Association of physical activity, body mass index and reproductive history with breast cancer by menopausal status in Iranian women

Systematic Review and Meta-Analysis of Lifestyle and Reproductive Factors Associated with Risk of Breast Cancer in Asian Women

BACKGROUND

Assessing breast cancer risks from lifestyle and reproductive factors is critical for developing population-specific risk prediction tools. However, limited studies have evaluated these risks in recent Asian birth cohorts.

METHODS

We systematically reviewed articles published from January 2010 to December 2023, examining breast cancer risk factors in Asian women. Data were described narratively, estimates pooled, and prevalence and attributable proportions compared across Asian populations.

RESULTS

Of the 128 studies reviewed, 103 reported adjusted effect sizes for meta-analysis. Lifestyle and reproductive factors were predictive of breast cancer risk in Asian women, with varying impacts on premenopausal and postmenopausal women. Relative risks were similar within Asian populations and in comparison to European populations, except for menarche, menopause, and hormone receptor therapy. However, risk factor distributions differed across populations. While alcohol intake (21%) and oral contraceptive use (20%) emerged as the most attributable modifiable risk factors in Europeans, passive smoking (24%) and higher BMI (17%, ≥24 kg/m2 among postmenopausal women) were predominant in Asians.

CONCLUSIONS

Our study shows that while the effects of lifestyle and reproductive breast cancer risk factors are largely similar across different populations, their distributions vary.

IMPACT

Our analysis underscores the importance of considering population-specific risk factor distributions when developing risk prediction tools for Asian populations.

Breast cancer risk factors in Iranian women: a systematic review and meta-analysis of matched case-control studies

BACKGROUND

Identifying breast cancer risk factors is a critical component of preventative strategies for this disease. This study aims to identify modifiable and non-modifiable risk factors of breast cancer in Iranian women.

METHODS

We used international databases (PubMed/Medline, Scopus, Web of Knowledge, and Embase) and national databases (SID, Magiran, and ISC) to retrieve relevant studies until November 13, 2022. The odds ratio (OR) with a 95% confidence interval using the random-effect model was used to estimate the pooled effect. The publication bias was assessed by the Egger and Begg test. A sensitivity analysis was conducted to evaluate the effect of each included study on the final measurement.

RESULTS

Of the 30,351 retrieved articles, 24 matched case-control records were included with 12,460 participants (5675 newly diagnosed cases of breast cancer and 6785 control). This meta-analysis showed that of the known modifiable risk factors for breast cancer, obesity (vs normal weight) had the highest risk (OR = 2.17, 95% CI 1.47 to 3.21; I² = 85.7) followed by age at marriage (25-29 vs < 18 years old) (OR = 2.00, 95% CI 1.53 to 2.61; I² = 0), second-hand smoking (OR = 1.86, 95% CI 1.58 to 2.19; I² = 0), smoking (OR = 1.83, 95% CI 1.41 to 2.38; I² = 18.9), abortion history (OR = 1.44, 95% CI 1.02 to 2.05; I² = 66.3), oral contraceptive use (OR = 1.35, 95% CI 1.11 to 1.63; I² = 74.1), age at marriage (18-24 vs < 18 years old) (OR: 1.22, 95% CI 1.02 to 1.47; I² = 0). Of non-modifiable risk factors, history of radiation exposure (OR = 3.48, 95% CI 2.17 to 5.59; I² = 0), family history of breast cancer (OR = 2.47, 95% CI 1.83 to 3.33; I² = 73), and age at menarche (12-13 vs ≥ 14 years old) (OR = 1.67, 95% CI 1.31-2.13; I² = 25.4) significantly increased the risk of breast cancer.

CONCLUSIONS

Since most risk factors related to breast cancer incidence are modifiable, promoting healthy lifestyles can play an influential role in preventing breast cancer. In women with younger menarche age, a family history of breast cancer, or a history of radiation exposure, screening at short intervals is recommended.

Effectiveness of a self-management mobile app on the quality of life of women with breast cancer: a study in a developing country

BACKGROUND

Self-management involves taking responsibility for personal health and taking the initiative to do so. This can be accomplished by learning information and skills that will help consider the difficulties may encounter during and after cancer treatment. With this perspective, we have aimed to develop a self-management mobile app for women with breast cancer in Iran and evaluate its impact on the quality of life of patients.

METHOD

This study is a methodological study in 2021. We developed the app during three phases. The first phase aimed at identifying educational content and designing user experience, the second phase aimed at developing and implementing the app, and the third phase aimed at evaluating pre-and post-implementation.

RESULT

In this study, an Android app for self-management women with breast cancer was developed. According to the results of the pre-and post-implementations among the most significant changes were in the quality of life level, highest respectively: social avoidance (Pre: 6.41-Post: 3.56), negative feelings (Pre: 5.93 - Post: 3.40), sexual function (Pre: 6.80 - Post: 5.04), sexual interest (Pre: 6.41 - Post: 4.75) and pain (Pre: 6.37 - Post: 4.97). And least the changes respectively: distress-family (Pre: 7 - Post: 7), distress-recurrence (Pre: 4.49 - Post: 4.38), benefits (Pre: 2.47 - Post: 3.12), appearance (Pre: 4.10 - Post: 3.32). Also, we calculated the usability evaluation of this app with the system usability scale (SUS); the overall rating score was 83/100, an excellent level (> 80.3), and a grade A.

CONCLUSION

The study shows that a breast cancer self-management app can support and improve the quality of life of women with breast cancer. We conducted this study to show that by developing a self-management app, women with breast cancer can improve their quality of life, - by increasing their self-management skills.

Understanding breast cancer risk factors: is there any mismatch between laywomen perceptions and expert opinions

Background

Women’s perception and knowledge of breast cancer signs, symptoms, and risk factors could be conducive to breast cancer risk management and interventions. The present study aimed to explore Iranian laywomen perceptions and expert opinions regarding breast cancer risk factors.

Methods

This qualitative study was conducted from March to November 2019 in Mashhad, northeast of Iran. Through purposive sampling, 24 laywomen (women with and without BC) and 10 experts of different fields including oncology, surgery, gynecology and reproductive health were selected. Data collection was carried out using semi-structured interviews, which was mainly focused on the participants’ understanding and perception of BC risk factors. The data was analyzed utilizing conventional content analysis developed by Graneheim & Lundman. Components of trustworthiness, including credibility, dependability, confirmability, and transferability were considered.

Results

The main category of risk factors, which emerged from the lay participants’ data analysis, were “unhealthy lifestyle and habits” , “hormonal influences”, “environmental exposures”, “Individual susceptibility “and “belief in supernatural powers”. The experts had similar perspectives for certain risk factors, yet not for all. The category of “Individual history of disease” was emerged only from experts’ interviews.

Conclusion

In the present study, the lay participants’ perception concerning BC risk factors was found to be a mixture of cultural beliefs and the scientific knowledge dispersed by the media, internet, and health services. Primary prevention approaches, including awareness of breast cancer risk factors, are required for women to make improved health-related choices.

Discriminatory Accuracy of the Gail Model for Breast Cancer Risk Assessment among Iranian Women

Background:

The Gail model is the most well-known tool for breast cancer risk assessment worldwide. Although it was validated in various Western populations, inconsistent results were reported from Asian populations. We used data from a large case-control study and evaluated the discriminatory accuracy of the Gail model for breast cancer risk assessment among the Iranian female population.

Methods:

We used data from 942 breast cancer patients and 975 healthy controls at the Cancer Institute of Iran, Tehran, Iran, in 2016. We refitted the Gail model to our case-control data (the IR-Gail model). We compared the discriminatory power of the IR-Gail with the original Gail model, using ROC curve analyses and estimation of the area under the ROC curve (AUC).

Results:

Except for the history of biopsies that showed an extremely high relative risk (OR=9.1), the observed ORs were similar to the estimates observed in Gail’s study. Incidence rates of breast cancer were extremely lower in Iran than in the USA, leading to a lower average absolute risk among the Iranian population (2.78, ±SD 2.45). The AUC was significantly improved after refitting the model, but it remained modest (0.636 vs. 0.627, ΔAUC = 0.009, bootstrapped P=0.008). We reported that the cut-point of 1.67 suggested in the Gail study did not discriminate between breast cancer patients and controls among the Iranian female population.

Conclusion:

Although the coefficients from the local study improved the discriminatory accuracy of the model, it remained modest. Cohort studies are warranted to evaluate the validity of the model for Iranian women.