Breast cancer care of Mexican American women in high poverty California neighborhoods: Protective effects of social and financial capital, including health insurance, in barrios

Objectives. We examined health insurance mediation of Mexican American (MA) non-Hispanic white (NHW) disparities on breast cancer care and survival. Based on social capital and barrio advantage theories, we hypothesized a 3-way ethnicity by poverty by health insurance interaction, that is, that 2-way poverty by health insurance interaction effects would differ between ethnic groups. Methods. We analyzed registry data for 303 MA and 3,611 NHW women diagnosed between 1996 and 2000 and followed until 2011. Socioeconomic data were obtained from the 2000 census to categorize neighborhood poverty: high (> 30% poor), middle and low (< 5% poor). Barrios were neighborhoods where 50% or more of the residents were MA. Primary health insurers were Medicaid, Medicare, private or none. Results. MA-NHW diagnostic, treatment and survival disparities were completely mediated by the main and interacting effects of health insurance. Advantages of health insurance were largest in low poverty neighborhoods among NHW women while among MA women they were, paradoxically, largest in high poverty, MA barrios. Advantages of being privately insured were observed for all, but were particularly pronounced among MA women who resided in barrios. Medicare seemed additionally instrumental for NHW women and Medicaid for MA women. Conclusion. These findings are consistent with the theory that more facilitative social and financial capital is available to MA women in barrios and to NHW women in more affluent neighborhoods. It is there that each respective group of women is probably best able to absorb the indirect and direct, but uncovered, costs of breast cancer care.