according to findings from a retrospective study.
When added to the Framingham risk score, the measurement significantly improved its predictive ability, Curtis Sobchak, MD, and colleagues wrote in.
The findings indicate that carotid ultrasound could be a useful addition to cardiovascular risk stratification among these patients.
“Traditional algorithms do not consider other factors that may contribute to increased cardiovascular risk in rheumatic disease patients and tend to underestimate cardiovascular risk,” wrote Dr. Sobchak of the University of Toronto and coauthors.
“The advantage of ultrasound over other modalities for vascular imaging includes lack of radiation, low cost of the examination, and its widespread use in rheumatology for joint evaluation. Thus, this assessment could potentially be performed ‘at the bedside’ during consultation to provide immediate valuable information to complement clinical data from history, physical examination, and laboratory data,” they added.
The study retrospectively examined a prospective, observational cohort of 559 patients with psoriasis alone or psoriasis and psoriatic arthritis enrolled in the University of Toronto Psoriatic Disease Program. The investigators evaluated five ultrasound measures of atherosclerosis, including total plaque area (TPA), mean carotid intima-media thickness (cIMT), maximal cIMT, plaque category, and TPA category. Then they analyzed the risk relationship with major cardiovascular events (CVEs) classified as myocardial infarction, unstable angina, ischemic stroke, revascularization procedures, or cardiovascular-related death. Minor CVEs included stable angina, exacerbation of congestive heart failure, and transient ischemic attack over a mean follow-up close to 4 years.
The mean baseline TPA was 0.18 cm2 and mean cIMT was 639 mcm. Most patients had plaques, including 27.0% with unilateral and 31.5% with bilateral plaques.
The rate of a first CVE during the study period was 1.11 per 100 patient-years, and the rate of a first major CVE was 0.91 per 100 patient-years. The risk of each was significantly related to a higher baseline burden of atherosclerosis.
A multivariate analysis determined that increased TPA at baseline increased the risk of an event by nearly 200% (hazard ratio, 2.85). Mean cIMT was not an independent predictor in the final analysis, “suggesting that TPA is a stronger predictor for CVE than cIMT,” the authors wrote.
Finally, they examined the predictive value of atherosclerosis alone, as well as combined with the Framingham risk score. The 5-year model indicated that the bivariate model was slightly more accurate than the Framingham score alone (area under the curve, 0.84 vs. 0.81), although this was not a significant difference. The predictive value of the Framingham risk score plus maximal cIMT, mean cIMT, or TPA all significantly improved when they were calculated using only high-risk patients (those above the treatment threshold for dyslipidemia).
“To the best of our knowledge this is the first study to assess the utility of various measures of carotid atherosclerosis to predict CVE in patients with psoriasis and PsA [psoriatic arthritis]. ... Combining vascular imaging data with clinical and laboratory measures of traditional cardiovascular risk factors could improve accuracy of cardiovascular risk stratification in patients with psoriatic disease and facilitate earlier initiation of appropriate treatment to reduce CVE in this population,” the investigators wrote.
The study was supported in part by a Young Investigator Operating Grant from the Arthritis Society. Dr. Sobchak had no financial disclosures.
SOURCE: Sobchak C et al. Arthritis Rheumatol. 2019 Jun 5. doi: 10.1002/art.40925.