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.