Coffee and Tea May Help Reduce Liver Inflammation in People with Hepatitis C

Chronic hepatitis C patients who drink caffeinated filtered coffee on a daily basis were more likely to have lower alanine aminotransferase (ALT) levels, indicating less liver inflammation, according to a study published in the December 11, 2013, edition of PLoS ONE. Black or oolong tea also appeared to have a beneficial effect.

Studies looking at the link between coffee, tea, or other caffeine-containing products and liver health have produced mixed results, but several have shown that coffee consumption is associated with reduced liver inflammation or lessened fibrosis. It is not clear whether the association is related to caffeine, plant phytochemicals, or other factors.

Yachiyo Sasaki and colleagues from Osaka City University in Japan looked at the effect of coffee and tea consumption on serum ALT levels over 12 months among individuals with chronic hepatitis C.

The analysis included 376 patients with detectable HCV RNA in a hospital-based cohort study recruited between August 2005 and July 2006. The majority (about 60%) were women and the mean age was approximately 65 years. People who started interferon-based therapy were excluded. About 60% had normal ALT (<45 IU/L) at baseline while the rest had elevated ALT. Extent of liver fibrosis or cirrhosis was not reported. About half never drank caffeinated filtered coffee and the remainder were roughly evenly divided between those who drank <1 cup per day and those who drank 1 cup or more daily.

Results

• Among 229 participants with normal ALT at baseline, 81% still had normal ALT levels 12 months after recruitment.
• People who drank filtered caffeinated coffee daily were 3 times more likely to maintain normal ALT than those who did not drink filtered coffee (odds ratio [OR] 2.74; p=0.037).
• People who drank decaffeinated coffee, however, had a lower likelihood of maintaining normal ALT, though this fell short of statistical significance (OR 0.26; p=0.076).
• Among 147 patients with higher ALT levels at baseline, 27% experienced ALT reductions of at least 20 IU/L by 12 months after recruitment.
• People who drank filtered coffee had a significantly increased likelihood of ALT reduction (OR 3.79; p=0.034).
• No participants who drank decaffeinated experienced ALT reduction.
• People who drank 4 or more cups of black or oolong tea had a greater likelihood of having normal ALT than those who drank less.
• No significant associations were observed between consumption of unfiltered caffeinated coffee or green tea and ALT changes.

Based on these findings, the study authors concluded, "Among patients with chronic HCV infection, daily consumption of filtered coffee may have a beneficial effect on the stabilization of ALT levels."

"[F]iltered coffee consumption exerted a consistently beneficial effect during 12 months of follow-up, not only for sustained normal ALT levels among patients with normal baseline ALT levels, but also for ALT reduction among patients with higher baseline ALT levels," they elaborated in their discussion. "The key substances seemed to be included in filtered coffee," rather than unfiltered caffeinated coffee, they added.

"The results of the present study suggest that consumption of black tea/oolong tea has a beneficial effect on serum ALT level after 12 months, both among patients with normal baseline ALT levels and among those with higher ALT levels," they continued. "To the best of our knowledge, this is the first study to report a favorable association between consumption of black tea/oolong tea and serum ALT level." 

12/23/13

Reference

Y Sasaki, S Ohfuji, W Fukushima, et al. Effect of Caffeine-Containing Beverage Consumption on Serum Alanine Aminotransferase Levels in Patients with Chronic Hepatitis C Virus Infection: A Hospital-Based Cohort Study. PLoS ONE 8(12):e83382. December 11, 2013.