Vitamin D and the racial difference in the genotype 1 chronic hepatitis C treatment response

• Published in: The American journal of clinical nutrition Vol. 96; no. 5; pp. 1025 - 1031
• Main Authors: Weintraub, Steven J, Fleckenstein, Jacquelyn F, Marion, Tony N, Madey, Margaret A, Mahmoudi, Tahar M, Schechtman, Kenneth B
• Format: Journal Article
• Language: English
• Published: Bethesda, MD American Society for Clinical Nutrition 01.11.2012; American Society for Nutrition; American Society for Clinical Nutrition, Inc
• Subjects: Adult; African Americans; Aged; Antiviral Agents - therapeutic use; Biological and medical sciences; Black or African American - genetics; blood serum; chronic hepatitis C; clinical nutrition; Cross-Sectional Studies; Feeding. Feeding behavior; Female; Fundamental and applied biological sciences. Psychology; genotype; Genotype & phenotype; Hepacivirus - metabolism; Hepatitis; Hepatitis C; Hepatitis C virus; Hepatitis C, Chronic - drug therapy; Hepatitis C, Chronic - ethnology; Hepatitis C, Chronic - genetics; Hepatitis C, Chronic - metabolism; Humans; immune response; Interferon-alpha - therapeutic use; liver cirrhosis; Liver diseases; Logistic Models; Male; Middle Aged; patients; Physiology; Polyethylene Glycols - therapeutic use; Polymorphism, Single Nucleotide; Racial differences; Recombinant Proteins - therapeutic use; Retrospective Studies; Ribavirin - therapeutic use; RNA, Viral - blood; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Viruses; Vitamin D; Vitamin D - analogs & derivatives; Vitamin D - blood; Vitamin D - metabolism; Whites; Young Adult; Infection; Human; Treatment; Vitamin D; Viral disease; Digestive diseases; Hepatic disease; Genotype; Viral hepatitis C
• ISSN: 0002-9165; 1938-3207
• DOI: 10.3945/ajcn.112.039974

Background: African Americans with genotype 1 chronic hepatitis C attain a sustained virologic response (SVR) at only approximately one-half the rate of whites after peginterferon and ribavirin treatment. The serum concentration of 25-hydroxyvitamin D [25(OH)D] has recently been established as a predictor of treatment response. Therefore, the low serum concentrations of 25(OH)D found among African Americans may contribute to the low response rate; however, to our knowledge, none of the studies of vitamin D in chronic hepatitis C treatment have included a significant number of black patients.Objective: The objective was to compare the relation between the 25(OH)D concentration and genotype 1 chronic hepatitis C treatment response in African Americans with that in whites.Design: This cross-sectional analysis included 106 African American and 65 white patients with genotype 1 chronic hepatitis C.Results: Consistent with previous studies, we found that the SVR rate in the white patients increased significantly with an increasing serum concentration of 25(OH)D [SVR rates were 20%, 46%, and 70% for 25(OH)D serum concentrations <20, 20–35, and >35 ng/mL, respectively; P-trend = 0.008]; however, there was no relation between the SVR rate and 25(OH)D serum concentration in the African American patients [SVR rates were 32%, 28%, and 33% for 25(OH)D serum concentrations <20, 20–35, and >35 ng/mL, respectively; P-trend = 0.832]. We also found an analogous racial difference in the relation between the extent of liver fibrosis and the 25(OH)D concentration.Conclusion: Racial differences in vitamin D physiology or race-specific factors that modify the effects of vitamin D may affect the immune response to genotype 1 hepatitis C virus.