Prostate cancer incidence and survival in relation to education (United States).

INTRODUCTION

There are few data on prostate cancer incidence and survival in relation to socioeconomic status in the 1990s, after the introduction of prostate specific Antigen (PSA) testing.

MATERIALS AND METHODS

We studied the relation of education to prostate cancer incidence and survival in the Cancer Prevention Study II (CPS-II) Nutrition Cohort. Participants provided questionnaire data on diet, medical history, education, and PSA testing. We followed 72,449 men from 1992-1999 for cancer incidence (4279 incident cases), and through 2000 for survival (158 prostate cancer deaths among incident cases).

RESULTS

Multivariate-adjusted rate ratios (RRs) were calculated using Cox proportional hazards models. Self-reported (PSA) tests were more common among the more highly educated. Men with at least a college education had a 15-19% higher prostate cancer incidence than those with a high school education or less, but this association was limited to localized cancers and was attenuated by adjustment for PSA testing. Survival analysis among incident prostate cancer cases adjusted for stage and grade at diagnosis showed much lower prostate cancer mortality for men with at least a high school education compared to those with less than a high school education (RR = 0.49, 95% CI = 0.32-0.76).

CONCLUSIONS

This study suggests that higher education is associated with slightly increased incidence of prostate cancer, at least partly due to greater use of PSA screening and a greater detection of localized tumors among more highly educated men. The much lower survival rates from prostate cancer among those with less than a high school education cannot be explained by available data and may reflect disparities in treatment. In 1999, 27% of US males over age 55 and older had less than a high school education.