Distribution Pattern of Atherosclerosis in the Abdomen and Lower Extremities and Its Association with Clinical and Hematological Factors

Lupus Anticoagulant and Anticardiolipin Antibody IgG are Associated with Increased Atherosclerosis at the Suprainguinal Elastic and Infrainguinal Muscular Arteries in the Abdomen and Lower Extremities

Purpose

Whether antiphospholipid antibodies (aPLs) cause atherosclerosis in certain arteries with specific compositions and locations remains unknown. We investigated the relationship between aPLs and their association with locations of atherosclerosis in the arteries of the abdomen and lower extremities.

Methods

Of 2273 patients, 697 who underwent computed tomography angiography of the abdomen and lower extremities and aPL evaluation were included. Atherosclerosis distribution score (ADS) was employed to quantify atherosclerosis severity. Multiple linear regression analysis was performed using the ADS of the suprainguinal elastic and infrainguinal muscular arteries as dependent variables and all aPLs, conventional risk factors of atherosclerosis, and coagulation-related factors as independent variables.

Results

In the suprainguinal elastic and infrainguinal muscular arteries, common risk factors for higher ADS were age, smoking, hypertension, higher glycated hemoglobin, male sex, decreased protein S, and increased homocysteine. Lupus anticoagulant (LA) and increased triglyceride level in the suprainguinal elastic arteries and anticardiolipin antibody (aCL) immunoglobulin (Ig)G, longer alcohol consumption duration, and increased fibrinogen level in the infrainguinal muscular arteries were also risk factors for higher ADS.

Conclusion

LA and aCL IgG were associated with atherosclerosis in the suprainguinal elastic and infrainguinal muscular arteries, respectively. aPLs could predict the location of atherosclerosis.

Earlier onset of peripheral arterial thrombosis in homozygous MTHFR C677T carriers than in other MTHFR genotypes: a cohort study

To investigate whether age at first presentation of pure peripheral arterial thrombosis (PAT) in lower and upper limbs and in the splanchnic circulation occurs earlier in carriers of the methylenetetrahydrofolate reductase (MTHFR) T677T genotype compared to the heterozygous and wild type and to identify predictors of a possible earlier onset. Retrospective cohort study on 27 MTHFR TT, 29 MTHFR TC and 29 MTHFR CC participants; data regarding age, sex, age at PAT, clinical history (dyslipidaemia, hypertension, smoking, obesity) and homocysteine (HC) measured by immunoassay were collected. Age at PAT was lower in MTHFR TT than MTHFR TC and CC (43 ± 9 vs 47 ± 9 vs 51 ± 4 years, respectively, p = 0.02); plasma HC was higher in MTHFR TT than in the other groups (25 ± 19 vs 12.7 ± 6.7 vs 11.3 ± 3.3 μmol/l, respectively, p < 0.001) while the activated partial thromboplastin ratio (aPTTr) was lower in MTHFR TT than in other genotypes (0.90 ± 0.10 vs 0.97 ± 0.12 vs 0.97 ± 0.08 μmol/L p < 0.001). Among categorical variables, MTHFR TT and dyslipidaemia independently predicted age at AT (p = 0.01 & p = 0.03, respectively) whereas among the continuous variables HC independently predicted age at PAT (p = 0.02) as well as the aPTTr (p = 0.001); smoking predicted lower limb PAT (p = 0.005). MTHFR TT carriers develop their first PAT an average of 4 and 8 years earlier than MTHF CT and CC genotypes; MTHFR TT, dyslipidaemia and plasma HC contribute to the prematurity of the PAT while the interplay between elevated HC and smoking may affect type of arterial district occlusion.