People with psoriatic arthritis can be symptomatic for years before the condition is diagnosed, according to two recent reports.
There are no reliable diagnostic biomarkers, and sometimes patients have vague symptoms with only minimal physical findings, which makes it hard for physicians to recognize the problem and refer to rheumatology.
In the meantime, the longer it takes to diagnose psoriatic arthritis (PsA) and treat it properly, the worse off patients are when it’s finally caught. They “present with a greater rate of clinical progression and worse physical function, compared with patients with an undelayed diagnosis,” and more radiographic joint damage, according to investigators led by rheumatologist, an associate professor of medicine at the University of Pennsylvania, Philadelphia.
Dr. Ogdie’s study in
Delay associated with misdiagnosis
Dr. Ogdie’s team surveyed 203 adults with PsA – average age of 52 years, mostly white, and over 80% women – about their diagnosis history. The time between seeking medical attention for PsA-related symptoms and receiving a diagnosis was less than 6 months for 69 participants, 6 months to 4 years for 68, and 5 years or more for 66.
Typical symptoms, like joint pain, swollen joints, reduced range of motion, and dactylitis, were associated with quicker diagnosis. Turning early to dermatologists and rheumatologists – instead of general practitioners, orthopedics, chiropractors, and others – sped diagnosis, as well. People diagnosed within 6 months also tended to be slightly older, were less likely to be disabled or unemployed, have more education, and were more likely to make $100,000 per year or more.
Vaguer symptoms, such as stiffness, fatigue, and enthesitis-associated foot pain, delayed diagnosis. The longer PsA went unrecognized, the more likely people were to be misdiagnosed with osteoarthritis, psychosomatic disorders, and other problems.
“Increased recognition of heterogeneous symptoms associated with PsA, as well as understanding existing diagnostic barriers, may lead to prompt diagnosis and initiation of appropriate treatment that may improve outcomes,” the investigators concluded.
A prodromal phase
In the, investigators led by codirector of the cardio-rheumatology program at Women’s College Hospital, Toronto, used health records and databases to compare primary care histories of 462 Canadian PsA patients in the 5 years before they were diagnosed with 2,310 age- and sex-matched controls without PsA and treated by the same family physicians. The mean age in the study was 54 years, and just over half the subjects were women. Socioeconomic status and rurality were similar between the two groups.
The mean time from the initial primary care visit for a musculoskeletal complaint to rheumatology referral was 513 days among PsA patients, “which was substantially longer than for other inflammatory arthritic conditions, such as rheumatoid arthritis,” Dr. Eder and associates noted.
PsA patients were more than twice as likely to visit primary care for nonspecific musculoskeletal issues in the year before their diagnosis, and more likely in the 5 years prior. The odds of visits to musculoskeletal specialists, joint injections, joint imaging, and ED visits, was also higher as early as 5 years before PsA recognition, and hinted at the impending diagnosis.
“Our study characterized a prediagnosis period in PsA and supports the notion that a prodromal PsA phase occurs in a significant proportion of patients. ... This pattern reveals some of the underlying causes of diagnosis delays of PsA and highlights the need for diagnostic strategies and novel reliable biomarkers to aid in early diagnosis of PsA,” the investigators concluded.
Dr. Ogdie and colleagues suggested that community case searches, public awareness programs, patient education, and referral guidelines for primary care providers might help. They also suggested greater use of validated screening tools, such as the, in primary care.
Dr. Eder had no disclosures, and her study was funded by the Canadian Rheumatology Association. Dr. Ogdie’s study was funded by Novartis, maker of secukinumab (Cosentyx), which is indicated for PsA. She is a consultant for Novartis and has received grant support from the company. One author is an employee.
SOURCES: Ogdie A et al. BMC Rheumatol. 2020 Jan 10. ; Eder L et al. Arthritis Care Res. 2020 Jan 21.