Dietary inflammatory index and ovarian cancer risk in a large Italian case–control study

Abstract

Background While inflammation has been shown to play an important etiologic role in ovarian carcinogenesis, little is known about the association between inflammatory properties of diet and ovarian cancer risk. Methods We explored the association between the dietary inflammatory index (DII) and ovarian cancer risk in a multicentric Italian case-control study conducted between 1992 and 1999. Cases were 1031 women with incident, histologically confirmed ovarian cancer from 4 areas in Italy. Controls were 2,411 women admitted to the same network of hospitals as the cases for acute, non-malignant and non-gynecological conditions, unrelated to hormonal or digestive-tract diseases or committed to long-term modifications of diet. DII scores were computed based on 31 nutrients and food items assessed using a reproducible and validated 78-item food frequency questionnaire. Odds ratios (ORs) were estimated through logistic regression models adjusting for age, total energy intake and other recognised confounding factors. Results Subjects in the highest quartile of DII scores (i.e., with the most pro-inflammatory diets) had a higher risk of ovarian cancer compared to subjects in the lowest quartile (i.e., with an anti-inflammatory diet) (ORQuartile4vs1= 1.47, 95% confidence interval, CI, 1.07, 2.01; p-trend=0.009). When analyses were carried out using continuous DII, a significant positive association with ovarian cancer was observed, the OR for one-unit increment in DII score (corresponding to approximately 8% of its range in the current study, +6.0 to −6.20) was 1.08 (95% CI=1.02, 1.14). Conclusion A pro-inflammatory diet as indicated by higher DII scores is associated with increased ovarian cancer risk.

Dietary inflammatory index and risk of epithelial ovarian cancer in African American women

“…In a population of AA women in the United States, a more pro‐inflammatory diet was positively associated with EOC risk. These findings are consistent with the only other study examining the DII and EOC risk . Although few studies have looked specifically at the inflammatory potential of one's diet in relation to ovarian cancer, individual nutrients and dietary patterns that contribute to inflammation have been assessed previously, yet the results have been fairly inconsistent .…”

“…We observed statistically significant effect modification by both menopausal status and age; among post‐menopausal women and women older than 60 years of age, a more pro‐inflammatory diet was strongly associated with an increased risk of EOC, while no association was seen for pre‐menopausal women and women 60 years of age and younger. Studies in breast, endometrial and ovarian cancer observed similar results, where a positive association between the DII and cancer risk was present only among post‐menopausal women, albeit not statistically significant. In these three studies, age was not assessed as a potential effect modifier.…”

“…These findings are consistent with the only other study examining the DII and EOC risk. 25 Although few studies have looked specifically at the inflammatory potential of one's diet in relation to ovarian cancer, individual nutrients and dietary patterns that contribute to inflammation have been assessed previously, yet the results have been fairly inconsistent. 33 Although fruit and vegetable intake is associated with lower levels of inflammatory biomarkers, 12,34 a protective effect of fruit and vegetable intake on ovarian cancer risk was observed neither in a pooled analysis of 12 cohort studies 35 or in the European Prospective Investigation into Cancer and Nutrition (EPIC) Study.…”

“…[15][16][17][18] Additionally, a more pro-inflammatory diet, as defined by higher DII scores, has been linked to an increased risk of several cancers, including colorectal, 19,20 pancreatic, 21 prostate, 22 breast 23 and endometrial cancer. 24 Specific to ovarian cancer, a recent study 25 observed an increased risk among Italian women who consumed a more proinflammatory diet. However, as that study was conducted among Italian women, the results may not be generalizable to other, non-White populations.…”

Dietary inflammatory index and non-Hodgkin lymphoma risk in an Italian case–control study

“…The DII has been associated with risk of various chronic inflammatory conditions such as colorectal cancer (14–18) and cardiovascular diseases (19, 20). In Italy, the DII has been shown to be associated with various cancers ranging from those of the digestive tract (15, 21, 22) to hormone-sensitive cancers (23–26). …”