Assessment of moderate coffee consumption and risk of epithelial ovarian cancer: a Mendelian randomization study

Research output: Contribution to journalArticle


Background: Coffee consumption has been shown to be associated with various health outcomes in observational studies. However, evidence for its association with epithelial ovarian cancer (EOC) is inconsistent and it is unclear whether these associations are causal.

Methods: We used single nucleotide polymorphisms associated with (i) coffee and (ii) caffeine consumption to perform Mendelian randomization (MR) on EOC risk. We conducted a two-sample MR using genetic data on 44 062 individuals of European ancestry from the Ovarian Cancer Association Consortium (OCAC), and combined instrumental variable estimates using a Wald-type ratio estimator.

Results: For all EOC cases, the causal odds ratio (COR) for genetically predicted consumption of one additional cup of coffee per day was 0.92 [95% confidence interval (CI): 0.79, 1.06]. The COR was 0.90 (95% CI: 0.73, 1.10) for high-grade serous EOC. The COR for genetically predicted consumption of an additional 80 mg caffeine was 1.01 (95% CI: 0.92, 1.11) for all EOC cases and 0.90 (95% CI: 0.73, 1.10) for high-grade serous cases.

Conclusions: We found no evidence indicative of a strong association between EOC risk and genetically predicted coffee or caffeine levels. However, our estimates were not statistically inconsistent with earlier observational studies and we were unable to rule out small protective associations.


  • Jue-Sheng Ong
  • Liang-Dar Hwang
  • Gabriel Cuellar-Partida
  • Nicholas G Martin
  • Georgia Chenevix-Trench
  • Michael C J Quinn
  • Marilyn C Cornelis
  • Puya Gharahkhani
  • Penelope M Webb
  • Stuart MacGregor
  • Håkan Olsson (Contributor)
  • Ovarian Cancer Association Consortium
External organisations
  • QIMR Berghofer Medical Research Institute
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Cancer and Oncology


  • Carcinoma, Ovarian Epithelial/epidemiology, Coffee/adverse effects, Female, Humans, Mendelian Randomization Analysis, Odds Ratio, Ovarian Neoplasms/epidemiology, Polymorphism, Single Nucleotide, Risk Factors
Original languageEnglish
Pages (from-to)450-459
JournalInternational Journal of Epidemiology
Issue number2
Publication statusPublished - 2018 Apr 1
Publication categoryResearch