Effect of individual and neighborhood socioeconomic status on oral cancer survival

Abstract

This population-based study investigated the relationship between individual and neighborhood socioeconomic status (SES) and oral cancer mortality. A population-based follow-up study was conducted of 3607 oral cancer patients (predominantly male) who were diagnosed between 2004 and 2005. Each patient was traced to death or for 2 years. Individual SES was defined by enrollee category. Neighborhood SES was defined by income, and numbers of doctors, and neighborhoods were grouped into advantaged and disadvantaged areas. The Cox proportional hazards model was used to compare the death-free survival rate between the different SES groups after adjusting for possible confounding and risk factors. In oral cancer patients aged below 65 years, death rates among those with low SES were highest in disadvantaged neighborhoods. After adjusting for patient characteristics (age, gender, Charlson Comorbidity Index Score, urbanization, and area of residence), tumor extent, treatment modalities (operation, adjuvant therapy), hospital characteristics (ownership, teaching level, caseload), and year of diagnosis, oral cancer patients with low individual SES in disadvantaged neighborhoods conferred a 1.46- to 1.64-fold higher risk for death, compared with patients with high individual SES in advantaged neighborhoods. No statistically significant difference was found in risk of death between different SES groups in patients aged 65 and above. Our findings indicate that oral cancer patients with low individual SES have the highest risk of mortality even under a universal health-care system. Public health strategies and welfare policies must continue to focus on this vulnerable group.