Tea consumption and risk of bladder cancer in the Bladder Cancer Epidemiology and Nutritional Determinants (BLEND) Study: Pooled analysis of 12 international cohort studies

Journal Article · Tue Mar 29 00:00:00 EDT 2022 · Clinical Nutrition

DOI:https://doi.org/10.1016/j.clnu.2022.03.020· OSTI ID:1976964

Al-Zalabani, Abdulmohsen H. ^[1]; Wesselius, Anke ^[2]; Yi-Wen Yu, Evan ^[3]; van den Brandt, Piet ^[4]; Grant, Eric J. ^[5]; White, Emily ^[6]; Skeie, Guri ^[7]; Liedberg, Fredrik ^[8]; Weiderpass, Elisabete ^[9]; Zeegers, Maurice P. ^[2]

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1. Taibah University, Madinah (Saudi Arabia); OSTI
2. Maastricht University (Netherlands)
3. Southeast University, Nanjing (China); Maastricht University (Netherlands)
4. Maastricht University Medical Centre (Netherlands)
5. Radiation Effects Research Foundation, Hiroshima (Japan)
6. Fred Hutchinson Cancer Research Center, Seattle, WA (United States)
7. UiT the Arctic University of Norway, Tromsø (Norway)
8. Lund University (Sweden)
9. World Health Organization, Lyon (France)

Tea has been shown to be associated with reduced risk of several diseases including cardiovascular diseases, stroke, metabolic syndrome, and obesity. However, the results on the relationship between tea consumption and bladder cancer are conflicting. This research aimed to assess the association between tea consumption and risk of bladder cancer using a pooled analysis of prospective cohort data. Individual data from 532,949 participants in 12 cohort studies, were pooled for analyses. Cox regression models stratified by study centre was used to estimate hazard ratios (HR) and corresponding 95% CIs. Fractional polynomial regression models were used to examine the dose–response relationship. A higher level of tea consumption was associated with lower risk of bladder cancer incidence (compared with no tea consumption: HR = 0.87, 95% C.I. = 0.77–0.98 for low consumption; HR = 0.86, 95% C.I. = 0.77–0.96 for moderate consumption; HR = 0.84, 95% C.I. = 0.75–0.95 for high consumption). When stratified by sex and smoking status, this reduced risk was statistically significant among men and current and former smokers. In addition, dose–response analyses showed a lower bladder cancer risk with increment of 100 ml of tea consumption per day (HR-increment = 0.97; 95% CI = 0.96–0.98). A similar inverse association was found among males, current and former smokers while never smokers and females showed non-significant results, suggesting potential sex-dependent effect. Higher consumption of tea is associated with reduced risk of bladder cancer with potential interaction with sex and smoking status. Further studies are needed to clarify the mechanisms for a protective effect of tea (e.g. inhibition of the survival and proliferation of cancer cells and anti-inflammatory mechanisms) and its interaction with smoking and sex.

• Research Organization: National Academy of Sciences, Washington, DC (United States)
• Sponsoring Organization: European Commission; National Academy of Sciences; USDOE Office of Environment, Health, Safety and Security (AU); World Cancer Research Fund International
• Grant/Contract Number: HS0000031
• OSTI ID: 1976964
• Journal Information: Clinical Nutrition, Journal Name: Clinical Nutrition Journal Issue: 5 Vol. 41; ISSN 0261-5614
• Publisher: Elsevier - European Society for Clinical Nutrition and Metabolism
• Country of Publication: United States
• Language: English

Related Subjects

60 APPLIED LIFE SCIENCES
cohort studies
dose–response analysis
epidemiology
smoking
tea
urinary bladder cancer