Medical Expenditure Panel Survey Agency for Healthcare 

Research and Quality

STATISTICAL BRIEF #139 

September 2006 

Trends in the Use and Expenditures for 

COX-2 Inhibitors and Traditional 

Nonsteroidal Anti-inflammatory Drugs, 

1997–2003 

Jessica Banthin, PhD and Marc Zodet, MS 

Introduction 

Since their approval by the Food and Drug Administration (FDA) in 

1998, selective cyclooxygenase-2 inhibitors (COX-2 inhibitors) have

accounted for a growing proportion of prescriptions for the class 

containing all nonsteroidal anti-inflammatory drugs (NSAIDs).1

 COX2 inhibitors include drugs such as celecoxib (Celebrex) and rofecoxib 

(Vioxx). Although rofecoxib was withdrawn from the market in late

2004 due to adverse side effects associated with coronary problems,2

 celecoxib remains on the market and is widely prescribed. 

COX-2 inhibitors are reported to induce fewer adverse gastrointestinal side effects compared with other traditional NSAIDs such

as ibuprofen and naproxen.

3

 As a class, NSAIDs are used to treat 

pain and are commonly prescribed for treatment of arthritis.4

 

This Statistical Brief uses data from the Household Component of 

the Medical Expenditure Panel Survey (MEPS-HC) to document 

trends in use and expenditures for COX-2 inhibitors from 1997 to 

2003 in relation to trends for traditional NSAIDs. The analysis begins 

in 1997 in order to measure the level of spending and use of 

traditional NSAIDs before COX-2 inhibitors were introduced. The 

brief shows changes in the percentage of the population using COX2 inhibitors versus traditional NSAIDs. All trends are presented for 

the total civilian noninstitutionalized population and then separately 

for the Medicare noninstitutionalized population, who are heavier 

users of the NSAID class of drugs. This analysis is limited to spending on prescribed medications since 

MEPS-HC excludes expenditures for over-the-counter medications. All differences discussed in the text 

are statistically significant at the 5 percent level, unless otherwise specified. 

Highlights 

 Aggregate spending on 

COX-2 inhibitors climbed 

from zero in 1997, the year 

before their introduction, to 

$5.5 billion in 2003. 

 Expenditures for COX-2 

inhibitors accounted for 65.0 

percent of total spending on 

all NSAIDs by 2003. 

 The percentage of the total 

population using COX-2 inhibitors grew from zero percent in 1997 to 4.7 percent 

in 2003. Among Medicare 

beneficiaries, the percentage 

using COX-2 inhibitors increased to 12.5 percent by 

2003. 

 In 2003, average spending 

per user of COX-2 inhibitors

was about $399 per year 

while average spending per 

user of other NSAIDs was 

less than one-third this 

amount, at $125 per year.

1 Dai, C., Stafford, R., Alexander, C. 2005. National Trends in Cyclooxygenase-2 Inhibitor Use Since Market Release, Archives of 

Internal Medicine January 24, 2005,165(2):171-177. 2 Graham, D., Campen, D., Hui, R., et al. Risk of acute myocardial infarction and sudden cardiac death in patients treated with cyclooxygenase 2 selective and non-selective non-steriodal anti-inflammatory drugs: nested case control study. The Lancet, Volume 

365, Issue 9458, Pages 475-481. 3 Deeks, J. J., Smith, L. A., Bradley, M. D.. 2002. Efficacy, tolerability, and upper gastrointestinal safety of celecoxib for treatment of 

osteoarthritis and rheumatoid arthritis: systematic review of randomised controlled trials. BMJ 2002 Sep 21;325(7365):619. 4 Silverstein, F. E., Faich, G., Goldstein, J. L., et al. 2000. Gastrointestinal toxicity with celecoxib vs nonsteroidal anti-inflammatory

drugs for osteoarthritis and rheumatoid arthritis: the CLASS study: A randomized controlled trial. Celecoxib Long-term Arthritis 

Safety Study. JAMA 2000 Sep 13; 284(10):1247-55. 
Findings 

Aggregate spending on COX-2 inhibitors climbed from zero in 1997, before they were introduced, to $5.5 

billion in 2003, while aggregate spending on traditional NSAIDs showed little change (figure 1). Spending 

on traditional NSAIDs did not change significantly, moving from a level of $3.2 billion in 1997 to $3.0 

billion in 2003. When considered as a class, expenditures for COX-2 inhibitors accounted for 65.0 percent 

of total spending on all NSAIDs by 2003 (data not shown). 

Changes in aggregate spending reflect shifts over time in the percentage of the population using the two

types of NSAIDs. In 1997, about 10.9 percent of the noninstitutionalized population was prescribed at 

least one traditional NSAID (figure 2). This percentage fell slowly over time so that by 2003, about 8.2 

percent of the population was prescribed at least one traditional NSAID. In the same period, the percentage of the population using COX-2 inhibitors bounced from zero percent in 1997 to 5.2 percent in 2001 

and 4.7 percent in 2003. Among users of all types of NSAIDs, the percentage using a COX-2 inhibitor at 

least once during the year jumped from zero percent in 1997 to 39.9 percent in 2003 (data not shown). 

Changes in aggregate spending on all types of NSAIDs also reflect higher average spending per user of 

COX-2 inhibitors versus traditional NSAIDs. In 2003, average spending per user of COX-2 inhibitors was 

about $399 per year (figure 3). In 2003, average spending per user of traditional NSAIDs was less than

one-third this amount, at $125 per year. This difference reflects the higher prices of the newer COX-2 

inhibitors versus the older NSAID drugs.

Compared with the total population, Medicare beneficiaries are heavier users of NSAIDs. Furthermore, 

aged beneficiaries are more likely than younger adults to exhibit the risk factors associated with adverse 

gastrointestinal side effects from traditional NSAIDs.5

 Between 1997 and 2003, aggregate expenditures 

on COX-2 inhibitors by Medicare beneficiaries increased from zero to $2.7 billion (figure 4). Spending on 

other NSAIDs remained steady at $1.2 billion in 1997 and $1.2 billion in 2003. Just as with the entire 

population, COX-2 inhibitors accounted for 65 percent of total expenditures on the entire class of NSAID 

medicines (data not shown). 

About 19.3 percent of Medicare beneficiaries purchased at least one traditional NSAID in 1997 (figure 5), 

nearly double the purchase rate among the total population. By 2003, this rate had dropped to 14.8 

percent. During the same period, use of COX-2 inhibitors increased from zero percent of the Medicare 

population in 1997 to 12.5 percent in 2003. Among all users of NSAIDs in the Medicare population, more 

than half (50.2 percent) used at least one COX-2 inhibitor during the year (data not shown). In 2003, the 

average annual expenditure per beneficiary for COX-2 inhibitors was $505 compared with $188 for other 

NSAIDs (figure 6). 

Data Source

The estimates presented in this Statistical Brief were derived from the MEPS-HC 1997, 1999, 2001, and 

2003 full-year consolidated data files and the 1997, 1999, 2001, and 2003 prescribed medicines (PMED) 

files. Expenditures for COX-2 inhibitors and traditional NSAIDs were identified by linking the PMED files to 

the Multum Lexicon. 

Definitions 

Persons are defined as Medicare beneficiaries if they ever reported being enrolled in Medicare while in 

the survey. For analytic purposes, this classification also includes a very small number of persons aged 

65 and over who did not report Medicare coverage. 

About MEPS-HC 

MEPS-HC is a nationally representative longitudinal survey that collects detailed information on health 

care utilization and expenditures, health insurance, and health status, as well as a wide variety of social, 

5 Go, M. F. Drug injury in the upper gastrointestinal tract: nonsteroidal anti-inflammatory drugs. Gastrointest, Endocs, Clini N Am

2006 Jan;16(1):83-97. 
demographic, and economic characteristics for the civilian noninstitutionalized population. It is 

cosponsored by the Agency for Healthcare Research and Quality and the National Center for Health 

Statistics. 

For more information about MEPS, call the MEPS information coordinator at AHRQ (301-427-1656) or 

visit the MEPS Web site at http://www.meps.ahrq.gov/. 

References 

For a detailed description of the MEPS survey design, sample design, and methods used to minimize 

sources of nonsampling error, see the following publications: 

Cohen, J. Design and Methods of the Medical Expenditure Panel Survey Household Component. MEPS 

Methodology Report No. 1. AHCPR Pub. No. 97-0026. Rockville, Md.: Agency for Health Care Policy and 

Research, 1997. 

Cohen, S. Sample Design of the 1996 Medical Expenditure Panel Survey Household Component. MEPS 

Methodology Report No. 2. AHCPR Pub. No. 97-0027. Rockville, Md.: Agency for Health Care Policy and 

Research, 1997. 

Cohen, S. Design Strategies and Innovations in the Medical Expenditure Panel Survey. Medical Care,

July 2003: 41(7) Supplement: III-5–III-12. 

Suggested Citation 

Banthin, J. S. and Zodet, M. Trends in the Use and Expenditures for COX-2 Inhibitors and Traditional 

Nonsteroidal Anti-inflammatory Drugs, 1997–2003. Statistical Brief #139. September 2006. Agency for 

Healthcare Research and Quality, Rockville, Md. http://www.meps.ahrq.gov/papers/st139/stat139 

∗ ∗ ∗

AHRQ welcomes questions and comments from readers of this publication who are interested in 

obtaining more information about access, cost, use, financing, and quality of health care in the United 

States. We also invite you to tell us how you are using this Statistical Brief and other MEPS data and 

tools and to share suggestions on how MEPS products might be enhanced to further meet your needs. 

Please e-mail us at mepspd@ahrq.gov or send a letter to the address below: 

Steven B. Cohen, PhD, Director 

Center for Financing, Access, and Cost Trends 

Agency for Healthcare Research and Quality 

540 Gaither Road 

Rockville, MD 20850 
Source: Center for Financing, Access, and Cost Trends, AHRQ, Household Component of the Medical Expenditure Panel Survey,

1997, 1999, 2001, and 2003 full-year consolidated data files and the 1997, 1999, 2001, and 2003 prescribed medicines files.

Figure 1. Aggregate expenditures on NSAIDs,

COX-2 inhibitors versus other NSAIDs, 1997-2003

1.4

4.9

5.5

3.2

3.0

2.6

3.0

0 0

1

2

3

4

5

6

1997 1999 2001 2003

COX-2 Inhibitors Other NSAIDs

C

onstant 2003 d

ollars, billions

Source: Center for Financing, Access, and Cost Trends, AHRQ, Household Component of the Medical Expenditure Panel Survey,

1997, 1999, 2001, and 2003 full-year consolidated data files and the 1997, 1999, 2001, and 2003 prescribed medicines files.

Figure 2. Percentage of total population using

COX-2 inhibitors versus other NSAIDs, 1997-2003

2.0

5.2 4.7

10.9

9.4

8.6 8.2

0 0

2

4

6

8

10

12

1997 1999 2001 2003

COX-2 Inhibitors Other NSAIDs

Percent
Source: Center for Financing, Access, and Cost Trends, AHRQ, Household Component of the Medical Expenditure Panel Survey,

1997, 1999, 2001, and 2003 full-year consolidated data files and the 1997, 1999, 2001, and 2003 prescribed medicines files.

Figure 3. Average annual expenditures per user for 

COX-2 inhibitors versus other NSAIDs, 1997-2003

252

330

399

110 114 105 125

0 0

100

200

300

400

500

1997 1999 2001 2003

COX-2 Inhibitors Other NSAIDs

C

onstant 2003 d

ollars

Source: Center for Financing, Access, and Cost Trends, AHRQ, Household Component of the Medical Expenditure Panel Survey,

1997, 1999, 2001, and 2003 full-year consolidated data files and the 1997, 1999, 2001, and 2003 prescribed medicines files.

Figure 4. Aggregate expenditures on NSAIDs, COX-2 inhibitors

versus other NSAIDs, Medicare population,1997-2003

0.7

2.1

2.7

1.2 1.1

1.0

1.2

0 0

0.5

1

1.5

2

2.5

3

1997 1999 2001 2003

COX-2 Inhibitors Other NSAIDs

C

onstant 2003 d

ollars, billions
Source: Center for Financing, Access, and Cost Trends, AHRQ, Household Component of the Medical Expenditure Panel Survey,

1997, 1999, 2001, and 2003 full-year consolidated data files and the 1997, 1999, 2001, and 2003 prescribed medicines files.

Figure 5. Percentage of Medicare population using

COX-2 inhibitors versus other NSAIDs, 1997-2003

7.0

13.8

12.5

19.3

15.4

14.0 14.8

0 0

5

10

15

20

25

1997 1999 2001 2003

COX-2 Inhibitors Other NSAIDs

Percent

 

Source: Center for Financing, Access, and Cost Trends, AHRQ, Household Component of the Medical Expenditure Panel Survey,

1997, 1999, 2001, and 2003 full-year consolidated data files and the 1997, 1999, 2001, and 2003 prescribed medicines files.

Figure 6. Average annual expenditures per Medicare user

for COX-2 inhibitors versus other NSAIDs, 1997-2003

265

378

162

192 173 188

505

0 0

100

200

300

400

500

600

1997 1999 2001 2003

COX-2 Inhibitors Other NSAIDs

C

onstant 2003 d

ollars