Background: COPD is a leading cause of death and disability in the United States. Patients with COPD are at a high risk of nutritional deficiency, which is associated with declines in respiratory function, lean body mass and strength, and immune function. Although oral nutritional supplementation (ONS) has been associated with improvements in some of these domains, the impact of hospital ONS on readmission risk, length of stay (LOS), and cost among hospitalized patients is unknown.
Methods: Using the Premier Research Database, we first identified Medicare patients aged ≥ 65 years hospitalized with a primary diagnosis of COPD. We then identified hospitalizations in which ONS was provided, and used propensity-score matching to compare LOS, hospitalization cost, and 30-day readmission rates in a one-to-one matched sample of ONS and non-ONS hospitalizations. To further address selection bias among patients prescribed ONS, we also used instrumental variables analysis to study the association of ONS with study outcomes. Model covariates included patient and provider characteristics and a time trend.
Results: Out of 10,322 ONS hospitalizations and 368,097 non-ONS hospitalizations, a one-to-one matched sample was created (N = 14,326). In unadjusted comparisons in the matched sample, ONS use was associated with longer LOS (8.7 days vs 6.9 days, P < .0001), higher hospitalization cost ($14,223 vs $9,340, P < .0001), and lower readmission rates (24.8% vs 26.6%, P = .0116). However, in instrumental variables analysis, ONS use was associated with a 1.9-day (21.5%) decrease in LOS, from 8.8 to 6.9 days (P < .01); a hospitalization cost reduction of $1,570 (12.5%), from $12,523 to $10,953 (P < .01); and a 13.1% decrease in probability of 30-day readmission, from 0.34 to 0.29 (P < .01).
Conclusions: ONS may be associated with reduced LOS, hospitalization cost, and readmission risk in hospitalized Medicare patients with COPD.