Background Psoriatic arthritis (PsA) is often presented with psoriasis (PsO). However, the severity of PsO among PsA patients varies, which may affect the comorbidity burden in this population.
Objectives This study aimed to assess the comorbidity burden and medication use between PsA patients with moderate-to-severe PsO vs. those with minimal skin PsO.
Methods Adults (18–64 years) with ≥2 claims for PsA (ICD-9-CM: 696.0) that were ≥30 days apart were selected from the Truven Health MarketScan claims database (data cut period 07/2009–06/2014). The index date was a randomly selected date after the first PsA claim. All patients were required to have ≥12-month continuous eligibility before (baseline period) and after (study period) the index date. Patients in the PsA+moderate-to-severe PsO group were required to have 1) ≥2 claims for PsO (ICD-9-CM: 696.1) that were ≥30 days apart, and 2) ≥1 PsO claim and ≥1 systemic therapy/phototherapy in the study period. PsA patients were classified into the PsA+minimal skin PsO group if they did not have any PsO claim or phototherapy in the data cut period, or had ≥1 PsO claim but no evidence of systemic therapy or phototherapy in the data cut period. Patient demographics as of the index date, comorbidities, and medication use during the study period were compared between these two groups. Wilcoxon rank sum tests were used to compare continuous variables and Chi-square tests were used to compare binary variables. Bonferroni correction was used to adjust for multiple comparisons.
Results A total of 10,495 patients with PsA+moderate-to-severe PsO and 15,503 patients with PsA+minimal skin PsO were included in this study. Mean age and percent male were comparable (48.46±10.29 vs. 49.92±10.05 years; 48.2% vs. 46.7%). Compared to patients with PsA+minimal skin PsO, those with PsA+moderate-to-severe PsO had slightly higher rates of chronic pulmonary disease (23.6% vs. 21.4%) and liver disease (excluding fatty liver) (15.1% vs. 10.7%), but lower rates of co-prevalent rheumatic disease (5.1% vs. 7.0%) and rheumatoid arthritis (32.2% vs. 35.7%). Patients with PsA+moderate-to-severe PsO also had significant higher rates of several PsA-associated comorbidities, including anxiety (18.8% vs. 15.8%), depression (23.2% vs. 20.1%) and obesity (21.5% vs. 15.9%) (all p<0.0001). Patients with PsA+moderate-to-severe PsO had significantly higher rates of all-cause medication use (99.9% vs. 94.7%) and larger number of unique medications filled (13.38 vs. 11.28) than patients with PsA+minimal skin PsO (both p<0.0001). Significant differences were also observed in the mean number of unique medications filled between these two groups for PsA-related medications (2.78 vs. 2.14), non-PsA-related medications (10.60 vs. 9.14), antidepressants (0.60 vs. 0.55), and antidiabetics (0.30 vs. 0.25) (all p<0.0001).
Conclusions PsA patients with moderate-to-severe PsO had a higher comorbidity burden compared to those with minimal skin PsO, and also incurred significantly more medication use overall and related to PsA and specific comorbid conditions.
Acknowledgement This study is funded by Novartis Pharmaceuticals Corporation.
Disclosure of Interest J. Merola Grant/research support from: Biogen IDEC, AbbVie, Amgen, Pfizer, Consultant for: Biogen IDEC, AbbVie, Eli Lilly, Novartis, Janssen, Momenta, Speakers bureau: AbbVie, V. Herrera Shareholder of: Novartis, Employee of: Novartis, J. Palmer Employee of: Novartis