PURPOSE: Although there are few confirmed risk factors for prostate cancer (PCa), mortality rates are known to vary geographically across the United States. PCa mortality is higher among black and younger white men in a band of states spanning from Washington DC to Louisiana (the "PCa belt"). This study assessed the associations of birth and adult residence in the PCa belt with PCa mortality among black and white men and trends in these associations over time. METHODS: PCa-specific mortality rates in 1980, 1990, and 2000 for black and white men born in the continental US, aged 40-89, were calculated by linking national mortality records with population data based on birth state, state of residence at the census, race, and age. PCa belt (Washington DC, Virginia, North Carolina, South Carolina, Georgia, Mississippi, Alabama, and Louisiana) birth was cross-classified against PCa belt adult residence. RESULTS: Black men born in the PCa belt had elevated PCa mortality in 1980, 1990, and 2000. Associations were independent of adult residence in the PCa belt. For example, in 2000, black men aged 65-89 who were born in the PCa belt but no longer lived there in adulthood had an odds ratio of 1.19 (1.14-1.24) for PCa mortality compared to black men born and residing outside the PCa belt. The PCa belt was not associated with PCa mortality among whites. CONCLUSIONS: Geographically patterned childhood exposures, for example, differences in social or environmental conditions, or behavioral norms, may influence PCa mortality.
PURPOSE: Although there are few confirmed risk factors for prostate cancer (PCa), mortality rates are known to vary geographically across the United States. PCa mortality is higher among black and younger white men in a band of states spanning from Washington DC to Louisiana (the "PCa belt"). This study assessed the associations of birth and adult residence in the PCa belt with PCa mortality among black and white men and trends in these associations over time. METHODS: PCa-specific mortality rates in 1980, 1990, and 2000 for black and white men born in the continental US, aged 40-89, were calculated by linking national mortality records with population data based on birth state, state of residence at the census, race, and age. PCa belt (Washington DC, Virginia, North Carolina, South Carolina, Georgia, Mississippi, Alabama, and Louisiana) birth was cross-classified against PCa belt adult residence. RESULTS: Black men born in the PCa belt had elevated PCa mortality in 1980, 1990, and 2000. Associations were independent of adult residence in the PCa belt. For example, in 2000, black men aged 65-89 who were born in the PCa belt but no longer lived there in adulthood had an odds ratio of 1.19 (1.14-1.24) for PCa mortality compared to black men born and residing outside the PCa belt. The PCa belt was not associated with PCa mortality among whites. CONCLUSIONS: Geographically patterned childhood exposures, for example, differences in social or environmental conditions, or behavioral norms, may influence PCa mortality.