Hip Fracture Admissions Among Medicare Beneficiaries 2010-2015 -Rising Hospital Costs and Falling Reimbursements

Abstract

Background: This paper reports trends in care and costs associated with hip fracture admissions among Medicare Beneficiaries (MB). Methods: This retrospective study identified 1,558,428 primary hip fracture admissions using the Medicare Provider Analysis and Review Files from fiscal years 2010 through fiscal year 2015. Results: The total number of admissions rose from 246,825 to 276,659; however, rate per 1000 MB was 4.96 in 2010 and 4.98 in 2015. In all years, the patients were mostly female, Caucasian, and over age 80. Patient complexity increased as evidenced by greater comorbidity reporting. Most patients received an Open Reduction and Internal Fixation (ORIF) or partial hip arthroplasty, although there was a slight decline in partial hip arthroplasty and concurrent rise in total hip replacement. The cost per patient rose from $12,363 to $14093 (p<0.0001) despite a fall in average LOS from 5.8 to 5.42 days (p<0.0001) and a fall in in-hospital mortality from 2.6% to 2.2%. Reimbursements fell $1,118 from $10,304 in 2010 to $9,186 in 2015. Conclusions: Average hospital cost per beneficiary rose during our study period while inflation-adjusted reimbursements fell. We found lower average LOS and postop mortality. Rates of AKI on presentation and co-morbid infection have risen. The number of patients receiving THA has risen but the most common treatment is femur repair. Background On July 25, 2016, the Department of Health & Human Services (HHS) proposed a new model that expands bundled payments to include Surgical Hip and Femur Fracture Treatment (SHFFT) [1-2]. This progression theoretically shifts Medicare payments from quantity to quality by creating strong incentives for hospitals to deliver better care at a lower cost [3-4]. An estimated 300,000 Medicare beneficiaries suffer a hip fracture per year [5]. In 2014, an average of 5.8 beneficiaries per 1,000 suffered a hip fracture [6]. The primary objective of this study is to report on trends associated with MBs admitted to US hospitals with a primary diagnosis of hip fracture from fiscal years 2010 through fiscal year 2015. We report outcomes among patients receiving Total Hip Arthroplasty (THA), Partial Hip Arthroplasty (PH), femur repair, and non-operative care. We predicted higher prevalence of baseline comorbidities, higher costs, and lower reimbursements due to national policies favoring cost settings in the setting of an increasingly older US population. Citation: Sundaram K, Culler S, Simon A, Jevsevar DS, Gitajn IL, et al. (2018) Hip Fracture Admissions among Medicare Beneficiaries 2010-2015-Rising hospital costs and falling reimbursements. Int J Musculoskelet Disord: IJMD-107 DOI: 10.29011/ IJMD-107. 000007 2 Volume 2018; Issue 02 Methods Data Source Center for Medicare and Medicaid Services maintains a database called Med PAR that contains all submitted claims for services provided to MBs. We obtained a data set from this database that spanned from 2010 to 2015. Study Population Selection 100% of Medicare Part A and C claims were included. During the study period CMS required claims for every hospitalization ensuring there were no missing claims from part C. Individuals under age 65 may be eligible for Medicare due to disabilities. After careful consideration, we decided to include this population based on prior literature that demonstrated that most patients 40-50 years share a common mechanism with patients over 65-osteoporotic fragility fractures with a fall as an inciting event [7]. Furthermore, prior work from the Kaiser-Family foundation found that a similar proportion of MBs under-65 versus over-65 have 5 or more medical conditions (31% versus 28% percent) suggesting a similar burden of comorbid disease [8]. Patients under 65 eligible for Medicare due to end-stage renal disease were included due to constraints of our data set but prior research suggests they constitute less than 1% of the total Medicare Population [9-10]. The Med Par dataset includes basic demographic information, up to 25 diagnostic ICD-9-CM codes with Present on Admission (POA) flags, primary procedure code, up to 24 additional ICD-9CM procedures codes, LOS in days, discharge status (discharge disposition or site), total charges, and total reimbursement from the Medicare program. We identified patients using ICD-9 codes after careful consideration of prior literature. Data support the use of “fracture of the neck of Femur” relative to chart review (PPV=0.85-0.93) [11-14]. While “pathological fractures” most commonly refer to osteoporotic fragility fractures some clinicians may use the code for patients with metastatic disease. Prior studies have shown a very low rate of metastasis related oncologic fracture in the Medicare population (0.3 patients per 1,000 MB) and the risk of false negatives when excluding “pathologic fracture”, we elected to use ICD-9 code 733.14 for pathological fracture of the neck of the femur [15-16]. Codes of for atypical femur fractures had low sensitivity for extra-capsular fractures and rates of midshaft and distal femur fractures are low in an elderly population, so we included the ICD-9 code for pathological fracture of other specified part of the femur. Ultimately we searched for patients who had any of the following 3 codes in any of the diagnostic positions in the database. Fracture of the neck of Femur (ICD-9 Code 820) • Pathologic fracture of neck of femur (ICD-9 code 733.14) • Pathologic fracture of other specified part of femur (ICD-9 • 733.15) A total of 1,558,428 Medicare beneficiaries were in the final study population. The observation period for diagnoses for each patient began on admission and ended on discharge. Operational Definitions and Analysis Medicare Reimbursement Was defined strictly as the Medicare payment for each hospitalization. This does not include any out-of-pocket payments by MBs or secondary payers. The cost of each hospitalization was estimated by multiplying total billed charges by the hospital-level cost-to-charge ratio obtained from the appropriate hospital’s Annual Medicare Cost Report (or the most recent settled cost report of the hospital). Length-of-Stay (LOS) was defined as the whole number of days from admission to discharge. Our treatment groups included total-hip arthroplasty (THA), Partial Hip Arthroplasty (PHA), femur repair, and non-operative treatment. Claims were evaluated using both Part A and Part C. Statistical Analysis A two sided chi-square test assessed the presence or absence statistically of significant univariate trends over the study period. Subsequent one-sided analyses tested the presence or absence of a trend with a positively skewed tail or a negatively skewed tail. Trends were statistically different if the P value was less than or equal to 0.01. Organizational variables analyzed include estimated hospital costs, Medicare reimbursements, length of stay, and discharge status. Clinical variables included type of operative treatment, adverse events, and mortality. All analyses were performed with SAS 9.3 (SAS Institute, Cary, North Carolina). Approval and Funding Our study received evaluation and approval from the Dartmouth-Hitchcock IRB as an exempt study. Funding did not play a role in our study. Results The final study population included a total of 1,558,428 Medicare beneficiaries over 6 years. (Figure 1) describes the number of beneficiaries treated by year. The total number of MBs experiencing a primary hip fracture has increased from 246,825 in FY-2010 to 276,659 in FY-2015. (Figure 1), Compounded Annual Growth Rate=2.8%). The rate of fractures per 1000 MB was 4.96 in 2010 versus 4.98 in 2015. (Figure 2) Citation: Sundaram K, Culler S, Simon A, Jevsevar DS, Gitajn IL, et al. (2018) Hip Fracture Admissions among Medicare Beneficiaries 2010-2015-Rising hospital costs and falling reimbursements. Int J Musculoskelet Disord: IJMD-107 DOI: 10.29011/ IJMD-107. 000007 3 Volume 2018; Issue 02 Figure 1: Absolute Annual Rate of Hip Fractures among Medicare Beneficiaries. Figure 2: Annual Rate of Hip Fractures per 1,000 Medicare Beneficiaries. In 2015, women constituted 70.5% of our population. 64.2% of patients had reached age 80 or greater and Caucasians represented 91.4% of the population. Each of these variables experienced a statistically significant fall (p≤0.001, Table 1); however, none of the listed demographic changes declined by more than 2%. Variable 2010a 2011a 2012a 2013a 2014a 2015a p-Valueb