Gout and healthcare utilization and complications after hip arthroplasty: a cohort study using the US National Inpatient Sample (NIS)

Total Hip Arthroplasty Outcomes in Patients with Gout: A Retrospective Analysis of Matched Large Cohorts

Background

Gout is the most prevalent form of inflammatory arthritis in the world. Total hip arthroplasty (THA) has emerged as a widely sought-after and highly effective surgical procedure for advanced hip diseases. However, there is a lack of research on the impact of gout on primary THA outcomes in large cohorts. This study aimed to address this gap by primarily investigating complications following THA in patients with or without gout.

Methods

Patients with records of gout in the 2 years leading up to their primary THA and who also have at least 2 years of follow-up were identified using a national insurance database and compared to a 5:1 matched control. A total of 32,466 patients with gout and 161,514 patients without gout undergoing THA were identified. Multivariable logistic regression analyses were done for medical complications up to 90 days and surgical complications up to 2 years. In addition, 90-day emergency department (ED) visits and inpatient readmission were also documented.

Results

Patients with gout demonstrated higher rates of medical complications including deep vein thrombosis, transfusion, acute kidney injury, and urinary tract infection than non-gout patients (p < 0.001). Gout patients also showed higher rates of pulmonary embolism (p = 0.017). Increased incidences of surgical complications were identified in gout patients, specifically wound complications and periprosthetic joint infection (p < 0.001). There was an increased risk of revision for gout patients up to 90 days (p = 0.003), 1 year (p = 0.027), and 2 years (p = 0.039). There was also an increased risk of dislocation for gout patients up to 90 days (p = 0.022) and 1 year (p = 0.047), but not at 2 years. No significant difference was observed in aseptic loosening or periprosthetic fracture. Additionally, gout patients also demonstrated a higher likelihood of 90-day ED visits and readmission (p < 0.001).

Conclusions

Primary THA in gout patients is associated with increased risks of multiple medical and surgical complications. Our findings provide insights into the planning and expectation of THA for patients with gout. These insights have the potential to benefit the decision-making process for gout patients considering THA.

Total hip arthroplasty complications in patients with chronic kidney disease: A comparison study

Background

It has been noted in the literature that there are increased complication rates following total hip arthroplasty (THA) in patients with chronic kidney disease (CKD) or end stage renal disease (ESRD). However, there is little data directly comparing outcomes in patients undergoing THA for osteoarthritis (OA) versus ESRD or CKD with OA. The objective of this study is to illustrate the risk of developing postoperative complications after THA in the CKD and ESRD populations by stage of disease when compared to a control group (OA) and thus better equip orthopaedic providers in the care of these patients.

Methods

The National Inpatient Sample (NIS) was utilized to identify patients undergoing elective THA from 2006 to 2015 with OA, ESRD, and CKD. The prevalence of preoperative comorbidities and the incidence of numerous postoperative complications broken into categories were examined.

Results

Between 2006 and 2015 the NIS database reported 4,350,961 patients diagnosed with OA, 8355 diagnosed with ESRD, and 104,313 diagnosed with CKD undergoing THA. The incidence of wound hematoma (2.5% vs. 0.8%; p < .0001), wound infection (0.7% vs. 0.4%; p = .0319), cardiac (1.3% vs. 0.6%; p = .0067), urinary (3.9% vs. 2.0%; p < .0001), and pulmonary complications (2.2% vs. 0.5%; p < .0001) occurred more frequently in patients with OA and ESRD when compared to only OA patients. For patients with OA and CKD, stages 3-5 saw at least half of the complication categories occur at significantly higher rates than OA patients.

Conclusion

This study shows that patients with ESRD and CKD have increased rates of complications after THA. This study's specific breakdown by stage and complication can benefit orthopaedic surgeons and practitioners in realistic pre and postoperative planning and provides data that could benefit decision making on bundled reimbursement for this specific patient population, as providers could better account for the postoperative complications noted above and their associated costs.

Orthopaedic Management of Gout

Gout is characterized by the deposition of monosodium urate crystals in patients with chronically elevated blood levels of uric acid. It is the most common form of inflammatory arthritis in the United States and is often comorbid with hypertension, obesity, and chronic kidney disease. Initial presentation is usually an acutely warm, swollen joint, most commonly the first metatarsophalangeal joint, but a variety of locations may be affected. The main treatment for gout is medical management of acute inflammation and chronic uric acid levels, but surgical treatment may be indicated in cases of damage to the surrounding soft tissue, concomitant septic arthritis, symptomatic cartilage loss, or neurologic deficits. Based on the literature to date, gout does not seem to independently affect outcomes after total hip, knee, and ankle arthroplasty, but associated comorbidities affecting outcomes in these patients should be considered.