Genome-wide enrichment analysis between endometriosis and obesity-related traits reveals novel susceptibility loci

Endometriosis is a chronic inflammatory condition in women that results in pelvic pain and subfertility, and has been associated with decreased body mass index (BMI). Genetic variants contributing to the heritable component have started to emerge from genome-wide association studies (GWAS), although the majority remain unknown. Unexpectedly, we observed an intergenic locus on 7p15.2 that was genome-wide significantly associated with both endometriosis and fat distribution (waist-to-hip ratio adjusted for BMI; WHRadjBMI) in an independent meta-GWAS of European ancestry individuals. This led us to investigate the potential overlap in genetic variants underlying the aetiology of endometriosis, WHRadjBMI and BMI using GWAS data. Our analyses demonstrated significant enrichment of common variants between fat distribution and endometriosis (P = 3.7 × 10(-3)), which was stronger when we restricted the investigation to more severe (Stage B) cases (P = 4.5 × 10(-4)). However, no genetic enrichment was observed between endometriosis and BMI (P = 0.79). In addition to 7p15.2, we identify four more variants with statistically significant evidence of involvement in both endometriosis and WHRadjBMI (in/near KIFAP3, CAB39L, WNT4, GRB14); two of these, KIFAP3 and CAB39L, are novel associations for both traits. KIFAP3, WNT4 and 7p15.2 are associated with the WNT signalling pathway; formal pathway analysis confirmed a statistically significant (P = 6.41 × 10(-4)) overrepresentation of shared associations in developmental processes/WNT signalling between the two traits. Our results demonstrate an example of potential biological pleiotropy that was hitherto unknown, and represent an opportunity for functional follow-up of loci and further cross-phenotype comparisons to assess how fat distribution and endometriosis pathogenesis research fields can inform each other

Association between Laparoscopically Confirmed Endometriosis and Risk of Early Natural Menopause

Importance: Early natural menopause (ENM) has been associated with reduced reproductive span, cardiovascular disease risk, and early mortality. The potential adverse implications of endometrioma surgery for ovarian reserve are known, yet the association of endometriosis with menopausal timing remains understudied. Objective: To investigate the association between endometriosis and risk for ENM. Design, Setting, and Participants: This large, population-based cohort study analyzed data from the Nurses' Health Study II cohort questionnaires from the 1989 to 2015 questionnaire cycles. The sample included premenopausal women aged 25 to 42 years at baseline or enrollment in 1989. Cumulative follow-up rate was greater than 90%, and participants continued follow-up until the onset of ENM, age 45 years, hysterectomy, oophorectomy, cancer diagnosis, death, loss to follow-up, or end of follow-up in May 2017, whichever occurred first. Data analyses were conducted from October 26, 2020, to April 27, 2021. Exposures: Endometriosis diagnosis status was queried in the biennial questionnaires, with participants reporting physician diagnosis and whether the diagnosis was laparoscopically confirmed. Main Outcomes and Measures: Natural menopause before age 45 years. Menopause status was assessed every 2 years. Results: The study included 106633 premenopausal women with a mean (SD) age of 34.8 (4.3) years at baseline, of whom 3921 reported a laparoscopically confirmed endometriosis diagnosis. During 1 508 462 person-years of follow-up, 6640 participants reported being diagnosed with endometriosis, 99993 never reported endometriosis, and 2542 reported experiencing ENM. In the age- and calendar time-adjusted model, laparoscopically confirmed endometriosis was associated with a 50% greater risk for ENM (hazard ratio [HR], 1.51; 95% CI, 1.30-1.74). A similar risk was observed after adjusting for race and ethnicity and time-varying anthropometric and behavioral factors (HR, 1.46; 95% CI, 1.26-1.69). With additional adjustment for reproductive factors, the HR of ENM was attenuated but significant (HR, 1.28; 95% CI, 1.10-1.48). A greater risk of ENM was observed among women who were nulliparous after stratifying by parity (nulliparous vs parous: HR, 1.46 [95% CI, 1.15-1.86] vs 1.14 [95% CI, 0.94-1.39]; P for heterogeneity =.05) or who never used oral contraceptives when stratifying by oral contraceptive use (never vs ever: HR, 2.03 [95% CI, 1.34-3.06] vs 1.20 [95% CI, 1.02-1.42]; P for heterogeneity =.02). No significant differences were observed in the association between endometriosis and ENM when stratifying by body mass index (calculated as weight in kilograms divided by height in meters squared; <25 vs ≥25: HR, 1.20 [95% CI, 0.99-1.45] vs 1.43 [95% CI, 1.11-1.83; P for heterogeneity =.34), cigarette smoking status (never vs ever: HR, 1.36 [95% CI, 1.13-1.65] vs 1.11 [95% CI, 0.87-1.42]; P for heterogeneity =.57), or history of infertility attributed to ovulatory disorder (no vs yes: HR, 1.28 [95% CI, 1.08-1.51] vs 1.28 [95% CI, 0.90-1.82]; P for heterogeneity =.86). Conclusions and Relevance: This cohort study found a risk for ENM in women with laparoscopically confirmed endometriosis. These women compared with those without endometriosis may be at a higher risk for shortened reproductive duration, particularly those who were nulliparous or never used oral contraceptives.. © 2022 American Medical Association. All rights reserved.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Menstrual Cycle Regularity and Length Across the Reproductive Lifespan and Risk of Cardiovascular Disease

Importance: Menstrual cycle characteristics may be associated with an increased risk of cardiovascular disease (CVD). However, existing studies are limited, and few have explored the mediating role of established CVD risk factors. Objective: To explore the associations of menstrual cycle characteristics across the reproductive lifespan with the risk of CVD and to what extent these associations were mediated by hypercholesterolemia, chronic hypertension, and type 2 diabetes. Design, Setting, and Participants: This cohort study prospectively followed Nurses' Health Study II participants between 1993 and 2017 who reported menstrual cycle regularity and length for ages 14 to 17 years and 18 to 22 years at enrollment in 1989 and updated current cycle characteristics in 1993 (at ages 29 to 46 years). Data analysis was performed from October 1, 2019, to January 1, 2022. Exposures: Menstrual cycle regularity and length across the reproductive lifespan. Main Outcomes and Measures: Incident CVD events of interest, including fatal and nonfatal coronary heart disease (CHD; myocardial infarction [MI] or coronary revascularization) and stroke. Results: A total of 80 630 Nurses' Health Study II participants were included in the analysis, with a mean (SD) age of 37.7 (4.6) years and body mass index of 25.1 (5.6) at baseline. Over 24 years of prospective follow-up, 1816 women developed their first CVD event. Multivariable Cox proportional hazards models showed that, compared with women reporting very regular cycles at the same ages, women who had irregular cycles or no periods at ages 14 to 17, 18 to 22, or 29 to 46 years had hazard ratios for CVD of 1.15 (95% CI, 0.99-1.34), 1.36 (95% CI, 1.06-1.75), and 1.40 (95% CI, 1.14-1.71), respectively. Similarly, compared with women reporting a cycle length of 26 to 31 days, women reporting a cycle length 40 days or more or a cycle too irregular to estimate from ages 18 to 22 or 29 to 46 years had hazard ratios for CVD of 1.44 (95% CI, 1.13-1.84) and 1.30 (95% CI, 1.09-1.57), respectively. Mediation analyses showed that subsequent development of hypercholesteremia, chronic hypertension, and type 2 diabetes only explained 5.4% to 13.5% of the observed associations. Conclusions and Relevance: In this cohort study, both irregular and long menstrual cycles were associated with increased rates of CVD, which persisted even after accounting for subsequently established CVD risk factors.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Meat and dairy food consumption and breast cancer: A pooled analysis of cohort studies

Background. More than 20 studies have investigated the relation between meat and dairy consumption and breast cancer risk with conflicting results. Our objective was evaluate the risk of breast cancer associated with meat and dairy food consumption and to assess whether non-dietary risk factors modify the relation. Methods. We combined the primary data from eight prospective cohort studies from North America and Western Europe with at least 200 incident breast cancer assessment of usual food and nutrient intakes, and a validation study of dietary assessment instrument. The pooled database included 351 041 women 7379 of whom were diagnosed with invasive breast cancer during to 15 year of follow-up. Results. We found no significant association between intakes of total meat, red me white meat, total dairy fluids, or total dairy solids and breast cancer risk. Categor analyses suggested a J-shaped association for egg consumption where, comp to women who did not eat eggs, breast cancer risk was slightly decreased am women who consumed <2 eggs per week but slightly increased among women who consumed ≥1 egg per day. Conclusions. We found no significant associations between intake of meat or dairy produ and risk of breast cancer. An inconsistent relation between egg consumption risk of breast cancer merits further investigation