Association Between the Dietary Inflammatory Index and Fracture Risk in Older Adults: a Systematic Review and Meta-analysis

Objective: We explored correlations between the Dietary Inflammatory Index (DII) and fracture risk in older adults.

Methods: We systematically searched MEDLINE, PubMed, Science Direct, Scopus, and CNKI for all relevant epidemiological studies published through October 16, 2023. Because observational studies were included in the meta-analysis, we used a random-effects model to pool the study-specific effect sizes and 95% confidence intervals (CIs). We assessed study quality using the Newcastle-Ottawa scale. This meta-analysis was registered in PROSPERO.

Results: Eight studies with 462,986 participants were included, with five cohort studies, two cross-sectional studies, and one case-control study. An analysis of heterogeneity among the eight included studies resulted in I = 87.1%, indicating significant between-study heterogeneity; hence, the random-effects model was adopted to generate the combined effect size. We found that the DII was positively associated with fracture (relative risk: 1.188, 95% CI: 1.043-1.354). This result was further confirmed in leave-one-out sensitivity analysis.

Conclusions: Our study provides evidence suggesting that diets high in pro-inflammatory components might increase the fracture risk among older people. Decreased consumption of pro-inflammatory foods and increased consumption of anti-inflammatory foods are suggested to prevent adverse fracture outcomes. More prospective studies involving both sexes are warranted to verify the results.