Background/Purpose:

Both patients with psoriatic arthritis (PsA) and ankylosing spondylitis (AS) are at increased risk of cardiovascular disease (CVD). This increased risk is in part attributed to traditional cardiovascular risk factors. Patients with PsA have higher body mass index (BMI) compared to patients with AS. Based on this we hypothesized that patients with PsA are at higher risk of CVD compared to patients with AS. The purpose of the study is to compare the risk of CVD in patients with PsA to patients with AS.

Methods:

Explorys is a clinical research informatics tool that uses unified medical language system ontologies to standardize, normalize and aggregate clinical data from multiple electronic heath records. The data are de-identified and presented through a secure web interface usable by researchers. At the time of this study several million patients from multiple distinct healthcare systems from year 1999 to 2012 were present in the Explorys database. Using the SNOMED hierarchy, we searched for all patients with a diagnosis of either PsA or AS using the terms “ankylosing spondylitis” and “psoriasis with arthropathy.”  This was further stratified by adding search term “anti tumor necrosis factor alpha drug”, and only patients using anti TNF therapy were included in the analysis. Using the first Body mass index (BMI) recorded; we categorized patients into one of three categories: < 25 kg/m2 (normal weight); 25 kg/m2 to < 30 kg/m2 (overweight); and ≥ 30 kg/m2 (obese). Presence of CVD was defined by the occurrence of myocardial infarction (MI), cerebrovascular disease or peripheral vascular disease (PVD). The occurrence of CV events was searched in a temporal sequence. The comparison between the 2 cohorts was made using Fishers exact test.

Results:

We identified 2360 cases of PsA and 1020 cases of AS from the database. Demographics are shown in the table 1. 52.5% patients with PsA had a BMI of more than 30 as compared to 37.8% patients with AS (p=0.0001). A total cholesterol > 200 was found in 41.9% patients with PsA compared to 36.6% with AS (p=0.11). HDL < 40 was found in 34.2% patients with PsA compared to 31% patients with AS (p=0.34).There was no significant difference between the PsA and AS cohorts in terms of prevalence of MI 2.1% vs 1.9% (p= 0.79), cerebrovascular disease 4.2% vs 2.9% (p-value 0.79) and PVD 5.9% vs 5.8% (p=0.93) respectively as shown in table 2.

Conclusion:

Despite higher BMI in patients with PsA, the prevalence of acute MI, cerebrovascular disease and PVD was similar to patients with AS. The results did not support our hypothesis that increased BMI in PsA increases the risk of CVD. Hence, other risk factors need to be further investigated.   

Table 1

Table 2

ACR Meeting Abstracts - https://acrabstracts.org/abstract/risk-of-cardiovascular-disease-among-patients-with-psoriatic-arthritis-compared-to-ankylosing-spondylitis-retrospective-cohort-study/