Women who don't turn up for their first breast screening appointment face a 40% higher long term risk of dying from breast cancer, mainly due to delayed detection, finds a study published by The BMJ today.
The researchers say targeting these women offers a critical opportunity to reduce breast cancer deaths at the population level.
Mammograms can detect breast cancer early, often before a lump can be felt, which improves the chances of successful treatment and survival.
Although a later stage breast cancer diagnosis is more frequent among women who did not attend their latest screening, the long term implications of earlier screening behaviours, particularly first screening participation, remain unclear.
To address this knowledge gap, researchers set out to investigate whether women who did not attend their first breast screening appointment have a long term risk of poor screening adherence and breast cancer outcomes.
Their findings are based on Swedish registry data for nearly half a million women who received their first screening invitation between 1991 and 2020 and were monitored for up to 25 years.
Measures included subsequent breast cancer screening behaviour, breast cancer rates (incidence), tumour characteristics, and breast cancer deaths.
After taking account of a range of social, economic, reproductive, and health-related factors, the results show that among women invited to their first mammography screening, almost a third (32%) did not participate.
These non-participants were persistently less likely to attend subsequent screenings and were more likely to be diagnosed with advanced stage breast cancer than participants.
Non-participation at first screening was also associated with a significantly higher risk of breast cancer death (9.9 v 7 per 1,000 women over 25 years).
In contrast, the 25 year breast cancer rate was similar between groups (7.8% participants vs 7.6% non-participants), suggesting that the higher deaths among first screening non-participants likely reflects delayed detection rather than increased incidence.
This is an observational study so no firm conclusions can be drawn about cause and effect and the authors acknowledge that other unmeasured factors may have influenced their results and that the findings may not apply to populations with different healthcare systems, screening intervals, or cultural attitudes toward preventive care.
Nevertheless, use of register data and extended follow-up allowed for a thorough analysis of long term breast cancer outcomes, and results were similar after additional analyses, suggesting that they withstand scrutiny.
As such, they say: "Our study shows that first screening non-participants represent a large population at an elevated risk of dying from breast cancer decades in advance. This increased mortality is modifiable and primarily attributed to late detection."
They add: "Targeted interventions are warranted to boost adherence to mammography screening and decrease the mortality risk for those who did not participate in the first screening."
This study highlights that the decision to attend that first appointment is far more than a short term health check—it is a long term investment in breast health and survival, say US researchers in a linked editorial.
The findings should enable clinicians to emphasize the enduring long term effect on mortality during their interactions with patients, and support maintaining public investment in mammography infrastructure.
"Ensuring that women are informed, supported, and empowered to participate in their first screening should be a shared goal across the healthcare system," they conclude.
