Aggregate hospital inpatient costs and stays by payer, 2013

Figure 1 presents the distribution by expected primary payer for aggregate hospital costs and total hospital inpatient stays in 2013.

Figure 1

Aggregate hospital costs and hospital stays by payer, 2013. Source: Agency for Healthcare Research and Quality (AHRQ), Center for Delivery, Organization, and Markets, Healthcare Cost and Utilization Project (HCUP), National Inpatient Sample (NIS), 2013 (more...)

• In 2013, Medicare accounted for the largest proportion of aggregate hospital costs (46 percent).
  Patients with primary Medicare coverage accounted for 46 percent of the $381.4 billion in aggregate hospital costs in 2013. Private insurance was the second most common payer, accounting for 28 percent of total costs, followed by Medicaid with 17 percent of costs. Stays of uninsured patients represented 5 percent of total hospital costs. Government payers (Medicare and Medicaid) accounted for 63 percent of all hospital costs.
  Patients covered by Medicare accounted for a larger proportion of aggregate hospital costs (46 percent) than of hospital stays (39 percent). In contrast, patients covered by Medicaid accounted for only 17 percent of hospital costs but 21 percent of hospital stays.

Most expensive conditions treated in U.S. hospitals, 2013

Table 1 presents the most expensive conditions treated in U.S. hospitals among all payers in 2013.

Table 1

The 20 most expensive conditions treated in U.S. hospitals, all payers, 2013.

• The 5 most expensive conditions accounted for 20.5 percent of aggregate hospital costs; the 20 most expensive conditions accounted for nearly half (47.7 percent) of aggregate hospital costs.
  Septicemia was the most expensive condition treated, accounting for $23.7 billion, or 6.2 percent of the aggregate costs for all hospitalizations. Other high-cost hospitalizations were for osteoarthritis ($16.5 billion, or 4.3 percent), liveborn (newborn) infants ($13.3 billion, or 3.5 percent), complication of device, implant or graft ($12.4 billion, or 3.3 percent), and acute myocardial infarction ($12.1 billion, or 3.2 percent).
  Hospital stays with principal diagnoses of complications of device, implant or graft and complications of surgical procedures or medical care accounted for 5 percent of aggregate hospital costs.
• The 20 most expensive conditions accounted for 43.7 percent of all hospital stays.
  Liveborn infants accounted for 10.6 percent of all hospital stays. Septicemia was the second most common reason for hospitalization, accounting for 3.6 percent of stays, followed by osteoarthritis (2.9 percent), pneumonia (2.7 percent), congestive heart failure (2.5 percent), and mood disorders (2.3 percent).

Most expensive conditions by primary payer, 2013

Tables 2 through 5 list the 20 most expensive conditions for stays covered by Medicare, Medicaid, and private insurance and for uninsured stays in 2013.

Table 2

The 20 most expensive conditions billed to Medicare, 2013.

Table 3

The 20 most expensive conditions billed to Medicaid, 2013.

Table 4

The 20 most expensive conditions billed to private insurance, 2013.

Table 5

The 20 most expensive conditions for uninsured individuals, 2013.

• Seven conditions were among the 20 most expensive conditions for all four payer groups.
  There were some commonalities across payers in the conditions that generated high aggregate hospital costs. For all four payer groups, septicemia ranked among the four most expensive conditions.
  The following conditions also appeared among the 20 most expensive conditions for all four payer groups:
  • Complication of device, implant or graft
  • Acute myocardial infarction
  • Congestive heart failure
  • Pneumonia
  • Acute cerebrovascular disease
  • Respiratory failure
  Several other conditions were ranked among those with the highest aggregate hospital costs across three of the four payer groups:
  • Complications of surgical procedures or medical care was top ranked for stays covered by Medicare, Medicaid, and private insurance.
  • Diabetes with complications was top ranked for hospitalizations covered by Medicare and Medicaid and those that were uninsured.
  • Coronary atherosclerosis and cardiac dysrhythmias were top ranked for stays covered by Medicare and private insurance and for uninsured stays.
  • Mood disorders, liveborn infants, and biliary tract disease were top ranked for stays covered by Medicaid and private insurance and for uninsured stays.
• Among the most expensive conditions during hospital stays for multiple payers were osteoarthritis and back problems for Medicare and private insurance, pregnancy and childbirth for Medicaid and private insurance, and skin infections for Medicaid and uninsured.
  Given payer differences in demographic mix and service coverage, certain conditions were more common for some payer groups than for others. Osteoarthritis and back problems were top ranked among hospital stays covered by Medicare and private insurance.
  Hospitalizations associated with pregnancy and childbirth accounted for 5 of the 20 most expensive conditions for hospital stays covered by Medicaid and 3 of the 20 most expensive conditions for hospital stays covered by private insurance. Skin infections were top ranked for hospital stays covered by Medicaid and for uninsured stays.
• Seven of the 20 most expensive conditions for hospital stays billed to Medicare did not appear in the top 20 for other payers.
  The following conditions were among the 20 most expensive stays for Medicare but not for other payers:
  • Hip fracture
  • Chronic obstructive pulmonary disease
  • Heart valve disorders
  • Rehabilitation care
  • Acute and unspecified renal failure
  • Urinary tract infections
  • Gastrointestinal hemorrhage
• Cardiovascular and respiratory diseases, orthopedic conditions, and conditions involving medical complications were among the 20 most expensive conditions for Medicare-covered stays.
  Nine of the 20 most expensive conditions for hospital stays billed to Medicare involved the cardiovascular or respiratory system:
  • Congestive heart failure
  • Acute myocardial infarction
  • Pneumonia
  • Coronary atherosclerosis
  • Acute cerebrovascular disease
  • Cardiac dysrhythmias
  • Respiratory failure
  • Chronic obstructive pulmonary disease
  • Heart valve disorders
  Three of the 20 most expensive conditions were orthopedic:
  • Osteoarthritis
  • Spondylosis, intervertebral disc disorders, and other back problems
  • Hip fracture
  Two of the 20 most expensive conditions involved medical complications:
  • Complication of device, implant or graft
  • Complications of surgical procedures or medical care
• Schizophrenia was the only condition not related to pregnancy and childbirth that appeared in the top 20 for Medicaid but not for any of the other three payers.
  Hospital stays billed to Medicaid with a principal diagnosis of schizophrenia and other psychotic disorders accounted for over $1.2 billion in aggregate hospital costs in 2013. Another mental health condition—mood disorders—ranked third for Medicaid-covered patients.
• Cardiovascular and respiratory diseases, conditions involving medical complications, and neonatal complications were among the 20 most expensive conditions for Medicaid-covered stays.
  Seven of the 20 most expensive conditions during hospital stays billed to Medicaid involved the cardiovascular or respiratory system:
  • Pneumonia
  • Respiratory failure
  • Acute cerebrovascular disease
  • Cardiac and circulatory congenital anomalies
  • Congestive heart failure
  • Acute myocardial infarction
  • Hypertension complicating pregnancy
  Two of the 20 most expensive conditions involved medical complications:
  • Complication of device, implant or graft
  • Complications of surgical procedures or medical care
  Neonatal complications ranked among the 20 most expensive conditions for Medicaid-covered stays:
  • Cardiac and circulatory congenital anomalies
  • Short gestation, low birth weight, and fetal growth retardation
• Conditions seen in the 20 most expensive stays for private insurance but not for any of the other three payers included maintenance chemotherapy and secondary malignancies.
  Hospital stays billed to private insurance for secondary malignancies accounted for nearly $1.2 billion in aggregate hospital costs, and maintenance chemotherapy stays accounted for over $1.1 billion in aggregate hospital costs in 2013.
• Osteoarthritis, live births, back problems, and cardiovascular and respiratory diseases were among the 20 most expensive conditions for privately insured stays.
  Osteoarthritis, live births, and back problems were the three most expensive conditions for which privately insured individuals were hospitalized.
  Seven of the 20 most expensive conditions during hospital stays billed to private insurance involved the cardiovascular or respiratory system:
  • Acute myocardial infarction
  • Coronary atherosclerosis
  • Acute cerebrovascular disease
  • Pneumonia
  • Cardiac dysrhythmias
  • Congestive heart failure
  • Respiratory failure
• Injury accounted for 3 of the 20 most expensive conditions for uninsured individuals but only 1 of the 20 most expensive conditions billed to Medicaid or private insurance.
  The following injury-related hospital stays were among the 20 most expensive for uninsured individuals in 2013:
  • Fracture of the lower limb, which also was top ranked for privately insured individuals
  • Intracranial injury, which also was top ranked for individuals covered by Medicaid
  • Crushing or internal injury
• Three of the 20 most expensive conditions for uninsured stays did not appear in the top 20 for any other payer.
  The following are noninjury-related conditions seen in the 20 most expensive conditions for uninsured stays but not for stays covered by Medicare, Medicaid, or private insurance:
  • Pancreatic disorders
  • Alcohol-related disorders
  • Appendicitis

Diagnoses, ICD-9-CM, and Clinical Classifications Software (CCS)

The principal diagnosis is that condition established after study to be chiefly responsible for the patient's admission to the hospital.

ICD-9-CM is the International Classification of Diseases, Ninth Revision, Clinical Modification, which assigns numeric codes to diagnoses. There are approximately 14,000 ICD-9-CM diagnosis codes.

CCS categorizes ICD-9-CM diagnosis codes into a manageable number of clinically meaningful categories.⁷ This clinical grouper makes it easier to quickly understand patterns of diagnoses. CCS categories identified as Other typically are not reported; these categories include miscellaneous, otherwise unclassifiable diagnoses.

Types of hospitals included in the HCUP National Inpatient Sample

The National Inpatient Sample (NIS) is based on data from community hospitals, which are defined as short-term, non-Federal, general, and other hospitals, excluding hospital units of other institutions (e.g., prisons). The NIS includes obstetrics and gynecology, otolaryngology, orthopedic, cancer, pediatric, public, and academic medical hospitals. Excluded are long-term care facilities such as rehabilitation, psychiatric, and alcoholism and chemical dependency hospitals. Beginning in 2012, long-term acute care hospitals are also excluded. However, if a patient received long-term care, rehabilitation, or treatment for a psychiatric or chemical dependency condition in a community hospital, the discharge record for that stay will be included in the NIS.

Unit of analysis

The unit of analysis is the hospital discharge (i.e., the hospital stay), not a person or patient. This means that a person who is admitted to the hospital multiple times in 1 year will be counted each time as a separate discharge from the hospital.

Costs and charges

Total hospital charges were converted to costs using HCUP Cost-to-Charge Ratios based on hospital accounting reports from the Centers for Medicare & Medicaid Services (CMS).⁸ Costs reflect the actual expenses incurred in the production of hospital services, such as wages, supplies, and utility costs; charges represent the amount a hospital billed for the case. For each hospital, a hospital-wide cost-to-charge ratio is used. Hospital charges reflect the amount the hospital billed for the entire hospital stay and do not include professional (physician) fees. For the purposes of this Statistical Brief, aggregate costs are reported to the nearest million.

How HCUP estimates of costs differ from National Health Expenditure Accounts

There are a number of differences between the costs cited in this Statistical Brief and spending as measured in the National Health Expenditure Accounts (NHEA), which are produced annually by CMS.⁹ The largest source of difference comes from the HCUP coverage of inpatient treatment only in contrast to the NHEA inclusion of outpatient costs associated with emergency departments and other hospital-based outpatient clinics and departments as well. The outpatient portion of hospitals' activities has been growing steadily and may exceed half of all hospital revenue in recent years. On the basis of the American Hospital Association Annual Survey, 2012 outpatient gross revenues (or charges) were about 44 percent of total hospital gross revenues.¹⁰

Smaller sources of differences come from the inclusion in the NHEA of hospitals that are excluded from HCUP. These include Federal hospitals (Department of Defense, Veterans Administration, Indian Health Services, and Department of Justice [prison] hospitals) as well as psychiatric, substance abuse, and long-term care hospitals. A third source of difference lies in the HCUP reliance on billed charges from hospitals to payers, adjusted to provide estimates of costs using hospital-wide cost-to-charge ratios, in contrast to the NHEA measurement of spending or revenue. HCUP costs estimate the amount of money required to produce hospital services, including expenses for wages, salaries, and benefits paid to staff as well as utilities, maintenance, and other similar expenses required to run a hospital. NHEA spending or revenue measures the amount of income received by the hospital for treatment and other services provided, including payments by insurers, patients, or government programs. The difference between revenues and costs include profit for for-profit hospitals or surpluses for nonprofit hospitals.

Payer

Payer is the expected payer for the hospital stay. To make coding uniform across all HCUP data sources, payer combines detailed categories into general groups:

• Medicare: includes patients covered by fee-for-service and managed care Medicare
• Medicaid: includes patients covered by fee-for-service and managed care Medicaid
• Private Insurance: includes Blue Cross, commercial carriers, and private health maintenance organizations (HMOs) and preferred provider organizations (PPOs)
• Uninsured: includes an insurance status of self-pay and no charge
• Other: includes Workers' Compensation, TRICARE/CHAMPUS, CHAMPVA, Title V, and other government programs.

Hospital stays billed to the State Children's Health Insurance Program (SCHIP) may be classified as Medicaid, Private Insurance, or Other, depending on the structure of the State program. Because most State data do not identify patients in SCHIP specifically, it is not possible to present this information separately.

For this Statistical Brief, when more than one payer is listed for a hospital discharge, the first-listed payer is used.