Dementia severity, decline and improvement after a lower respiratory tract infection.

Objective: To assess decline and improvement in functional characteristics, cognition and restraint use after a lower respiratory tract infection (LRI) and describe variation by dementia severity. Design: Two prospective cohort studies. Setting: Nursing homes in the Netherlands and in Missouri, USA. Participants: 227 Dutch and 396 Missouri nursing home residents with dementia and LRI who were treated with antibiotics. Measurements: We compared functional characteristics (Activities of Daily Living [ADL], bedfast status, pressure ulcers, incontinence), cognition and restraint use 3 months after an LRI with status 1 to 2 weeks before diagnosis. Results: Residents with LRI frequently declined on all measures, but many also improved, including those with severe dementia. On the measures where residents could still decline further, residents with severe dementia showed higher variability than residents with less severe dementia. This was most obvious for bedfast status and restraint use. Conclusions: Compared with less severely demented residents, residents with severe dementia showed more decline on measures where they still had room for change. However, on these measures, residents with severe dementia also improved more often. LRI does not necessarily lead to deterioration even in individuals with severe dementia.