Inflammatory and lipemic response to red meat intake in women with and without Rheumatoid Arthritis: a single meal study within a randomized controlled trial.

BACKGROUND

The risk of atherosclerotic cardiovascular disease (ASCVD) is increased in Rheumatoid Arthritis (RA). Previous research has suggested that lipid metabolism is altered in RA, but research under postprandial conditions is scarce. The aim of this study was to investigate whether women with RA have a different lipemic and inflammatory response to a mixed meal containing red meat compared to women without RA.

METHODS

Twenty-two women with RA, with modest disease activity, and 22 women without RA matched for age and body mass index (BMI) at the group level consumed a hamburger meal containing ca. 700 kcal (53 E% from fat, 27 E% from carbohydrate). Venous blood was sampled in the fasted state and after 30 min, 1, 2, 3 and 5 h and analysed for lipid species using nuclear magnetic resonance spectroscopy. Postprandial inflammation was measured by interleukin- 6 (IL- 6). The postprandial lipid response was calculated as the incremental area under the curve minimal value, and serial measurements were analysed by repeated measures analysis of variance. Lipid and inflammatory responses were compared by linear regression analysis, adjusted for age, BMI, physical activity, and baseline plasma concentration.

RESULTS

Plasma concentrations of IL- 6, triglycerides (TGs) and very low-density lipoprotein (VLDL) particles increased significantly after the meal compared to baseline within both groups, but no differences were observed between groups. However, the women with RA had a less pronounced response in cholesterol carried in VLDL particles (p = 0.03) and in TGs in the subfraction of VLDL particles with highest density (p = 0.03). No association was found between the response in TGs and IL- 6.

CONCLUSION

This study does not provide compelling evidence for any difference in the lipemic or inflammatory response in women with RA compared with age- and BMI-matched women without RA following ingestion of a mixed, high-fat meal containing red meat. The modest disease activity in women with RA should be considered when interpreting these findings. Subtle group differences found in the lipids carried by VLDL particles warrant further investigation.

TRIAL REGISTRATION

The PIRA (Postprandial Inflammation in Rheumatoid Arthritis) trial was registered 2020-01 - 28 at Clinicaltrials.gov (NCT04247009).