J Gynecol Oncol.  2019 May;30(3):e23. 10.3802/jgo.2019.30.e23.

Dietary inflammatory index and risk of gynecological cancers: a systematic review and meta-analysis of observational studies

• Liu ZY
• Gao XP
• Zhu S
• Liu YH
• Wang LJ
• Jing CX
• Zeng FF

• KMID: 2440517
• DOI: http://doi.org/10.3802/jgo.2019.30.e23

Abstract

OBJECTIVE
There has been growing body of literatures showing that chronic inflammation might play an important role in cancer development. This meta-analysis aimed to assess the association between the dietary inflammation index (DII) score and gynecological cancers.
METHODS
A systematic search of PubMed, EMBASE and Web of Science up until October 20, 2018 was carried out to retrieve all related cohort and case-control studies. The summary risk assessments were pooled using random-effects models. The dose-response relationship was estimated by linear relationship model.
RESULTS
Twelve case-control studies (10,774 cases/15,958 controls) and six prospective cohort studies (330,363 participants/23,133 incident cases) were included in this meta-analysis. The pooled adjusted relative risk (RR) of gynecological cancers for the highest DII category compared to the lowest category was 1.38, (95% confidence intervals [CIs], 1.21-1.56, p <0.001). A positive dose-response relationship was also noticed. Stratified by study design indicated that, the pooled RRs was significantly higher for case-control studies than cohort studies (p for interaction < 0.001), for studies conducted among participants with body mass index (BMI) ≥25 kg/m² than participants with BMI < 25 kg/m² (p for interaction=0.026), among participants with ovarian cancer and endometrial cancer than participants with breast cancer (p for interaction = 0.038). Meta-regression analysis further confirmed that study design significantly contributed to inter-study heterogeneity (p < 0.001).
CONCLUSION
This meta-analysis suggests that elevated DII is independently associated with a higher risk of gynecological cancers, especially patients with ovarian cancer and endometrial cancer and among obese participants.

Keyword

Gynecologic Neoplasms; Dietary Inflammatory Index; Meta-Analysis; Epidemiologic studies

MeSH Terms

Body Mass Index
Breast Neoplasms
Case-Control Studies
Cohort Studies
Endometrial Neoplasms
Epidemiologic Studies
Female
Genital Neoplasms, Female
Humans
Inflammation
Ovarian Neoplasms
Population Characteristics
Prospective Studies
Risk Assessment