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Centers for Disease Control and
Prevention National Institutes of Health |
The current and projected growth in the number of people aged 65 years and older in the United States has focused attention on preserving quality of life as well as length of life. Chief among the factors involving preserving quality of life are the prevention and treatment of musculoskeletal conditions—the major causes of disability in the United States. Among musculoskeletal conditions, arthritis and other rheumatic conditions, osteoporosis, and chronic back conditions have the greatest impact on public health and quality of life.
Demographic trends suggest that people will need to continue working at older ages (for example, beyond age 65 years), increasing the adverse social and economic consequences of the high rates of activity limitation and disability of older persons with these conditions. At the same time, effective public health interventions exist to reduce the burden of all three conditions. (See Focus Area 6. Disability and Secondary Conditions.)
The various forms of arthritis affect more than 15 percent of the U.S. population—over 43 million persons—and more than 20 percent of the adult population, making arthritis one of the most common conditions in the United States.[1], [2], [3], [4]
The significant public health impact of arthritis is reflected in a variety of measures. First, arthritis is the leading cause of disability.[5] Arthritis limits the major activities (for example, working, housekeeping, school) of nearly 3 percent of the entire U.S. population (7 million persons), including nearly 1 out of every 5 persons with arthritis.1, 2, 3 Arthritis trails only heart disease as a cause of work disability.[6] As a consequence, arthritis limits the independence of affected persons and disrupts the lives of family members and other caregivers.
Second, health-related quality-of-life measures are consistently worse for persons with arthritis, whether the measure is healthy days in the past 30 days, days without severe pain, “ability days” (that is, days without activity limitations), or difficulty in performing personal care activities.[7], [8]
Third, arthritis has a sizable economic impact. Arthritis is the source of at least 44 million visits to health care providers, 744,000 hospitalizations, and 4 million days of hospital care per year.4, [9] Estimated medical care costs for persons with arthritis were $15 billion, and total costs (medical care plus lost productivity) were $65 billion in 1992.[10] This latter amount is equal to 1.1 percent of the gross domestic product. Nearly 60 percent of persons with arthritis are in the working-aged population1, 2, 3 and they have a low rate of labor force participation.[11]
Fourth, arthritis, like other chronic pain conditions, has an important negative effect on a person’s mental health.[12], [13]
Fifth, although death is not a frequent outcome of arthritis, persons with certain forms of arthritis have higher death rates than the general population. For example, the 2 million persons in the United States with rheumatoid arthritis are at greater risk of premature death from respiratory and infectious diseases than the overall U.S. population.[14]
A variety of demographic trends indicate that the impact of arthritis will only increase.[15] Given current population projections, arthritis will affect over 18 percent of all persons in the United States (nearly 60 million persons) in the year 2020 and will limit the major activities of nearly 4 percent (11.6 million).1, 2, 3 Direct and indirect costs are expected to rise proportionately.
About 13 to 18 percent of women aged 50 years and older and 3 to 6 percent of men aged 50 years and older have osteoporosis, a reduction in bone mass or density that leads to deteriorated and fragile bones. These rates correspond to 4 million to 6 million women and 1 million to 2 million men in the United States who have osteoporosis.[16] Another 37 to 50 percent of women aged 50 years and older and 28 to 47 percent of men of the same age group have some degree of osteopenia, reduction in bone mass that is not as severe as osteoporosis.
The major health consequence of osteoporosis is an increased risk of fractures. Approximately 1.5 million fractures per year are attributed to osteoporosis.[17] One in three women and one in eight men aged 50 years and older will experience an osteoporotic-related fracture in their lifetime.17 Health care costs for these fractures are estimated at $13.8 billion per year in 1996 dollars.[18]
The risk of any fracture increases with the presence of osteoporosis, but hip fractures represent the most serious impact in terms of health care costs and consequences for the individual. In 1994, there were 281,000 hospital discharges for hip fracture among people aged 45 years and older. Of these, 74,000, or 26 percent, were among men.16 In all, 1 out of 6 white women and 1 out of 17 white men will experience a hip fracture by the time they reach age 90 years.[19] Although the hip fracture rate among women seems relatively constant, the rate among men seems to be increasing over time.[20]
An average of 24 percent of hip fracture patients aged 50 years and older die in the year following fracture, with higher death rates among men than among women.[21] Also, hip fracture is more likely to lead to functional impairment than are other serious medical conditions, including heart attack, stroke, and cancer.21 For example, half of all hip fracture patients will be unable to walk without assistance.17
Chronic low back pain is described in different ways, such as the occurrence of back pain lasting for more than 7 to 12 weeks, back pain lasting beyond the expected period of healing, or frequently recurring back pain. Moreover, a wide range of outcome measures are used to describe chronic back problems, such as low back pain (LBP), activity limitation, impairment, and disability. Compounding the problem is the lack of a single data source to track chronic back problems. Sources that have been used include workers compensation data, Occupational Safety and Health Administration and Bureau of Labor Statistics records, and data from national health surveys.
Chronic back conditions are both common and debilitating. Back pain occurs in 15 to 45 percent of people each year,[22], [23], [24], [25], [26] and 70 to 85 percent of people have back pain some time in their lives. In the United States, back pain is the most frequent cause of activity limitation in people under age 45 years,[27], [28] the second most frequent reason for physician visits, the fifth-ranking reason for hospitalization, and the third most common reason for surgical procedures.[29]
Work-related risk factors, such as heavy physical work, lifting and forceful movements, awkward postures, and whole body vibration, are associated with low back disorders. Work-related risk factors account for 28 to 50 percent of the low back problems in an adult population.[30] A number of personal factors may be risk factors for low back pain. These include nonmodifiable factors, such as age and gender, some anthropometric characteristics (for example, height and body build), history of low back problems, and spinal abnormalities as well as modifiable factors, such as weight, physical fitness, smoking, some aspects of lumbar flexibility, trunk muscle strength, and hamstring elasticity. A history of low back problems is one of the most reliable predictors of subsequent back problems.[31]
Arthritis is a leading health problem among all demographic groups, although significant and sometimes surprising disparities exist. Arthritis affects 50 percent of people aged 65 years and older. However, most people with arthritis are younger than age 65 years and of working age.1, 2, 3 Arthritis also affects 285,000 children,[32] making it one of the more common chronic conditions of childhood. Arthritis is more common in women aged 18 years and older than in men and is the leading chronic condition and cause of activity limitation among women.[33], [34]
Whites and African Americans have similar rates of disease, but African Americans have greater rates of activity limitation.1, 2, 3 For African Americans, arthritis is the third most common chronic condition and the leading cause of activity limitation.[35] For Hispanics and American Indians or Alaska Natives, arthritis is the second most common chronic condition and the second leading cause of activity limitation.35 For Asians or Pacific Islanders, arthritis is the fourth most common chronic condition and the second leading cause of activity limitation.35 For whites, arthritis is the most common chronic condition and the second leading cause of activity limitation.35
The rate of arthritis and its associated disabilities is higher among persons with low education and low income.1, 2, 3 African Americans have lower rates of total joint replacement, a surgical procedure that is highly successful in reducing the impact of arthritis in persons with severe pain or disability, than do whites.[36] Certain types of jobs, such as shipyard work, farm work, and occupations that place high knee-bending demands on workers, increase the risks for osteoarthritis.[37], [38]
Osteoporosis is more common among women than men. The rates of disease increase markedly with increasing age. Rates are higher among non-Hispanic white Americans than among Mexican Americans or non-Hispanic African Americans.16 White postmenopausal women are at highest risk of the disease.
The risk for chronic back pain increases with age. Although back pain appears to be equally common in men and women, impairment from back and spine conditions is more common in women.
The importance of physical activity for bone and joint health was highlighted in a 1996 report Physical Activity and Health: A Report of the Surgeon General.[39] Although behavioral interventions seem to have potential benefits, risk factors for the various types of arthritis need to be identified. Recreational or occupational joint injury has been identified as a risk factor for later osteoarthritis, and overweight is a risk factor for osteoarthritis of the knee and possibly the hip and hand.[40] Overweight appears to be a risk factor associated with the progression and severity of osteoarthritis.40, [41]
Genetic research may soon identify persons at high risk for certain types of arthritis and thereby offer a better target for interventions. Current medical care offers considerable relief from pain and other symptoms for all types of arthritis. Available interventions often are not used, however, because of the popular belief that arthritis is part of normal aging, that a person can do nothing about it, and that it affects only old persons. However, early diagnosis and aggressive treatment of rheumatoid arthritis with disease-modifying drugs, for example, appear to reduce its symptoms and related disability.[42], [43], [44], [45], [46], [47]
Educational and behavioral interventions also can relieve symptoms and reduce disability. Telephone contacts with clinicians and several land-based and water exercise programs have had beneficial outcomes.[48], [49], [50], [51] The Arthritis Self-Help Course, a 6-week, 2-hour per week educational intervention, has been shown to reduce pain up to 20 percent beyond what was achieved through conventional medical care.[52] The course has the additional benefit of reducing medical care costs by reducing the number of physician visits for arthritis.52, [53] These and other effective interventions currently are underused, with some reaching less than 1 percent of target populations.[54] Countering myths about arthritis and applying available interventions can help reduce the impact of this health problem. (See Focus Area 6. Disability and Secondary Conditions.)
Interventions for osteoporosis and fractures can be designed to prevent the development of the disease, reduce further bone loss after the occurrence of the disease, and lessen the risk of fractures. Opportunities for primary prevention occur throughout the lifespan and include programs to promote exercise, avoid smoking, reduce excessive alcohol consumption, and improve nutrition, particularly the amount of calcium and vitamin D in the diet. (See Focus Area 19. Nutrition and Overweight.) These approaches may be important in achieving a high peak bone mass during adolescence to delay the onset of osteoporosis as bone mass declines with age. The approaches also may reduce the rate of bone loss later in life.
Women need to be particularly concerned about bone loss occurring at the time of menopause, when bone can be lost at the rate of 2 to 4 percent per year. Women should be counseled on methods to minimize their bone loss. Evidence indicates that older persons, even those who have had a fracture, can benefit from treatment to prevent further bone loss or restore some lost bone to decrease the risk of subsequent fractures.[55]
A wide range of interventions prevent or reduce low back problems. These interventions may include activities designed to reduce the physical demands of work activities by redesigning the task or to address the individual’s specific needs, such as strength or endurance training or counseling for nutrition and lifestyle changes. Ergonomic interventions that are directed at changing the job or work environment have proved effective in reducing risk of occupational low back pain. (See Focus Area 20. Occupational Safety and Health.) Thus, it is reasonable to assume that ergonomic approaches would be effective in preventing chronic LBP as well. Even in a nonwork environment, the physical demands of an activity can be reduced by using ergonomic principles. Interventions involving training in proper lifting techniques, physical conditioning, and weight loss have been investigated in programmatically oriented studies. These have shown that workplace interventions may have an effect on low back disorders.[56] The overall benefits of exercise, nutrition, and lifestyle changes on an individual’s health and well-being would certainly justify efforts in this area. Also, interventions directed at improving strength and endurance may have an important impact on reducing activity limitations due to chronic LBP.
Because national data systems will not be available in the first half of the decade for tracking progress, four subjects of interest concerning arthritis and osteoporosis are not covered in this focus area’s objectives. Representing a research and data collection agenda for the coming decade, the topics involve appropriate management, patient education, provider counseling, and bone fracture prevention. The first addresses persons with systemic rheumatic disease who receive an early specific diagnosis and appropriate management plan. The second topic concerns hospitals, managed care organizations, and large group practices that provide effective, evidence-based arthritis education (including information about community and self-help resources) for patients to use as an integral part of the management of their condition. The third topic concerns health care provider counseling for persons at risk for or who have arthritis. Women aged 65 years and older who are eligible under Medicare criteria to have an initial bone density measurement are the focus of the fourth topic about bone fracture prevention.
(A listing of abbreviations and acronyms used in this publication appears in Appendix H.)
Activity limitations: Problems in a person’s performance of everyday functions such as communication, self-care, mobility, learning, and behavior.
Arthritis: Shorthand for arthritis and other rheumatic conditions.
Arthritis and other rheumatic conditions: More than 100 conditions (or diseases or problems) that primarily affect the joints, muscles, fascia, tendons, bursa, ligaments, and other connective tissues of the body.
Bone mineral density (BMD): Measurement used to determine the presence of osteoporosis.
Chronic back conditions: Low back pain and other conditions affecting only the back.
Chronic joint symptoms: Pain, aching, stiffness, or swelling in or around a joint that was present on most days for at least 1 month in the past 12 months.
Disability: General term used to represent the interactions between individuals with a health condition and barriers in their environment. The term disability is operationalized as self-reported activity limitations or use of assistive devices or equipment related to an activity limitation.
Musculoskeletal conditions: Problems that affect the skeleton, joints, muscles, and connective tissues of the body.
Osteoarthritis: A slowly progressive, degenerative joint disease that results from the breakdown of cartilage and leads to pain and stiffness; usually affects the knees, hips, and hands; the most common form of arthritis.
Osteopenia: A condition similar to osteoporosis (see below) except the reduction in bone mass is not as severe.
Osteoporosis: Bone disease characterized by a reduction of bone mass and a deterioration of the microarchitecture of the bone leading to bone fragility.
Personal care activities: Eating, bathing, dressing, or getting around inside the home, including getting in or out of bed or chairs and using the toilet (including getting to the toilet).
Rheumatoid arthritis: A chronic, inflammatory disease of the body that produces its most prominent manifestations in joints, often leading to joint pain, stiffness, and deformity.
Work disability: Limited in the amount or kind of work; unable to work.
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