Persistent area socioeconomic disparities in U.S. incidence of cervical cancer, mortality, stage, and survival, 1975-2000

Abstract

Background: Temporal cervical cancer incidence and mortality patterns and ethnic disparities in patient survival and stage at diagnosis in relation to socioeconomic deprivation measures have not been well studied in the United States. The current article analyzed temporal area socioeconomic inequalities in U.S. cervical cancer incidence, mortality, stage, and survival.

Methods: County and census tract poverty and education variables from the 1990 census were linked to U.S. mortality and Surveillance, Epidemiology, and End Results cancer incidence data from 1975 to 2000. Age-adjusted incidence and mortality rates and 5-year cause-specific survival rates were calculated for each socioeconomic group and differences in rates were tested for statistical significance at the 0.05 level.

Results: Substantial area socioeconomic gradients in both incidence and mortality were observed, with inequalities in cervical cancer persisting against a backdrop of declining rates. Cervical cancer incidence and mortality rates increased with increasing poverty and decreasing education levels for the total population as well as for non-Hispanic white, black, American Indian, Asian/Pacific Islander, and Hispanic women. Patients in lower socioeconomic census tracts had significantly higher rates of late-stage cancer diagnosis and lower rates of cancer survival. Even after controlling for stage, significant differences in survival remained. The 5-year survival rate among women diagnosed with distant-stage cervical cancer was approximately 30% lower in low than in high socioeconomic census tracts.

Conclusions: Census-based socioeconomic measures such as area poverty and education levels could serve as important surveillance tools for monitoring temporal trends in cancer-related health inequalities and targeting interventions.