Prospective Analysis of Factors Influencing the Antibody Response to Hepatitis B Vaccine in Hemodialysis Patients

Abstract Background. Patients on maintenance hemodialysis typically show a suboptimal immune response to hepatitis B (HB) virus vaccination compared to the non-uremic population. The aim or our study was the identification of factors implicated in the vaccine response of our hemodialysis patients. Methods. We studied prospectively 63 hemodialysis patients who were seronegative for HB (37 males, 26 females). Their mean age was 62.2±11.28 years (range 35-80) and hemodialysis. Duration 55.96±50.1 months (range 6-225) fourteen of them (22.2%) were diabetics. Our patients followed a four-dose vaccination schedule (0, 1, 2 and 6 months) with 40 μg of a recombinant DNA HB vaccine. The antibody response was determined 1 month after the fourth dose of vaccination by assessing the titre of antiHBs antibodies (ab). Immune response was defined as sufficient when the antiHBs ab level was ≥ 12 mIU/ml. During the 6-month vaccination period we also monitored monthly and time-averaged Kt/V, residual renal function (RRF), BMI, serum creatinine, albumin, transferrin, ferritin, CRP, iPTH and the dose of erythropoietin and Vitamin D that they received. Results. An optimal immune response was achieved in 34 patients (54%, responders) (antiHBs: 295.95±341.67 mIU/ml), whereas 29 patients (46%, non-responders) showed a suboptimal response (antiHBs: 1.98±2.92 mIU/ml) (p=1.75x10 -5 ). There was a statistically significant negative correlation between the antiHBs ab titre and BMI (r=-0.28, p=0.024). A significant difference was also found between the BMI of responders and non-responders as groups (24.8±5.5 vs. 27.2±4.5, p=0.02). Grouping our patients according to the existence of diabetes, age (cut off 60 years), and hemodialysis efficiency (Kt/V≥1.2) we found a statistically significant difference in the antiHBs ab titre between diabetics and non-diabetics (8.43±12.3 vs. 200.2±317.7 mIU/ml, p=0.03), younger and older patients (262±365.09 vs. 84.36±189.1 mIU/ml, p=0.0145) and patients with efficient and inefficient hemodialysis (234.71±337.1 vs. 79.14±200.99 mIU/ml, p=0.032). Treatment with vitamin D analogues, RRF and hypoalbuminemia were not found to be implicated in the immune response of our patients