A Study on the Relationship between Serum Beta 2-Microglobulin Levels, Underlying Chronic Kidney Disease, and Peripheral Arterial Disease in High-Vascular-Risk Patients.
BACKGROUND
Serum beta 2-microglobulin (B2M) levels have been found to be increased in patients with peripheral arterial disease (PAD), yet it is still unknown whether B2M correlates with PAD intensity.


OBJECTIVE
We aim to evaluate the correlation between B2M and the ankle-brachial index (ABI) values in high-vascular-risk patients.


METHODS
This is a cross-sectional study of 63 high-vascular-risk patients admitted to the Cardiology Department or evaluated as outpatients in the Internal Medicine Department of our institution. Patients were classified into two groups according to their ABI: patients without PAD (n = 44, ABI values between 0.9 and 1.4) and patients with PAD (n = 19, ABI values lower than 0.9 or higher than 1.4). We performed univariate and multivariate analysis based on a multiple linear regression model.


RESULTS
Serum B2M levels were higher in patients with pathological ABI values than in those without PAD (2.36 ± 1.13 vs. 1.80 ± 0.65 mg/L; P<0.05). We found no correlation between B2M and ABI in our total population (r = -0.12) or in patients with PAD (r = -0.09; NS for both comparisons). Age, gender, arterial hypertension, estimated glomerular filtration rate (eGFR), uric acid, total cholesterol, and LDL-cholesterol correlated with B2M in the univariate analysis. In the final linear regression model, eGFR, uric acid and total cholesterol correlated independently with B2M (P<0.01).


CONCLUSIONS
We found no correlation between B2M levels and ABI values in high-vascular-risk patients that could usefully help in the subsequent diagnosis of PAD. However, we observed a significant correlation between B2M and eGFR, even when renal function was only slightly impaired.
Vascular Risk Unit, Internal Medicine Department, Fundación de Investigación Biomédica, Hospital Universitario La Princesa, Madrid, Spain.
Diego
D
Real de Asúa
Vascular Risk Unit, Internal Medicine Department, Fundación de Investigación Biomédica, Hospital Universitario La Princesa, Madrid, Spain.
Ramón
R
Puchades
Vascular Risk Unit, Internal Medicine Department, Fundación de Investigación Biomédica, Hospital Universitario La Princesa, Madrid, Spain.
Iluminada
I
García-Polo
Vascular Risk Unit, Internal Medicine Department, Fundación de Investigación Biomédica, Hospital Universitario La Princesa, Madrid, Spain.
Carmen
C
Suárez
Ankle-Brachial Index; Beta 2-Microglobulin; Glomerular Filtration Rate; Peripheral Arterial Disease; Renal Insufficiency