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Part II. Detailed Statistics by Health Condition

Chronic Conditions

Diabetes: Uncontrolled Diabetes Without Complications, Short-Term Complications, Long-term Complications, and Diabetes-Related Lower Extremity Amputations


More than 18 million Americans (6 percent of the population) have diabetes, though experts estimate that nearly 30 percent of this population remains undiagnosed. The number of people diagnosed with this condition is expected to increase 44 percent by 2020. Among those at highest risk are older Americans: the number of diagnosed patients among this population is expected to increase 56 percent within this same time period.2 The increase in diabetes has been linked to a number of other factors, including the rise in obesity in the United States observed within the last 2 decades.3-5

The costs of treating this chronic disease are tremendous. The American Diabetes Association estimates that the total national cost of diabetes was $132 billion in 2002; of this figure, nearly $92 billion was spent on direct medical costs, and $40 billion went toward indirect costs related to disability, work loss, and premature mortality.6

The Institute of Medicine has identified this disease as a priority area for improvement of health care quality.7 Providing high quality care for diabetes management and treatment engages the health care system at all levels. Providers need to ensure that patients are properly diagnosed, educated, and treated. Furthermore, individuals with diabetes need to proactively manage their disease and work toward preventing secondary complications.

Timely diagnosis, effective ambulatory care, and appropriate disease management may reduce the need for hospital admissions for diabetes. Healthy People 2010, a report issued by the U.S. Department of Health and Human Services, established a target hospitalization rate of 54 per 100,000 population for persons 18-64 years of age with uncontrolled diabetes.8 This goal applies to individuals treated for uncontrolled diabetes with and without short-term complications.

  • Hospitalization rates for uncontrolled diabetes without complications dropped by nearly 30 percent between 1994 and 2000, while rates for short-term complications increased by 9 percent.
  • The West has the lowest rates of hospitalization across all 4 diabetes-related indicators. Geographic variation is greatest for treatment of uncontrolled diabetes without complications; for this condition, admissions vary by more than 100 percent between the regions with the highest and lowest rates.
  • Compared with adults 18-44 years of age, the elderly are more likely to be hospitalized for the long-term complications of diabetes but less likely for short-term complications.
  • Women are 50 percent less likely than men to experience diabetes-related lower extremity amputations during hospitalization.
  • Dramatic differences exist across community income groups; residents from the lowest income areas have the highest rates of hospitalization for all diabetes-related conditions.
  • Although admission rates for most diabetes-related indicators do not vary by patient residence, rural residents are more likely than urban dwellers to be admitted to the hospital for uncontrolled diabetes without complications.

Select for Figures 7-12 (Adult Admissions for Diabetes-Related Conditions).

Circulatory Diseases: Congestive Heart Failure, Hypertension, and Angina Without a Procedure


Congestive heart failure, hypertension, and angina without a procedure are related to the priority areas identified by the Institute of Medicine for improving the health of the U.S. population.9

People suffering from congestive heart failure (CHF) typically have high rates of hospitalization. The elderly are at especially high risk for this condition. In fact, CHF is the most frequent discharge diagnosis among Medicare beneficiaries. In 1999, Medicare paid $3.6 billion for treatment of this disease. Furthermore, approximately 5 million Americans of all ages have been diagnosed with CHF; the associated costs amount to nearly $29 billion.10

Hypertension has also sparked great concern within the U.S. This condition now affects more than 50 million Americans, representing roughly 25 percent of the adult population.11 According to the American Heart Association, the lifetime risk of developing hypertension is approximately 90 percent for adults between ages 55 and 65; one-third of those affected are not even aware they have this condition.12-13 In 2004, the total cost of treating hypertensive patients was estimated to be $55.5 billion, and 75 percent of these expenses were allocated for direct medical costs.14

While less widespread, angina without a procedure persists as a significant health condition in the U.S. In 2001, approximately 7 million people were diagnosed with angina.15 The American Heart Association estimates that 27 percent of men and 14 percent of women will develop this condition within 6 years of experiencing a heart attack.16 While not all angina admissions are preventable, it may be possible to effectively manage this condition on an outpatient basis if diagnostic procedures and/or surgical interventions are not required.

Although occasional hospitalization may be necessary, each of these conditions can usually be controlled in outpatient settings. Patient compliance with treatment and appropriate lifestyle behaviors may lower the likelihood of hospitalization, and admission rates may be further reduced by ensuring access to high quality outpatient care.

  • Admission rates for angina without a procedure decreased markedly between 1994 and 2000, dropping by 71 percent (to 66 admissions per 100,000 population).iv
  • Regional variation is greatest among hypertension admissions; hospitalization rates in the South are nearly twice as high as rates in the West, the region characterized by the lowest admission rates.
  • The likelihood of hospitalization increases as community income decreases; this inverse relationship is most apparent for treatment of CHF.
  • Rural residents are 87 percent more likely than urban residents to be admitted for treatment of angina without a procedure.

Select for Figures 13-18 (Adult Admissions for Circulatory Diseases).

Respiratory Diseases: Adult Asthma, Pediatric Asthma, and Chronic Obstructive Pulmonary Disease


The number of Americans diagnosed with asthma has more than doubled since 1985; by 2000, more than 25 million Americans had been diagnosed with this chronic condition.17-18 Vulnerable populations at highest risk of acquiring asthma include children and low-income persons.19 The American Lung Association reports that total national direct costs amount to more than $9 billion annually, while indirect costs arising from lost productivity equal approximately $4.5 billion.20 Despite the vast resources spent on treating this disease, asthmatic patients continue to experience serious consequences. Each year, asthma results in nearly 2 million visits to the emergency room and roughly 5,000 deaths.21 Death from asthma sparks particular concern because this outcome is almost always avoidable with timely and effective care.

While asthma prevalence has increased over time, hospitalizations for this condition improved between 1994 and 2000. However, current admission rates still fall short of the objectives set forth by the U.S. Department of Health and Human Services. In its report, Healthy People 2010, the Department establishes target hospitalization rates of 77 per 100,000 population for people ages 5-65 years, and 25 per 100,000 population for children under the age of 5 years.22 Although the PQIs focus on different age groups, the results presented in the following pages illustrate that more work is needed to attain these goals. In 2000, admission rates were 201 per 100,000 children 0-17 years of age, and 113 per 100,000 adults 18 years and older.

Chronic obstructive pulmonary disease (COPD) also warrants attention, particularly because of the large number of cases that are not diagnosed. In 2001, when more than 12 million adults were diagnosed with COPD, experts estimate that an additional 16 million remained undiagnosed and, therefore, untreated.23-24 Failure to treat patients with COPD is a significant problem because this disease can be fatal. In fact, COPD is the fourth leading cause of death in the United States.25 Furthermore, COPD is a costly disease. In 2000, national COPD costs totaled more than $32 billion; this amount was split nearly evenly between direct and indirect costs.26

For most populations, asthma and COPD can often be managed with proper outpatient therapy, patient compliance with treatment, and abstinence from smoking. These factors, combined with access to high quality primary and preventive care, can reduce the severity of these conditions and the need for hospitalization.

  • Admission rates for asthma improved over time: adults experienced a steady decline in admissions between 1994 and 2000, and children were much less likely to be hospitalized in 2000 than in 1997.
  • COPD admissions rose substantially during the 6-year study period; hospitalization rates increased by 20 percent.
  • Variation in hospitalizations is most dramatic for treatment of COPD; hospitalization rates in the West are nearly half the rates observed in the South, the region with the highest admission rates.
  • Likelihood of admission is related to patient age: children below the age of 5 are 2 to 6 times more likely to be hospitalized for asthma than are older children, and adults 65 and above are more than 4 times more likely to be admitted for COPD than adults 45-64 years of age.
  • Adult asthma admission rates are 2.5 times higher for women than for men, whereas pediatric asthma admission rates are nearly one-third lower for girls than for boys.
  • For each of the 3 respiratory diseases, hospital admission rates decline as community income rises; rates are more than 2 times higher for residents of low-income areas than for residents of the highest income areas.

Select for Figures 19-25 (Admissions for Respiratory Diseases).

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Acute Conditions

Bacterial Pneumonia, Dehydration, Urinary Tract Infections, Perforated Appendix, and Pediatric Gastroenteritis


Several acute conditions pose significant challenges for the U.S. health care system. Many of these, such as bacterial pneumonia, dehydration, urinary tract infections, and perforated appendix, impact people of all ages. Each of these conditions may pose greater risks for specific subgroups, and others may target limited populations. For example, gastroenteritis is considered a potentially serious health problem among children.

The most common form of bacterial pneumonia is pneumococcal pneumonia, which accounts for 9 out of 10 disease cases. This condition results in as many as 800,000 hospitalizations each year.27 Older Americans are particularly susceptible, although research indicates that vaccines can be 45 percent effective in preventing the need for hospitalization among this population during peak seasons.28 Furthermore, this condition can often be treated with antibiotics, and prompt, effective outpatient treatment can help prevent unnecessary hospital admissions.

Certain populations are especially vulnerable to dehydration, including older Americans and very young children. This condition can often be treated in outpatient settings and, in many cases, hospital treatment may be unnecessary. However, inadequate treatment can result in serious complications, including mortality.29

Urinary tract infections (UTIs) are most common among women, although some men may also experience these types of infections. Estimates indicate that 50 to 80 percent of women develop at least 1 UTI during their lifetime, compared with 12 percent of men.30-31 Approximately 20 to 50 percent of all women experience recurrent infections and each year 11 percent of American women report suffering from UTIs.32-33 These infections are treated most frequently with antibiotics; the annual national cost of UTI prescriptions was estimated at more than $1.5 billion in 1995.34

Perforated appendix occurs when appropriate treatment for acute appendicitis is delayed. Delays may arise from providers' misdiagnosis, a patient's failure to interpret symptoms as important, or system factors preventing timely access to surgery (e.g., hospital surgical rooms are occupied when needed). On the other hand, prompt diagnosis and treatment generally prevent the progression of acute appendicitis to rupture and, thus, reduce the incidence of perforated appendix. Consequently, hospitalizations involving treatment for this condition suggest difficulties in 1 or more of the previously described areas.

Pediatric gastroenteritis is the irritation and inflammation of a child's digestive tract and can be the result of a number of factors, including food poisoning, viral infection, and intestinal parasites. This condition is often treatable in primary care settings with proper hydration and high quality care. Yet, it remains one of the most common reasons for hospitalization among children. Each year, pediatric gastroenteritis accounts for approximately 10 percent of all hospitalizations for children under 5 years of age.35

Several factors can reduce the likelihood of contracting these conditions. Safe environmental surroundings and proper hygiene can help prevent exposure to many of these illnesses. In addition, if patients seek treatment soon after experiencing symptoms, and if physicians provide high quality treatment in outpatient settings, the need for hospitalization can be decreased significantly. Therefore, rates of hospital admission may be used to evaluate the quality of primary and preventive care, and lower admission rates may reflect better overall access and quality of care provided in outpatient settings.

  • Between 1994 and 2000, hospitalization rates for perforated appendix decreased 9 percent, rates for dehydration and urinary tract infection did not change substantially, and rates for bacterial pneumonia increased by 9 percent.
  • The South has the highest admission rates and the West has the lowest admission rates for 4 of 5 acute conditions.
  • Among hospitalizations involving treatment for perforated appendix, the Northeast has the lowest rate, while the 3 other Census regions have comparable rates of roughly 320 admissions per 100,000 population.
  • The likelihood of hospital admission is inversely related to community income: residents from the lowest income areas are more likely than residents of higher income areas to be hospitalized for each of the acute conditions.
  • Young children age 0-4 years are 6 to 11 times more likely to be hospitalized for pediatric gastroenteritis than older children.
  • Among adults, preventable hospitalization rates for acute conditions increase substantially with age. The elderly are 5 to 6 times more likely to be admitted for bacterial pneumonia, dehydration, and urinary tract infections than adults 45-64 years of age.
  • Compared with men, women have higher admission rates for dehydration and urinary tract infections but lower rates for bacterial pneumonia and perforated appendix.
  • Admission rates are higher among rural residents for 4 of 5 acute conditions: bacterial pneumonia, dehydration, urinary tract infection, and pediatric gastroenteritis.

Select for Figures 26-32 (Admissions for Acute Conditions).

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Birth Outcomes

Low-Weight Births


The proportion of newborns weighing less than 2,500 grams has increased steadily since the mid-1980s. By 2002, the rate of low-weight births reached the highest level observed over the past 3 decades. This trend may be partially explained by the increased use of assisted reproductive technologies, which often results in multiple births.36

At the same time, other factors influence the likelihood of low-weight birth, such as prenatal care. Because prenatal care is delivered in primary care settings, data on these services are not widely available. As a result, it is difficult to define and evaluate the effectiveness of adequate prenatal care. However, some studies have found that mothers who obtain prenatal care have fewer low-weight newborns than women who do not receive such preventive care.37 Research also suggests that the following factors may be particularly effective in preventing low-weight births: smoking cessation, proper maternal nutrition, and adequate treatment of maternal comorbidities.38

The Institute of Medicine classified pregnancy and childbirth as a priority area, and the U.S. Department of Health and Human Services' report, Healthy People 2010, established a goal of reducing the proportion of low birthweight infants to 50 per 1,000 of all newborns.39-40

  • The South has the greatest number of low-weight births per 100,000 neonates, while the West has the fewest; the West's low-weight birth rate is 15 percent below the average of the 3 other regions.
  • Low-weight birth rates decline with increasing community income; rates vary by one-third between residents of the highest and lowest income areas.
  • Rates of low-weight births are comparable between newborns with private insurance and those who are uninsured.v
  • Medicaid enrollees have higher low-weight birth rates than any other payer group; rates are 38 percent higher for newborns covered by Medicaid than for newborns with private insurance.

Select for Figures 33-38 (Low-Weight Births).

iv This decline in admissions may be related to several factors, including increased use of procedures; shifting care from inpatient to outpatient settings; improved clinical training, technology, and patient ability to recognize symptoms; and more effective drugs.
v When calculating admission rates, the Low-Weight Birth PQI uses the number of neonates in the denominator. Because HCUP databases provide the number of births, it is possible to calculate rates for each payer group and make comparisons. All other PQIs use population-based denominators, which are available through the U.S. Census, Current Population Survey, and Claritas Census projections. These data sources define payer groups differently than the HCUP databases; therefore, it is not possible to calculate admission rates by payer categories for all other PQIs.

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