Jewish ethnicity and pancreatic cancer mortality in a large U.S. cohort.

BACKGROUND: An association between Jewish ethnicity and pancreatic cancer risk was suggested by analyses comparing pancreatic cancer mortality rates between Jews and non-Jews in New York in the 1950s. These analyses lacked information on potential confounding factors and the association between Jewish ethnicity and pancreatic cancer has not been examined in any contemporary U.S. population or in any cohort study. METHODS: We examined the association between Jewish ethnicity and pancreatic cancer mortality among approximately 1 million participants in the Cancer Prevention Study II cohort. Participants completed a questionnaire at enrollment in 1982 which included information on religion, smoking, obesity, and diabetes. During follow-up through 2006, there were 6,727 pancreatic cancer deaths, including 480 among Jewish participants. Proportional hazards modeling was used to calculate multivariable rate ratios (RR). RESULTS: After adjusting for age, sex, smoking, body mass index, and diabetes, pancreatic cancer mortality was higher among Jewish participants than among non-Jewish whites (RR = 1.43; 95% CI, 1.30-1.57). In analyses by birthplace, RRs were 1.59 (95% CI, 1.31-1.93) for North American-born Jews with North American-born parents, 1.43 (95% CI, 1.27-1.61) for North American-born Jews with 1 or more parents born outside North America, and 1.03 (0.73, 1.44) for Jews born outside North America (P(heterogeneity) = 0.07). CONCLUSIONS: These results support a higher risk of developing pancreatic cancer among U.S. Jews that is not explained by established risk factors. IMPACT: Future studies may clarify the role of specific environmental or genetic factors responsible for higher risk among U.S. Jews.