Dietary inflammatory potential, oxidative balance score, and risk of breast cancer: findings from the Sister Study
Menée aux Etats-Unis à partir de données portant sur 43 563 participantes, cette étude de cohorte analyse l'association entre le potentiel inflammatoire de l'alimentation, un indicateur caractérisant l'équilibre oxydant-antioxydant lié à l'alimentation et le risque de cancer du sein (durée moyenne de suivi : 8,4 ans ; 2 619 cas)
Diet, inflammation, and oxidative stress may be important in breast carcinogenesis, but evidence on the role of the inflammatory and pro‐oxidative potential of dietary patterns is limited. Energy adjusted‐Dietary Inflammatory Index (E‐DII TM) and dietary oxidative balance score (D‐OBS) were calculated for 43,563 Sister Study cohort participants who completed a Block 1998 food frequency questionnaire at enrollment in 2003‐2009 and satisfied eligibility criteria. D‐OBS was validated using measured F2‐isoprostanes and metabolites. High E‐DII score and low D‐OBS represent a more pro‐inflammatory and pro‐oxidant diet, respectively, and associations of quartiles of each index with breast cancer (BC) risk were estimated using multivariable Cox proportional hazards regression. There were 2,619 BCs diagnosed at least 1 year after enrollment (mean follow‐up 8.4 years). There was no overall association between E‐DII and BC risk, whereas there was a suggestive inverse association for the highest versus lowest quartile of D‐OBS (HR 0.92 [95% CI, 0.81‐1.03]). The highest quartile of E‐DII was associated with risk of triple‐negative BC (HR 1.53 [95% CI, 0.99‐2.35]). When the two indices were combined, a pro‐inflammatory/pro‐oxidant diet (highest tertile of E‐DII and lowest tertile of D‐OBS) was associated with increased risk for all BC (HR 1.13 [95% CI, 1.00‐1.27]) and for triple‐negative BC (1.72 [95% CI, 1.10‐2.70]), compared with an anti‐inflammatory/anti‐oxidant diet (lowest tertile of E‐DII and highest tertile of D‐OBS). Diets with increased inflammatory potential and reduced oxidative balance were positively associated with overall and triple‐negative BC.