Interaction between cognitive impairment and discharge destination and its effect on rehospitalization.
OBJECTIVE
To evaluate the effect of cognitive impairment on rehospitalization in older adults.


METHODS
One-year longitudinal study.


METHODS
Medical service of an urban, 340-bed public hospital in Indianapolis between July 2006 and March 2008.


METHODS
Individuals aged 65 and older admitted to the medical service (N = 976).


METHODS
Rehospitalization was defined as any hospital admission after the index admission. Participant demographics, discharge destination, Charlson Comorbidity Index, Acute Physiology Score, and prior hospitalizations were measured as the confounders. Participants were considered to have cognitive impairment if they had two or more errors on the Short Portable Mental Status Questionnaire.


RESULTS
After adjusting for confounders, a significant interaction between cognitive impairment and discharge location was found to predict rehospitalization rate (P = .008) and time to 1-year rehospitalization (P = .03). Participants with cognitive impairment discharged to a facility had a longer time to rehospitalization (median 142 days) than participants with no cognitive impairment (median 98 days) (hazard ratio (HR) = 0.77, 95% confidence interval (CI) = 0.58-1.02, P = .07), whereas participants with cognitive impairment discharged to home had a slightly shorter time to rehospitalization (median 182 days) than those without cognitive impairment (median 224 days) (HR = 1.15, 95% CI = 0.92-1.43, P = .23). These two nonsignificant HRs in opposite directions were significantly different from each other (P = .03).


CONCLUSIONS
Discharge destination modifies the association between cognitive impairment and rehospitalization. Of participants discharged to a facility, those without cognitive impairment had higher rehospitalization rates, whereas the rates were similar between cognitively impaired and intact participants discharged to the community.
School of Medicine, Indiana University, Indianapolis, Indiana.
Arif
A
Nazir
Michael
M
LaMantia
Joshua
J
Chodosh
Babar
B
Khan
Noll
N
Campbell
Siu
S
Hui
Malaz
M
Boustani
D000368:Aged; D003072:Cognition Disorders / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D010351:Patient Discharge; D010359:Patient Readmission / Q000706:statistics & numerical data*
cognitive impairment; discharge destination; rehospitalization