Objectives: To assess the effect of inpatient oral nutritional supplement (ONS) use on length of stay, episode cost, and 30-day readmission probability.
Study design: Eleven-year retrospective study (2000 to 2010).
Methods: Analyses were conducted using the Premier Perspectives Database, which contained information on 44.0 million adult inpatient episodes. Using a matched sample of ONS and non-ONS episodes for any inpatient diagnosis, instrumental variables regression analysis was performed to quantify the effect of ONS use on length of stay, episode cost, and probability of approximate 30-day readmission. For the readmission outcome, the matched sample was restricted to episodes where the patient was known to be at risk of readmission. The fraction of a hospital's episodes in a given quarter involving ONS was used as an instrumental variable.
Results: Within the database, 1.6% of 44.0 million adult inpatient episodes involved ONS use. Based on a matched sample of 1.2 million episodes, ONS patients had a shorter length of stay by 2.3 days (95% confidence interval [CI] - 2.42 to -2.16), from 10.9 to 8.6 days (21.0% decline), and decreased episode cost of $4734 (95% CI - $4754 to - $4714), from $21,950 to $17,216 (21.6% decline). Restricting the matched sample to the 862,960 episodes where patients were readmitted at some point, ONS patients had a reduced probability of early readmission (within 30 days) of 2.3 percentage points (95% CI - 0.027 to - 0.019), from 34.3% to 32.0% (6.7% decline).
Conclusions: Use of ONS decreases length of stay, episode cost, and 30-day readmission risk in the inpatient population.