Impact of caffeine in hepatitis C virus infection: a systematic review and meta-analysis.
OBJECTIVE
Hepatitis C virus (HCV) infection is one of the most common causes of cirrhosis. Several studies have linked caffeine consumption to a lower degree of liver fibrosis and inflammation among patients with chronic HCV infection, but the results were inconsistent. This meta-analysis was carried out with the aim of assessing the impact of caffeine consumption among HCV-infected patients.


METHODS
A literature search was performed using MEDLINE and EMBASE from inception to January 2016. Studies that reported relative risks, odd ratios, or hazard ratios comparing the risk of advanced liver fibrosis or the risk of moderate to severe liver inflammation among HCV-infected patients who consumed caffeine on a regular basis versus those who did not were included. Pooled odds ratios (OR) and 95% confidence interval (CI) were calculated using a random-effect, generic inverse-variance method.


RESULTS
Five studies were included in the fibrosis analysis. The pooled OR of advanced liver fibrosis in HCV-infected patients who consumed caffeine on a regular basis versus those who did not was 0.48 (95% CI, 0.30-0.76, I=52%). Three studies were included in the inflammation analysis. The pooled OR of moderate to severe histologic inflammation among HCV-infected patients who consumed caffeine on a regular basis versus those who did not was 0.61 (95% CI, 0.35-1.04, I=43%).


CONCLUSIONS
Our study showed a decreased risk of advanced liver fibrosis and liver inflammation among HCV-infected patients who consumed caffeine on a regular basis. Whether consumption of caffeine plays a role in the management of HCV infection requires further investigations.
aDepartment of Internal Medicine, Bassett Medical Center, Cooperstown, New York bDepartment of Internal Medicine, Division of Rheumatology, Mayo Clinic, Rochester, Minnesota, USA cDepartment of Medicine, Division of Rheumatology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Karn
K
Wijarnpreecha
Charat
C
Thongprayoon
Patompong
P
Ungprasert
D000284:Administration, Oral; D001628:Beverages; D002110:Caffeine / Q000008:administration & dosage*; D000697:Central Nervous System Stimulants / Q000008:administration & dosage*; D016009:Chi-Square Distribution; D018450:Disease Progression; D005260:Female; D006526:Hepatitis C / Q000175:diagnosis / Q000453:epidemiology* / Q000821:virology; D006801:Humans; D008103:Liver Cirrhosis / Q000175:diagnosis / Q000453:epidemiology / Q000517:prevention & control* / Q000821:virology; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011379:Prognosis; D065840:Protective Factors; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index
D000697:Central Nervous System Stimulants; D002110:Caffeine