Effects of malnutrition on outcomes of patients with femoral head osteonecrosis undergoing total hip arthroplasty: A population-based study.

Background: This study aimed to evaluate the impact of malnutrition on in-hospital outcomes in patients undergoing total hip arthroplasty (THA) for osteonecrosis of the femoral head (ONFH).

Methods: This population-based retrospective study extracted data of patients undergoing THA for ONFH in the US National Inpatient Sample between 2005 and 2018. Factors associated with in-hospital mortality, medical and surgical complications, unfavorable discharge, and prolonged hospital stay were determined by logistic regression analysis.

Results: A total of 72,304 adults ≥18 years old with nontraumatic ONFH admitted for primary THA were included. Malnutrition was detected in 7152 (9.9%) patients using validated discharge codes. In-hospital mortality was 0.8% vs 0.1% for patients who were malnourished vs nonmalnourished. After adjusting for confounders, malnutrition was significantly associated with an increased risk of in-hospital death (adjusted odds ratio [aOR], 4.67; 95% CI, 2.43-8.97), medical complications (aOR, 1.49; 95% CI, 1.32-1.68), surgical complications (aOR, 1.78; 95% CI, 1.61-1.96), unfavorable discharge (aOR, 1.24; 95% CI, 1.11-1.39), and prolonged hospital stay (aOR, 1.90; 95% CI, 1.67-2.16) compared with adequate nutrition. Malnutrition was also associated with higher total hospital costs (adjusted β = $9620; 95% CI, 7.87-11.36). Furthermore, the association between malnutrition, any medical or surgical complications, and unfavorable discharge was stronger in patients younger than 50 years than those ≥50 years old.

Conclusions: In US patients undergoing primary THA for ONFH, malnutrition increases the risk of unfavorable in-hospital outcomes. This patient subgroup may require special attention and better strategies to improve perioperative care.