Dietary fiber intake and mortality among survivors of myocardial infarction: prospective cohort studyBMJ 2014; 348 doi: https://doi.org/10.1136/bmj.g2659 (Published 29 April 2014) Cite this as: BMJ 2014;348:g2659
- Shanshan Li, doctoral candidate1,
- Alan Flint, research scientist2,
- Jennifer K Pai, assistant professor of medicine3,
- John P Forman, assistant professor of medicine4,
- Frank B Hu, professor12,
- Walter C Willett, professor12,
- Kathryn M Rexrode, associate professor of medicine5,
- Kenneth J Mukamal, associate professor of medicine6,
- Eric B Rimm, associate professor12
- 1Department of Epidemiology, Harvard School of Public Health, 655 Huntington Avenue, Boston, MA 02115, USA
- 2Department of Nutrition, Department of Epidemiology, Boston, MA, USA
- 3Channing Division of Network Medicine, Brigham and Women’s Hospital, Boston, MA, USA
- 4Renal Division, Brigham and Women’s Hospital, Boston, MA, USA
- 5Department of Preventive Medicine, Brigham and Women’s Hospital, Boston, MA, USA
- 6General Medicine, Beth Israel Deaconess Medical Center, Brookline, MA, USA
- Correspondence to: S Li
- Accepted 31 March 2014
Objective To evaluate the associations of dietary fiber after myocardial infarction (MI) and changes in dietary fiber intake from before to after MI with all cause and cardiovascular mortality.
Design Prospective cohort study.
Setting Two large prospective cohort studies of US women and men with repeated dietary measurements: the Nurses’ Health Study and the Health Professionals Follow-Up Study.
Participants 2258 women and 1840 men who were free of cardiovascular disease, stroke, or cancer at enrollment, survived a first MI during follow-up, were free of stroke at the time of initial onset of MI, and provided food frequency questionnaires pre-MI and at least one post-MI.
Main outcome measures Associations of dietary fiber post-MI and changes from before to after MI with all cause and cardiovascular mortality using Cox proportional hazards models, adjusting for drug use, medical history, and lifestyle factors.
Results Higher post-MI fiber intake was significantly associated with lower all cause mortality (comparing extreme fifths, pooled hazard ratio 0.75, 95% confidence interval 0.58 to 0.97). Greater intake of cereal fiber was more strongly associated with all cause mortality (pooled hazard ratio 0.73, 0.58 to 0.91) than were other sources of dietary fiber. Increased fiber intake from before to after MI was significantly associated with lower all cause mortality (pooled hazard ratio 0.69, 0.55 to 0.87).
Conclusions In this prospective study of patients who survived MI, a greater intake of dietary fiber after MI, especially cereal fiber, was inversely associated with all cause mortality. In addition, increasing consumption of fiber from before to after MI was significantly associated with lower all cause and cardiovascular mortality.
We thank Lydia Liu, Donna Spiegelman, and Ellen Hertzmark for their help with programming; the staff and participants in the Nurses’ Health Study and the Health Professionals Follow-up Study, Channing Division of Network Medicine, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School.
Contributors: SL had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. EBR and KJM conceived and designed the study and analysed and interpreted the data. EBR, WCW, FBH, and KJM acquired the data. SL and EBR drafted the manuscript. SL, EBR, WCW, FBH, KJM, AF, MJKP, and JPF critically revised the manuscript for important intellectual content. SL carried out the statistical analysis. EBR and WCW obtained funding. EBR, WCW, FBH, and KJM, and AF were responsible for administrative, technical, or material support and study supervision. EBR is guarantor.
Funding: This study was supported by National Institute of Health grants AA11181, HL35464, HL34594, HL60712, CA55075, CA87969, and CA055075. The funders play no role in the study design, data collection, analysis and interpretation, the writing of the manuscript, and the decision to submit the article for publication.
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; AF receives research funding for a separate unrelated project from the General Mills Bell Institute of Nutrition; no financial relationships with any organisation that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work.
Ethical approval: This study was approved by institutional review board at Harvard School of Public Health (ID of the approval: 2008P000327). Study participants gave informed consent before taking part.
Data sharing: No additional data available.
Transparency: The lead author (the manuscript’s guarantor) affirms that the manuscript is an honest, accurate, and transparent account of the study being reported; that no important aspects of the study have been omitted; and that any discrepancies from the study as planned (and, if relevant, registered) have been explained.
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