The effect of pre-hospital ADL trajectory on post-hospital ADL trajectory and mortality
Jane Banaszak-Holl, University of Michigan 
Orna Intrator, Brown University 
*Robin L. Kruse, University of Missouri 
David R. Mehr, University of Missouri 
Gregory F. Petroski, University of Missouri 

Keywords: ADL trajectory, hierarchical models, acute hospitalization

Background: Activities of Daily Living (ADL)—personal care activities such as dressing and eating—provide key indicators of health, mortality risk, and quality of life for nursing home residents. It has been hypothesized that ADL trajectories may provide information about nursing home residents’ prognoses, particularly how prognoses might be altered following hospitalization. Methods: National Minimum Data Set (MDS) assessments and Medicare inpatient eligibility and claims for 2006-2007 were used to select long-stay nursing home residents (354,054) with 2 or more MDSs before hospital admission and no prior hospital stays for at least 90 days. Seven ADL items were summed to derive a 0-28 point score (28=worst impairment). We used hierarchical models to derive predicted pre- and post-hospital trajectories of ADL. We defined stable trajectory as a slope between -3 and 3 units per year. Results: Before admission, 67.9% of residents had stable ADL trajectories, 18.7% were improving, and 13.4% were worsening. For residents with 2 or more post-hospital MDSs, stability was the most common pattern (46.4%), followed by improvement (44.3%) and decline (9.3%). Among residents with initial scores below 15, improvement was the most common post-hospital trajectory, regardless of initial trajectory. For residents with initial scores of 15-24, post-hospital improvement was most common among those with pre-hospital improvement (55.2%), while post-hospital stability characterized residents with stable (55.6%) or worsening (59.8%) pre-hospital trajectories. Stable trajectories representing high impairment dominated the post-hospital period for residents with initial scores above 24 (82.7%), regardless of pre-hospital trajectory. The highest proportions of improving post-hospital trajectories occurred in residents with hip fracture (57.8%) and CHF (52.6%), while residents with aspiration pneumonitis were most often stable (60.4%). Mortality within 30 days of hospital discharge (23.2%) was related to pre-hospital trajectory: improving (18.8%), stable (23.3%), and worsening (29.1%). Discussion: Among survivors, there is more improvement than decline post-hospitalization. Pre-hospital ADL trajectories were associated with post-hospital outcomes, and varied by diagnoses. These results could be very important in light of developing changes in how Medicare pays for care and the possibility that an episode of care will include both the nursing home and hospital services.