Comparison study of patient demographics and risk factors for infections following primary total elbow arthroplasty

Abstract

BackgroundInfections are a feared complication following primary total elbow arthroplasty (TEA). Studies comparing baseline demographic profiles and identifying risk factors associated with developing surgical site infections (SSIs) or peri-prosthetic joint infections (PJIs), following primary TEA are limited. This study was therefore aimed to: (1) compare patient demographics; and (2) identify patient-related risk factors for the development of infections following a primary TEA. MethodsPatients who underwent primary TEA from January 1, 2005 to March 31, 2014 were identified in an administrative claims database. The study group consisted of all patients who developed either SSIs within 90-days or PJIs within 2-years following the index procedure, respectively. A total of 23,134 primary TEAs were identified between 2005 and 2014, of which 757 (3.3%) were coded as being infected. Primary outcomes that were assessed included comparing baseline patient demographics and identifying patient-related risk factors for developing PJIs. Pearson's chi-square analyses were used to compare study group demographics to their counterparts. Welch's t-test was used to compare mean Elixhauser-Comorbidity Index scores between the cohorts. Multivariate binomial logistics regression was used to calculate odds-ratios (OR) for patient-related risk factors. A P value less than .05 was considered statistically significant. ResultsPatients who developed infections were significantly different compared to their counterparts with respect to the variables analyzed. Patients developing infections were found to have a higher prevalence of comorbidities as measured by mean Elixhauser-Comorbidity Index scores in patients who developed SSIs (7 vs. 5, P < .0001) or PJIs (7 vs. 5, P < .0001) compared to their respective counterparts. The greatest risk factors for SSIs within 90-days following primary TEA were rheumatoid arthritis (OR: 1.80, P < .0001), being male (OR: 1.53, P = .009), and depressive disorders (OR: 1.52, P = .004), whereas iron deficiency anemia (OR: 2.04, P < .0001), rheumatoid arthritis (OR: 1.78, P < .0001), and pathologic weight loss (OR: 1.73, P < .0001) were associated with an increased odd of PJIs. ConclusionThis study demonstrated statistically significant differences between patients who developed and did not develop infections following primary TEA and identified a myriad of risk factors associated with these adverse events. The results from this study can help identify high risk patients by orthopedic surgeon in order to potentially mitigate the incidence of either SSIs or PJIs in patients undergoing TEA. Level of EvidenceLevel III; Database Study, Retrospective Case-Control Prognosis Study