Tea consumption and cerebral hemorrhage risk: a meta-analysis

Abstract

Background: Tea contains many polyphenols with biological properties such as antithrombosis and antioxidation. Recent observational studies on tea consumption concerning cerebral hemorrhage risk have reported inconsistent results. This meta-analysis aimed to summarize the accumulated evidence on the association between tea consumption and cerebral hemorrhage risk.

Methods: Web of Science, PubMed, Embase, and Scopus databases were searched to identify relevant studies through December 2021. Relative risks (RRs) or odds ratios (ORs) from observational studies were synthesized.

Results: Ten studies involving over 721,827 participants were included. Higher tea consumption was correlated with a 23% (RR = 0.77; 95% CI 0.66-0.89) lower risk of cerebral hemorrhage. Subgroup meta-analyses indicated higher tea consumption was beneficial in preventing cerebral hemorrhage risk for green tea, alcohol-adjusted, fruit/vegetables-adjusted, and physical activity-adjusted subgroups, respectively (P < 0.01). Dose-response analysis indicated each one-cup (120 ml/cup) increment in tea or green tea intake/day was correlated with an average of 2% (RR = 0.98, 95% CI 0.976-0.990), or 6% (RR = 0.94; 95% CI 0.92-0.97) lower cerebral hemorrhage risk.

Conclusions: This study suggests that daily tea consumption is related to a lower risk of cerebral hemorrhage among adults. Green tea consumption appears to be more beneficial in preventing cerebral hemorrhage. Physical activity, fruit/vegetables, and alcohol may affect the relationship between tea consumption and hemorrhagic stroke. Future studies should investigate the interplay of tea with these factors.

Keywords: Antiendothelial dysfunction; Antioxidation; Antithrombosis; Polyphenols; Prevention.