Reva C. Lawrence

Estimates of the prevalence of arthritis and other rheumatic conditions in the United States. Part II.

OBJECTIVE To provide a single source for the best available estimates of the US prevalence of and number of individuals affected by osteoarthritis, polymyalgia rheumatica and giant cell arteritis, gout, fibromyalgia, and carpal tunnel syndrome, as well as the symptoms of neck and back pain. A companion article (part I) addresses additional conditions. METHODS The National Arthritis Data Workgroup reviewed published analyses from available national surveys, such as the National Health and Nutrition Examination Survey and the National Health Interview Survey. Because data based on national population samples are unavailable for most specific rheumatic conditions, we derived estimates from published studies of smaller, defined populations. For specific conditions, the best available prevalence estimates were applied to the corresponding 2005 US population estimates from the Census Bureau, to estimate the number affected with each condition. RESULTS We estimated that among US adults, nearly 27 million have clinical osteoarthritis (up from the estimate of 21 million for 1995), 711,000 have polymyalgia rheumatica, 228,000 have giant cell arteritis, up to 3.0 million have had self-reported gout in the past year (up from the estimate of 2.1 million for 1995), 5.0 million have fibromyalgia, 4-10 million have carpal tunnel syndrome, 59 million have had low back pain in the past 3 months, and 30.1 million have had neck pain in the past 3 months. CONCLUSION Estimates for many specific rheumatic conditions rely on a few, small studies of uncertain generalizability to the US population. This report provides the best available prevalence estimates for the US, but for most specific conditions more studies generalizable to the US or addressing understudied populations are needed.

Estimates of the prevalence of arthritis and selected musculoskeletal disorders in the United States

OBJECTIVE To provide a single source for the best available estimates of the national prevalence of arthritis in general and of selected musculoskeletal disorders (osteoarthritis, rheumatoid arthritis, juvenile rheumatoid arthritis, the spondylarthropathies, systemic lupus erythematosus, scleroderma, polymyalgia rheumatica/giant cell arteritis, gout, fibromyalgia, and low back pain). METHODS The National Arthritis Data Workgroup reviewed data from available surveys, such as the National Health and Nutrition Examination Survey series. For overall national estimates, we used surveys based on representative samples. Because data based on national population samples are unavailable for most specific musculoskeletal conditions, we derived data from various smaller survey samples from defined populations. Prevalence estimates from these surveys were linked to 1990 US Bureau of the Census population data to calculate national estimates. We also estimated the expected frequency of arthritis in the year 2020. RESULTS Current national estimates are provided, with important caveats regarding their interpretation, for self-reported arthritis and selected conditions. An estimated 15% (40 million) of Americans had some form of arthritis in 1995. By the year 2020, an estimated 18.2% (59.4 million) will be affected. CONCLUSION Given the limitations of the data on which they are based, this report provides the best available prevalence estimates for arthritis and other rheumatic conditions overall, and for selected musculoskeletal disorders, in the US population.

Osteoarthritis: New Insights. Part 2: Treatment Approaches

There is no known cure for osteoarthritis, and the goal of contemporary management of the patient with osteoarthritis remains control of pain and improvement in function and health-related quality of life with avoidance, if possible, of therapeutic toxicity. Recent studies have demonstrated the potential of treatments ranging from newly approved oral medications to nutriceuticals, patient education interventions, and surgery. Increasingly, appropriate treatment of osteoarthritis combines one or more oral agents with exercise and other biomechanical techniques. This article is part 2 of a two-part summary of a National Institutes of Health (NIH) conference, Stepping Away from OA: Prevention of Onset, Progression, and Disability of Osteoarthritis. The conference brought together experts from diverse backgrounds and provided a multidisciplinary and comprehensive summary of recent advances in the prevention of osteoarthritis onset, progression, and disability. For research questions and opportunities identified at the conference, see www.nih.gov/niams/reports/oa/oareport.htm(accessed on 25 May 2000). Systemic and Topical Treatments Dr. Marc C. Hochberg (University of Maryland School of Medicine, Baltimore, Maryland), Dr. Timothy McAlindon (Boston University School of Medicine, Boston, Massachusetts), and Dr. David T. Felson (Boston University School of Medicine): Drug therapy for pain management is most effective when combined with nonpharmacologic strategies (1, 2). In 1995, the American College of Rheumatology issued guidelines for the medical management of osteoarthritis of the hip and knee (2, 3). Since then, several systematic reviews of drug therapy for osteoarthritis have been published (4-6). The following recommendations for systemic and topical treatments (except for glucosamine and chondroitin, which were not evaluated) are derived from updated recommendations of the American College of Rheumatology for the treatment of osteoarthritis. Systemic Treatments Nonopioid Analgesics For many patients with osteoarthritis, the relief of mild to moderate joint pain afforded by the simple analgesic acetaminophen is comparable to that achieved with a nonsteroidal anti-inflammatory drug (NSAID) (7, 8). Accordingly, although acetaminophen fails to adequately relieve pain in many patients, it merits a trial as initial therapy on the basis of its overall cost, efficacy, and toxicity profile (9, 10). The daily dose of acetaminophen should not exceed 4 g. Although it is one of the safest analgesics, acetaminophen can be associated with clinically important adverse events, such as prolongation of the half-life of warfarin (11). At therapeutic doses acetaminophen rarely causes hepatic toxicity, but it should be used cautiously in patients with existing liver disease and avoided in patients with chronic alcohol abuse because of known increased risk in these patients (12-14). Even though acetaminophen was reported to be weakly associated with end-stage renal disease, the Scientific Advisory Committee of the National Kidney Foundation recommended it as the drug of choice for analgesia in patients with impaired renal function (15). Tramadol, a centrally acting oral analgesic, is a synthetic opioid agonist that inhibits reuptake of norepinephrine and serotonin. It has been approved by the U.S. Food and Drug Administration for treatment of moderate to severe pain and can be considered for use in patients in whom acetaminophen therapy has failed and who have contraindications to NSAIDs, including the cyclooxygenase-2 (COX-2)specific inhibitors. Although numerous studies have examined use of tramadol to treat general pain, few controlled studies have examined its use in osteoarthritis. The efficacy of tramadol has been found to be comparable to that of ibuprofen in patients with hip and knee osteoarthritis (16), and it is useful as adjunctive therapy in patients with osteoarthritis whose symptoms were inadequately controlled with NSAIDs (17). Daily doses of tramadol have generally been in the range of 200 to 300 mg given in four divided doses. Side effects are common and include nausea, constipation, and drowsiness. Despite the opioid pharmacology of tramadol, a comprehensive surveillance program has failed to demonstrate significant abuse, and tramadol remains an unscheduled agent. Seizures have been reported as a rare side effect, either at doses above the recommended range or at doses within the recommended range in patients with a history of epilepsy and those taking concomitant medications that lower the seizure threshold. NSAIDs For patients who do not obtain adequate symptom relief with nonopioid analgesics, use of NSAIDs should be considered. The choice between a nonselective NSAID and a COX-2specific inhibitor should be made after evaluation of risk factors, particularly for upper gastrointestinal and renal toxicity. Data from epidemiologic studies show that among persons 65 years of age or older, 20% to 30% of all hospitalizations and deaths due to peptic ulcer disease were attributable to therapy with NSAIDs (18-20). Furthermore, the risk for a catastrophic gastrointestinal event in elderly patients taking NSAIDs is dose dependent (18). Risk factors for upper gastrointestinal bleeding in patients treated with NSAIDs include age 65 years or older, history of peptic ulcer disease or previous upper gastrointestinal bleeding, concomitant use of oral corticosteroids or anticoagulants, and possibly smoking and alcohol consumption (21-23). Risk factors for reversible renal failure in patients with intrinsic renal disease who are treated with NSAIDs include age 65 years or older, hypertension or congestive heart failure, and concomitant use of diuretics and angiotensin-converting enzyme inhibitors (24). Additional considerations involved in a practitioners decision to treat an individual patient with osteoarthritis include existing comorbid conditions and concomitant therapy, as well as the side effects and costs of specific treatments. The options for medical management of the patient with osteoarthritis who is at increased risk for a serious adverse upper gastrointestinal event, such as bleeding, perforation, or obstruction, are use of a COX-2specific inhibitor or a nonselective NSAID with gastroprotective therapy. Two COX-2specific inhibitors, celecoxib and rofecoxib, have been approved by the U.S. Food and Drug Administration for use in patients with osteoarthritis (25, 26). Celecoxib has been found to be more effective than placebo and as effective as naproxen for symptoms in patients with hip or knee osteoarthritis (27-29). Rofecoxib has also been found to be more effective than placebo and is comparable in efficacy to both ibuprofen and diclofenac in patients with hip or knee osteoarthritis (30, 31). Endoscopic studies have shown that celecoxib and rofecoxib are associated with an incidence of gastroduodenal ulcers lower than that of comparator NSAIDs and similar to that of placebo (25). These data suggest an advantageous safety profile compared with nonselective NSAIDs, especially for treatment of high-risk patients (21-23). However, no large long-term studies have been published that were designed to demonstrate differences between COX-2specific inhibitors and nonselective NSAIDs with respect to major gastrointestinal clinical outcomes; such studies are in progress. A further advantage of COX-2specific inhibitors with respect to upper gastrointestinal bleeding is that celecoxib and rofecoxib do not have a clinically significant effect on platelet aggregation or bleeding time. In addition, at doses recommended for treatment of osteoarthritis, these drugs appear to be better tolerated than comparator nonselective NSAIDs, with a lower incidence of dyspepsia and other gastrointestinal side effects. As with nonselective NSAIDs, however, COX-2specific inhibitors can cause renal toxicity. Caution must be exercised, therefore, if these drugs are used in patients with mild to moderate renal insufficiency, and they should not be used in patients with severe renal insufficiency. In addition, celecoxib is contraindicated in patients with a history of allergic reaction to a sulfonamide. The alternative to use of a COX-2specific inhibitor is use of a nonselective NSAID with a gastroprotective agent, an approach endorsed by the American College of Gastroenterology (23). As noted earlier, serious adverse upper gastrointestinal events attributed to NSAIDs in the elderly are dose dependent. Therefore, if nonselective NSAIDs are used, therapy should be begun at low, analgesic doses and increased to full anti-inflammatory doses only if lower doses do not provide adequate relief of symptoms. In a study of 8843 patients with rheumatoid arthritis, misoprostol at a dosage of 200 g four times daily reduced the incidence of serious ulcer complications, including perforation, bleeding, and obstruction, by 51% (32). In a 12-week randomized, double-blind, placebo-controlled endoscopy study, misoprostol at a dosage of 200 g three times per day had comparable efficacy in prevention of both gastric and duodenal ulcers; however, 200 g twice daily conferred significantly less protection against gastric ulcers (33). Side effects, particularly diarrhea and flatulence, may occur with this agent in a dose-dependent manner (33). Alternative approaches to prophylaxis with misoprostol include use of omeprazole or high-dose famotidine, both of which have been shown in carefully conducted endoscopy studies to be effective in treating and preventing NSAID-induced gastropathy (34-37). Histamine-2 blockers in usual doses, however, have not been found to be as effective as misoprostol (36), whereas omeprazole (20 mg/d or 40 mg/d) was as effective as misoprostol (200 g twice daily) in treatment of existing ulcers and was better tolerated and associated with a lower rate of relapse (37). Of note, proton-pump inhibitors have not been approved by the U.S. Food and Dr

Epidemiologic associations of pain in osteoarthritis of the knee: Data from the national health and nutrition examination survey and the national health and nutrition examination-i epidemiologic follow-up survey

0 STEOARTHRITIS (OA) is the most common joint disorderlm3; however, it is clear from numerous population studies that many persons with radiographic changes of OA have no symptoms or resulting disability.4-7 In 1981, Kelsey suggested that although “physical reasons must exist which explain this anomaly, . . . evidence [exists] that illness behavior also plays a role.“’ At the same conference, Kuller also commented on the occurrence of asymptomatic radiographic OA and noted that the study of factors linking disease with symptoms and disability was an important aspect that merited further study.9 He suggested that although “a simple relationship [might exist] between the severity of the joint disease and symptomatology, it is more likely that the behavioral characteristics of the individual and the type of activity engaged in are important determinants of the symptomatology and disability associated with the pathology.“’ The availability of national arthritis data, specifically the National Health and Nutrition Examination Survey (NHANES-I)7 and the Na-

WebMIRS: Web-based medical information retrieval system

At the Lister Hill National Center for Biomedical Communications, a research and development division of the National Library of Medicine (NLM), we are developing a prototype multimedia database system to provide World Wide Web access to biomedical databases. WebMIRS (Web-based Medical Information Retrieval System) will allow access to databases containing text and images and will allow database query by standard SQL, by image content, or by a combination of the two. The system is being developed in the form of Java applets, which will communicate with the Informix DBMS on an NLM Sun workstation running the Solaris operating system. The system architecture will allow access from any hardware platform, which supports a Java-enabled Web browser, such as Netscape or Internet Explorer. Initial databases will include data from two national health surveys conducted by the National Center for Health Statistics (NCHS), and will include x-ray images from those surveys. In addition to describing in- house research in database access systems, this paper describes ongoing work toward querying by image content. Image content search capability will include capability to search for x-ray images similar to an input image with respect to vertebral morphometry used to characterize features such as fractures and disc space narrowing.

Digital atlas for spinal x rays

At the National Library of Medicine we are developing a digital atlas to serve as a reference tool for the interpretation of cervical and lumbar spine x-rays. The atlas contains representative images for four grades of severity for cervical/lumbar spondylolisthesis. A prototype version of the atlas has been built using images for which expert rheumatologist readers reached exact agreement in grading. The atlas functionality includes the ability to display cervical and lumbar anatomy, display of single images or multiple simultaneous images, image processing functions, and capability to ad user-defined images to the atlas. Images are selected for display by the user specifying feature and grade. Currently, the atlas runs on a Sun SPARC workstation under the Solaris operating system. THe initial use of the atlas is to aid in reading a collection of 17,000 NHANES II digitized x-rays. The atlas may also be used as a general digital reference tool for the standardized interpretation of digital x-rays for osteoarthritis. We are investigating further development of the atlas to accommodate a wider set of images, to operate on multiple platforms, and to be accessible via the WWW.