Higher fibre intake tied with reduced inflammation and CVD risk in older adults: Study

Higher intake of dietary fibre has been associated with lower inflammation, but whether there are differences in this association by a source of dietary fibre (ie, cereal, vegetable, or fruit) has not been studied to date.

A study was conducted to evaluate the associations of total fibre intake and source (ie, cereal, vegetable, and fruit fibre intake) with inflammation and to evaluate whether inflammation mediates the inverse association between dietary fibre intake and cardiovascular disease (CVD).

At the baseline visit (1989-1990) of 4125 adults aged 65 years or older in an ongoing US cohort study, dietary intake was assessed by a food frequency questionnaire among study participants without prevalent CVD (stroke and myocardial infarction) at enrollment. Inflammation was assessed from blood samples collected at baseline with immunoassays for markers of inflammation. Multivariable linear regression models tested the association of dietary fiber intake with inflammation. Also assessed was whether each inflammatory marker and its composite derived from principal component analysis mediated the association of baseline cereal fibre intake with the development of CVD (stroke, myocardial infarction, and atherosclerotic cardiovascular death) through June 2015. Data from June 1, 1989, through June 30, 2015, were analyzed.

Results:

Of 4125 individuals, 0.1% (n = 3) were Asian or Pacific Islander, 4.4% (n = 183) were Black, 0.3% (n = 12) were Native American, 95.0% (n = 3918) were White, and 0.2% (n = 9) were classified as other. Among these 4125 individuals (2473 women [60%]; mean [SD] age, 72.6 [5.5] years; 183 Black individuals [4.4%]; and 3942 individuals of other races and ethnicities [95.6%] [ie, race and ethnicity other than Black, self-classified by participant]), an increase in total fibre intake of 5 g/d was associated with significantly lower concentrations of C-reactive protein (adjusted mean difference, −0.05 SD; 95% CI, −0.08 to −0.01 SD; P = .007) and interleukin 1 receptor antagonist (adjusted mean difference, −0.04 SD; 95% CI, −0.07 to −0.01 SD; P < .02) but with higher concentrations of soluble CD163 (adjusted mean difference, 0.05 SD; 95% CI, 0.02-0.09 SD; P = .005). Among fibre sources, only cereal fibre was consistently associated with lower inflammation. Similarly, cereal fibre intake was associated with lower CVD incidence (adjusted hazard ratio, 0.90; 95% CI, 0.81-1.00; 1941 incident cases). The proportion of the observed association of cereal fibre with CVD mediated by inflammatory markers ranged from 1.5% for interleukin 18 to 14.2% for C-reactive protein, and 16.1% for their primary principal component.

Thus, the results of this study suggest that cereal fibre intake was associated with lower levels of various inflammatory markers and lower risk of CVD and that inflammation-mediated approximately one-sixth of the association between cereal fibre intake and CVD.

Reference

Intake and Sources of Dietary Fiber, Inflammation, and Cardiovascular Disease in Older US Adults by Rupak Shivakoti et al. published in the JAMA Network Open.

https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2790576

Keywords:

Higher fibre intake, reduced inflammation, CVD risk, older adults, JAMA Network Open, Rupak Shivakoti, Mary L. Biggs, Luc Djoussé, Peter Jon Durda, Jorge R. Kizer, Bruce Psaty, Alex P. Reiner, Russell P. Tracy, David Siscovick, Kenneth J. Mukamal,