Delirium Superimposed on Dementia Strongly Predicts Worse Outcomes in Older Rehabilitation Inpatients

Abstract

ObjectiveDelirium superimposed on dementia (DSD) is common in many settings. Nonetheless, little is known about the association between DSD and clinical outcomes. The study aim was to evaluate the association between DSD and related adverse outcomes at discharge from rehabilitation and at 1-year follow-up in older inpatients undergoing rehabilitation.DesignProspective cohort study.SettingHospital rehabilitation unit.ParticipantsA total of 2642 patients aged 65 years or older admitted between January 2002 and December 2006.MeasurementsDementia predating rehabilitation admission was detected by DSM-III-R criteria. Delirium was diagnosed with the DSM-IV-TR. The primary outcome was that of walking dependence (Barthel Index mobility subitem score of <15) captured as a trajectory from discharge to 1-year follow-up. A mixed-effects multivariate logistic regression model was used to analyze the association between DSD and outcome, after adjusting for relevant covariates. Secondary outcomes were institutionalization and mortality at 1-year follow-up, and logistic regression models were used to analyze these associations.ResultsThe median age was 77 years (interquartile range: 71–83). The prevalence of DSD was 8%, and the prevalence of delirium and dementia alone were 4% and 22%, respectively. DSD at admission was found to be significantly associated with almost a 15-fold increase in the odds of walking dependence (odds ratio [OR] 15.5; 95% Confidence Interval [CI] 5.6–42.7; P < .01). DSD was also significantly associated with a fivefold increase in the risk of institutionalization (OR 5.0; 95% CI 2.8–8.9; P < .01) and an almost twofold increase in the risk of mortality (OR 1.8; 95% CI 1.1–2.8; P = .01).ConclusionsDSD is a strong predictor of functional dependence, institutionalization, and mortality in older patients admitted to a rehabilitation setting, suggesting that strategies to detect DSD routinely in practice should be developed and DSD should be included in prognostic models of health care.

Risk Factors and Outcomes of Delirium in Older Patients Admitted to Postacute Care with and without Dementia

“…In fact, compared to these 3 studies, the mean age of patients with dementia in our study was much higher, probably raising the mortality rate of those with dementia without delirium and attenuating differences compared to DSD. Regarding functional evolution, our results are consistent with those of previous studies [31, 35, 36], showing a greater functional decline among patients with delirium, and also with Morandi et al [20], who observed a greater disability in patients that developed DSD than in those with only dementia or only delirium in a hospital rehabilitation setting.…”

“…Among factors predisposing to delirium, dementia appears to be the most consistent in hospitalized patients [13, 14], and the prevalence of delirium superimposed on dementia (DSD) is almost 90% in some hospital-based studies [15-17]. Patients who develop DSD have an increased risk of longer hospital stay, morbidity, acceleration of cognitive and functional decline, institutionalization, and mortality [18-20]. …”

The Association Between the Probability of Sarcopenia and Functional Outcomes in Older Patients Undergoing In-Hospital Rehabilitation

“…This in-hospital rehabilitation setting has been fully described elsewhere. 17,18 Briefly, the rehabilitation ward is staffed by full-time geriatricians, psychiatrists, nurses, nurse aides, and physical, speech, and occupational therapists. Patients were excluded if they were unable to complete study assessments because of delirium, comatose state, or aphasia, based on medical record documentation.…”

Association Between Statin Use at Admission to Inpatient Rehabilitation and Functional Status at Discharge among Older Patients

“…Delirium has been previously described to be negatively associated with functional status in older patients admitted to rehabilitation settings and, in particular, when delirium occurs in the context of dementia. [27][28][29] Conversely, the literature on the association between ACE inhibitors and functional status is controversial. Observational studies have shown that the use of ACE inhibitors is associated with a slower decline in muscle mass, muscle strength, and walking speed in older communitydwelling subjects, suggesting a direct role of these medications on skeletal muscle.…”