More than 250,000 hip fractures occur annu­ally in the United States, and the incidence is expected to increase among the elderly as society continues to outlive previous generations. Hip fractures have a significant impact on health-related quality of life and are a major source of healthcare expenditures, and almost all result in hospitalization and surgery. They also often result in nursing home admission, long-term dis­ability, and extended periods of rehabilitation. Patients with hip fractures frequently present with comorbid illnesses, including many chronic diseases. “In addition to increasing resource uti­lization, the presence of several comorbidities has been identified as a strong preoperative risk factor for death in patients with hip fractures,” says Kevin P. Black, MD.

A New Large-Scale Analysis of Hip Fracture

Previous research has examined comorbidities and hospitalization costs for hip fracture in the elderly, but these studies have been conducted on a small scale. In the January 4, 2012 Journal of Bone and Joint Surgery, Dr. Black and colleagues had a larger-scale study published that aimed to gain a better understanding of the coexist­ing medical conditions that impact the cost of treating patients with hip fractures. “A better understanding of the impact of comorbidities on inpatient costs and length of stay may advance the discussion on appropriate reimbursement for patients with hip fractures and multiple comor­bidities,” says Dr. Black. “It may also lead us to the development of strategies to better manage comorbidities in this patient population.”

Hospital discharge information was gathered from an AHRQ report that included data from more than 1,000 hospitals in 40 states. For the more than 32,000 patients involved in the study, information was provided on race, sex, hospital­ization cost, length of stay, age, type of hip frac­ture sustained, and type of surgical hip fracture treatment. Patients in the study most commonly had two or three comorbidities (Figure 1). Less than 5% of patients in the study had no comor­bidities (Figure 2). Hypertension was the most common comorbidity identified (67%), but other common conditions included:

Deficiency anemias.
Fluid and electrolyte disorders.
Chronic lung diseases.
Uncomplicated diabetes.
Neurologic disorders.
Congestive heart failure.

“Comorbidities appeared to significantly raise costs of hospitalization and length of hospi­tal stay,” Dr. Black says. “The treatment of hip fractures was largely affected by specific comor­bidities, which also played a role in increasing costs and length of stay.” Hip fracture patients who were malnourished experienced the greatest increase in costs, followed by those with pulmo­nary circulatory disorders. Recent weight loss or malnutrition increased hospitalization stays by an average of 2.5 days. Congestive heart failure, pulmonary circulation disorders, fluid and elec­trolyte disorders, paralysis, and blood clot disor­ders also increased hospitalizations significantly.

Important Implications of Comorbidities & Hip Fractures

According to Dr. Black, the results of his study team’s analysis may have major implications for physicians, hospitals, and payors. “Currently, reimbursement to hospitals for internal fixa­tion of hip fracture only considers if patients are categorized as having a major comorbidity, a comorbidity, or no comorbidity,” he says. “Reim­bursement for hemiarthroplasty involves catego­rizing patients as either having a major comorbid condition or not. Even if patients have multiple major comorbid conditions, reimbursement only accounts for a single, unspecified comorbid­ity and does not account for increased use of resources. Accounting methods in the current reimbursement system may not adequately reflect the financial burden of the most medically com­plex patients with hip fractures. More research is needed so that hospitals and providers are appro­priately reimbursed when managing patients with hip fractures and multiple comorbid conditions.”

Further investigation is warranted to better understand the total cost of caring for hip fracture patients and to analyze the quality or outcomes of care. “Our study focused only on acute hospitalization, but care typically extends beyond that,” says Dr. Black. “Many patients are discharged to rehabilitation and skilled nursing facilities, which can increase costs substantially. In addition, it’s important to gain a better under­standing of the comorbidities that affect hip frac­ture patients. In doing so, we hope to determine if addressing these comorbidities can improve outcomes and allow us to improve quality and safety of care.”

Fall prevention efforts are another important component to consider. “As our population ages, the number of hip fractures will increase,” Dr. Black says. “When older patients suffer their first fragility fracture, their risk for future frac­tures increases significantly. Physicians need to increase efforts to screen patients for fracture risk and provide education to patients to prevent fractures from occurring. These efforts can go a long way toward curbing long-term problems for older patients.”


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