Assessment of the relation between C-reactive protein to albumin ratio and the severity and complexity of peripheral arterial disease

Background: Peripheral arterial disease is associated with increased cardiovascular mortality and morbidity. C-reactive protein and albumin are biomarkers of inflammation and malnutrition that play key roles in the pathophysiological pathways involved in the progression of atherosclerosis and peripheral arterial disease. In this study, we aimed to assess the relationship between C-reactive protein to albumin ratio and the suprapopliteal peripheral arterial disease severity and complexity as assessed by TransAtlantic Inter-Society Consensus-II (TASC-II) classification.

Method: Our study enrolled 224 consecutive patients referred for peripheral angiography with the clinical features of possible peripheral arterial disease at a tertiary care center between January 2016 and September 2019. Level of disease and lesion characteristics were defined with reference to angiographic findings according to the TASC-II classification.

Results: C-reactive protein/albumin ratio levels were significantly higher in TASC-II class C and D than in TASC-II class B patients with a median level of 1.8 to 2.1 vs 1.4, respectively (p = 0.018). In multivariate regression analysis, C-reactive protein to albumin ratio remained an independent predictor of severe peripheral arterial disease. The predictive performance of C-reactive protein to albumin ratio, C-reactive protein, and albumin were compared by Receiver Operating Characteristic curve analysis. C-reactive protein to albumin ratio surpassed C-reactive protein and albumin in predicting peripheral arterial disease severity and complexity. A level of C-reactive protein to albumin ratio > 0.14 predicted a higher grade of suprapopliteal TASC-II class with sensitivity and specificity of 68.2% and 56.0%, respectively.

Conclusion: C-reactive protein to albumin ratio was strongly associated with peripheral arterial disease severity and complexity, as assessed by TASC-II classification. Also, C-reactive protein to albumin ratio was found to be a more accurate marker than C-reactive protein and albumin alone in predicting more severe and complex lesions in patients with peripheral arterial disease.

Keywords: C-reactive protein; C-reactive protein to albumin ratio; Peripheral arterial disease; albumin.