The Inflammatory Potential of Diet and Pain Incidence: A Cohort Study in Older Adults.

BACKGROUND

Despite its importance, evidence regarding pain prevention is inadequate. Leveraging the growing knowledge on how diet regulates inflammation, we examined the association of 3-year changes in the inflammatory potential of diet with pain incidence over the subsequent 3 years.

METHODS

We used data from 819 individuals aged ≥60 years and free of pain in 2012, drawn from the Spanish Seniors-ENRICA-1 cohort. The inflammatory potential of diet was estimated via a validated diet history and 2 indices: the dietary inflammatory index (DII) and the empirical dietary inflammatory index (EDII). The frequency, severity, and number of locations of incident pain were combined into a scale that classified participants as suffering from no pain, intermediate pain, or highest pain.

RESULTS

Shifting the diet toward a higher inflammatory potential was associated with subsequent increased risk of highest pain (fully-adjusted relative risk ratio [95% confidence interval] per 1-standard deviation increment in the DII and the EDII = 1.45 [1.16,1.80] and 1.21 [0.98,1.49], respectively) and intermediate pain (0.99 [0.75,1.31] and 1.37 [1.05,1.79]). The 3 components of the pain scale followed similar trends, the most consistent one being pain severity (moderate-to-severe pain: DII = 1.39 [1.11,1.74]; EDII = 1.35 [1.08,1.70]). The association of increasing DII with highest incident pain was only apparent among the less physically active participants (2.08 [1.53,2.83] vs 1.02 [0.76,1.37]; p-interaction = .002).

CONCLUSION

An increase in the inflammatory potential of diet was associated with higher pain incidence over the following years, especially among the less physically active participants. Future studies in older adults should assess the efficacy of pain prevention interventions targeting the inflammatory potential of diet.