Weight Loss Shortens Hospital Stays, Improves Outcomes for Obese Knee Surgery Patients

By John Commins

Morbidly obese patients who lose 20 pounds before knee replacement surgery cut their hospital stays by about one day, and were 76% less likely to have an extended hospital stay of four days or longer, new research shows.

Writing in The Journal of Bone & Joint Surgery, researchers at Dartmouth-Hitchcock Medical Center said shorter hospital stays were not associated with morbidly obese patients who lost between five and 10 pounds before the surgical procedure.

“Losing at least 20 pounds was associated with lower absolute length of stay, lower odds of extended length of stay, and lower odds of being discharged to a facility,” lead researcher David S. Jevsevar, MD, MBA, and colleagues wrote.

The study reviewed data on 203 morbidly obese patients who underwent total knee arthroplasty between 2011 and 2016 at one hospital. These patients accounted for 13.5% of the 1,500 patients who had knee replacement in that span.

In the months before surgery, 41% of patients lost at least five pounds, 29% lost at least 10 pounds, and 14% lost at least 20 pounds.

The researchers found that patients who lost at least 20 pounds spent about one fewer day in the hospital and were 76% less likely to have an extended hospital stay of four days or longer. Weight loss of at least 20 pounds was also associated with a 72% reduction in the odds of being discharged from the hospital to a facility.

However, no noticeable improvements in outcomes were noted for patients who lost between five and 10 pounds, and the study found that length of hospital stay and operative time were “significantly increased” for patients who added weight before surgery.

In addition, no association was found between preoperative weight loss and change in operative time or with postoperative health improvements and functions.

Jevsevar said larger studies will be needed to prove that preoperative weight loss can improve outcomes after total knee replacement. However, he said the Dartmouth-Hitchcock study suggests that “providers may want to focus on larger, specific amounts of weight loss in morbidly obese patients preparing for total knee arthroplasty.”

John Commins is a content specialist and online news editor for HealthLeaders, a Simplify Compliance brand.