OBJECTIVES: Postprandial inflammation post-high-fat meals may be linked to cardiovascular disease (CVD). CVD incidence increases with age
however, whether older adults experience greater postprandial inflammation remains unclear. We examined whether analyzing age categorically versus continuously influenced relationships between age and postprandial inflammatory measures. DESIGN: Cross-sectional. SETTING: Laboratory for Applied Nutrition and Exercise Science at Oklahoma State University (Stillwater, OK, USA). PARTICIPANTS: 56 apparently healthy adults ages 20-69 years. MEASUREMENTS: We measured interleukin (IL)-1β, IL-6, IL-8, IL-10, and tumor necrosis factor (TNF)-α at baseline, 2-, 4-, and 6 -hs post-high-fat meal (9 kcal/kg
70% fat). Data were examined in the full sample with paired t-tests (baseline to peak), by pre-defined age groups (i.e., 18-35, 36-49, 50-59, 60-69) using ANCOVA, and continuously using linear regression. RESULTS: Across the full sample, IL-1β, IL-6, and IL-8 increased after the high-fat meal (p's≤0.018). Cytokine differences post-high-fat meal by age category were generally not observed. However, age was positively associated with IL-6 incremental AUC when examined continuously (b = 0.029
p = 0.010). CONCLUSION: These data suggest increasing age is linked to a greater IL-6 response to a high-fat meal. Further, examining age continuously may have greater utility when studying aging and postprandial inflammation. REGISTRATION: N/A (secondary analysis).