Association between breast cancer and reproductive health noted

Association between breast cancer and reproductive health noted | Image Credit: © Aliaksandr Marko - © Aliaksandr Marko - stock.adobe.com.

The age at menarche, number of pregnancies, and number of full-term pregnancies (FTPs) are reduced among women in the Caribbean with breast cancer (BC), according to a recent study published in JAMA Network Open.¹

BC is the fourth leading cause of cancer mortality worldwide, with an increased mortality rate of 17% in low- to middle-income countries. One of the highest BC rates has been observed in the Caribbean.² In this region, women are often diagnosed at a younger age, indicating an increased prevalence among premenopausal women.¹

The cultural and ethnic diversity of the Caribbean population, as well as high rates of BC, allow for a multifaceted lens to evaluate health outcomes. These include reproductive health outcomes, which lean toward modern lifestyle norms in this region.

To evaluate reproductive patterns among BC patients in the Caribbean region, investigators conducted a cross-sectional study. Patients with invasive BC or ovarian cancer between June 1, 2010, and June 30, 2018, born in the Caribbean were included in the analysis. These participants self-identified as female and received an invasive BC diagnosis at any age.

Birth cohorts included before 1950, 1950 to 1959, 1960 to 1969, and 1970 onward. A survey was distributed to obtain data about participants’ family history of BC and ovarian cancer, age at first pregnancy, number of pregnancies, number of FTPs, number of biologic siblings, age at menarche, menopausal status, and age at menopause.

Race and ethnicity data was also obtained. Categories of race and ethnicity included Asian, Black, East Indian, White, and 2 or more races. Medical records were assessed for body mass index (BMI), age at BC diagnosis, and total abdominal hysterectomy with salpingo-oophorectomy (TAH-BSO) status.

Categories for age at menarche included 12 years or less, 13 years, 14 years, and 15 years or older. Number of pregnancies included 0, 1, 2, and 3 or more. The same categories were used for number of FTPs as number of pregnancies.

Age at pregnancy was reported as under 20 years, 20 to 24 years, 25 to 29 years, and 30 years or older. BMI categories included 25, 25 to 29.9, and 30 or higher. Finally, age at natural menopause categories included 45 years or younger, 46 to 50 years, and over 50 years.

There were 995 women with a primary BC diagnosis included in the analysis, aged a mean 46.6 years at BC diagnosis. Of women, 0.4% were Asian, 81.8% were Black, 13.2% were East Indian, 3% were White, and 1.2% were 2 or more races. Premenopausal status was reported in 57.5%.

Rates of BMI at 30 or higher, menarche before age 12 years, 3 or more FTPs, and pregnancy when aged 20 to 24 years were 41.5%, 46.7%, 41.1%, and 35.1%, respectively. There were 177 women born before 1950, 254 between 1950 and 1959, 330 between 1960 and 1969, and 234 from 1970 onward. Overweight or obesity were reported in a majority of patients.

Family history of BC or ovarian cancer was not linked to participants’ decade of birth. However, the mean number of biological siblings differed between the birth cohorts, at 6.6 for before 1950, 5.8 for 1950 to 1959, 6.1 for 1960 to 1969, and 4.5 for 1970 onward.

Rates of women experiencing menarche before age 12, no pregnancies, nulliparity, and natural menopause before the age of 45 years increased over time. However, TAH-BSO was less common in the younger birth groups.

An increase in BC associated with positive germline variants increased over time, from 9.6% before 1950 to 17.1% from 1970 onward. A younger age at BC diagnosis was linked to increased risks of younger age at menarche, fewer pregnancies, fewer FTPS, younger age at menopause, and older age at first pregnancy.

The mean age at BC diagnosis was 45 years for those experiencing menarche when aged under 12 years, vs 49.9 years for menarche at age 14 years and 49.1 years for menarche at age 15 years, indicating a significant difference. Additionally, the mean age of BC was lower in women who were never pregnant and in nulliparous women.

These results indicated a link between BC incidence and reproductive health outcomes across 4 generations. Investigators concluded interventions targeting other modifiable BC factors are necessary to compensate for the shift in reproductive patterns.

References

1. Sanchez-Covarrubias AP, Chery MJ, Barreto-Coehlo P, et al. Reproductive Risk Factor Patterns in Caribbean Women With Breast Cancer Across 4 Generations. JAMA Netw Open. 2024;7(10):e2438091. doi:10.1001/jamanetworkopen.2024.38091
2. RazzaghiH, Quesnel-CrooksS, ShermanR,et al. Leading causes of cancer mortality—Caribbean region, 2003-2013.MMWR Morb Mortal Wkly Rep. 2016;65(49):1395-1400. doi:10.15585/mmwr.mm6549a3