Two CDC reports illustrate the state of arthritis in the U.S.

The prevalence of arthritis and arthritis-attributable activity limitations (AAAL) continued to rise from 2016-2018 among U.S. adults—but some of those affected also reported engaging in physical activity, especially walking, which may improve their long-term health outcomes.

Over the past two decades, arthritis has become the most frequently reported cause of disability among U.S. adults, leading to more than $300 billion in annual costs and increasing levels of anxiety and depression. What’s more, despite the known benefits of physical activity on long-term health, only 36.2% of adults with arthritis meet aerobic physical activity guidelines.

Now, a pair of CDC reports published in the Morbidity and Mortality Weekly Report have illustrated the state of arthritis in the U.S., and their findings suggest that, while incidence of the condition has continued to rise, the chronic condition may not preclude walking and other mild physical activites that could potentially attenuate pain and disability associated with the disease.

The first report, which analyzed data from the National Health Interview Survey (NHIS) for 2016-2018, found that the number of U.S. adults with arthritis continued to increase compared to 2013-2015—while incidence of AAAL seems to have accelerated.

“Annualized estimates from 2016–2018 indicate that the number of U.S. adults with arthritis (58.5 million) and AAAL (25.7 million) increased compared with 2013–2015 estimates (54.4 million and 23.7 million, respectively) ,” Kristina A. Theis, PhD, and colleagues from the CDC found. “Arthritis prevalence continues to align closely with projections, but the percentage of the U.S. population reporting AAAL during 2016-2018 (10.4%) had already exactly met the 2020 projection (10.4%), continuing a previously observed acceleration in the rise of AAAL.”

Notably, Theis and colleagues found that the prevalence of both arthritis and AAAL was “higher in sub-groups representing adults with fewer economic opportunities (i.e., lower education, unable to work or disabled, and lower income-to-poverty ratios), poorer overall health (i.e., higher BMI, less physical activity, more serious psychological distress, and worse self-rated health), and more physical limitations (i.e., joint symptoms in the past 30 days and ADL and IADL disabilities).”

Among the findings:

  • Arthritis prevalence hit 50.4% among adults 65 years of age and older; 52.3% among adults who were unable to work or disabled; 51.2% among adults with fair/poor self-related health; 52.2% among those with joint symptoms in the past 30 days; 54.8% among those with activities of daily living (ADL) disability; and 55.9% among those with instrumental ADL (IADL) disability.
  • Among those with arthritis, “unadjusted prevalence of AAAL exceeded 50% in several groups, including adults with joint symptoms in the past 30 days (51.6%), adults who were unable to work or disabled (54.7%), adults of other/multiple races (54.5%) or non-Hispanic American Indian or Alaska Natives (60.7%), adults with low income (53.3%) or poor/near poor income-to-poverty ratios (63.3%), or with moderate psycho-logical distress (59.5%).”
  • AAAL was reported by the majority of adults with arthritis and ADL disability (82.6%); IADL disability (80.4%); serious psychological distress (76.3%); and fair/poor self-related health (72.6%).

“Because population aging and other contributing factors (e.g., obesity) are expected to sustain these trends, public health, medical, and senior and other service systems face substantial challenges in addressing the needs of adults with arthritis, who already account for nearly one quarter of U.S. adults,” Theis and colleagues wrote. “A coordinated approach of expanding intervention implementation among adults already limited by arthritis while mitigating future negative arthritis effects by creating ’social, physical, and economic environments that promote attaining the full potential for health and well-being,’ could help improve quality of life and limit the personal and societal impacts of arthritis.”

Facilitating physical activity among these patients can potentially offer a major impact for long-term outcomes for patients with arthritis, improving physical function and reducing pain and fall risk, Dana Guglielmo, MPH, and colleagues from the CDC explained in a second report. However, there is little research on which activities patients with arthritis actually engage in.

To close this knowledge gap, Guglielmo and colleagues analyzed data from the Behavioral Risk Factor Surveillance System (BRFSS) for 2019 to examine the most common non-work physical activities among adults ages 18 years and older with arthritis who reported any physical activity within the last month.

“In 2019, 67.2% of adults with arthritis engaged in non-work–related physical activity in the past month; walking was the most commonly reported activity (70.8%), followed by gardening (13.3%), and weightlifting (7.3%),” they found. “The percentage reporting walking was lowest among those 18–44 years (63.7%). The age-adjusted prevalence of walking was higher among women (76.0%) than among men (63.9%), higher among non-Hispanic Black (75.4%) adults than among non-Hispanic White (70.0%) and non-Hispanic other/multiple race adults (68.3%), and higher among those who were unable to work or disabled (79.0%) compared with those adults with other employment statuses (67.7%–74.8%).”

Interestingly, despite arthritis being a substantial cause of pain and disability, the age-adjusted percentage of adults with arthritis who reported walking “increased with increasing joint pain severity and body mass index,” which may indicate that “the presence of pain might not automatically preclude walking, other physical activities, and their associated benefits.”

The study authors also pointed out that the type of physical activity reported among patients with arthritis varied substantially by income level—for example, those with lower socioeconomic status were more likely to walk and less likely to lift weights compared to higer income patients. Walking is already an ideal activity for adults with arthritis, Guglielmo and colleagues noted, because it is “Safe, convenient, low-impact, and adaptable to individual fitness level,” but this finding suggests that it may also be ideal for those with limited income.

“To promote physical activity among adults with arthritis, health care providers can offer advice or counseling for walking or referrals to low-cost, evidence-based physical activity programs,” the study authors concluded. “These programs might help adults with arthritis overcome common barriers to physical activity, including cost, lack of instructions about preventing risk for injury while exercising, and fear of arthritis worsening. Communities can address physical environment barriers to walking by providing safe and supportive infrastructures such as sidewalks, benches, and green spaces. Promoting engagement in physical activity among adults with arthritis can reduce their risk for chronic health conditions and improve their mental health and quality of life.”

Study limitations for the report by Theis and colleagues include potential recall and social desirability bias due to self-reporting and an inability to establish a causal relationship between the study outcomes (arthritis and AAAL) and the characteristics analyzed. Limitations reported by Guglielmo and colleagues include self-reporting; low state-specific response rates; specific activity participation may be underestimated as participants only reported their to most frequent activities and excluded work-time activities; data was only available for 49 states; and the study estimated reported activities undertaken, which may not actually reflect preferred activities among this population.

  1. In the U.S., arthritis incidence increased at the predicted rate in 2016-2018 compared to 2013-2015, while incidence rates for arthritis-attributable activity limitation (AAAL) surpassed projections, suggesting an acceleration in the rate of arthritis-related disability.

  2. Of arthritis patients who reported any physical activity in the preceeding month, 70.8% engaged in walking, and walking prevalence increased with increasing joint pain severity.

John McKenna, Associate Editor, BreakingMED™

The study authors had no relevant relationships to disclose.

Cat ID: 68

Topic ID: 90,68,408,730,192,68,925

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