Evaluación de la proteína C reactiva, alfa1-antitripsina y lipoproteína(a) como potenciales marcadores biológicos asociados al crecimiento del aneurisma de aorta abdominal

Introduction. Current assessment of asymptomatic infrarenal abdominal aortic aneurysms (AAA) is done solely with serial image techniques. We try to find a useful serological biomarker of AAA activity with potential prognostic value. Patients and methods. We obtained peripheral blood samples from 35 AAA patients (13 3-3.9 cm AAA; 11 4-4.9 cm AAA; 11 > = 5 cm AAA) and 35 controls. We quantified the serum concentration of C-reactive protein (CRP), alphα1-antitrypsin and lipoprotein(a). We registered: clinical data, aortic diameter (ultrasound/CT) at the time of blood sample harvest, and AAA growth in the previous 12 months. We analysed the correlation between each protein and the aortic diameter and growth, using Mann-Whitney, Kruskal-Wallis and Spearman's tests and linear regression. Results. The AAA patients were mostly male (n = 33; 94.3%) and aged 71 ± 6.8 (54-83) years. The AAA diameter (n = 35) was 45 ± 12 (30-71) mm, with expansion (n = 25) 3,1 ± 3,1 (0-10) mm/previous year. The levels of the three proteins were significantly higher in the AAA patients compared to the controls: CRP 4.1 (1.9-7.3) v. 1.9 (0.5-5) mg/L (p = 0.026); alphα1-antitrypsin 147 (131-168) v. 125.5 (114-135.5) mg/dL (p < 0.0001); lipoprotein(a) 47 (20-117.5) v. 27 (9-47) mg/dL (p = 0.022). We found positive correlations CRP-AAA diameter (r = 0.46; p = 0.007) and alphα1-antitrypsin-AAA growth (r = 0,55; p = 0,004), but no association between lipoprotein(a) and AAA diameter or expansion (p > 0.52). CRP concentrations were influenced by statin intake (p = 0.036). There were no correlations for any of the proteins in the control group (p > 0.22). Conclusions. Alphα1-antitrypsin seems promising as a biomarker of AAA activity. CRP shows correlation with AAA size, but is influenced by statin intake. Lipoprotein(a) has not proved useful. [ANGIOLOGÍA 2009; 61: 119-31]