice guidelines or the empirically derived ADEPT score, is problematic for determining which nursing home residents with advanced dementia should receive hospice care. For example, using a relatively low cutoff score of more than 7.9, 91.9% of residents with advanced dementia who died within 6 months would be eligible for the program (sensitivity), but only 22.3% of enrolled residents would die within that period (positive predictive value). With a high cutoff score of more than 16.1, only 9.0% of residents who died within 6 months would be eligible, but 45.5% of enrolled residents would die within that same period. That said, one potential advantage of the ADEPT score is that as a continuous measure, it offers physicians and other primary care clinicians caring for these patients (eg, nurse practitioners) flexibility to select cutoffs with different operating characteristics (ie, tradeoff between sensitivity and specificity).
There are several limitations to our study that warrant comment. First, it is possible that the ADEPT score did not capture clinical variables strongly predictive of mortality. However, given the comprehensiveness of the MDS, the rigor of our approach, and the consistency of our findings with earlier research,4,5,7,8,16,18,19
the degree to which the accuracy of a mortality risk score for advanced dementia could be improved with additional variables is questionable. Second, the ADEPT score and hospice eligibility were ascertained at a single random time point in the residents’ course. In practice, hospice referrals are often initiated when care preferences shift toward comfort following a clinical set-back. Third, our prospective cohort was predominantly white and lived in Boston-area facilities, potentially limiting the generalizabilty of our findings. In addition, the ADEPT score was derived and validated in nursing home residents. Although the majority of patients with dementia die in nursing homes,35
the ADEPT score has not been validated for those patients in the community.
Dementia is a leading cause of death in the United States.36
Similar to other terminally ill patients, persons with advanced dementia commonly experience burdensome symptoms (eg, pain, dyspnea).37
Our study strongly suggests that delivery of palliative care to these residents should be guided by a preference for comfort as the primary goal of care and not by prognostic estimates. Therefore, the challenge for health care professionals and policy makers is to ensure that high-quality palliative care is accessible to the growing number of individuals dying with dementia in nursing homes, an effort that may necessitate both revisiting the 6-month prognosis requirement for hospice, as well as expanding comprehensive palliative care services in the nursing home.