Protein-energy undernutrition and the risk of mortality within one year of hospital discharge: a follow-up study.

OBJECTIVE

The primary objective of this study was to confirm the results of a previous study that demonstrated a strong independent correlation between the severity of protein-energy undernutrition and the risk of 1-year postdischarge mortality in a population of older rehabilitation patients.

DESIGN

Prospective survey (cohort study).

SETTING

The Geriatric Rehabilitation Unit (GRU) of a Veterans Administration hospital.

PARTICIPANTS

Of 350 randomly selected admissions to the GRU, 322 were discharged alive from the hospital. These 322 patients represented the study population, of whom 99% were male, and 75% were white. The average age of the study patients was 76 years.

MEASUREMENTS

At admission and again at discharge, each patient completed a comprehensive medical, functional, neuropsychological, socioeconomic, and nutritional assessment. After discharge, each subject was tracked for 1 year.

MAIN RESULTS

Within the 1-year posthospital discharge follow-up period, 64 study subjects (20%) died. This included 17% of the patients discharged home and 34% of the patients discharged to a nursing home (P < .01). Based on the Cox Proportional Hazards survival model, the variable most strongly associated with mortality was the discharge serum albumin, followed by discharge weight expressed as a percentage of ideal, self-dressing ability, and a discharge diagnosis of cardiac arrhythmia (usually atrial fibrillation). When all four of these variables were included in the analysis, the model was able to differentiate the survivors from those who died by years end with a sensitivity of 69%, a specificity of 69%, and an overall predictive accuracy of 69%. When tested using the data from the previous study, the model differentiated the patients who died from those who had not at a sensitivity of 62%, a specificity of 68%, and an overall predictive accuracy of 64%.

CONCLUSIONS

Protein-energy undernutrition appears to be a strong independent risk factor for 1-year postdischarge mortality.