# House value as an individual socioeconomic indicator for breast cancer survival and late-stage diagnosis: a population-based cohort study from Northern Ireland

## TL;DR

This study shows that house value is a better indicator of breast cancer outcomes than area-based deprivation, highlighting socioeconomic inequalities in Northern Ireland.

## Contribution

The study introduces house value as a more sensitive individual-level socioeconomic indicator for breast cancer outcomes compared to area-based measures.

## Key findings

- Lower house value was associated with a 60% higher mortality risk and more late-stage diagnoses.
- Area-based deprivation showed a 26% higher mortality risk but no significant difference in late-stage diagnosis.
- Individual-level house value demonstrated stronger associations with outcomes than area-level deprivation.

## Abstract

Socioeconomic inequalities in breast cancer survival persist in the UK. Area-based deprivation measures may underestimate socioeconomic effects by assigning average deprivation levels to all area inhabitants. This study investigated associations between house value (individual-level) and area-based deprivation with breast cancer outcomes in Northern Ireland.

Women diagnosed with breast cancer from 2011 to 2021 were identified using the Northern Ireland Cancer Registry. House value was determined from Valuation and Lands Agency property valuation data, and area-based deprivation from the Northern Ireland Multiple Deprivation Measure. The primary outcome was breast cancer-specific mortality. Secondary outcomes were stage at diagnosis and all-cause mortality. Cox regression models calculated adjusted hazard ratios (HR) and 95% confidence intervals (95% CIs) for mortality by house value category and deprivation, adjusting for confounders.

Among 12,766 women with breast cancer, women in the lowest versus highest house value category had a 60% increase in mortality (adjusted HR = 1.60 95% CI 1.34, 1.92; per 20 percentile decrease adjusted HR = 1.12 95% CI 1.08, 1.16) and were more likely diagnosed with stage 4 disease (7.5% versus 4.1%; P < 0.001). Women living in the most versus least deprived areas had a 26% increase in mortality (adjusted HR = 1.26 95% CI 1.08, 1.47; per 20 percentile decrease adjusted HR = 1.05 95% CI 1.01, 1.08) but had no difference in stage 4 disease (5.9% vs. 5.0%; P = 0.157).

Individual-level house value demonstrated stronger associations with breast cancer outcomes than area-level deprivation, suggesting it may serve as a more sensitive indicator for monitoring health inequalities in cancer.

The online version contains supplementary material available at 10.1007/s10549-026-07947-z.