Cancer survival in New South Wales, Australia: socioeconomic disparities remain despite overall improvements

Abstract

BackgroundDisparities in cancer survival by socioeconomic status have been reported previously in Australia. We investigated whether those disparities have changed over time.MethodsWe used population-based cancer registry data for 377,493 patients diagnosed with one of 10 major cancers in New South Wales (NSW), Australia. Patients were assigned to an area-based measure of socioeconomic status. Five-year relative survival was estimated for each socioeconomic quintile in each ‘at risk’ period (1996–2000 and 2004–2008) for the 10 individual cancers. Poisson-regression modelling was used to adjust for several prognostic factors. The relative excess risk of death by socioeconomic quintile derived from this modelling was compared over time.ResultsAlthough survival increased over time for most individual cancers, Poisson-regression models indicated that socioeconomic disparities continued to exist in the recent period. Significant socioeconomic disparities were observed for stomach, colorectal, liver, lung, breast and prostate cancer in 1996–2000 and remained so for 2004–2008, while significant disparities emerged for cervical and uterus cancer in 2004–2008 (although the interaction between period and socioeconomic status was not significant). About 13.4 % of deaths attributable to a diagnosis of cancer could have been postponed if this socioeconomic disparity was eliminated.ConclusionWhile recent health and social policies in NSW have accompanied an increase in cancer survival overall, they have not been associated with a reduction in socioeconomic inequalities.Electronic supplementary materialThe online version of this article (doi:10.1186/s12885-016-2065-z) contains supplementary material, which is available to authorized users.

Socioeconomic environment and disparities in cancer survival for 19 solid tumor sites: An analysis of the French Network of Cancer Registries (FRANCIM) data

“…Previous studies investigating the influence of social environment on cancer survival for several solid tumor sites with comparable methodology (i.e. population‐based registries data, ecological deprivation index, net survival) also showed lower survival among patients living in the most deprived environments compared to those living in the least deprived ones, for most cancer sites . More broadly, all studies investigating social inequalities in cancer survival worldwide have reported lower survival among the most deprived for a large majority of cancer sites, with no significant inverse association .…”

“…However, some of the potential explanations mentioned above as well as previous research suggest that not only individual but also contextual and environmental factors might contribute to social inequalities in cancer survival. Indeed, several population‐based studies from different countries have shown that patients living in the most deprived areas experienced lower survival rates than those living in the most affluent ones, for most of the cancer sites …”

Socioeconomic and Racial/Ethnic Disparities in Cancer Mortality, Incidence, and Survival in the United States, 1950–2014: Over Six Decades of Changing Patterns and Widening Inequalities

“…An approximately twofold higher cervical cancer mortality was found among women in low- than high-SES groups in a study that compared inequalities in various low/middle income countries, North America, and Europe, although the magnitude of socioeconomic inequalities was greater in North America than in Europe [43, 46, 47]. Consistent with the US pattern, cancer survival rates have decreased consistently by deprivation levels in the UK, Australia, and New Zealand [36, 48, 49]. …”

Socioeconomic inequality in cancer survival – changes over time. A population-based study, Denmark, 1987–2013

“…A populationbased study from Osaka, Japan found no obvious changes in five-year net survival between patients living in affluent vs. deprived areas in the period 1993-2004, except for a modest increase in inequality for lung cancer survival among men [9]. In a recent population-based study from New South Wales, Australia, inequality in relative survival by area-based deprivation was either stable or increasing in the 10 most common cancers between 1996 and 2008 [8]. Our study, based on individual-level measure and hence more precise measurement of socioeconomic position, reveal a rather stable survival gap between richest and poorest, that is, breast, lung or kidney cancer patients in Denmark and even a tendency to a slight decrease in survival gap among prostate cancer and NHL patients; however, we still observe that for many common cancers the gap has widened considerably over the past decades.…”

“…Only few studies that have investigated socioeconomic inequality on cancer survival over time. These studies have either shown no change in disparities or a widening of disparities for several major cancers [8][9][10][11][12][13]. In Denmark, cancer survival rates have been lower than many other Western countries through several decades.…”