Impact and recognition of cognitive impairment among hospitalized elders.

Background: Older adults are predisposed to developing cognitive deficits. This increases their vulnerability for adverse health outcomes when hospitalized.

Objective: To determine the prevalence and impact of cognitive impairment (CI) among hospitalized elders based on recognition by lCD-coding versus screening done on admission.

Design: Observational cohort study.

Setting: Urban public hospital in Indianapolis.

Patients: 997 patients age 65 and older admitted to medical services between July 2006 and March 2008.

Measurements: Impact of CI in terms of length of stay, survival, quality of care and prescribing practices. Cognition was assessed by the Short Portable Mental Status Questionnaire (SPMSQ).

Results: 424 patients (43%) were cognitively impaired. Of those 424 patients with CI, 61% had not been recognized by ICD-9 coding. Those unrecognized were younger (mean age 76.1 vs. 79.1, P <0.001); had more comorbidity (mean Charlson index of 2.3 vs.1.9, P = 0.03), had less cognitive deficit (mean SPMSQ 6.3 vs. 3.4, P < 0.001). Among elders with CI, 163 (38%) had at least one day of delirium during their hospital course. Patients with delirium stayed longer in the hospital (9.2 days vs. 5.9, P < 0.001); were more likely to be discharged into institutional settings (75% vs. 31%, P < 0.001) and more likely to receive tethers during their care (89% vs. 69%, P < 0.001), and had higher mortality (9% vs. 4%, P = 0.09).

Conclusion: Cognitive impairment, while common in hospitalized elders, is under-recognized, impacts care, and increases risk for adverse health outcomes.