The epidemiologic factors associated with breast density: A review

In recent years, some studies have evaluated the epidemiologic factors associated with breast density. However, the variant and inconsistent results exist. In addition, breast density has been proved to be a significant risk factor associated with breast cancer. Our review summarized the published studies and emphasized the crucial factors including epidemiological factors associated with breast density. In addition, we also discussed the potential reasons for the discrepant results with risk factors. To decrease the incidence and mortality rates for breast cancer, in clinical practice, breast density should be included for clinical risk models in addition to epidemiological factors, and physicians should get more concentrate on those women with risk factors and provide risk-based breast cancer screening regimens.

Influential factors and prediction model of mammographic density among Chinese women

To evaluate the characteristics and influential factors of breast density and establish a new model for predicting breast density in Chinese women, so as to provide a basis for breast cancer screening techniques and duration.A total of 9412 women who were selected from screening and intervention techniques for Breast and Cervical Cancer Project between April 2018 and June 2019 were enrolled in this study. Selected women were randomly assigned to training and validation sets in a ratio of 1:1. Univariable and multivariable analyzes were performed by Logistic regression model. Nomogram was generated according to the results of multivariate analysis. Calibration, area under curve (AUC) and akaike information criterion (AIC) were used for measuring accuracy of prediction model.There were 377 (4.0%) women in breast imaging reporting and data system (BI-RADS) A category, 2164 (23.0%) in B category, 5749 (61.1%) in C category and 1122 (11.9%) in D category. Age duration, educational attainment, history of benign diseases, breastfeeding history, menopausal status, and body mass index (BMI) were imputed as independent influential factors for breast density in multivariable analysis. The AUC and AIC of training and validation set were 0.7158, 0.7139, and 4915.378, 4998.665, respectively.This study indicated that age, educational attainment, history of benign breast disease, breastfeeding history, menopausal status and BMI were independent influential factors of breast density. Nomogram generated on the basis of these factors could relatively predict breast density, which in turn could be used for recommendations of breast cancer screening techniques.

Association Between Parity and the Age at Menopause and Menopausal Syndrome in Northwest China

This study evaluated the relationships between parity and the age at menopause and menopausal syndrome among Chinese women in Gansu. A total of 7236 women aged 40 to 55 years met study eligibility criteria. The modified Kupperman Menopausal Index scale was used to assess the severity of menopausal syndrome. Cox regression was applied to estimate hazard ratio and 95% confidence interval, and logistic regression was performed to calculate odds ratio and confidence interval. The mean age at menopause was 47.91 ± 3.31 years. There is no relationship between parity and age at menopause. Women with nulliparity or multiparity seemed to have higher risks of moderate and severe menopausal syndrome. The potential beneficial effects of one or two births on menopausal syndrome were also observed by applying the multivariable logistic regression analysis, particularly in urogenital symptoms. Women with nulliparity and multiparity appeared to be at the higher risks of menopause syndrome.

Immigration history, lifestyle characteristics, and breast density in the Vietnamese American Women's Health Study: a cross-sectional analysis

PURPOSE

Breast density is an important risk factor for breast cancer and varies substantially across racial-ethnic groups. However, determinants of breast density in Vietnamese immigrants in the United States (US) have not been studied. We investigated whether reproductive factors, immigration history, and other demographic and lifestyle factors were associated with breast density in Vietnamese Americans.

METHODS

We collected information on demographics, immigration history, and other lifestyle factors and mammogram reports from a convenience sample of 380 Vietnamese American women in California aged 40 to 70 years. Breast Imaging Reporting and Data System (BI-RADS) breast density was abstracted from mammogram reports. Multivariable logistic regression was used to investigate the association between lifestyle factors and having dense breasts (BI-RADS 3 or 4).

RESULTS

All participants were born in Viet Nam and 82% had lived in the US for 10 years or longer. Younger age, lower body mass index, nulliparity/lower number of deliveries, and longer US residence (or younger age at migration) were associated with having dense breasts. Compared to women who migrated at age 40 or later, the odds ratios and 95% confidence intervals for having dense breasts among women who migrated between the ages of 30 and 39 and before age 30 were 1.72 (0.96-3.07) and 2.48 (1.43-4.32), respectively.

CONCLUSIONS

Longer US residence and younger age at migration were associated with greater breast density in Vietnamese American women. Identifying modifiable mediating factors to reduce lifestyle changes that adversely impact breast density in this traditionally low-risk population for breast cancer is warranted.

Preliminary investigation of mammographic density among women in Riyadh: association with breast cancer risk factors and implications for screening practices

PURPOSE

Improved mammographic sensitivity is associated with reduced mammographic density. This study aims to: provide a preliminary report on mammographic density among women in Riyadh; identify risk factors associated with mammographic density; and consider the potential implications for screening practices.

METHODS

Based on a cross-sectional design, we examined a total of 792 women using an area-based mammographic density method (LIBRA). Spearman's correlation, Mann-Whitney U, Kruskal-Wallis and binary logistic regression were used for analyses.

RESULTS

The study population had a mean age of 49.6 years and a high proportion of participants were overweight or obese (90%). A large number of women had low mammographic density, with a mean dense breast area of 19.1 cm² and percent density of 10.3 cm². Slightly more than half of the variations in the dense breast area and percent density models were explained by BMI. In the adjusted analyses, BMI, menopausal status, age at menarche and number of children remained statistically significant predictors.

CONCLUSION

Given the high proportion of women with low mammographic density, our findings suggest that women living in Riyadh may not require additional imaging strategies beyond mammography to detect breast cancers. The high proportion of obese women reported here and across Saudi Arabia suggests that mammographic density is less likely to have an adverse impact on mammographic sensitivity. Thus and to improve clinical outcomes among Saudi women, annual mammography and commencing screening at a younger age are suggested. Additional studies are required to shed further light on our findings.