The Economic Impact of Arthritis

Transcription

1 The Economic Impact of Arthritis Deborah P. Lubeck Introduction Arthritis and musculoskeletal disorders are the most prevalent of the major health problems of the United States population, affecting over 30 million people aged 45 years and older, about half of whom are over age 65 (1). While mortality from these conditions is low, they have a major effect on disability and medical care and their corresponding costs. Arthritis increases in prevalence with increasing age and is more common in women than men (2). As the average age of the population rises, the impact of arthritis will increase in parallel. A number of studies have noted that arthritis ranks first or second as a cause of long-term disability, work disability, restricted activity days, medical visits, and prescription and nonprescription drug use (2-7). For example, among working-age individuals, labor force participation was 20% to 25% lower among men and women with arthritis than among similar groups without arthritis (71. In 1988, arthritis and musculoskeletal conditions accounted for 12.8% of all hospitalizations in the United States, a frequency second only to diseases of the circulatory system (8). The most recent data on ambulatory care indicate that musculoskeletal conditions accounted for 13.8% of all office visits and were the largest disease-specific category (8). Arthritis results in significant direct costs for medical care, estimated at $12.7 billion, as well as total costs (including work loss and disability days) of $54.6 billion (8). Deborah P. Lubeck, PhD, Department of Medicine, Stanford University (currently, Technology Assessment Group, San Francisco, CA). Supported in part by a Multipurpose Arthritis and Musculoskeletal Diseases [Stanford Arthritis Center] grant (NIH-AR-20610) and a National Arthritis Data Resource (ARAMIS) grant (NIH-AR-21393) to Stanford University. Address correspondence to Deborah P. Lubeck, PhD, Technology Assessment Group, 490 Second Street, Suite 201, San Francisco, CA Submitted for publication February 1, 1995; accepted in revised form May 30, by the American College of Rheumatology. Clearly, arthritis dominates the national illness burden. Controlling health care costs has become a major policy objective in the United States. However, the impact of these disorders is poorly understood, even though reducing their effects could have a major bearing on the health of the population and the cost of health care services in the United States, and have important implications for those involved in the treatment of arthritis. In the following sections, the economic impact of two common forms of arthritis-rheumatoid arthritis (RA) and osteoarthritis (0A)-will be examined in order to gain a better understanding of how these disorders affect medical costs and indirect costs from lost earnings. Rheumatoid arthritis and osteoarthritis RA and OA have the greatest bearing on the direct costs (that is, expenditures for medical care, including help in the home or assistive devices] and indirect costs (that is, lost work, school, or leisure time resulting from a reduction or cessation in these activities) of arthritis (8,9). They are chronic illnesses, lasting an average of over 20 years. Disability and pain accumulate as joint destruction progresses. The determinants of the need for health services or the need to reduce usual activities are affected by the biology of the disease, the effectiveness of specific medical therapy, comorbid conditions, and patient behaviors, such as exercise, weight control, and self-management. RA is a progressive rheumatic disease that affects approximately 6.5 million Americans and is associated with significant pain and disability. Most persons with RA experience a lifetime of remissions and flares, requiring ongoing medical supervision. Medical management of RA involves frequent monitoring, including radiographs and blood chemistries. Fortunately, many therapeutic regimens produce measurable benefits and may modify the disease course. Aspirin and over-the-counter analgesics are generally used to relieve the initial symptoms of inflammation at a relatively low cost. However, many patients either cannot tolerate or do not receive sub /95/$5.00

2 Arthritis Care and Research Economic Impact of Arthritis 305 stantial relief with aspirin and must be treated with nonsteroidal anti-inflammatory drugs (NSAIDs), steroids, or disease-remittive agents, which contribute to increased medical expenditures. Other kinds of medical care utilization with significant costs include total joint replacement surgery, additional physician visits and diagnostic tests to monitor drug toxicity, and treatment for the side-effects of medications or surgical procedures. OA, the most common joint disease, has been shown repeatedly to correlate with pain, discomfort, and physical disability. The broader clinical syndrome of musculoskeletal disability represents the major illness burden. The impact of OA on lower extremity functioning is substantial, often necessitating total hip or knee replacement surgeries. Traditional treatment approaches to OA rely principally upon NSAIDs and, to a lesser extent, on analgesic agents such as acetaminophen. A recent survey indicated that over 90% of primary care physicians and rheumatologists would prescribe an NSAID as the initial treatment of OA (10). Despite their widespread use, the role of NSAIDs in the treatment of OA is not without controversy. The main reason that patients with OA seek medical care is for joint pain, but the source of the pain is often unclear. In some cases, it arises from the synovium, but Brandt has reported that there is a poor correlation between joint pain and synovitis (111. Thus, the pain relief reported with NSAID use may be due to its analgesic effects, rather than to an anti-inflammatory effect on the synovium, and NSAIDs may be no more effective than analgesics for the symptomatic treatment of OA (ll,l2). Costs of arthritis Health care costs are generally divided into three categories. Direct costs are expenditures for medical care and related items, including expenditures for physician visits, diagnostic tests, medications, hospital stays, and surgical procedures, among a long list of items. Direct costs also include expenditures on items such as transportation to and from the doctor, higher food bills associated with a special diet, care provided in the home, or expenditures to adapt the home environment to make daily activities easier to perform. Direct costs can be measured in many ways, including counting the number of health care services used and assigning a standard charge per service, or obtaining billing or insurance records for the actual amounts charged for each service or the amount reimbursed by the insurance company. Indirect costs are those costs associated with lost functioning in one s usual activities, which may in- clude work, schooling, parenting, or maintaining a household. These losses are usually measured using the human capital approach, which assigns a wage rate to work loss or disability days. For those nonmarket activities, such as homemaking or caring for a sick relative, there is no definitive method for assigning a dollar value. Intangible costs are costs associated with loss of physical functioning, mental health, increased pain, and reduced life quality. Only studies of the direct and indirect costs of arthritis are reviewed here. However, studies described below indicate that aspects of functioning and well-being are associated with the direct and indirect costs of arthritis. There have been a number of studies that describe the costs associated with arthritis (3,6,7,13-37). These studies have been of clinic-based populations, often from single institutions, or have been national surveys: both approaches have shortcomings. Research involving national random samples includes a more representative patient population than a clinic sample. However, in contrast to a clinic population, such studies rely on self-defined illness. The reliance on selfreport is likely to result in aggregation of inflammatory and non-inflammatory rheumatic conditions, inclusion of non-arthritic conditions, and the omission of undiagnosed patients. Yet, the patterns of health service utilization and the relationship between direct and indirect costs vary considerably between specific rheumatic conditions. For these reasons, the cost estimates from a national survey for a specific rheumatic disease, such as RA, are more likely to be imprecise than estimates from a clinic-based study. Also, unlike a national survey, a clinic-based study can provide greater detail on the specific resources utilized and has the potential to provide longitudinal data. National survey data Just over a decade ago, arthritis was estimated to affect 16 million Americans and to consume $21 billion annually ($13 billion for direct costs, in 1980 dollars], which represented 1% of the Gross National Product (GNP) and nearly 5% of all health care expenditures (3). This is likely a minimum estimate, as others have concluded that lost wages alone amount to $17 billion per annum (1984 dollars) (8). Musculoskeletal diseases accounted for 9% of all physician visits, 5% of all hospital discharges, and 15% of lost work days (3). Thirty years ago, the indirect costs of arthritis equaled or slightly exceeded the direct costs. By 1980, with the decline in the value of real wages, the rapid dissemination of expensive technologies, and the disproportionate inflation in the price of medical goods, direct

3 306 Lubeck Vol. 8, No. 4, December 1995 Table 1. Economic costs of rheumatoid arthritis, by study (in 1990 dollars)* Author, year (ref.)? Direct costs Indirect costs Total costs Meenan et al, 1978 (26) 5,767 (25%) 16,936 (75%) 22,703 (100%) Liang et al, 1984 (21) 1,776 (15%) 10,230 (85%) 12,006 (100%) Stone, 1984 (31) 10,938 (18%) 50,764 (82%) 61,702 (100%) Lubeck et al, 1986 (23) 5,064 NR NR Jacobs et al, 1988 (20) 1,958 NR NR * The cost estimates were updated to 1990 dollars by using the Consumer Price Index (Social Security Administration, 1991). t The estimates of 1990 costs for the first 3 studies (refs. 26, 21, and 311 were also reported by Yelin in ref. 5. The study by Jacobs et a1 (20) was based on costs for treatment in a Medicaid population. The study by Stone (311 used the incidence method for assigning costs. Indirect costs were not reported (NR] in the studies by Lubeck et a1 (23) and Jacobs et a1 (201. costs began to exceed indirect costs, even though labor force participation rates were declining more rapidly for persons with musculoskeletal diseases than for those with other conditions (5-7). Conservatively, RA alone is estimated to cost $1 billion (241. Symmetric polyarthritis, presumed to be a surrogate for RA and the inflammatory arthritides, resulted in an estimated $6.5 billion (1986 dollars) in lost earnings (28). Persons with RA incurred medical care costs 3 times as high, twice the rate of hospitalization, 4 times the number of ambulatory physician visits, and 10 times the work disability rate of an ageand sex-matched population (3). Estimates for OA indicate that patients account for 3.7 million hospital admissions, 185 million bed days, and 68 million work days lost each year (38). OA and related disorders accounted for more than half of all total hip replacements and 85% of all total knee replacements in 1989, and the total costs for knee and hip replacements that year were over $300 million (8). Clinic-based studies Several clinical studies of the costs of arthritis have been conducted. Table 1 summarizes the studies which report on expenditures for rheumatoid arthritis. These studies and others are discussed below. In each of the studies that evaluate both direct and indirect costs, the high costs of arthritis result primarily from the indirect costs associated with lost wages or leisure activity, rather than direct medical care expenditures. Direct costs. In studies conducted a decade ago, the annual resource consumption of an RA patient averaged $6,000 (updated to 1990 dollars) (22,23,26). Despite dissimilarities in the disease severity (i.e., stage 3 RA versus all in community, and university-based practices versus unremitting RA for 6 months), geographic locations, time intervals of self-report, and assignment of costs, the direct cost estimates are notably similar. Hospitalization rates varied from 6.5% of Medicaid RA patients to 26% of stage 3 RA patients, and accounted for 40% to more than 60% of direct costs (20,23,26,34,36]. Surgery was responsible for 54% of the admissions but 70% of the cost (34). Forty-seven percent of medical admissions were for evaluation and treatment, 43% for management of adverse effects of therapy, and 11% for complications of RA (34). For Medicaid patients, surgical hospitalization costs were 2.5 times higher than medical costs, but overall, hospitalization rates were lower than for other groups (6.5%) (20). Lower hospitalization rates for Medicaid patients may reflect more stringent admission and treatment criteria, especially for medical compared with surgical patients, amurig federal- and state-supported programs (20). Medications may constitute as much as 17% of total direct costs. There are approximately 20 NSAIDs, 7 or more agents commonly termed disease-modifying antirheumatic drugs (DMARDs) (i.e., injectable and oral gold, penicillamine, sulfasalazine, azathioprine, methotrexate, and hydroxychloroquine), and corticosteroids that the Food and Drug Administration has approved for the treatment of arthritis. The cost of drug treatment is often misinterpreted as the cost of the drug alone. This is not so. The long duration of therapy and associated monitoring can raise even relatively inexpensive drugs to significant expenditures. In one study, patients were prescribed DMARDs and were followed for 12 weeks; their visits for monitoring and treatment accounted for the major expense-over and above the cost of the drugs and routine physician visits (391. Using data from a survey of rheumatologists and decision analyses of frequency of treatment side effects, Prashker and Meenan estimated the costs of treating patients with DMARDs. They found that monitoring costs accounted for 40% to 70% of the costs, depending on the specific drug (40). Physicians and patients are also aware that there are adverse effects of pharmaceutical treatment. A

4 Arthritis Care and Research Economic Impact of Arthritis 307 study evaluating the reasons for hospitalizations of RA patients found that 42.5% of medical hospitalizations were for treatment of the side effects of therapy (34). Gastrointestinal side effects, such as bleeding or acid peptic symptoms, were the most common reasons for admission, followed by fracture related to corticosteroid therapy. In a different study, gastronintestinal side effects were also responsible for hospitalizations among 13% of patients treated with NSAIDs, resulting in hospital charges that were 8 times more than those in arthritis patients who did not have this adverse event (41). Among persons with OA, NSAIDs are also the drugs of choice. NSAID therapy and the costs of managing NSAID-inducted gastrointestinal complications (including ulceration, hemorrhage, and perforation) account for nearly 50% of the costs of treatment for OA (41). Persons who suffer gastrointestinal side effects may find some benefit from therapy that has been approved for use in the prevention of NSAID-induced gastropathy, including antiulcer medications and antacids (41). Indirect costs. In RA, indirect costs, as measured by the human capital approach, which assigns a value to work loss hours, have exceeded direct costs at least threefold, although there is evidence that this may be changing (5,21,26,31,32). Stone calculated the lifetime impact of arthritis to be approximately $16,000 per person (31). Indirect costs associated with productivity losses were 4 times greater than direct medical expenditures (31). Yelin reported that 50% of patients with RA suffered work force disability within 10 years of diagnosis (37). Of those individuals who stopped working, 10% indicated that before stopping work, they had tried such changes as reducing their hours at work or changing the type of work they performed; of those who continued working, about 25% had made changes (37). In a study of one clinic-based sample, Wolfe et a1 found that more than 75% of those who were employed at the onset of RA were still working 10 years later (42). Depression was a major predictor of work disability, Wolfe reported. Whether this halving of the rate of work disability in comparison to the study by Yelin is due to the evaluation of a more-rural population, to temporal changes in patients willingness to give up work, or to improvements in therapy is unknown. As indicated earlier, it is difficult to quantify disability in economic terms for those individuals who do not work. However, rates of disability appear to be as extensive among this group of individuals as among those who are employed. One study found that 50% of women with RA reported limitations in their usual activities (29). And Liang and colleagues reported that patients with both OA and RA reported some level of poorer physical functioning; 7% reported limited ability to conduct activities of daily living every day (21). In that study, patients also reported an average of 2.5 work disability days per month, and 30% indicated they had retired or were unemployed because of their arthritis (21). The human capital approach, based on the market value of work or home activities, tends to underestimate the work loss or disability days of older individuals and females. In a study by Thompson, which attempted to overcome this shortcoming, a clinic-based population of RA patients indicated they would be willing to pay 22% of their household income or about $5,000 annually for a complete cure (32). Surprisingly, although this methodology, known as willingness-topay, is presumed to incorporate additional financial burdens of the illness, such as the psychological impact and the impairment of non-labor force activity, it yielded results similar to the human capital approach. It is speculated that these additional dimensions were either of little importance or that respondents were unable to put into monetary terms the burden of illness. A study of patients with osteoarthritis cared for in different practices in the community found that health care expenditures ranged from approximately $830 per year to $2,300 per year (1984 dollars), depending on the site of care (43). Adjusting for medical inflation, the comparable costs in 1991 would have been $1,300 to $3,600 (44). While the medical costs for persons with OA are less than those for persons with RA, persons with OA represent a growing proportion of this country s aging population, and have experienced sharply escalating medical costs in recent years because of the increasing use of treatments such as total joint replacements. Determinants of the costs of arthritis Given that developing more effective health care management is a key to controlling expenditures, it is surprising that so little is known about how patient characteristics or site of care is associated with health care utilization for arthritis. In one of the few longitudinal studies on RA, the determinants of inpatient, outpatient, and total direct medical costs of this disease were evaluated (23). When controlled for age, sex, disease duration, and comorbid diseases, outpatient charges were predicted by functional disability, as measured by the Health Assessment Questionnaire, and inpatient and total charges were predicted by functional disability and global health. In this popu-

5 308 Lubeck Vol. 8, No. 4, December 1995 lation, disability status was positively related to hospitalization admission rate, and education level was inversely related to length of stay (35). In another of the few longitudinal studies examining direct costs for RA, Liang and colleagues noted that functional capacity at study entry determined direct costs (21). Hawley and Wolfe noted that baseline psychological scores predicted subsequent physician visits (45). Katz and Yelin also found that elevated depression scores in RA patients predicted higher frequencies for physician visits and hospitalizations (46). And, in a cross-sectional study, higher direct costs were observed in rheumatic disease patients with poorer psychological adjustment to illness (16). Cross-sectional and longitudinal studies have shown that in RA, work disability is more likely to develop in patients with more severe disease, less education, less social support, poorer psychological status, and more physically demanding j obs (27,29,37,42,47,48). The degree of autonomy over the job is noted as a particularly important determinant of work disability (6,27,29,48,49). These studies indicate that patient characteristics, such as poorer education, social support, and mental functioning, play a significant role in increasing health care utilization and work-related disability. The structure of health care delivery systems has been shown to affect health care costs. In the US, prepaid health care decreased the hospital admission rate by 34% for a group of RA patients; however, in the one Canadian center with a prospective global budget, and hence no constraint on length of stay, reported that stays were times those of the American centers (35). Another longitudinal study compared health services utilization and health outcomes for patients with RA treated by rheumatologists in different health care delivery systems-either a prepaid group practice or fee-for-service setting (36). The groups had similar rates of hospitalization, surgery, and length of stay for each admission, but the prepaid group practice had fewer ambulatory visits. After two years, the patients reported similar symptoms of illness, functional status, and work disability, but the fee-for-service patients reported poorer overall health status. The investigators speculated that the fee-for-service patients may have had higher expectations for their health. In a study of older individuals with OA, ambulatory care utilization was significantly lower in a community health program and in a health maintenance organization, than in traditional fee-for-service practices. The costs in 1991 were $1,297 per patient in the community health program, $1,718 in the health maintenance organization, and $3,640 in fee-for-service practices (44). Despite reduced utilization, pa- tients satisfaction with their care was higher in the community care program than in either the health maintenance organization or fee-for-service setting. In all three settings, health status generally deteriorated over the 4-year study period, but there were no significant differences across the three groups with regard to health outcomes, such as global health, pain, and disability. Discussion Controlling health care costs has become a major policy objective in the United States. Health care practices which reduce costs, while maintaining or improving quality of care and patient quality of life, are an essential need. The past two decades have witnessed numerous efforts to restrain the growth of expenditures for health care including: encouraging the development of managed health care programs, limiting reimbursement by standardizing fees according to diagnoses, imposing more cost-sharing on patients, and restricting patients eligibility for services and benefits. Innovations in clinical practice directed at controlling costs include the increased use of nurse practitioners, a shift to home and hospice care from inpatient care, an emphasis on early disease prevention, and patient education and self-management. An example of an alternative approach to care for arthritis is health education for self-management. A health education program, the Arthritis Self-Management Course, has been shown to reduce pain and depression, as well as demonstrate economic benefits in patients with arthritis. Over a period of four years, arthritis-related visits to physicians were reduced by 43% and pain was decreased by 19%; the estimated 4-year savings were $648 per RA patient and $189 per OA patient (50,51). A pilot study of an arthritis selfcare program delivered by mail, the SMART Program (Self-Management Arthritis Relief Therapy), also suggested both cost savings and clinical effectiveness (52). Both programs have been found to increase patient satisfaction, self-efficacy, and general health status, as well as constrain costs. The value of further research investigating the effect of health education on improving the outcomes associated with arthritis while reducing costs is evident. Similarly, studies described above, which indicate that the use of medical services and disability in arthritis is associated with patient well-being, emphasize the need for further study of the relationship between individual patient characteristics, health care utilization, and disability, especially for modifiable patient characteristics, such as mental functioning, work environment, and home environment. If economic con-

6 Arthritis Care and Research Economic Impact of Arthritis 309 cerns are to have relevance for clinical decision-making, the relationship between disease and therapy on the patient s health and well-being must be considered. Even though many studies have been published summarizing the costs of arthritis, there is still limited longitudinal data on how costs change at different points in the course or duration of disease. There are also scarce data on how resource utilization, global direct costs, and indirect costs of arthritis may be affected by new health care management strategies, a process that will certainly continue over the next decade. There is a need to continue to explore these issues in order to improve health care delivery and financing for these conditions which affect such a large and growing portion of our society. REFERENCES 1. 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