Educational inequalities in gastric cancer incidence and mortality, 1996-2015: a population-based study in Quito-Ecuador.

OBJECTIVE

To assess trends in educational inequalities in gastric cancer (GC) incidence and mortality in Quito, Ecuador, from 1996 to 2015.

METHODS

Using data available from the population-based cancer registry of Quito, age-specific standardised incidence and mortality rates for GC were calculated by educational level and sex. Using robust Poisson regression models, rate ratios, relative index of inequality (RII) and the slope index of inequality (SII) in incidence and mortality by educational level were estimated. Joinpoint regression analysis was performed to estimate the average annual percentage change.

RESULTS

The risk of developing GC among the less educated was substantially greater than among the most educated in both men and women, being around double the risk in relative terms (RIIwomen =2.1; 95% CI: 1.9, 2.3; RIImen = 1.7; 95% CI: 1.5, 1.8) and representing 14-15 cases per 100,000 person-years more cases in the lowest versus the highest educational levels (SIIwomen = 14.2; 95% CI: 12.2, 16.2; SIImen = 14.5; 95% CI: 12.0, 17.1). The differences were slightly greater for mortality.

DISCUSSION: Strong educational inequalities in GC incidence and mortality rates in Quito were observed. Efforts to target specific strategies among individuals with low education may help to ameliorate socioeconomic disparities in cancer incidence and mortality.