Psoriatic arthritis and the need for better care

Around 20-30% of people living with psoriasis develop psoriatic arthritis (PsA). Often the diagnosis of psoriasis precedes that of PsA by a decade. Nevertheless, PsA is often underdiagnosed, potentially leading to serious consequences: untreated PsA can cause persistent inflammation and joint damage and can lead to permanent functional impairment. It has been shown that a delay of 6 months between the onset of first symptoms and the consultation with a rheumatologist can have serious impact on long-term physical function (1). Therefore, it is extremely important that people living with psoriasis talk about the symptoms affecting their joints, and that both dermatologists and primary care doctors investigate the possible onset of PsA during consultations.

Despite the clear link between psoriasis and psoriatic arthritis, the journey towards a diagnosis of PsA is not simple. In a recent article, scientists from university of Pennsylvania collected the experience of people living with PsA on their journey to being properly diagnosed (2). The data show that those who waited longer times before diagnosis (at least 5 years) experienced less recognized PsA symptoms such as fatigue and back pain, whereas people diagnosed in a short time period (less than 6 months) presented more typical symptoms such as swollen and painful joints as well as reduced motility. Sadly, the more common reason for misdiagnosis for people that waited more than 5 years to get a PsA diagnosis was a lack of belief that the symptoms were real (“it’s all in my head”) (2). Not being taken seriously by the doctors adds up to the already heavy burden on mental health in people living with PsA: one in three people living with PsA suffer from anxiety, and one in five people suffer from depression. Both mental health conditions are higher in people living with PsA compared to people living with psoriasis only (3). Mental health impairment and PsA are linked in multiple ways:

• Depression increases the risk of developing PsA in people living with psoriasis (4)
• The diagnosis of a life-long disease, the symptoms of PsA impacting social and working life, and the side effects of medications can cause depression
• Depression lowers the pain threshold (5), thus the disease becomes more painful
• People affected by depression are less likely to take their medications

Primary care doctors and dermatologists have an important role in recognizing the onset of PsA and refer patients to the rheumatologist. Moreover, they can be attentive to the wellbeing of their patients and reduce the risk that people living with PsA develop depression.

There are good examples of care settings for people living with PsA. Combined dermatology-rheumatology clinics are available in UK and North America (6), and both patients and doctors positively rate this type of clinics. The addition of a dermatology nurse in supporting rheumatologists is another way to ensure that the best possible care is provided to the patients, while being more cost-effective for health systems (7).

Many of IFPA member organizations work to spread awareness of PsA, and help close the gap between the fields of dermatology and rheumatology. PsorPhil (Philippines) organizes Skin and Bone clinics. AEPSO (Argentina) set up a mobile clinic with equipment for the detection of PsA. CAPP (Canada) made a website with information for patients (myskinandbone.ca). Almost all IFPA member associations create informational material or organize symposia on PsA.

IFPA’s mission is to achieve a world free from suffering from psoriasis and PsA, so PsA has always been part of the IFPA agenda. Our plan is to bring PsA into focus even more.

References and further reading

1.Haroon et al. Diagnostic delay of more than 6 months contributes to poor radiographic and functional outcome in psoriatic arthritis. Ann Rheum Dis 2015; 74 (6), 1045-50. https://ard.bmj.com/content/74...

2.Ogdie et al. Patient perspectives on the pathway to psoriatic arthritis diagnosis: results from a web-based survey of patients in the United States. BMC Rheumatol 2020; 4, 2. https://bmcrheumatol.biomedcen...

3.Zhao et al. Systematic Review of Mental Health Comorbidities in Psoriatic Arthritis. Clin Rheumatol 2020; 39 (1), 217-225. https://link.springer.com/article/10.1007...

4.Lewinson et al. Depression is associated with an increased risk of psoriatic arthritis among patients with psoriasis: a population-based study. J Invest Dermatol 2017; 137 (4), 828-835. https://www.jidonline.org/arti...

5.Bagnato et al. Pain threshold and intensity in rheumatic patients: correlations with the Hamilton Depression Rating scale. Clin Rheumatol 2015; 34 (3), 555-61. https://link.springer.com/arti...

6.Okhovat et al. Psoriasis and Psoriatic Arthritis Clinics Multicenter Advancement Network Consortium (PPACMAN) Survey: Benefits and Challenges of Combined Rheumatology-dermatology Clinics. J Rheumatol 2017; 44 (5), 693-694. http://www.jrheum.org/content/44/...

7.Mai et al. Nurse-led Care Versus Physician-Led Care in the Management of Rheumatoid Arthritis and Psoriatic Arthritis (StaerkeR): Study Protocol for a Multi-Center Randomized Controlled Trial. Trials 2019; 20 (1), 793. https://www.ncbi.nlm.nih.gov/p...