Associations of Dietary Long-Chain ω-3 Polyunsaturated Fatty Acids and Fish Consumption With Endometrial Cancer Risk in the Black Women's Health Study

Abstract

Dietary long-chain (LC) ω-3 polyunsaturated fatty acids (PUFAs), which derive primarily from intakes of fatty fish, are thought to inhibit inflammation and de novo estrogen synthesis. This study prospectively examined the associations of dietary LC ω-3 PUFAs and fish with endometrial cancer risk in 47,602 African-American women living in the United States, aged 21-69 years at baseline in 1995, and followed them until 2013 (n = 282 cases). Multivariable-adjusted Cox regression models estimated hazard ratios and 95% confidence intervals for associations of LC ω-3 PUFA (quintiled) and fish (quartiled) intake with endometrial cancer risk, overall and by body mass index (BMI; weight (kg)/height (m) 2 ). The hazard ratio for quintile 5 of total dietary LC ω-3 PUFAs versus quintile 1 was 0.79 (95% confidence interval (CI): 0.51, 1.24); there was no linear trend. Hazard ratios for the association were smaller among normal-weight women (BMI <25: hazard ratio (HR) = 0.53, 95% CI: 0.18, 1.58) than among overweight/ obese women (BMI ≥25: HR = 0.88, 95% CI: 0.54, 1.43), but these differences were not statistically significant. Fish intake was also not associated with risk (quartile 4 vs. quartile 1: HR = 0.86, 95% CI: 0.56, 1.31). Again hazard ratios were smaller among normal-weight women (HR = 0.65) than among overweight/obese women (HR = 0.94). While compatible with no association, the hazard ratios observed among leaner African-American women are similar to those from recent prospective studies conducted in predominantly white populations.African-American women; docosahexaenoic acid; eicosapentaenoic acid; endometrial cancer; fish; uterine cancer; women's reproductive health Abbreviations: BMI, body mass index; BWHS, Black Women's Health Study; CI, confidence interval; DHA, docosahexaenoic acid; DPA, docosapentaenoic acid; EPA, eicosapentaenoic acid; FFQ, food frequency questionnaire; HR, hazard ratio; LC, long-chain; PUFA, polyunsaturated fatty acid; VITAL, Vitamins and Lifestyle; WHI, Women's Health Initiative.Endometrial cancer is the fourth most common cancer and the leading gynecological malignancy diagnosed in US women (1). Incidence rates are about 9% lower for African-American women relative to white women (2), but a recent study of Surveillance, Epidemiology, and End Results data that corrected for hysterectomy prevalence indicated a higher incidence in black women (3).

Dietary n-3 polyunsaturated fatty acids, fish consumption, and endometrial cancer risk: a meta-analysis of epidemiological studies

“…Fernandez et al reported a dose-response relationship between fish consumption and decreased endometrial cancer risk [ 13 ]. However, such a significant association was not detected in other studies [ 16 , 18 – 23 ]. In two other studies conducted in Asia, high fish consumption was detected to confer an increased risk of developing endometrial cancer [ 24 , 25 ].…”

“…Twelve studies reported the association of fish consumption with endometrial cancer risk comparing the highest category with the lowest category [ 14 – 16 , 18 – 22 , 24 , 25 , 28 , 31 ]. After pooling the results of these studies, we did not detect a significant association between the highest vs .…”

“…Data from eight studies were used to evaluate a non-linear dose-response relationship between fish intake and risk of endometrial cancer risk [ 13 , 15 , 16 , 18 , 22 , 25 , 28 , 31 ]. Assuming a non-linear relationship, the dose-response analysis suggested a non-significant relationship ( p : 0.81).…”

“…In this study, however, authors did not synthesize evidence for the associations of n-3 PUFA including EPA and DHA. Besides, since the conduction of this meta-analysis, multiple additional studies evaluating association of fish consumption have been published [ 14 , 16 , 18 – 20 , 24 , 27 , 28 ]. To better characterize the relationship between intakes of fish/n-3 PUFA and endometrial cancer risk, we thus conducted a systematic review and meta-analysis of all available epidemiological studies up to March 2017.…”

The Potential for Plant-Based Diets to Promote Health Among Blacks Living in the United States

“…Further, European and Asian cohorts have recorded possible risk reduction of colorectal and breast cancers with omega-3 fish consumption [48,49], but more research is needed in Blacks. Brasky et al found no significant association between omega-3 and fish consumption and endometrial cancer risk in 47,602 African American women, although non-significant hazard ratios were more favorable among normal weight women (HR = 0.53; 95% CI = 0.18, 1.58) than in overweight women (HR = 0.88; 95% CI = 0.56, 1.31) [50].…”