Both these studies included patients with dementia but did not specifically investigate the outcomes associated to

DSD compared with the dementia or delirium-alone subgroups. These results provide new knowledge about the possible prognostic role of DSD in patients undergoing rehabilitation, in that DSD was strongly linked to adverse outcomes. The association between DSD and adverse outcomes underlines the clinical importance of its effect. It remains uncertain if DSD is worse than delirium or dementia alone, as suggested by the differences in the ORs and as described by the distribution of mobility dependence in Figure 1. A larger study would be required to test this association adequately. Previous investigations have reported that patients with DSD, compared with patients with dementia and delirium alone, have a twofold increased risk of being institutionalized at discharge and more than a twofold increase in the risk of mortality in the 12 months after discharge from Z-VAD-FMK chemical structure a rehabilitation setting.3 and 25 Additionally, in acute hospitals, patients with DSD compared with patients with dementia alone were exposed to a higher risk of short-, medium-, and long-term functional decline and short-term mortality.17 and 18 Acutely hospitalized patients with DSD carry a significantly higher risk of institutionalization at 1-year follow-up than those with neither delirium nor dementia.18

In our population, the presence of DSD at the time of admission was associated with increased selleck products 1-year mortality and institutionalization rates, consistent with previous data on the effect of DSD on mortality in a smaller cohort25 and the reported effect of DSD on institutionalization in acutely hospitalized elderly patients.17 and 18 Similar to the effect on institutionalization and mortality, in our population, DSD had an additive effect on the ability

to walk independently at discharge and at 1-year follow-up for the patients with DSD and dementia alone. The findings of worse outcomes related to DSD might be explained by reference to the pathophysiology of delirium in patients with dementia. Dementia is one of the biggest predisposing risk factors for delirium, and in this population, systemic inflammation, caused by infection, injury or surgery, is one of the major triggers.35 and 36 According to the model proposed by Inouye and colleagues,37 severe precipitants PAK5 are required to precipitate delirium in healthy populations, whereas much milder stimuli can trigger a delirious episode in patients with preexisting dementia. In these patients, even a mild infection can be the main trigger for delirium and the occurrence of DSD could lead to a more rapid cognitive decline than dementia alone, suggesting that the primary insult that causes delirium may directly exacerbate the underlying cognitive impairment.38 and 39 The worsening of the cognitive impairment due to delirium could then be responsible for the worse functional outcomes seen in our study.