The Nursing Home Pneumonia Risk Index: A Simple, Valid MDS-Based Method of Identifying 6-Month Risk for Pneumonia and Mortality.

BACKGROUND

Pneumonia is the leading infectious cause of hospitalization and death for nursing home (NH) residents; however, diagnosis is often delayed because classic signs of infection are not present. We sought to identify NH residents at high risk for pneumonia, to identify persons to target for more intensive surveillance and preventive measures.

METHODS

Based on a literature review, we identified key risk factors for pneumonia and compiled them for use as prediction tool, limiting risk factors to those available on the Minimum Data Set (MDS). Next, we tested the tool's ability to predict 6-month pneumonia incidence and mortality rates in a sample of 674 residents from 7 NHs, evaluating it both as a continuous and a dichotomous variable, and applying both logistic regression and survival analysis to calculate estimates.

RESULTS

NH Pneumonia Risk Index scores ranged from -1 to 6, with a mean of 2.1, a median of 2, and a mode of 2. For the outcome of pneumonia, a 1-point increase in the index was associated with a risk odds ratio of 1.26 (P = .038) or a hazard ratio of 1.24 (P = .037); using it as a dichotomous variable (≤2 vs ≥3), the corresponding figures were a risk odds ratio of 1.78 (P = .045) and a hazard ratio of 1.82 (P = .025). For the outcome of mortality, a 1-point increase in the NH Pneumonia Risk Index was associated with a risk odds ratio of 1.58 (P = .002) and a hazard ratio of 1.45 (P = .013); using the index as a dichotomous variable, the corresponding figures were a risk odds ratio of 3.71 (P < .001) and a hazard ratio of 3.29 (P = .001).

CONCLUSIONS

The NH Pneumonia Risk Index can be used by NH staff to identify residents for whom to apply especially intensive preventive measures and surveillance. Because of its strong association with mortality, the index may also be valuable in care planning and discussion of advance directives.