The Second Affiliated Hospital, Institute of Urology and Organ Transplantation, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China.
The Second Affiliated Hospital, Trauma Center & Critical Care Medicine, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China.
BMC Med. 2022 Feb 3;20(1):39. doi: 10.1186/s12916-021-02229-5.
Evidence associating diet with the incidence of renal cell carcinoma (RCC) is inconclusive. We aimed to summarize evidence associating dietary factors with RCC incidence and assess the strength and validity of this evidence.
We conducted an umbrella review of systematic reviews or meta-analyses (SRoMAs) that assessed the association between diet and RCC incidence. Through April 2021, PubMed, Web of Science, Embase, The Cochrane Library, Scopus, and WCRF were searched. Two independent reviewers selected studies, extracted data, and appraised the quality of SRoMAs. According to credibility assessment criteria, evidence can be divided into five categories: convincing (class I), highly suggestive (class II), suggestive (class III), weak (class IV), and nonsignificant (class V).
Twenty-nine meta-analyses were obtained after screening. After excluding 7 overlapping meta-analyses, 22 meta-analyses including 502 individual studies and 64 summary hazard ratios for RCC incidence were included: dietary patterns or dietary quality indices (n = 6), foods (n = 13), beverages (n = 4), alcohol (n = 7), macronutrients (n =15), and micronutrients (n =19). No meta-analyses had high methodological quality. Five meta-analyses exhibited small study effects; one meta-analysis showed evidence of excess significance bias. No dietary factors showed convincing or highly suggestive evidence of association with RCC in the overall analysis. Two protective factors had suggestive evidence (vegetables (0.74, 95% confidence interval 0.63 to 0.86) and vitamin C (0.77, 0.66 to 0.90)) in overall analysis. One protective factor had convincing evidence (moderate drinking (0.77, 0.70 to 0.84)) in Europe and North America and one protective factor had highly suggestive evidence (cruciferous vegetables (0.78, 0.70 to 0.86)) in North America.
Although many meta-analyses have assessed associations between dietary factors and RCC, no high-quality evidence exists (classes I and II) in the overall analysis. Increased intake of vegetables and vitamin C is negatively associated with RCC risk. Moderate drinking might be beneficial for Europeans and North Americans, and cruciferous vegetables might be beneficial to North Americans, but the results should be interpreted with caution. More researches are needed in the future.
PROSPERO CRD42021246619.
与肾癌（RCC）发病率相关的饮食证据尚无定论。我们旨在总结与饮食因素与 RCC 发病率相关的证据，并评估该证据的强度和有效性。
我们对评估饮食与 RCC 发病率之间关系的系统评价或荟萃分析（SRoMAs）进行了伞式审查。截至 2021 年 4 月，我们检索了 PubMed、Web of Science、Embase、The Cochrane Library、Scopus 和 WCRF。两名独立的审查员选择研究、提取数据并评估 SRoMAs 的质量。根据可信度评估标准，证据可分为五类：有说服力（I 类）、高度提示（II 类）、提示（III 类）、弱（IV 类）和无意义（V 类）。
筛选后获得 29 项荟萃分析。排除 7 项重叠的荟萃分析后，纳入了 22 项荟萃分析，包括 502 项个体研究和 64 项 RCC 发病率汇总风险比：饮食模式或饮食质量指数（n = 6）、食物（n = 13）、饮料（n = 4）、酒精（n = 7）、宏量营养素（n = 15）和微量营养素（n = 19）。没有荟萃分析具有较高的方法学质量。5 项荟萃分析显示存在小样本效应；1 项荟萃分析显示存在过度显著偏倚的证据。在总体分析中，没有饮食因素与 RCC 具有有说服力或高度提示性的关联证据。两个保护因素具有提示性证据（蔬菜（0.74，95%置信区间 0.63 至 0.86）和维生素 C（0.77，0.66 至 0.90））。在欧洲和北美，一个保护因素具有有说服力的证据（适度饮酒（0.77，0.70 至 0.84）），在北美，一个保护因素具有高度提示性的证据（十字花科蔬菜（0.78，0.70 至 0.86））。
尽管许多荟萃分析评估了饮食因素与 RCC 之间的关联，但在总体分析中没有高质量的证据（I 类和 II 类）。增加蔬菜和维生素 C 的摄入量与 RCC 风险呈负相关。适度饮酒可能对欧洲人和北美人有益，十字花科蔬菜可能对北美人有益，但结果应谨慎解释。未来需要更多的研究。
PROSPERO CRD42021246619。
