Diet and risk of diverticular disease in Oxford cohort of European Prospective Investigation into Cancer and Nutrition (EPIC): prospective study of British vegetarians and non-vegetariansBMJ 2011; 343 doi: https://doi.org/10.1136/bmj.d4131 (Published 19 July 2011) Cite this as: BMJ 2011;343:d4131
- Francesca L Crowe, nutritional epidemiologist,
- Paul N Appleby, senior statistician,
- Naomi E Allen, epidemiologist,
- Timothy J Key, professor of epidemiology
- 1Cancer Epidemiology Unit, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7LF, UK
- Correspondence to: F L Crowe
- Accepted 22 May 2011
Objective To examine the associations of a vegetarian diet and dietary fibre intake with risk of diverticular disease.
Design Prospective cohort study.
Setting The EPIC-Oxford study, a cohort of mainly health conscious participants recruited from around the United Kingdom.
Participants 47 033 men and women living in England or Scotland of whom 15 459 (33%) reported consuming a vegetarian diet.
Main outcome measures Diet group was assessed at baseline; intake of dietary fibre was estimated from a 130 item validated food frequency questionnaire. Cases of diverticular disease were identified through linkage with hospital records and death certificates. Hazard ratios and 95% confidence intervals for the risk of diverticular disease by diet group and fifths of intake of dietary fibre were estimated with multivariate Cox proportional hazards regression models.
Results After a mean follow-up time of 11.6 years, there were 812 cases of diverticular disease (806 admissions to hospital and six deaths). After adjustment for confounding variables, vegetarians had a 31% lower risk (relative risk 0.69, 95% confidence interval 0.55 to 0.86) of diverticular disease compared with meat eaters. The cumulative probability of admission to hospital or death from diverticular disease between the ages of 50 and 70 for meat eaters was 4.4% compared with 3.0% for vegetarians. There was also an inverse association with dietary fibre intake; participants in the highest fifth (≥25.5 g/day for women and ≥26.1 g/day for men) had a 41% lower risk (0.59, 0.46 to 0.78; P<0.001 trend) compared with those in the lowest fifth (<14 g/day for both women and men). After mutual adjustment, both a vegetarian diet and a higher intake of fibre were significantly associated with a lower risk of diverticular disease.
Conclusions Consuming a vegetarian diet and a high intake of dietary fibre were both associated with a lower risk of admission to hospital or death from diverticular disease.
We thank all the participants in the EPIC-Oxford cohort for their invaluable contribution to the study, Anna Zawadzka for her help with obtaining permission to access data from hospital records in England and Scotland, and Neeraj Bhala for his valuable advice on this manuscript.
Contributors: FLC specified the analyses and wrote the manuscript. PNA performed the analyses and edited drafts of the manuscript. NEA specified analyses and edited drafts of the manuscript. TJK conceived the study, specified analyses, and edited drafts of the manuscript. All authors had full access to all of the data (including statistical reports and tables) in the study and can take responsibility for the integrity of the data and the accuracy of the data analysis. FLC and TJK are guarantors.
Funding: The EPIC-Oxford study was funded by Cancer Research UK (grant number: C570/A11691). The funders played no role in designing or conducting the study or in the collection, management, analysis, and interpretation of the data, nor did they have any input into the preparation, review, or approval of this manuscript.
Competing interests: All authors have completed the ICMJE uniform disclosure form at www.icmje.org/coi_disclosure.pdf (available on request from the corresponding author) and declare: no support from any organisation for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; TJK is a member of the Vegan Society, UK.
Ethical approval: The EPIC-Oxford Study has been approved by the multicentre research ethics committee (MREC/02/0/90), and all study participants gave written informed consent to be included. The Information Centre for Health and Social Care in England and the Information and Statistics Division in Scotland gave approval for access and linkage to hospital records.
Data sharing: No additional data available.
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