The prevalence of malnutrition in patients requiring total joint arthroplasty in a South African tertiary hospital

Abstract

Background: With the global increase in total joint arthroplasty (TJA), including total hip arthroplasty (THA) and total knee arthroplasty (TKA), there has been a parallel increase in complications. Optimising modifiable risk factors preoperatively can limit the impact of postoperative complications. Malnutrition is one such modifiable risk factor. With limited evidence regarding malnutrition in patients undergoing TJA in South Africa, we sought to determine the prevalence of malnutrition in patients presenting for TJA at a single institution in South Africa. The objectives of the study were to determine the prevalence of malnutrition among patients presenting to a South African tertiary institution for TJA, and to determine the relationship between malnutrition and comorbidities and demographics.

Methods: We performed a retrospective review of 414 patients presenting for the first time to an arthroplasty unit over a 15-month period. Patients presenting for primary TJA, revision TJA, and patients presenting for fractured neck of femur (FNF) were included. Serological testing of albumin < 35 g/L and/or low transferrin (< 2 g/L) were used to diagnose malnutrition. The relationship between demographic data, comorbidities, presentation for type of TJA, and malnutrition were evaluated.

Results: In total, 414 patients were included. The mean age was 61.1 ± 10.95 years, and 75% (n = 311) were female. Patients presenting for elective TJA composed 88% (n = 366) of the study population, with 12% (n = 48) patients referred for FNF. The mean BMI was 33.3 ± 8.15 kg/m². The prevalence of malnutrition was 11% (n = 47). Patients presenting for elective TJA had a prevalence of malnutrition of 6% (n = 23), compared to patients presenting with FNF of 50% (n = 24). Hypertension (45%, n = 18), HIV (19%, n = 9), diabetes mellitus (18%, n = 7), chronic kidney disease (18%, n = 7) and inflammatory arthritis (15%, n = 6) were the most common comorbidities in patients with malnutrition. Patients with malnutrition had a higher mean age (p = 0.024), lower mean haemoglobin (p < 0.001), lower mean BMI (p = 0.047) and a lower CD4 in HIV-positive patients (p = 0.031).

Conclusion: The prevalence of malnutrition of 11% in this cohort of South African patients presenting for TJA is similar to published results from developed countries. There is a need for high-powered prospective studies to determine the viability of routine preoperative nutritional testing or limit testing of high-risk patients.

Level of evidence: Level 4