Factors associated with total shoulder arthroplasty cost variation in the state of Utah

Abstract

Hypothesis and BackgroundThe shoulder is the third most commonly replaced joint in the United States. Access to high-volume surgeons has increased in recent years, and overall utilization of total shoulder arthroplasty (TSA) is increasing in the Medicare population across the country. TSA is thus becoming a significant source of cost nationally. The purpose of this study included (1) identifying regional cost variations for patients undergoing TSA and (2) assessing factors contributing to higher cost after TSA. MethodsUtah’s All-Payer Claims Database was queried from 2013 through 2016. Patients undergoing TSA were identified using Current Procedural Terminology codes, and those who were continuously enrolled (12 months preoperatively and 12 months postoperatively) were included. The total cost was the primary outcome and the sum of medical cost (inpatient, outpatient, office, and emergency room visits, surgical costs, lab tests) and pharmacy cost. Inflation was adjusted, and costs were expressed in 2016 dollars. Baseline covariates were collected. Generalized linear regression with gamma distribution and log link function was used to identify baseline factors significantly associated with the outcomes. ResultsOf the 1609 included patients, the mean (±standard deviation) age was 68 (±11) years, and 49% were male. The majority were White (89%), and 92% lived in urban locations. One year after the index surgery, the mean pharmacy cost was $7,612, the mean medical cost was $61,433, and the mean total cost was $69,046. Older subjects (coefficient [B] = 0.13, P ≤ .01), male sex (B = 1.38, P ≤ .01), those who lived in urban areas (B = 2.09, P < .01), and those with depression (B = 1.08, P = .03) had higher health-care costs following TSA. Patients in the top 30% of the study population for perioperative cost were significantly more likely to be younger (odds ratio [OR]: 0.95, P = .00), live in an urban environment (OR: 1.98, P = .03), have asthma/chronic obstructive pulmonary disease (OR: 1.85, P = .00), congestive heart disease (OR: 1.58, P = .02), and a higher Elixhauser Comorbidity Index score (OR: 1.09, P = .05). Patients in the top 30% of the population for perioperative cost experienced significantly more complications (P < .01). Discussion and ConclusionThe total cost of TSA 1 year after the index surgery is $69,046, with medical cost being the largest contributor. Male sex, increased age, depression, and urban areas were all significantly associated with higher costs following TSA after accounting for preoperative costs. Patients in the top 30% of the population for perioperative cost were significantly more likely to be young, live in an urban environment, and have asthma/chronic obstructive pulmonary disease , congestive heart disease , or a higher Elixhauser Comorbidity Index score. They also experienced significantly more complications.