Patient preferences regarding biologic treatment of their psoriatic arthritis (PsA) are understandably heterogenous but an oral route of administration is one of the big pluses, an Australian study shows.
A discrete choice experiment (DCE), presented as an online survey of 164 patients from three rheumatology centres in Sydney, found oral treatments were much preferred over subcutaneous injections of any frequency, or intravenous infusions.
Overall, patients also prioritised the avoidance of rare but severe side effects and the ability to work or participate in normal daily activities.
Clinical measures of treatment efficacy such as improvement in enthesitis pain, improvement in psoriasis, increasing chance of remission and improvement in joint pain, were less important to most patients.
The study, published in Arthritis Care & Research, found that people fitted into two groups on the basis of their patterns of preferences.
Those who prioritised the avoidance of severe complications of treatment and ability to work and have normal activity typically had less experience or knowledge of biologics, a shorter disease duration and less pain. They were also older, comprised more female patients, and had a higher household income.
Patients who prioritised the oral route of treatment were younger, had a longer disease duration, more experience of biologic treatment, higher perceived knowledge of medications and more pain.
“These participants were more likely to be comfortable with the most frequently used subcutaneous methods of treatment delivery suggestive of some experiential tolerance to subcutaneous medications,” the study authors said.
The investigators, led by Dr Daniel Sumpton from Concord Hospital, said it was unclear why participants with higher income were more likely to be in the group prioritising return to work – unless it was a desire to protect their income.
“There may also be differences in health literacy between different income classes driving differences in preferences between these two groups,” they said.
The finding that work was so important to many people, may also have implications for clinical trials in psoriatic arthritis, the study authors suggested.
“Our study strengthens the conclusions from OMERACT that the PSAID [Psoriatic Arthritis Impact of Disease measure] should be included in clinical trials of psoriatic arthritis to determine the efficacy of biologics on the ability to undertake work and leisure activities,” they wrote.
The findings also highlighted an apparent discrepancy between the outcomes of biologic medications most important to patients and the clinical parameters used by rheumatologists.
“Our findings also reflect similar DCE studies of preferences for biologics in psoriasis, showing that patients prefer avoiding severe adverse events above the value they place on treatment efficacy,” they said.
Therefore, shared decision-making around treatment options was essential, they added.
“Our study reinforces the need for rheumatologists to discuss the functional and social domains associated with treatment and the risk of infection and severe adverse events when making treatment decisions about biologic medications with their patients.”