A population-based cohort study using the Rochester Epidemiology Project assessed the relationship between multimorbidity and the development of psoriatic arthritis (PsA) in patients with psoriasis. While newly diagnosed (incident) patients with psoriasis showed no significant difference in multimorbidity compared with matched controls, those with longstanding (prevalent) psoriasis had significantly higher rates of multiple chronic conditions. Over a median follow-up of 13.3 years, approximately 3% of patients with psoriasis developed PsA. The presence of two or more chronic conditions at the time of psoriasis diagnosis was associated with a nearly threefold increased risk of developing PsA, especially among those with musculoskeletal or psychiatric comorbidities.

These findings suggest that patients with psoriasis may develop multimorbidity more rapidly than the general population, and that the presence of multiple chronic conditions at diagnosis could serve as an early signal for heightened PsA risk. Notably, multimorbidity was linked to PsA development regardless of psoriasis severity, reinforcing the need for vigilant monitoring across all patients psoriasis. The study highlights the importance of recognizing and managing comorbidities—particularly nonspecific musculoskeletal symptoms and mood disorders—as potential indicators of PsA risk, underscoring the need for integrated, proactive care strategies.

Reference: Karmacharya P, Chakradhar R, Hulshizer CA, et al. Multimorbidity in psoriasis as a risk factor for psoriatic arthritis: a population-based study. Rheumatology (Oxford). 2025 Apr 1;64(4):2199-2203. doi: 10.1093/rheumatology/keae040. PMID: 38291896; PMCID: PMC11962958.