ROME – Anti–tumor necrosis factor agents have a slight edge over conventional disease-modifying antirheumatic drugs when it comes to helping psoriatic arthritis patients who are having work issues, according to a large British observational study presented at the European Congress of Rheumatology.
Among 236 of 400 subjects working at baseline, presenteeism improved from 30% to 10% and productivity loss improved from 45% to 10% among patients who started taking anti-TNF (anti-tumor necrosis factor) agents. Gains were more modest when patients were started on DMARDs, with presenteeism improving from 30% to 20% and productivity loss from 40% to 25%. The difference in change of presenteeism between the two treatment groups became statistically significant at 2 weeks and remained so at 24 weeks.
“Work disability is a continuum,” said the presenting author, Dr. William Tillett of the Royal National Hospital for Rheumatic Diseases in Bath (England). It starts with the normal situation then graduates from presenteeism, where the individual is sick but still attends the workplace, to absenteeism, where the individual is sick and no longer attends the place of work, and eventual unemployment, he explained. “This study suggests that work disability is reversible in the real-world setting,” he added.
The study is from the Long-term Outcomes in Psoriatic ArthritiS (LOPAS II) working group, a 2-year, multicenter, prospective, observational cohort study of work disability in psoriatic arthritis. The group has previously reported that unemployment in psoriatic arthritis is associated with older age, disease duration of 2-5 years, and worse physical function, but that employer awareness and helpfulness enabled patients to stay on the job. Higher levels of global and joint-specific disease activity and worse physical function were associated with greater levels of reporting to work sick (presenteeism) and productivity loss (Rheumatology 2015;54:157-62).
The latest study by Dr. Tillett and his team is a follow-up to see how treatment affects work performance. At baseline, before treatment with anti-TNF or DMARDs, the LOPAS II team of investigators found that 164 (41%) of their 400 subjects were unemployed. Unemployed patients tended to be older (median of 59 years vs. 49 years) and to have worse physical function (a median score of 1.4 on the Health Assessment Questionnaire vs. 1.0). Subsequent treatment with anti-TNFs or DMARDs didn’t change overall employment levels.
Patients who started on anti-TNFs tended to have longer disease duration (median of 11 vs. 5 years) and a greater median number of tender (16 vs. 11) and swollen (7 vs. 5) joints, but otherwise there were no significant differences in demographic or clinical measures between the two treatment groups.
Median scores on the Disease Activity Index for Psoriatic Arthritis (DAPSA) improved over 24 weeks from 53 to 14 among anti-TNF patients, which is considered a good response, but only improved from 39 to 30 in the DMARD group, which is considered a poor response. All of the findings were statistically significant.
The results revealed a “surprisingly poor clinical response to synthetic DMARDs on clinical outcomes … as opposed to good response amongst patients commenced on TNF inhibitors,” Dr. Tillett said in an interview. The improvement in work disability and disease activity seen also was greater and more rapid among those who started on anti-TNF rather than synthetic DMARD.
Dr. Tillett reported receiving grant/research support from AbbVie and speaker or advisory board fees from UCB, Pfizer, and AbbVie. The other authors said they have no disclosures.