Patient Factors Systematically Influence Hospital Length of Stay in Common Orthopaedic Procedures

As the United States healthcare system evolves towards improved value delivery, patient outcomes and healthcare costs are increasingly used to evaluate physicians and provider organizations. One such metric is hospital length of stay, which has the potential to be influenced by a variety of patient characteristics and comorbidities. Determining factors influencing length of stay represents an opportunity to increase value in healthcare delivery.

The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database (2006-2012) was utilized to identify a cohort of 92,266 patients having one of 14 common orthopaedic procedures. A generalized linear model was utilized to identify patient factors that increase hospital length of stay.

During the six-year study period, length of stay decreased significantly in the total joint arthroplasty population. Nine variables were independently associated with increased length of stay. Congestive heart failure and underweight status increased length of stay the most, at 1.46 and 1.01 days, respectively. Other factors increasing length of stay include: non-white race (0.69 days), chronic obstructive pulmonary disease (0.50 days), diabetes mellitus (0.25 days), morbid obesity (0.23 days), hypertension (0.10 days), and patient age (0.02 days for each additional year).

In conclusion, congestive heart failure and underweight status are the greatest predictors of increased length of stay. COPD, diabetes, morbid obesity, and hypertension represent other modifiable risk factors that increase length of stay. This data can be used to counsel patients and their families regarding anticipated duration of hospitalization. Systematic targeting of patient factors known to increase length of stay represents an opportunity for cost reduction and improved value delivery. When utilizing hospital length of stay as a metric for evaluation, it is important to incorporate the factors that increase length of stay, so that orthopaedic surgeons and provider organizations can be evaluated based on representative patient population characteristics.