Oct. 18, 2021 — Conditions like arthritis and gout that cause stiff and painful joints affect almost 1 in 4 adults in the United States, a new federal report says, and the numbers are growing as the population gets older. As a result, many of these people — nearly 44% — are physically limited and can’t fully take part in activities like hobbies or housework.

Researchers also report that people with disabilities and those who are poorer are most vulnerable to these disorders.

The findings, based on estimates from 2016 to 2018, “fall right in line with the trends that have been observed in arthritis over the past 20 years,” says Boston University School of Public Health biostatistician Michael LaValley, PhD. “The prevalence is increasing.”

The CDC report, published Oct. 8, is based on in-person interviews done with tens of thousands of U.S adults as part of the National Health Interview Survey. Researchers estimate that 24% of adults in the U.S. — or about 58.5 million people — have been diagnosed with general arthritis, rheumatoid arthritis, gout, lupus, or fibromyalgia. The number has increased by 4.1 million from the CDC’s previous set of estimates that covered the years 2013-2015.

“The degree of limitations can be different from person to person,” Theis says. “For example, one respondent’s knee pain from arthritis could limit them in their job stocking groceries. Another respondent’s hand pain from arthritis could limit them in playing tennis with friends. There might be respondents with hip pain or ankle stiffness from arthritis that limits how many hours they can sit or stand.”

The limits can be especially grueling in some cases, since the people who have them “might have reached the point where they are making decisions about which days to shop for groceries, do housework, run errands, or even interact with friends and family based on their degree of pain and fatigue from arthritis,” she says.

Several groups of people are more likely to have limits on activities, including those who are poor and those with “serious psychological distress,” according to the report.

As for specific conditions, how often people have osteoarthritis, which happens when bones deteriorate, may be influenced by the aging of the American population, the rise of obesity, and couch-potato behavior, LaValley says.

“There is also some thinking that there may be environmental factors increasing the risk for some types of arthritis, but nothing conclusive,” he says “There also may be more attention paid to arthritic conditions, leading to more people being diagnosed or even just suspecting that they have arthritis.”

Why might poverty be related to arthritis? “There almost certainly are occupational exposures that put people at risk of osteoarthritis — having to kneel, stoop, and lift heavy things — or other musculoskeletal conditions like lower back pain,” LaValley says. “These exposures are most likely in jobs that would predominantly go to people with few other options due to lower levels of income and education. People in these jobs would also be likely to be under financial stresses that lead to increased psychological distress and less time to take care of their health.”

The new CDC report suggests there are many ways to combat arthritis, including education about treatment and prevention plus more focus on improving society’s inequalities.