In patients with seronegative axial or peripheral spondyloarthritis (SpA), red blood cell distribution width (RDW) was associated with cardiovascular disease (CVD) risk factors, represented by the atherosclerotic cardiovascular disease (ASCVD) 10-year risk score, as well as age, race, hemoglobin, albumin, C-reactive protein (CRP), statin use, and HLA-B27 positivity, according to study findings published in the International Journal of Rheumatology. In addition, treatment of SpA did not significantly affect RDW.
A retrospective chart review of US Veterans Affairs patients with SpA was performed to evaluate the relationships between RDW and ASCVD scoring factors (age, lipid profile, and smoking, diabetes, and hypertension status), as well as CRP, hemoglobin, albumin, and absolute lymphocyte count (ALC). Treatment status, race, and HLA-B27 status were all taken into consideration during the evaluation.
A total of 43 patients (median age, 56; 97.7% men) had complete data and were included in the analysis. Of the patients, 32 (74.4%) were positive for HLA-B27 and the median values for ASCVD 10-year risk score, RDW, and CRP were 13.1%, 13.45%, and 8.78 mg/L, respectively.
Positive correlations were found between RDW and 10-year ASCVD score (r =0.42; P =.008) as well as age (r =0.360; P =.016) and there was no significant change in ASCVD score following SpA treatment (P =.31). In addition, RDW was positively correlated with CRP (r =0.57; P <.001), while albumin was negatively correlated with ASCVD score (r=−0.36; P =.03) and CRP (r=−0.39; P =.02). There was no correlation found between ALC and ASCVD score (P =.8), although there was a tendency for ALC to be associated with cardiac conduction abnormalities, CVD, and CVD events. Finally, ASCVD score was positively correlated with age (r =0.88; P <.001) and hypertension therapy (P =.006).
Study strengths included the use of Veteran Affairs medical records and laboratory data that offered a comprehensive clinical picture of the included participants. Study limitations included small sample size, retrospective nature, calculation of ASCVD scores at different times than collection of lipid profiles, demographics that skewed older and male, possible censoring bias effect secondary to imputation to 40 years, and potential selection bias as a result of a high rate of exclusion.
The investigators advised, “In combination with larger nonautoimmune disease cohort data, these findings support further investigation of relationships between RDW, albumin, ALC, ASCVD 10-year risk score, and CVD risk in a larger cohort of spondyloarthritis patients.”
Ahmad H, Khan M, Laugle M, et al. Red cell distribution width is positively correlated with atherosclerotic cardiovascular disease 10-year risk score, age, and CRP in spondyloarthritis with axial or peripheral disease. Int J Rheumatol. 2018;2018:1-8.