Hypovitaminosis D and its relation to demographic and laboratory data among hepatitis C patients.

BACKGROUND: The relationship between 25-hydroxyvitamin D [25(OH)D] serum levels and response to antiviral therapy and laboratory data in HCV infection remains unclear. The aim of this study was to determine pre-treatment 25(OH)D serum level among HCV infected individuals and to evaluate the association between vitamin D status, virological response, and laboratory data. MATERIAL AND METHODS: Baseline serum 25(OH)D levels were measured in 237 chronic HCV infected patients (139 female, age 53.7 ± 11.2 years) using chemiluminescence immunoassay. Correlations between serum 25(OH)D levels, virological and laboratory data regarding HCV infection as well as sustained virological response (SVR) to antiviral therapy were evaluated. RESULTS: Mean serum values of 25(OH)D was 26.2 ± 12 ng/mL and prevalence of vitamin D deficiency (< 30 ng/mL) was 66.2%. Advanced age (> 55 years), high mean values of LDL, total cholesterol, HDL and low mean values of alkaline phosphatase and hemoglobin were statistically associated to vitamin D deficiency. Antiviral treatment was underwent by 133 HCV patients and 44.3% of them achieved SVR. Most of individuals that presented SVR also presented 25(OH)D level higher than 30ng/mL (55.9%). SVR was associated to low mean values of LDL, total cholesterol and platelets; high mean values of ALT, AST and low fibrosis grade. CONCLUSIONS: In conclusion, low vitamin D levels were observed among HCV infected patients and was associated to laboratory findings, however baseline 25(OH)D level is not independently associated with SVR.

Association between vitamin D and hepatitis C virus infection: a meta-analysis.

AIM: To evaluate the association between 25-hydroxyvitamin D [25(OH)D] and sustained virological response (SVR) in hepatitis C virus (HCV) infected individuals. METHODS: Relevant studies were identified by systematically searching MEDLINE databases up to March 2012 and abstracts of the European and American Congress of Hepatology conducted in 2011. Studies must provide information on SVR and the levels of 25(OH)D3 and/or 25(OH)D2 [henceforth referred to as 25(OH)D] in sera samples from HCV infected individuals. The inclusion criteria were: clinical studies that included HCV infected patients aged older than 18 years regardless of HCV genotype or ethnic group; provided information on SVR rates; and were reported in the English language as full papers. Due to the heterogeneity of studies in categorizing serum vitamin D levels, a cut-off value of 30 ng/mL of serum 25(OH)D was used. Heterogeneity was assessed using I² statistics. The summary odds ratios with their corresponding 95%CI were calculated based on a random-effects model. RESULTS: Overall, 11 studies (8 observational and 3 interventional) involving 1575 individuals were included and 1117 HCV infected individuals (71%) showed low vitamin D levels. Most of the studies included mono-infected HCV individuals with the mean age ranging from 38 to 56 years. Four studies were conducted in human immunodeficiency virus/HCV infected individuals. Regarding vitamin D measurement, most of the studies employed radioimmunoassays (n = 5) followed by chemiluminescence (n = 4) and just one study employed high performance/pressure liquid chromatography (HPLC). Basal vitamin D levels varied from 17 to 43 ng/mL in the studies selected, and most of the HCV infected individuals had genotype 1 (1068/1575) with mean viral load varying from log 4.5-5.9 UI/mL. With regard to HCV treatment, most of the studies (n = 8) included HCV individuals without previous treatment, where the pooled SVR rate was 46.4%. High rates of SVR were observed in HCV individuals with vitamin D levels above 30 ng/mL (OR = 1.57; 95%CI: 1.12-2.2) and those supplemented with vitamin D (OR = 4.59; 95%CI: 1.67-12.63) regardless of genotype. CONCLUSION: Our results demonstrated high prevalence of vitamin D deficiency and high SVR in individuals with higher serum vitamin D levels or receiving vitamin D supplementation.