New Delhi, Dec 20 : A new study conducted by scientists at the Indian Council of Medical Research (ICMR) has decoded the specific risk factors for breast cancer among women in India.

Breast Cancer is among the top three cancers amongst women in India. The incidence of breast cancers in the country is expected to rise by about 5.6â?¯per cent annually, translating to an estimated increase of 0.05 million new cases per year.

The team from ICMRâ??s National Centre for Disease Informatics and Research (NCDIR), Bengaluru, conducted a systematic review and meta-analysis on 31 studies covering a total of 27,925 participants, with 45â??per cent being diagnosed with breast cancer.

The findings, published in the journal Cancer Epidemiology, showed that â??reproductive timing, hormonal exposure, central obesity, and family history influence breast cancer risk primarily among Indian womenâ??.

"Women with late menopause (more than 50years), first pregnancy after 30 years of age, higher age at marriage, multiple abortions and central obesity (with waist-to-hip ratio more than 85 cm) are at significant risk," the researchers said in the paper.

Among lifestyle factors, poor sleep quality, irregular sleep patterns, sleeping in a lighted room, and elevated stress levels were also positively associated with risk in individual studies. In contrast, higher levels of physical activity showed an inverse association.

The analysis found that women over 50 years had a three-fold higher risk, and women aged 35-50 years had a 1.63-fold increase in risk, highlighting the importance of early screening for women in their forties.

However, variations in age group classifications across studies may explain the observed heterogeneity. In high-income countries, breast cancer incidence rises significantly after the age of 50, with the majority of cases occurring in postmenopausal women.

In contrast, India exhibits a relatively higher incidence of breast cancer in younger women, typically between their 40s and 50s.

"Genetic susceptibility, earlier reproductive transitions, and distinct lifestyle factors may contribute to this disparity. These findings highlight the importance of early screening programmes for women in this age group to enable timely detection and intervention," said the researchers led by Saravanan Vijayakumar from the ICMR-NCDIR, in the paper.

The study stressed that it is important to consider low BMI as a potential risk factor for breast cancer prognosis and treatment outcomes, as these findings highlight.

As India has a high prevalence of abdominal obesity, lifestyle interventions aimed at reducing waist circumference may be beneficial for preventing breast cancer.

Notably, the review also highlighted the critical need for large, extensive, population-based prospective cohort studies in India to define breast cancer prevention and early detection strategies with greater precision.

/IANS