Dietary components can produce a variety of bioactive substances that maintain a low inflammatory state in the body and participate in the formation of the tumor microenvironment. The dietary inflammatory index (DII) is a new indicator to quantify the inflammatory potential of diet. High DII score is closely associated with the risk of colorectal cancer, but its relationship with upper gastrointestinal cancer (UGIC) is unclear.

This study was conducted to assess the relationship between DII and the risk of UGIC, providing a scientific basis for dietary guidance.

We did a systematic search of PubMed, Web of Science, Embase and the Cochrane Library for studies on the association of DII score and UGIC published in English, and Wanfang Data, CNKI and VIP for those published in Chinese, from inception to October 10, 2022. Two researchers performed literature screening, data extraction, and quality evaluation separately. RevMan 5.4.1 was used for meta-analysis and subgroup analysis.

A total of 11 case-control studies including 9 051 participants were included in this study. Meta-analysis showed that high DII score were associated with an increase in the risk of UGIC〔OR=1.81, 95%CI (1.65, 1.97), P<0.05〕. High DII score also significantly increased the risk of esophageal and gastric cancers〔OR=2.20, 95%CI (1.69, 2.86) ; OR=1.79, 95%CI (1.44, 2.24), P<0.05〕. Subgroup analysis showed that high DII score increased the risk of UGIC by 131% in the European population〔OR=2.31, 95%CI (1.78, 3.00), P<0.05〕, and 98% in the Asian population〔OR=1.98, 95%CI (1.55, 2.53), P<0.05〕. High DII score increased the risk of UGIC by 161% in women〔OR=2.61, 95%CI (1.79, 3.79), P<0.05〕. Moreover, high DII score increased the risk of UGIC by 47% in H. pylori-negative populations〔OR=1.47, 95%CI (1.08, 1.99), P<0.05〕, and 90% in H. pylori-positive populations〔OR=1.90, 95%CI (1.33, 2.71), P<0.05〕. High DII score was associated with a 195% increased risk of UGIC in the population with interviewer-administered Food Frequency Questionnaire (FFQ) 〔OR=2.95, 95%CI (1.96, 4.43), P<0.05〕, and a 68% increased risk of UGIC in the population with self-administered FFQ〔OR=1.68, 95%CI (1.53, 1.85), P<0.05〕. High DII score was associated with a 101% increased risk of UGIC in the population with a higher number of DII components (>30) 〔OR=2.01, 95%CI (1.57, 2.57), P<0.05〕, and a 125% increased risk of UGIC in the population with a lower number of DII components (<30) 〔OR=2.25, 95%CI (1.58, 3.22), P<0.05〕. In addition, high DII score increased the risk of UGIC by 123% in the population with energy-adjusted diet〔OR=2.23, 95%CI (1.85, 2.68), P<0.05〕, and 70% in the population without energy-adjusted diet〔OR=1.70, 95%CI (1.53, 1.88), P<0.05〕. The funnel plot of the literature was asymmetric, showing that there was a certain publication bias.

A pro-inflammatory diet with higher DII score may exacerbate the risk of UGIC, especially in esophageal cancer patients and in the female population.

食物成分可产生多种生物活性物质，维持人体内低度炎症状态，并参与肿瘤微环境形成。膳食炎症指数（DII）是量化膳食炎症潜力的新指标，高水平DII与结直肠癌发生密切相关，但与上消化道肿瘤（UGIC）的关系尚不明确。

评估DII与UGIC发生风险的关系，为膳食指导提供科学依据。

系统检索英文数据库PubMed、Web of Science、Embase、Cochrane Library和中文数据库万方数据知识服务平台、中国知网、维普网，检索日期为建库至2022-10-10。由2位研究者分别独立提取文献数据，并进行文献质量评价。采用RevMan 5.4.1软件进行Meta分析，并进行亚组分析。

本研究共纳入11篇病例对照研究，包括9 051名研究对象。Meta分析结果显示，高水平DII增加UGIC发生风险〔OR=1.81，95%CI（1.65，1.97），P<0.05〕。高水平DII增加食管癌、胃癌发生风险〔OR=2.20，95%CI（1.69，2.86）；OR=1.79，95%CI（1.44，2.24），P<0.05〕。亚组分析结果显示，欧洲人群高水平DII增加131% UGIC发生风险〔OR=2.31，95%CI（1.78，3.00），P<0.05〕，亚洲人群高水平DII增加98% UGIC发生风险〔OR=1.98，95%CI（1.55，2.53），P<0.05〕；女性高水平DII增加161% UGIC发生风险〔OR=2.61，95%CI（1.79，3.79），P<0.05〕；幽门螺杆菌（Hp）阴性人群高水平DII增加47% UGIC发生风险〔OR=1.47，95%CI（1.08，1.99），P<0.05〕，Hp阳性人群高水平DII增加90% UGIC发生风险〔OR=1.90，95%CI（1.33，2.71），P<0.05〕；采用面试官管理的人群高水平DII增加195% UGIC发生风险〔OR=2.95，95%CI（1.96，4.43），P<0.05〕，采用自我管理食物频率问卷（FFQ）的人群高水平DII增加68% UGIC发生风险〔OR=1.68，95%CI（1.53，1.85），P<0.05〕；DII成分数量>30个人群高水平DII增加101% UGIC发生风险〔OR=2.01，95%CI（1.57，2.57），P<0.05〕；DII成分数量<30个人群高水平DII增加125% UGIC发生风险〔OR=2.25，95%CI（1.58，3.22），P<0.05〕；总能量摄入调整的人群高水平DII增加123% UGIC发生风险〔OR=2.23，95%CI（1.85，2.68），P<0.05〕，未进行总能量摄入调整人群高水平DII增加70% UGIC发生风险〔OR=1.70，95%CI（1.53，1.88），P<0.05〕。纳入文献漏斗图不对称，存在发表偏倚。

高水平DII代表的促炎饮食可能会增加UGIC的患病风险，尤其在食管癌及女性群体中更明显。