The relation between hemoglobin variability and carotid intima-media thickness in chronic hemodialysis patients

Hemoglobin variability is a common problem among hemodialysis patients. We have previously demonstrated an association between Hb variability and left ventricular mass index. In this study, we investigated a possible relation between Hb variability and carotid intima-media thickness (CIMT). Twelve-month hemoglobin (Hb) values of 135 patients on maintenance hemodialysis were examined retrospectively. The range of 11-12 gr/dl was accepted as normal according to the KDOQI guidelines. Hemoglobin levels were classified as: Hb < 11 gr/dl:Low, Hb = 11-12 gr/dl:Normal and Hb > 12 gr/dl:High. According to 12-month Hb trajectory, the patients were divided into three groups: low-normal (LN), normal-high (NH) and low-high (LH). The CIMT measurements were taken on common carotid arteries bilaterally, and the average of these measurements were taken. The groups were compared in terms of CIMT measurements, demographic and laboratory features. The LN, NH and LH groups were similar in terms of age, gender, incidence of diabetes mellitus, hypertension and cardiovascular diseases. Duration of hemodialysis, hemodialysis adequacy, serum lipids and CaxP products were also similar among the groups. The mean CIMT value was 0.601 +/- 0.107, 0.744 +/- 0.139 and 0.604 +/- 0.134 mm in the LN, LH and NH groups, respectively (p < 0.001). CIMT was significantly higher in LH than in the other two groups. In our study, when the three groups with similar risk factors for atherosclerosis were examined, we found that the LH group with the highest hemoglobin variability has the highest CIMT. This study is the first study to demonstrate that Hb variability is associated with an increase in CIMT in HD patients.