BACKGROUND: Research on terminal decline has widely documented that cognitive performance steeply declines with nearing death. To date, it is unclear whether these changes are normative, based on pathologies associated with (preclinical) dementia, or both.
OBJECTIVES: We analyzed heterogeneity in trajectories of terminal cognitive change in Swiss nursing home residents with the objective of examining whether terminal change is normative or whether one or multiple subgroup(s) with relative stability exist.
METHODS: We performed a longitudinal analysis based on routine assessments with the Resident Assessment Instrument - Minimal Data Set in 341 nursing homes between 1998 and 2014. In sum, we used 143,052 observations from 30,054 residents (69% women, average age at death 87 years) in the last 3 years of life. We analyzed trajectories of the Cognitive Performance Scale (CPS) score with latent class growth curve models and examined sociodemographic factors (age at death, sex, marital status, prior living situation) as well as functional and mental health (Activities of Daily Living Index and Depression Rating Scale) and dementia diagnosis as correlates of group membership.
RESULTS: We identified three distinct classes based on longitudinal trajectories of the CPS score. In the first group (transition from no to mild impairment, 27%), cognitive impairment increased with time to death (linear and quadratic), but remained at relatively mild levels at all times. The trajectories of the second group (transition from moderate to severe impairment, 43%) were characterized by linear and quadratic changes across time to death. The trajectories of the third group (severe impairment, 30%) were characterized by the lowest amount of linear increase across all groups and no quadratic increase indicating no accelerated change. Better functional health and absence of a dementia diagnosis predicted less impairment. Fewer depressive symptoms were associated with low as opposed to moderate or severe, but also severe versus moderate impairment.
CONCLUSION: Our findings suggest that the majority of residents experience terminal change, with the exception of those at already high levels of impairment. Furthermore, late-life cognitive change is related to functional and mental health.