Malnutrition affects infection rates and quality of life in patients undergoing primary hip and knee arthroplasty: a retrospective study

<b>Background</b>: Although malnutrition is globally associated with incremental morbidity, mortality, and cost, there has been a fundamental lack of consensus on diagnostic criteria for application in clinical settings. The study aims were (i) to identify the role of malnutrition as an independent risk factor for complications in the total joint arthroplasty (TJA) context; and (ii) to analyse the impact of malnutrition on treatment success, specifically in terms of patient-reported quality of life. <b>Methods</b>: The study retrospectively analysed 1070 patients undergoing total hip or knee arthroplasty between January 2019 and July 2022. Before the surgery, patients' nutritional status were assessed through Nutritional Risk Screening 2002 (NRS-2002) and controlling nutritional status (CONUT) scores. Patients were classified in two different groups: patients with NRS <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mo>≥</mml:mo></mml:math> 3 were included in the Malnutrition group, and patients with NRS <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mo><</mml:mo></mml:math> 3 in the Control group. <b>Results</b>: A total number of 682 patients was included in the study. Mean age was 70.1 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mo>±</mml:mo></mml:math> 9.6, 53 % women ratio, BMI 28.1 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mo>±</mml:mo></mml:math> 4.8 kg m^-2. A univariate regression, adjusted for age and sex, was performed. Both NRS-2002 and the CONUT score were significant risk factors in infectious complications and in EQ5 domains of quality-of-life assessment ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>p</mml:mi> <mml:mo><</mml:mo> <mml:mn>0.05</mml:mn></mml:mrow> </mml:math> ). <b>Conclusions</b>: Malnutrition, as identified by both the NRS-2002 and CONUT scores, emerges as an independent risk factor, contributing to worse post-operative outcomes and increased complications, thereby decreasing the potential benefits of TJAs. Pre-operative nutritional assessment and targeted intervention to address malnutrition can play a crucial role in improving clinical outcomes, quality of life, and complication rates.