Paradoxical Effects of Depression on Psoriatic Arthritis Outcomes in a Combined Psoriasis-Psoriatic Arthritis Center

Abstract

Backgroud: Psoriatic arthritis (PsA) is a chronic, inflammatory arthritis that, when left untreated, can lead to erosions, deformities and decrease in quality of life. PsA is known to be associated with multiple comorbidities, including cardiovascular, metabolic and mental health syndromes, all of which can increase its overall morbidity and mortality.

Objective: To characterize a cohort of patients with PsA and understand the impact of depression on PsA outcome measures.

Methods: 527 consecutive patients with PsA were enrolled in an observational, longitudinal registry that followed them prospectively at standard of care visits. Demographics, medical history, medication use, and clinical exam were all recorded.

Results: Depression was reported in 22.8% of the population, anxiety in 18%, and attention deficit hyperactivity disorder in 4%. Depression was more common in female participants (P < .001). At baseline, individuals with PsA and concomitant depression had similar tender and swollen joint counts and RAPID3 compared to those without depression, and had lower body surface area affected by psoriasis (P = .04). At year one, all patients had improvement in clinical outcomes. However, patients with depression had a significantly higher tender joint count compared to those without depression (P = .001), despite similar swollen joint count and body surface area.

Conclusion: In patients with depression, there is a discrepancy between improvement in physician assessed measures and patient reported outcomes. These observations underscore the importance of addressing depression and psychological distress as part of PsA treatment outcomes and points towards the need to address residual pain through co-adjuvant approaches.

Keywords: depression; depression < comorbidity < psoriasis; pain; patient-reported outcome < psoriasis; psoriasis; psoriatic arthritis; treatment outcomes < treatment < psoriasis.

Figure 1.

Observed mean PsA outcomes at baseline, year 1, and year 2. Red represents patients with depression, blue represents patients without depression. *P < .05.

Figure 2.

Model predicted means with 95% confidence bands (A), and predicted ratio ratios and estimated differences (B), adjusting for age, sex, race, comorbidities, and medication use.