Title:
Meta-analysis: the impact of nutritional status on the immune response to hepatitis B virus vaccine in chronic kidney disease.

Abstract:
Patients with chronic kidney disease (CKD) typically show a diminished immune response to hepatitis B virus (HBV) vaccine compared with individuals with intact kidney function. A number of inherited or acquired factors have been implicated in this suboptimal response. Patients with chronic kidney disease frequently have a compromised nutritional status; however, the impact of malnutrition on the immune response to hepatitis B virus vaccine in chronic kidney disease patients remains unclear.
To evaluate the influence of nutrition status on the immune response to HBV vaccine in CKD population by performing a systematic review of the literature with a meta-analysis of clinical studies.
Study-specific relative risks were weighted by the inverse of their variance to obtain fixed- and random-effects pooled estimates of impaired vaccine response across the published studies. The risk of poor serological response to HBV vaccine in chronic kidney disease population according to nutritional parameters was regarded as the most reliable outcome end-point. Only studies performing multivariate analysis in order to make adjustments for potential confounders were included.
We identified seven studies (15,172 unique patients with CKD). The serum protection rate after a full course of recombinant or plasma-derived vaccine towards HBV ranged between 40 and 86%. Aggregation of study results showed an independent and adverse effect of poor nutrition status, as mostly detected by serum albumin levels, on the protection rate after HBV vaccine course; the summary estimate for adjusted RR was 1.50 with a 95% confidence interval (CI) of 1.02, 2.21; R(                               i                            ) = 0.01 (random-effects model). The P value for study heterogeneity was significant (Q = 0.0001). In the subgroup of patients who received HBV recombinant vaccine, the relative risk of impaired serological response after HBV vaccination was 1.63 (95% CI, 1.08, 2.45), R(                               i                            ) = 0.90, Q = 0.00001, with poor nutritional parameters at baseline.
An increased risk exists of impaired serologic response to HBV vaccine response among chronic kidney disease patients having poor nutrition status. Additional studies are needed to understand better the mechanisms underlying the relationship between nutritional status and serological response to HBV vaccine among patients with CKD.