Multiple Chronic Conditions in the United States

Christine Buttorff, Teague Ruder, and Melissa Bauman

C O R P O R A T I O N

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Preface

n 2014, 60 percent of Americans had at least one chronic Icondition, and 42 percent had multiple chronic conditions. These proportions have held steady since 2008. Americans with chronic conditions utilize more—and spend more on— health care services and may have reduced physical and social functioning. This chartbook updates previous versions with more recent data on the prevalence of multiple chronic conditions (2008–2014) and associated health care utilization and spending. It explores disparities in the prevalence of chronic conditions and associated utilization of health care services and analyzes functional or other limitations for those with multiple chronic conditions. This chartbook should be of interest to researchers, policymakers, and practitioners, as well as to the general public.

The authors would like to thank the Partnership to Fight Chronic Disease for providing support for this project. We also thank our reviewers, Chloe E. Bird, Ph.D., and Gerard F. Anderson, Ph.D., for lending their expertise to this report.

This research was conducted in RAND Health, a division of the RAND Corporation. A profile of RAND Health, abstracts of its publications, and ordering information can be found at www.rand.org/health.

I iv Contents

Preface...... iii

Figures and Tables...... v

Introduction...... 1

Methodology...... 3

Chapter 1: Prevalence of Multiple Chronic Conditions...... 5

Chapter 2: Health Service Use and Spending...... 13

Chapter 3: Functional Status of Adults with Multiple Chronic Conditions...... 18

Appendix: Detailed Methodology and Limitations...... 21

References...... 27

II v Figures and Tables

Figure 1.1. Percentage of U.S. Adults with Chronic Conditions, by Number of Chronic

Conditions (2014)...... 6

Figure 1.2. Prevalence of Multiple Chronic Conditions, by Age (2008–2014)...... 7

Figure 1.3. Prevalence of Multiple Chronic Conditions by Age and Gender (2014)...... 8

Figure 1.4. Percentage of U.S. Adults with One or More Chronic Conditions by

Race/Ethnicity (2014)...... 9

Figure 1.5. Prevalence of Top Chronic Conditions, 2014...... 10

Figure 1.6. Most Common Chronic Conditions in 2008 and 2014, Men...... 11

Figure 1.7. Most Common Chronic Conditions in 2008 and 2014, Women...... 12

Figure 2.1. Annual Service Utilization by Number of Chronic Conditions (2014)...... 14

Figure 2.2. Prevalence and Spending by Number of Chronic Conditions (2014)...... 15

Figure 2.3. Health Care Spending by Number of Chronic Conditions (2014)...... 16

Figure 2.4. Average Annual Health Care Expenditures, by Number of Chronic Conditions and Insurance Type...... 17

Figure 2.5. Out-of-Pocket Spending by Number of Chronic Conditions and Insurance Type...... 17

Figure 3.1. Functional, Physical, Social, and Cognitive Limitations, by Number of Chronic

Conditions (2014)...... 19

Figure 3.2. ADL, Instrumental ADL, and Cognitive Limitations by Age and Number of Chronic Conditions (2014)...... 20

Figure A.1. Prevalence of Multiple Chronic Conditions (2003–2014)...... 25

Figure A.2. Prevalence of Multiple Chronic Conditions in Adults Age 65 and Older, 2008–2013...... 26

Table A.1. Decision Rules for Imputing Masked Conditions...... 22

iii Introduction | 1 Introduction

ix in ten adult Americans had at least one chronic condition Sin 2014, the latest year for which data are available, and What is a chronic four in ten had more than one. As this chartbook shows, chronic condition? disease is a burden not only for these patients but also for the A chronic condition is a physical health care system overall. Those with multiple chronic conditions or mental health condition that have poorer health, use more health services, and spend more lasts more than one year and on health care—trends that have been stable since 2008. causes functional restrictions or requires ongoing monitoring or This chartbook assesses the prevalence of multiple chronic treatment.7 conditions in the United States and explores the associated When a patient has more than one health care utilization and medical spending. This version chronic condition—for example, updates and expands on previous editions: the Agency for diabetes, hypertension, and Healthcare Research and Quality’s (AHRQ’s) 2014 edition of mood disorders—treatment can be difficult to manage. Treatment the Multiple Chronic Conditions Chartbook,10 as well as previous strategies or drug regimens iterations from the Robert Wood Johnson Foundation and Johns may be similar—but can be 11, 12 Hopkins University. very different—and one chronic condition may be better managed The data confirm that the prevalence of multiple chronic than the others.1 conditions—that is, having two or more chronic diseases simultaneously—is highest among older adults. It also shows that women are more likely than men to have multiple chronic conditions, as many women live longer than men do. The

1 Introduction | 2

prevalence of multiple chronic conditions is higher in non- Hispanic whites than in other racial/ethnic groups, which may reflect differences in access to care, rather than in the actual prevalence of chronic disease. In addition, those with more conditions have greater reported functional, social, and cognitive limitations.

For policymakers, planning for the care of people with complex chronic conditions is increasingly urgent as baby boomers become eligible for Medicare. Previous work has shown that people with multiple chronic conditions face more financial obligations and functional limitations2, 3 and often have worse health outcomes.4, 5, 6 Other work has shown that people with multiple chronic conditions have higher hospital readmission rates7 and much higher health care expenses.8 Multiple physical health conditions can be difficult to manage, especially when coupled with depression or other mental health conditions. In addition, younger generations can be affected by the financial and social implications of caring for the millions of older Americans.9

2 Methodology | 3 Methodology

his study uses the Medical Expenditure Panel Survey T(MEPS) from AHRQ.13 MEPS is a publicly available, nationally representative sample of the U.S. civilian, noninstitutionalized population. It is important to note that institutionalized adults are excluded from the charts because they are not included in the MEPS data.

For the purposes of this chartbook, we define multiple chronic conditions as having two or more conditions. We used the MEPS survey weights to create nationally representative estimates.

We attempted to replicate the methods of earlier chartbooks. Similar to previous iterations, this version identifies distinct conditions using the Clinical Classification Software codes that are part of the MEPS dataset, which group individual International Classification of Diseases, ninth edition (ICD-9) diagnosis codes into distinct conditions.14 To identify which conditions are chronic, we used the Chronic Conditions Indicator, developed by Hwang and colleagues.15, 16

Most of the charts in this book use data from 2014, the most recent year available for adults 18 and older. In the 2007–2008 panels, MEPS added a set of questions specifically asking whether respondents had certain priority conditions; as a result, there is a marked increase in the reported prevalence of chronic conditions overall at this point. Therefore, we restrict the presentation of trends in prevalence of chronic conditions over time to 2008–2014.

Our results have several limitations that should be taken into account when using charts from this publication. The results may underestimate the prevalence of chronic conditions because the data do not include individuals living in institutions, who

3 Methodology | 4

may have a larger number of chronic conditions. While the population of institutionalized adults is small for those ages 18–64, older adults are more likely to be in long-term care facilities, so we may underestimate the prevalence among older adults. About 3 percent of adults 65 and older were in full-year long-term nursing care facilities in 2013, the latest year for which data are available from the Medicare Current Beneficiary Survey.17 Because MEPS is a survey that relies on respondents to report on their own health, the data may also underrepresent the actual prevalence of chronic disease if individuals are not aware that they have the condition. We can only measure the prevalence of those who have been treated or told by a health care provider that they have a chronic condition (also called the “treated prevalence”). Finally, it has been documented elsewhere that MEPS underestimates total spending on health care services, and the underestimate can be as much as 17.6 percent, depending on the service type.18 The estimates on average spending should, therefore, be interpreted with caution. Despite these limitations, MEPS is one of the best sources of data on U.S. health care utilization, spending, access to care, insurance coverage, and demographic information.

A full description of the methodology can be found in the appendix.

4 CHAPTER 1 Prevalence of Multiple Chronic Conditions

5 CHAPTER 1 | Prevalence of Multiple Chronic Conditions | 6

As of 2014, 60 percent of American adults had at least one chronic condition, and 42 percent had more than one chronic condition.

Figure 1.1. Percentage of U.S. Adults with Chronic Conditions, by Number of Chronic Conditions (2014)

12% of U.S. adults

had five or more Number of chronic conditions chronic conditions 5+

0 12%

7% 40% had no chronic 9% conditions

13%

18%

42% had more than one chronic condition 60% had at least one chronic condition

NOTE: Percentages may not total 100 because of rounding.

6 CHAPTER 1 | Prevalence of Multiple Chronic Conditions | 7

The prevalence of multiple chronic conditions is higher among older adults.

Over time, the prevalence of U.S. adults with multiple chronic conditions has remained steady, at around 42 percent.

Figure 1.2. Prevalence of Multiple Chronic Conditions, by Age (2008–2014)

81% 80 65 years and older

50% 50 45–64 years

42% 40 Overall

20 18% 18–44 years

PERCENTAGE OF ADULTS WITH MULTIPLE CHRONIC CONDITIONS CHRONIC MULTIPLE WITH ADULTS OF PERCENTAGE 10

0 2008 2009 2010 2011 2012 2013 2014

YEAR

7 CHAPTER 1 | Prevalence of Multiple Chronic Conditions | 8

Women ages 18 through 64 have a higher prevalence of multiple chronic conditions than men.

The presence of multiple chronic conditions increases with age for both genders. Because our estimates of prevalence are based on self-reported conditions, we do not know if the higher prevalence among women is a result of true differences in prevalence or of other factors, such as women being more likely to be diagnosed because they may visit their health care providers more often.19

Figure 1.3. Prevalence of Multiple Chronic Conditions by Age and Gender (2014)

90 Gender gap

80 Just over 100 million people have multiple chronic 82% 81% conditions, and 54 million of 70 them are women.

50 54%

47% 40

20 22%

PERCENTAGE OF ADULTS WITH MULTIPLE CHRONIC CONDITIONS CHRONIC MULTIPLE WITH ADULTS OF PERCENTAGE 10 14%

0 18–44 years 45–64 years 65 years and over

MEN WOMEN

8 CHAPTER 1 | Prevalence of Multiple Chronic Conditions | 9

Non-Hispanic whites have a higher reported prevalence of chronic conditions than other racial or ethnic groups.

One reason could be that nonwhite racial/ethnic groups have historically had less access to insurance and health care services, making it less likely that their conditions would be diagnosed or treated. The non-white population is also younger; however, we do age-adjust the data.

Figure 1.4. Percentage of U.S. Adults with One or More Chronic Conditions by Race/Ethnicity (2014)

63% 60 14-point gap 58% across racial/ethnic

50 groups 50% 49% The difference between racial/ethnic groups for those 40 with one chronic condition varies from a high of 63 percent for non-Hispanic 30 whites to a low of 49 percent for Hispanics.

10 PERCENTAGE OF ADULTS WITH ONE OR MORE CHRONIC CONDITIONS CHRONIC MORE OR ONE WITH ADULTS OF PERCENTAGE

0 Non-Hispanic Non-Hispanic Non-Hispanic Hispanic white black other

NOTE: Estimates have been age- adjusted for the overall U.S. age distribution.

9 CHAPTER 1 | Prevalence of Multiple Chronic Conditions | 10

Hypertension and high cholesterol were the most common chronic conditions in 2014.

Figure 1.5. Prevalence of Top Chronic Conditions, 2014

Hypertension 27.0%

Lipid disorders (e.g., high cholesterol) 21.6%

Mood disorders (e.g., depression, bipolar disorder) 11.9% Heavy on heart disease Diabetes mellitus 10.4% One in four U.S. adults has Anxiety disorders (e.g., anxiety, panic disorders, stress) 9.7% hypertension, and about one in five has Other upper respiratory high cholesterol. disorders (e.g., chronic 7.4% laryngitis, chronic sinusitis)

Inflammatory joint disorders (other than arthritis) 7.4%

Osteoarthritis 6.5%

Asthma 6.3%

Coronary atherosclerosis and other heart disease 4.8%

0 5 10 15 20 25 30 PERCENTAGE

10 CHAPTER 1 | Prevalence of Multiple Chronic Conditions | 11

For women, the prevalence of anxiety disorders increased the most between 2008 and 2014, while hypertension increased the most for men.

The prevalence of hypertension increased by 2.5 percentage points for men, and anxiety disorders increased by 4.4 percentage points for women. The reported prevalence of mental health conditions also increased from 2008 to 2014.

Figure 1.6. Most Common Chronic Conditions in 2008 and 2014, Men

MEN

24.9% Hypertension 27.4% *

Lipid disorders 22.3% (e.g., high cholesterol) 23.0%

9.2% Diabetes mellitus 10.5% * 2.5-percentage- point increase Mood disorders (e.g., 6.6% depression, bipolar disorder) 8.6% * in hypertension among men Coronary 6.4% atherosclerosis and other heart disease 5.8%

Inflammatory joint disorders 6.1% (other than arthritis) 6.6%

Other upper respiratory 5.9% disorders (e.g., chronic laryngitis, chronic sinusitis) 5.8%

Anxiety disorders (e.g., 4.4% anxiety, panic disorders, stress) 6.3% *

4.3% Asthma 4.5% 2008 Other upper respiratory 3.8% infections (e.g., specific 2014 types of chronic sinusitis) 3.9%

0 5 10 15 20 25 30 PERCENTAGE

* Differences are significant at the p < 0.05 level or below. 11 CHAPTER 1 | Prevalence of Multiple Chronic Conditions | 12

From these data, we are unable to determine whether the apparent uptick in reported mental health conditions reflects an increase in diagnosis and reporting (possibly stemming from a decrease in stigma) or an increase in the prevalence of the diseases.

Figure 1.7. Most Common Chronic Conditions in 2008 and 2014, Women

WOMEN

26.5% Hypertension 26.5%

21.8% Lipid disorders * 20.3% (e.g., high cholesterol)

12.9% Mood disorders (e.g., * 15.1% depression, bipolar disorder)

9.3% Other upper respiratory disorders (e.g., chronic 9.0% laryngitis, chronic sinusitis)

9.3% Diabetes mellitus 4.4-percentage- * 10.3% point increase 8.4% Anxiety disorders (e.g., anxiety, panic disorders, in anxiety * 12.8% stress) disorders among 8.2% Osteoarthritis women 8.7%

7.8% Inflammatory joint disorders 8.2% (other than arthritis)

7.2% Asthma * 8.0% 2008 7.2% Other upper respiratory 2014 infections (e.g., specific 6.7% types of chronic sinusitis)

30 25 20 15 10 5 0 PERCENTAGE

* Differences are significant at the p < 0.05 level or below. 12 CHAPTER 2 Health Service Use and Spending

13 CHAPTER 2 | Health Service Use and Spending | 14

Health service use and spending is higher for those with chronic conditions than for those who are healthy.

The more chronic conditions people have, the more they use services of all types. As one example, those with five or more chronic conditions use twice as many drugs on average per year, compared with those with three or four conditions. As another, people with five or more conditions averaged 20 doctor visits per year, compared with 12 visits for those with three or four conditions.

Figure 2.1. Annual Service Utilization by Number of Chronic Conditions (2014)

EMERGENCY DEPARTMENT VISITS INPATIENT STAYS 35 35 32%

30 30

25 25 24% 20% 20 20

14% 15 15

10%

10 INPATIENT STAY 10 7% 6%

5 5 3% PERCENTAGE WITH LEAST AT ONE PERCENTAGE WITH LEAST AT ONE ED VISIT 0 0 0 1–2 3–4 5+ 0 1–2 3–4 5+

NUMBER OF CHRONIC CONDITIONS NUMBER OF CHRONIC CONDITIONS

PRESCRIPTIONS OUTPATIENT VISITS 60 25

51 20 50 20

40 15 12 30 24 10 20 6 AVERAGE NUMBER OF OF NUMBER AVERAGE PRESCRIPTIONS FILLED

9 VISITS OF NUMBER AVERAGE 5 10 2 1 0 0 0 1–2 3–4 5+ 0 1–2 3–4 5+

NUMBER OF CHRONIC CONDITIONS NUMBER OF CHRONIC CONDITIONS

NOTES: Average utilization is presented; not everyone uses a14 particular service in a given year, especially inpatient stays and ED visits. The number of prescriptions represents the total number of fills, including refills, not necessarily unique active ingredients, such as acetaminophen or ibuprofen. CHAPTER 2 | Health Service Use and Spending | 15 Americans with five or more chronic conditions make up 12 percent of the population but account for 41 percent of total health care spending.

Figure 2.2. Prevalence and Spending by Number of Chronic Conditions (2014)

100

12% 90

80 16% 41%

70 Number of chronic conditions

60 3–4 31% 1–2 0 50 26% PERCENTAGE

20 40% 23% NOTE: Total health care spending defined as the amount spent on all outpatient and 10 inpatient health care services across all payers, including out- 10% of-pocket payments.

0 Percentages may not total 100 Total population Total expenditures because of rounding.

15 CHAPTER 2 | Health Service Use and Spending | 16

People with chronic conditions have higher health care spending.

Those with five or more chronic conditions spend twice as much on average as those with three or four conditions, with the majority of that additional spending going to office visits, inpatient visits, and prescriptions.

Figure 2.3. Health Care Spending by Number of Chronic Conditions (2014)

20,000

18,000 14 times more spending On average, Americans with 16,000 five or more chronic conditions spend 14 times more on health services than people with no 14,000 chronic conditions.

12,000 Other

Home health 10,000 Prescription

8,000 Office and outpatient

Inpatient

6,000 AVERAGE ANNUAL SPENDING PER PERSON IN DOLLARS 4,000

NOTE: Total health care spending is defined as the amount spent on 2,000 health care services across all payers, including patient out-of-pocket payments. 0 0 1–2 3–4 5+ Average utilization is presented; not everyone uses a particular service in NUMBER OF CHRONIC CONDITIONS a given year, especially inpatient stays and ED visits.

16 CHAPTER 2 | Health Service Use and Spending | 17

Spending on health care services increases with number of chronic conditions but varies by insurance type.

Figure 2.4 displays payments for health care spending from other payers, such as Medicare or private insurance. An important caveat is that this figure does not account for other social supports to manage chronic conditions, such as unpaid caregiving from family members.

Figure 2.4. Average Annual Health Care Expenditures, by Number of Chronic Conditions and Insurance Type

$17,640 $8,867 Medicare $5,272 $1,973

$20,763 $9,864 Other public $4,107 $1,397

$18,351 $8,349 Private $4,241 $1,533 Number of chronic conditions 0 5,000 10,000 15,000 20,000 25,000 DOLLARS 5+ Figure 2.5 Out-of-Pocket Spending by Number of Chronic Conditions and 3–4 1–2 Insurance Type 0

$1,792 $1,137 Medicare $741 $378

$808 $640 Other public $242 $92

$1,741 $1,201 Private $698 $295

2,000 1,750 1,500 1,250 1,000 750 500 250 0 17 DOLLARS CHAPTER 3 Functional Status of Adults with Multiple Chronic Conditions 18 CHAPTER 3 | Functional Status of Adults with Multiple Chronic Conditions | 19 Individuals with more chronic conditions have greater difficulties with activities of daily living (ADL) and other social and cognitive functions that are important to patients’ independence.

People with five or more conditions have more than double the number of these limitations than those with three or four conditions, and the greater functional limitations place higher demands on caregivers and the health care system. Figure 3.1. Functional, Physical, Social, and Cognitive Limitations, by Number of Chronic Conditions (2014)

NEED HELP WITH ADL NEED HELP WITH INSTRUMENTAL ADL WORK/HOME/SOCIAL LIMITATIONS 60 60 60

50 50 50 42% 40 40 40

30 30 30

20 20 18% 20 19%

11%

PERCENTAGE OF U.S. ADULTS 10 PERCENTAGE OF U.S. ADULTS 10 PERCENTAGE OF U.S. ADULTS 10 6% 6% 3% 2% 0% 1% 0% 1% 0 0 0 0 1–2 3–4 5+ 0 1–2 3–4 5+ 0 1–2 3–4 5+ NUMBER OF CHRONIC CONDITIONS NUMBER OF CHRONIC CONDITIONS NUMBER OF CHRONIC CONDITIONS

PHYSICAL LIMITATIONS SOCIAL LIMITATIONS COGNITIVE LIMITATIONS

60 60 60

51% 50 50 50

40 40 40

30 30 30 25% 23% 23%

20 20 20

9% 10% 10% PERCENTAGE OF U.S. ADULTS 10 PERCENTAGE OF U.S. ADULTS 10 PERCENTAGE OF U.S. ADULTS 10 3% 4% 2% 1% 1% 0 0 0 0 1–2 3–4 5+ 0 1–2 3–4 5+ 0 1–2 3–4 5+

NUMBER OF CHRONIC CONDITIONS NUMBER OF CHRONIC CONDITIONS NUMBER OF CHRONIC CONDITIONS

NOTES: ADL include such basic functions as being able to bathe, dress, eat, go to the bathroom, or do light activity—for example, walking up a flight of stairs. Instrumental ADL include light housework, preparing meals, paying bills, and shopping. We used the composite variables constructed in MEPS for the ADL and IADL, which indicate whether a person reported needing supervision to complete at least one ADL or instrumental ADL activity. A work/school/home limitation is defined19 as an impairment or a physical or mental health problem that limits a person’s ability to work at a job, do housework, or go to school. A physical limitation is defined as having difficulties walking, climbing stairs, grasping objects, bending, or standing for long periods of time. MEPS defines social limitations as whether a person has trouble participating in social or family activities because of a physical or cognitive impairment. A cognitive limitation exists if the person has trouble with memory, is easily confused, has trouble making decisions, or needs to be supervised for his or her own safety. CHAPTER 3 | Functional Status of Adults with Multiple Chronic Conditions | 20

Older adults have more limitations on their daily activities and cognitive health than younger people.

Figure 3.2. ADL, Instrumental ADL, and Cognitive Limitations by Age and Number of Chronic Conditions (2014)

ADL LIMITATIONS INSTRUMENTAL ADL LIMITATIONS 25 25

21% 20 20

14% 15 15 13%

10 9% 10 9% 7%

5% 4% 4% 5 5 3% PERCENTAGE OF U.S. ADULTS 2% 3% PERCENTAGE OF U.S. ADULTS 1% 0% 1% 0% 0 0 0 1–2 3–4 5+ 0 1–2 3–4 5+ NUMBER OF CHRONIC CONDITIONS NUMBER OF CHRONIC CONDITIONS

COGNITIVE LIMITATIONS Age 25% 25 18–64 years

21% 65 years and over

10% 10% 10 8% 25 percent

5 4% of adults under age 65 with PERCENTAGE OF U.S. ADULTS 3% five or more chronic conditions 1% 0 have cognitive limitations. 0 1–2 3–4 5+

NUMBER OF CHRONIC CONDITIONS

20 Appendix | 21 Appendix Detailed Methodology and Limitations

Data and Chronic Condition Identification

e used data from MEPS, a nationally representative Wsurvey of U.S. health and health care use administered by AHRQ.13 Most charts use data from 2014; charts that compare the change in the treated prevalence of conditions over time use data from 2008 through 2014. We use the term treated prevalence to indicate that the data are survey-reported and therefore may underestimate the true prevalence of a given disease. Similar to previous chartbooks, we use the Clinical Classification Software (CCS), which groups individual ICD-9 codes into clinically distinct conditions, such as “essential hypertension,” publicly available from the Healthcare Cost and Utilization Project.14 Chronic conditions were identified with Dr. Wenke Hwang’s publicly available Chronic Condition Indicator, which was also used for previous chartbooks.6, 16, 21 In contrast with the previous chartbook, we did not group together distinct CCS categories. Our results are similar even without grouping together such categories as essential hypertension (CCS 98) and hypertension with complications (CCS 99). A complete listing of ICD-9 codes associated with each CCS category is available from the Healthcare Cost and Utilization Project: https://www.hcup-us.ahrq.gov/toolssoftware/ ccs/AppendixASingleDX.txt.

For each person, we assigned a chronic condition indicator for the given CCS category if at least one of their ICD-9 codes in the CCS category was labeled as chronic in the Chronic Condition Indicator. This avoided overcounting multiple ICD-9s within the same CCS category. For example, if a person had two ICD-9s within the essential hypertension category (CCS 98), they were only counted as having one chronic condition of hypertension.

21 Appendix | 22

Most of the ICD-9s within a given category for the top ten chronic conditions are chronic in the CCI. There are a few, such as other upper respiratory infections, that have a smaller proportion of chronic ICD-9s within the CCS category.

Beginning in 2013, MEPS began masking certain three-digit ICD-9 codes in the medical condition file to protect individuals with rare conditions from possible identification. For a given observation, the CCS code is available, but the ICD-9 codes may be missing. The percentages of masked patient conditions were 6.1 percent in 2013 and 9.2 percent in 2014, as compared with less than 1 percent in 2012. The missing ICD-9s caused drops in the prevalence of certain conditions in 2013 and 2014 compared with previous years, since we were identifying chronic conditions from the ICD-9 level. While most CCS categories are considered entirely chronic or non-chronic, the masking makes it difficult to identify chronic conditions within CCS categories that have a mix of chronic and non-chronic conditions. To impute these masked conditions, we first calculated the percentage of the CCS category that was considered chronic using historical MEPS condition data from 2003 to 2012. We then used the decision rules shown in Table A.1 to determine whether a condition would be deemed chronic or non-chronic.

Table A.1. Decision Rules for Imputing Masked Conditions

Percentage of Cases Within the CCS Category That Were Chronic Number Number of Number of Conditions in of CCS Observations Observations Decision 2003–2012 Categories (2013) (2014) Rule

90–100% 37 2,573 2,651 Chronic

10.1– 89.9% 30 612 1,108 Non-chronic

0–10% 76 3,909 6,477 Non-chronic

22 Appendix | 23

As a sensitivity analysis, we tested assigning the middle category of cases (10.1 percent to 89.9 percent) to chronic instead of non- chronic. Because of the relatively small sample size of this group, the impact on our outcome measure of an individual’s number of chronic conditions was small. For example, the percentage of the population with at least one chronic condition in 2013 was 60.18 percent (if we assigned all middle cases to non-chronic) and 60.45 percent (if we assigned all middle cases to chronic), for a difference of just 0.27 percent. We set middle-category cases to non-chronic to provide a conservative estimate of chronic conditions. The decision rule for this set of CCS categories was then applied across all years of data to ensure the comparability of estimates from one year to the next. Therefore, our estimates may differ slightly from the estimates published in prior chartbooks. The list of CCS categories with missing ICD-9 codes is available from the authors upon request.

Limitations

While MEPS is one of the best national sources of health care spending and health status, it is important to highlight that it is a survey. As such, the data are potentially biased, particularly when it comes to underreporting health conditions. Because MEPS is a survey, chronic conditions are self-identified; therefore, prevalence estimates from MEPS represent the treated prevalence of a disease, which may be lower than the actual prevalence. As a result, there are notable differences between the treated prevalence for a given condition and the actual prevalence measure in datasets with a laboratory component, such as the National Health and Nutrition Examination Survey (NHANES). For example, the proportion of adults with hypertension in NHANES is 29 percent (2011–2014) versus our estimate of approximately 26 percent for men and women for 2014.22

23 Appendix | 24

Two other limitations of note: The first is that MEPS only surveys civilian and noninstitutionalized Americans. As a result, we are missing the treated prevalence of disease in these groups. However, because the proportion of institutionalized adults is small, this may not markedly affect results. The Medicare Current Beneficiary Survey reports that approximately 3 percent of beneficiaries were in a long-term care facility in 2013.17 The second limitation is that MEPS likely underreports medical spending by about 17.6 percent, compared with the National Health Expenditures Accounts available from CMS, due to differences in the populations covered and services that are included in the totals and even in service category definitions.18 These limitations have been documented elsewhere by Bernard et al. (2012),18 and we highlight them so that readers interpret our results with caution.

As seen in Figure A.1, there is a marked uptick in the treated prevalence of chronic conditions between 2006–2007 and 2007– 2008, likely caused by a change in the questionnaire at that time to include a section on “priority conditions,” which directly asks respondents if a doctor has ever told them that they have a given disease. Previously, respondents would have had to volunteer the information. For this reason, we have limited our comparisons over time to 2008–2014.23

24 Appendix | 25

Figure A.1. Prevalence of Multiple Chronic Conditions (2003–2014)

81% 80 65 years and older

50% 50 45–64 years

20 18% 18–44 years

10 PERCENTAGE OF U.S. ADULTS WITH MULTIPLE CHRONIC CONDITIONS

NOTE: This figure documents the 0 prevalence of multiple chronic conditions (two or more) by age 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 group. The trend lines break YEAR at 2007 to indicate that MEPS changed its approach to the chronic disease questions. Comparison of the Trends in Chronic Disease in MEPS to Other Sources

Our estimates of the trend in chronic condition prevalence are flat for the period 2008–2014. This is consistent with other national datasets, notably the Medicare population from data tables of chronic conditions for fee-for-service beneficiaries from the Centers for Medicare & Medicaid Services (CMS) and the National Health Interview Survey (NHIS), both of which are publicly available (Figure A.2).24, 25 We did not examine particular individuals over time to determine whether they experienced more chronic conditions. While the prevalence has remained stable over time, the absolute numbers may have increased— particularly for older Americans, as the baby-boomer generation becomes eligible for Medicare.

25 Appendix | 26

Figure A.2. Prevalence of Multiple Chronic Conditions in Adults Age 65 and Older, 2008–2013

81% 80 MEPS

70% 70 CMS, women 66% CMS, men 61% 60 NHIS

SOURCE: Publicly available data on the prevalence of having two PERCENTAGE OF U.S. ADULTS AGE 65 AND OLDER WITH MULTIPLE CHRONIC CONDITIONS 0 or more chronic conditions from 2008 2009 2010 2011 2012 2013 NHIS, MEPS, and CMS for those YEAR age 65 and older.

Our estimates of the treated prevalence of disease are slightly higher than the CMS estimates for the prevalence of multiple chronic conditions for the population of those age 65 and older and are higher than the NHIS estimates. The differences are likely due to the number of chronic conditions included in the counts. We used the full list of chronic conditions corresponding to the granular CCS categories. The CMS analysis limits its analysis to 19 conditions, and NHIS limits its analysis to ten.

26 References | 27 References

1. Redelmeier, D. A., S. H. Tan, and G. L. Booth, "The Treatment of Unrelated Disorders in Patients with Chronic Medical Diseases," New England Journal of Medicine, Vol. 338, No. 21, 1998, pp. 1516–1520. 2. Wolff, J. L., C. Boult, C. Boyd, and G. Anderson, "Newly Reported Chronic Conditions and Onset of Functional Dependency," Journal of the American Geriatrics Society, Vol. 53, No. 5, May 2005, pp. 851–855. 3. Wolff, J. L., B. Starfield, and G. Anderson, "Prevalence, Expenditures, and Complications of Multiple Chronic Conditions in the Elderly," Archives of Internal Medicine, Vol. 162, No. 20, 2002, pp. 2269–2276. 4. Blumberg, L. J., T. A. Waidmann, F. Blavin, and J. Roth, "Trends in Health Care Financial Burdens, 2001 to 2009," Milbank Quarterly, Vol. 92, No. 1, 2014, pp. 88–113. 5. Caswell, K. J., T. Waidmann, and L. J. Blumberg, "Financial Burden of Medical Out-of-Pocket Spending by State and the Implications of the 2014 Medicaid Expansions," Inquiry, Vol. 50, No. 3, 2013, pp. 177–201. 6. Paez, K. A., L. Zhao, and W. Hwang, "Rising Out-of-Pocket Spending for Chronic Conditions: A Ten-Year Trend," Health Affairs, Vol. 28, No. 1, 2009, pp. 15–25. 7. Basu, J., R. Avila, and R. Ricciardi, "Hospital Readmission Rates in U.S. States: Are Readmissions Higher Where More Patients with Multiple Chronic Conditions Cluster?" Health Services Research, Vol. 51, No. 3, 2016, pp. 1135 –1151. 8. Cohen, S., "The Concentration of Health Care Expenditures and Related Expenses for Costly Medical Conditions, 2012," in MEPS Statistical Brief #455, Rockville, Md.: Agency for Healthcare Research and Quality, 2014. 9. Wolff, J. L., B. C. Spillman, V. A. Freedman, and J. D. Kasper, "A National Profile of Family and Unpaid Caregivers Who Assist Older Adults with Health Care Activities," JAMA Internal Medicine, Vol. 176, No. 3, March 2016, pp. 372–379. 10. Gerteis, J., D. Izrael, D. Deitz, L. LeRoy, R. Ricciardi, T. Miller, and J. Basu, Multiple Chronic Conditions Chartbook, AHRQ Publications No. Q14-0038, Rockville, Md.: Agency for Healthcare Research and Quality, April 2014. 11. Anderson, G., Chronic Care: Making the Case for Ongoing Care, Princeton, N.J.: Robert Wood Johnson Foundation, 2010. 12. Anderson, G., and J. Horvath, Chronic Conditions: Making the Case for Ongoing Care, Princeton, N.J.: Robert Wood Johnson Foundation, 2002. 13. Medical Expenditure Panel Survey, "Survey Background," last revised August 21, 2009. As of January 22, 2017: http://meps.ahrq.gov/mepsweb/about_meps/survey_back.jsp 14. Healthcare Cost and Utilization Project, "Clinical Classifications Software (CCS) for ICD-9-CM," last modified October 7, 2016. As of January 22, 2017: https://www.hcup-us.ahrq.gov/toolssoftware/ccs/ccs.jsp 27 References | 28

15. Healthcare Cost and Utilization Project, "Chronic Condition Indicator," last modified May 11, 2016. As of January 22, 2017: https://www.hcup-us.ahrq.gov/toolssoftware/chronic/chronic.jsp 16. Hwang, W., W. Weller, H. Ireys, and G. Anderson, "Out-of-Pocket Medical Spending for Care of Chronic Conditions," Health Affairs, Vol. 20, No. 6, November–December 2001, pp. 267–278. 17. Centers for Medicare & Medicaid Services, 2013 Characteristics and Perceptions of the Medicare Population, Medicare Current Beneficiary Survey, 2013. As of January 22, 2017: https://www.cms.gov/Research-Statistics-Data-and-Systems/Research/ MCBS/Data-Tables-Items/2013CNP.html?DLPage=1&DLEntries=10&DLSor t=0&DLSortDir=descending 18. Bernard, D., C. Cowan, T. Selden, L. Cai, A. Catlin, and S. Heffler, "Reconciling Medical Expenditure Estimates from the MEPS and NHEA, 20 07," Medicare & Medicaid Research Review, Vol. 2, No. 4, 2012. 19. Kaiser Family Foundation, "Gender Differences in Health Care, Status, and Use: Spotlight on Men’s Health—Findings from the 2013 Kaiser Men’s Health Survey and 2013 Kaiser Women’s Health Survey," Menlo Park, Calif., 2015. 20. Uberoi, N., K. Finegold, and E. Gee, Health Insurance Coverage and the Affordable Care Act, 2010–2016, Assistant Secretary for Planning and Evaluation, 2016. 21. Hwang, W., "Chronic Condition Classification," spreadsheet, 2009. As of January 22, 2017: http://www.icpsr.umich.edu/icpsrweb/content/AHRQMCC/shared-code. html 22. Yoon, S. S., C. D. Fryar, and M. D. Carroll, "Hypertension Prevalence and Control Among Adults: United States, 2011–2014," NCHS Data Brief No. 220, Centers for Disease Control and Prevention, November 2015. 23. Hall, A., and T. Highfill, "Calculating Disease-Based Medical Care Expenditure Indexes for Medicare Beneficiaries: A Comparison of Method and Data Choices," NBER Working Paper, National Bureau of Economic Research, 2013. 24. Centers for Medicare & Medicaid Services, Multiple Chronic Conditions Prevalence Tables, 2014. As of January 22, 2017: https://www.cms.gov/Research-Statistics-Data-and-Systems/Statistics- Trends-and-Reports/Chronic-Conditions/MCC_Main.html 25. Centers for Disease Control and Prevention, "Table 39. Number of Respondent-Reported Chronic Conditions from 10 Selected Conditions Among Adults Aged 18 and Over, by Selected Characteristics: United States, Selected Years 2002–2014," 2014. As of January 22, 2017: http://www.cdc.gov/nchs/hus/diseases.htm