For 12 months, Meera Sheffrin’s focus was entirely on keeping her 80-year-old patient’s moderate dementia and heart issues stable. But medical complexity can create blind spots. Without prior records or complaints of joint stiffness, the geriatrician had no idea the woman also had rheumatoid arthritis — until the patient’s daughter mentioned her mother’s aching hands.

Looking closely, Sheffrin, MD, a clinical associate professor of medicine at the Stanford University School of Medicine in Palo Alto, California, saw the unmistakable hand deformities she previously overlooked.

“I missed that she even had arthritis because I was focused on her cardiac and cognitive issues,” she said. An x-ray quickly confirmed the diagnosis.

Sheffrin prescribed hydroxychloroquine and looped in a rheumatologist, who cleared the primary care team to handle the ongoing therapy themselves.

About 1 in 4 adults in the US have some form of arthritis, according to the CDC. Inflammatory arthritis, including rheumatoid, often goes undiagnosed for more than a year because aging and comorbidities can mask the condition in older patients. A recent clinical review published in JAMA Internal Medicine highlighted how primary care clinicians can catch and treat the condition.

“There is no question we are seeing more and more older adults in our clinics, most of whom have joint pain,” said Una Makris, MD, a clinical professor of rheumatology and geriatrics at the University of California, San Diego School of Medicine, who helped write the review. “Sometimes it can be challenging to figure out what is driving the pain.”

Patients, too, may attribute their symptoms to natural changes associated with getting older, said Sheffrin, who was not involved with the review.

“People will come in after months of pain and finally mention it,” she said. “They didn’t before because they were trying a bunch of other stuff –– orthotics, a new mattress –– because they didn’t suspect arthritis.”

Not Osteoarthritis

While osteoarthritis is the most common cause of joint pain, stiffness, and swelling, primary care clinicians should first rule out inflammatory arthritis, which includes spondyloarthritis and crystal arthropathies, Sheffrin said.

Osteoarthritis and inflammatory arthritis cause similar discomfort, and both can affect joints in the knees, back, hands, and feet.

However, the differences between the two “are usually pretty distinct,” said Nancy Lane, MD, a rheumatologist at UC Davis Health in Sacramento, California, who was not involved with the review.

“Osteoarthritis gives you pain in the joint for a few minutes when you get up in the morning and may ache a little bit at night after you’ve used your joints all day,” Lane said.

Inflammatory arthritis, meanwhile, causes prolonged stiffness often presenting at waking and can last up to 3 hours, Lane said. Swelling typically affects more than one joint, such as knuckles and metacarpal joints of the hand and toes, areas usually not affected by osteoarthritis, Lane said.

Inflammatory pain usually improves with movement, while activity generally makes osteoarthritis worse. Osteoarthritic pain often occurs after an accident and is persistent, the authors wrote, while the inflammatory condition can be acute or episodic and can occur at night.

Asking patients questions about timing, length, and location of pain is the first step in making an accurate diagnosis, said Raymond Yung, MD, director of the Institute of Gerontology at Michigan Medicine in Ann Arbor, Michigan.

If a patient usually feels fine when they wake up, but when they walk down the stairs their knees begin to ache, that could be a good indication of noninflammatory or mechanical arthritis, Yung said, who was not involved with the review.

A patient can also develop two types of arthritis, Yung said. He recently received a referral for a patient with osteoarthritis who developed sudden joint pain and had trouble scaling stairs. For about a year, the patient had taken pain medication and attended regular physical therapy sessions, treatment ordered by his primary care clinician. When neither had worked, the clinician referred him to rheumatology, where Yung discovered the man also had inflammatory arthritis.

“That is a really typical scenario that I see that causes a delay in patients being referred to me as a specialist,” Yung said. “Oftentimes the assumption that this is related to either age or osteoarthritis.”

Normal Aging Could Mask Symptoms

Diagnosing inflammatory arthritis in patients in their seventies or eighties can be challenging, as initial signs often mimic normal age-related changes, Sheffrin said.

“Older adults tend to slow down, they will say, ‘I’m fatigued or not moving enough,’ and it’s very nonspecific,” she said. “You have to get more information on that –– is it because you’re out of breath? Is there pain in your knees when you stand up?”

Patients with the condition may also experience decreased appetite, weight loss, and unusual fatigue –– all symptoms that may be a normal part of aging. But the symptoms should not be ignored, Yung said.

“Agism, conscious or unconscious, could cause us to not treat older folks optimally,” he said. “Take peoples’ concerns seriously and don’t assume any symptoms are just because of a person’s age.”

Sheffrin said primary care clinicians can gather information about their patients’ joints with a simple x-ray. How the erosion shows up on imaging –– usually symmetrical bone loss for immune-related arthritis or the thinning of gaps between bones in those with osteoarthritis –– can be smoking guns. An x-ray can also rule out other suspected conditions such as polymyalgia rheumatica, Sheffrin said.

Serogenerative Makes Some Tests Obsolete

A 78-year-old patient experiencing a sudden onset of morning stiffness and unusual fatigue was recently referred by her primary care physician (PCP) to geriatric rheumatologist Makris.

The patient could not do a full shoulder rotation without triggering sharp pain. Her fingers and knuckles were visibly swollen and tender. Her grip strength was weak. Makris suspected rheumatoid arthritis.

Blood tests revealed the woman had elevated levels of C-reactive protein, but she was negative for both rheumatoid factor and anti-cyclic citrullinated peptide, two tests used to diagnose rheumatoid arthritis. An x-ray revealed small areas of bone damage around the woman’s middle knuckles, tipping Makris off to seronegative rheumatoid arthritis.

The condition presents with the same classic symptoms as rheumatoid arthritis, but without rheumatoid factor and anti-cyclic citrullinated peptide. Relying solely on autoantibody tests will cause clinicians to miss seronegative rheumatoid arthritis, which account for up to 30% of cases.

“It is often a diagnostic puzzle,” Sheffrin said. “Usually, PCPs are aware that something isn’t quite right, but it is a little hard to figure out because you order tests and those come back negative. That’s usually when they refer the patient to a specialist.”

While primary care clinicians can prescribe some medications, biologics usually need to be prescribed by a rheumatologist to comply with health insurers policies, Yung said. But waitlists for these specialists can last for months.

PCPs can support patients with medications that can temporarily help them feel better.

“A lot of PCPs are comfortable prescribing your first line of treatment, maybe steroids to get inflammation down,” Sheffrin said.

None of the experts reported related disclosures.

Kaitlin Sullivan is a journalist living in Colorado.