Economic and Comorbidity Burden Among Moderate‐to‐Severe Psoriasis Patients with Comorbid Psoriatic Arthritis

OBJECTIVE To compare the prevalence of comorbidities, health care utilization, and costs between moderate-to-severe psoriasis (PsO) patients with comorbid psoriatic arthritis (PsA) and matched controls. METHODS Adults ages 18-64 years with concomitant diagnoses of PsO and PsA (PsO+PsA) were identified in the OptumHealth Reporting and Insights claims database between January 2007 and March 2012. Moderate-to-severe PsO was defined based on the use of at least one systemic or phototherapy during the 12-month study period after the index date (randomly selected date after the first PsO diagnosis). Control patients without PsO and PsA were demographically matched 1:1 with PsO+PsA patients. Multivariate regressions were employed to examine PsO/PsA-related comorbidities, medications, health care utilization, and costs between PsO+PsA patients and controls, adjusting for demographics, index year, insurance type, and non-PsO/PsA-related comorbidities. RESULTS Among 1,230 matched pairs of PsO+PsA patients and controls, PsO+PsA patients had significantly more PsO/PsA-related comorbidities, with the top 3 most common in both groups being hypertension (35.8% versus 23.5%), hyperlipidemia (34.6% versus 28.5%), and diabetes mellitus (15.9% versus 10.0%). Compared with controls, PsO+PsA patients had a higher number of distinct prescriptions filled (incidence rate ratio 2.3, P < 0.05); were more likely to have inpatient admissions (odds ratio [OR] 1.6), emergency room visits (OR 1.3), and outpatient visits (OR 62.7) (all P < 0.05); and incurred significantly higher total, pharmacy, and medical costs (adjusted annual cost differences per patient $23,160, $17,696, and $5,077, respectively; all P < 0.01). CONCLUSION Compared with matched PsO- and PsA-free controls, moderate-to-severe PsO patients with comorbid PsA had higher comorbidity and health care utilization and costs.