Costs and length of stay for patients with and without sickle cell disease after hysterectomy, appendectomy, or knee replacement

SCD is the most commonly inherited hemoglobinopathy, characterized by anemia and unpredictable, acute complications that can rapidly become life-threatening [9–14]. SCD affects more than 70,000 people in the United States and is predominant in African Americans, occurring in approximately 1 out of every 500 African American births [9,15]. Compared to patients without SCD, patients with SCD who undergo surgical procedures are at greater risk for preoperative and postoperative complications, with SCD-related postoperative complications occurring in over 30% of patients, even after preoperative blood transfusion [5–7, 16]. In a health care environment increasingly moving toward differentiated payments for lower- and higher- quality care, it is important to understand patient and procedural factors that contribute to higher complication rates, longer stays, and higher costs. We recently performed an analysis comparing inpatient outcomes between patients with and without SCD who underwent the 2 most commonly performed nonobstetric surgical procedures among patients with SCD in the United States: cholecystectomy and hip replacement [8]. The study revealed that patients with SCD who underwent either procedure incurred longer inpatient stays and higher inpatient costs than patients without SCD. In the present study, we expanded our analysis to other less commonly performed procedures (ie, hysterectomy, appendectomy, and knee replacement) in patients with SCD and found similar results. Using the 2002–2006 Nationwide Inpatient Sample (NIS) from the Healthcare Cost and Utilization Project (HCUP), we identified 118 SCD and 85,073 non-SCD discharges for hysterectomy, 69 SCD and 24,802 non-SCD discharges for appendectomy, and 62 SCD and 14,517 non-SCD discharges for knee replacement. For each procedure, patients with SCD were younger than patients without SCD (Table; P < 0.001 for each comparison). Hysterectomy and knee replacement were less likely to be recorded as elective surgery for patients with SCD than for patients without SCD (79.7% vs 86.0% [P = 0.05] for hysterectomy; 77.4% vs 93.1% [P < 0.001] for knee replacement). Compared to patients without SCD, patients with SCD were significantly more likely to receive blood transfusions during the inpatient stay (28.0% vs 4.3% [P < 0.001] for hysterectomy; 18.8% vs 2.5% [P < 0.001] for appendectomy; 30.6% vs 17.5% [P = 0.007] for knee replacement). Unadjusted comparisons of length of stay revealed that patients with SCD had mean hospital stays that were approximately 2 times longer than for patients without SCD who underwent the same procedure (P < 0.001 for each comparison). Mean inpatient costs followed a similar pattern, ranging from 32% higher for knee replacement to 91% higher for appendectomy (P < 0.001 for each comparison). The average cost among patients with SCD who underwent appendectomy was nearly $10,000 more than for patients without SCD. Percentages of patients with SCD who died after appendectomy or knee replacement were also significantly higher than for patients without SCD who underwent the same procedure (P = 0.02 for appendectomy; P = 0.001 for knee replacement), but the absolute numbers of patients with SCD who died were small (n ≤ 10 for each procedure). Table Characteristics and Outcomes of Patients With or Without Sickle Cell Disease Who Underwent Hysterectomy, Appendectomy, or Knee Replacement After adjustment for patient, procedural, and hospital characteristics, length of stay and inpatient cost estimates remained significantly higher for patients with SCD than for patients without SCD (P < 0.001 for each comparison). Compared to patients without SCD, the adjusted length of stay for patients with SCD was 35% longer for hysterectomy (length of stay ratio, 1.35; 95% confidence interval [CI], 1.23–1.49), 85% longer for appendectomy (length of stay ratio, 1.85; 95% CI, 1.56–2.20), and 81% longer for knee replacement (length of stay ratio, 1.81; 95% CI, 1.62–2.02). Compared to patients without SCD, the adjusted cost estimates for patients with SCD were 28% higher for hysterectomy (cost ratio, 1.28; 95% CI, 1.18–1.39), 61% higher for appendectomy (cost ratio, 1.61; 95% CI, 1.40–1.85), and 19% higher for knee replacement (cost ratio, 1.19; 95% CI, 1.08–1.32). After including inpatient length of stay and discharge disposition in the regression model for inpatient costs, we found that higher inpatient costs were largely attributable to longer hospital stays for all 3 surgical procedures. Inpatient costs for patients with SCD who underwent hysterectomy or appendectomy remained 8% and 22% higher, respectively, than for patients without SCD, after adjustment for inpatient length of stay and discharge disposition (cost ratio for hysterectomy, 1.08; 95% CI, 1.01–1.15; cost ratio for appendectomy, 1.22; 95% CI, 1.11–1.33). Among patients with SCD, sickle cell crisis occurred in 31.9% (22/69) of patients who underwent appendectomy. In patients who underwent hysterectomy or knee replacement, ≤ 10 patients in each group experienced sickle cell crisis. Due to the small number of patients with sickle cell crisis, we did not evaluate the impact of this complication on length of stay, costs, or mortality. In summary, after adjustment for patient, procedural, and hospital characteristics, patients with SCD incurred significantly longer inpatient stays and higher total costs for hysterectomy, appendectomy, and knee replacement than patients without SCD. Patients with SCD who underwent hysterectomy, appendectomy, or knee replacement were also significantly more likely to have a procedure code for blood transfusion during the inpatient stay, though the overall rates may be somewhat low due to undercoding of this procedure [17]. After accounting for inpatient length of stay and discharge disposition, the impact of SCD on inpatient costs was attenuated for all 3 surgeries, but costs remained significantly higher for appendectomy and hysterectomy. The higher costs for appendectomy and hysterectomy may be associated with higher rates of sickle cell crisis and nonelective admissions for these 2 procedures. The study results were consistent with previous findings that focused on cholecystectomy and hip replacement [8], indicating that the study results may be generalizable to other procedures.