Lynn Rosenberg

Regular Physical Inactivity and Ovarian Cancer Risk in the Ovarian Cancer in Women of African Ancestry Consortium

Abstract Background: Regular physical inactivity may increase ovarian cancer risk, but few studies have investigated whether this association is similar among Black and White women. Methods: In a pooled nested case–control study within the Ovarian Cancer in Women of African Ancestry consortium, logistic regression models evaluated regular recreational physical inactivity with risk of epithelial ovarian cancer among Black (223 cases; 1,472 controls) and White women (985 cases; 6,212 controls) enrolled in four cohort studies. Models were further stratified by histologic type. Results: Regular physical inactivity was not associated with the risk of overall ovarian cancer among Black [OR = 1.16; 95% confidence interval (CI), 0.83–1.61] or White women (OR = 1.03; 95% CI, 0.87–1.23). We did not detect associations according to histologic type. Conclusions: Physical inactivity was not associated with ovarian cancer among Black or White women in a consortium of cohort studies. Impact: These results are counter to case–control-based studies and emphasize the complexity of investigating physical activity prospectively.

Racial Differences in Population Attributable Risk for Epithelial Ovarian Cancer in the OCWAA Consortium

Abstract Background The causes of racial disparities in epithelial ovarian cancer (EOC) incidence remain unclear. Differences in the prevalence of ovarian cancer risk factors may explain disparities in EOC incidence among African American (AA) and White women. Methods We used data from 4 case-control studies and 3 case-control studies nested within prospective cohorts in the Ovarian Cancer in Women of African Ancestry Consortium to estimate race-specific associations of 10 known or suspected EOC risk factors using logistic regression. Using the Bruzzi method, race-specific population attributable risks (PAR) were estimated for each risk factor individually and collectively, including groupings of exposures (reproductive factors and modifiable factors). All statistical tests were 2-sided. Results Among 3244 White EOC cases and 9638 controls and 1052 AA EOC cases and 2410 controls, AA women had a statistically significantly higher PAR (false discovery rate [FDR] P < .001) for first-degree family history of breast cancer (PAR = 10.1%, 95% confidence interval [CI] = 6.5% to 13.7%) compared with White women (PAR = 2.6%, 95% CI = 0.8% to 4.4%). After multiple test correction, AA women had a higher PAR than White women when evaluating all risk factors collectively (PAR = 61.6%, 95% CI = 48.6% to 71.3% vs PAR = 43.0%, 95% CI = 32.8% to 51.4%, respectively; FDR P = .06) and for modifiable exposures, including body mass index, oral contraceptives, aspirin, and body powder (PAR = 36.0%, 95% CI = 21.0% to 48.8% vs PAR = 13.8%, 95% CI = 4.5% to 21.8%, respectively; FDR P = .04). Conclusions Collectively, the selected risk factors accounted for slightly more of the risk among AA than White women, and interventions to reduce EOC incidence that are focused on multiple modifiable risk factors may be slightly more beneficial to AA women than White women at risk for EOC.

Race Differences in the Associations between Menstrual Cycle Characteristics and Epithelial Ovarian Cancer

Abstract Background: Menstrual cycle characteristics—including age at menarche and cycle length— have been associated with ovarian cancer risk in White women. However, the associations between menstrual cycle characteristics and ovarian cancer risk among Black women have been sparsely studied. Methods: Using the Ovarian Cancer in Women of African Ancestry (OCWAA) Consortium that includes 1,024 Black and 2,910 White women diagnosed with epithelial ovarian cancer (EOC) and 2,325 Black and 7,549 White matched controls, we investigated associations between menstrual cycle characteristics (age at menarche, age at menstrual regularity, cycle length, and ever missing three periods) and EOC risk by race and menopausal status. Multivariable logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI). Results: Black women were more likely to be <11 years at menarche than White women (controls: 9.9% vs. 6.0%). Compared with ≥15 years at menarche, <11 years was associated with increased EOC risk for White (OR = 1.25; 95% CI, 0.99–1.57) but not Black women (OR = 1.10; 95% CI, 0.80–1.55). Among White women only, the association was greater for premenopausal (OR = 2.20; 95% CI, 1.31–3.68) than postmenopausal women (OR = 1.06; 95% CI, 0.82–1.38). Irregular cycle length was inversely associated with risk for White (OR = 0.78; 95% CI, 0.62–0.99) but not Black women (OR = 1.06; 95% CI, 0.68–1.66). Conclusions: Earlier age at menarche and cycle irregularity are associated with increased EOC risk for White but not Black women. Impact: Associations between menstrual cycle characteristics and EOC risk were not uniform by race.

Racial disparities in epithelial ovarian cancer survival: An examination of contributing factors in the Ovarian Cancer in Women of African Ancestry consortium

AbstractBlack women diagnosed with epithelial ovarian cancer have poorer survival compared to white women. Factors that contribute to this disparity, aside from socioeconomic status and guideline‐adherent treatment, have not yet been clearly identified. We examined data from the Ovarian Cancer in Women of African Ancestry (OCWAA) consortium which harmonized data on 1074 Black women and 3263 white women with ovarian cancer from seven US studies. We selected potential mediators and confounders by examining associations between each variable with race and survival. We then conducted a sequential mediation analysis using an imputation method to estimate total, direct, and indirect effects of race on ovarian cancer survival. Black women had worse survival than white women (HR = 1.30; 95% CI 1.16‐1.47) during study follow‐up; 67.9% of Black women and 69.8% of white women died. In our final model, mediators of this disparity include college education, nulliparity, smoking status, body mass index, diabetes, diabetes/race interaction, postmenopausal hormone (PMH) therapy duration, PMH duration/race interaction, PMH duration/age interaction, histotype, and stage. These mediators explained 48.8% (SE = 12.1%) of the overall disparity; histotype/stage and PMH duration accounted for the largest fraction. In summary, nearly half of the disparity in ovarian cancer survival between Black and white women in the OCWAA consortium is explained by education, lifestyle factors, diabetes, PMH use, and tumor characteristics. Our findings suggest that several potentially modifiable factors play a role. Further research to uncover additional mediators, incorporate data on social determinants of health, and identify potential avenues of intervention to reduce this disparity is urgently needed.

Cohort Profile: The Ovarian Cancer Cohort Consortium (OC3)