Are socio-economic inequalities in breast cancer survival explained by peri-diagnostic factors?

Abstract

Background Patients living in more deprived localities have lower cancer survival in England, but the role of individual health status at diagnosis and the utilisation of primary health care in explaining these differentials has not been widely considered. We set out to evaluate whether pre-existing individual health status at diagnosis and primary care consultation history (peri-diagnostic factors) could explain socio-economic differentials in survival amongst women diagnosed with breast cancer. Methods We conducted a retrospective cohort study of women aged 15–99 years diagnosed in England using linked routine data. Ecologically-derived measures of income deprivation were combined with individually-linked data from the English National Cancer Registry, Clinical Practice Research Datalink (CPRD) and Hospital Episodes Statistics (HES) databases. Smoking status, alcohol consumption, BMI, comorbidity, and consultation histories were derived for all patients. Time to breast surgery was derived for women diagnosed after 2005. We estimated net survival and modelled the excess hazard ratio of breast cancer death using flexible parametric models. We accounted for missing data using multiple imputation. Results Net survival was lower amongst more deprived women, with a single unit increase in deprivation quintile inferring a 4.4% (95% CI 1.4–8.8) increase in excess mortality. Peri-diagnostic co-variables varied by deprivation but did not explain the differentials in multivariable analyses. Conclusions These data show that socio-economic inequalities in survival cannot be explained by consultation history or by pre-existing individual health status, as measured in primary care. Differentials in the effectiveness of treatment, beyond those measuring the inclusion of breast surgery and the timing of surgery, should be considered as part of the wider effort to reduce inequalities in premature mortality.

Socio-economic inequalities in cancer survival: how do they translate into Number of Life-Years Lost?

“…Research has shown that cancer awareness, clinical (comorbidities) and tumour-related (tumour stage) factors can only explain part of the inequalities in England [ 18 – 20 ] and that more emphasis should be given to the observed variation in cancer screening uptake [ 21 – 23 ] and management of patients [ 24 – 26 ]. However, communication of these epidemiological findings with political forces and stakeholders has been suboptimal, evidenced by the lack of initiative to target inequalities in a more methodical fashion.…”

Piloting a novel cancer care pathway: socioeconomic background as a barrier to access

“…The literature in this area is inconclusive, with some previous research suggesting that presentation with cancer-alarm symptoms is not necessarily correlated with socioeconomic status and others suggesting lower socioeconomic status can be linked to delayed presentation. 15,16 Our findings suggest referrals to the pathway are affected in similar ways to other cancer pathways; however, a larger sample size is needed to study effects on time to diagnosis and treatment outcomes.…”

Disparities in Cancer-Related Avoidable Mortality by the Level of Area Deprivation in South Korea

“…Similarly, another study in Germany revealed significantly excess cancer-related avoidable mortality in the more deprived regions [24]. Deprivation was also positively associated with breast cancer survival in England, in which each unit increase in deprivation quintile was associated with an increase in excess mortality [25]. The results of our study make a significant contribution to the existing literature because our data obtained from the general population show that area deprivation levels may also be associated with cancer-related avoidable deaths in Korea.…”