Dementia, lower respiratory tract infection, and long-term mortality.

OBJECTIVE

To examine long-term mortality and its determinants in nursing home residents with dementia diagnosed with a lower respiratory tract infection (LRI).

SETTING AND PATIENTS

US (Missouri) nursing home residents (541) and Dutch residents (403) with dementia who were treated with antibiotics for an LRI.

METHODS

Prospective studies of nursing home-acquired LRI in the US (Missouri) and in the Netherlands. Measurements included demographics, indicators of acute illness, general health condition, intake problems, and comorbid disease. Six-month mortality rates were calculated and Cox proportional hazards models were developed for mortality up to 2 years after diagnosis.

RESULTS

Six-month mortality was 48.8% among Dutch residents and 36.4% among US residents. After multivariable adjustment, Dutch nationality was not associated with higher long-term mortality. Variables most strongly associated with long-term mortality were activity of daily living dependency and male gender. Other variables associated with outcome were diverse: respiratory difficulty, age, dehydration, congestive heart failure, decreased alertness, decubitus ulcers, Parkinson disease, weight loss/poor nutrition, and pulse rate.

CONCLUSION

LRI is followed by substantial mortality in the months after diagnosis, indicating high frailty of nursing home residents with dementia who develop LRI. A variety of patient characteristics, including many not directly related to LRI, were consistently associated with long-term mortality in two cohorts with differing illness severity. The results are relevant for informing families, evaluating poor long-term survival in the context of care and treatment, and balancing the potential burdens and benefits of care.