Abstract C084: Cancer mortality patterns across three generations of Latinos in the US: The Multiethnic Cohort
Authors: Setiawan Veronica Wendy , Stern Mariana , Lim Unhee , Conti David , Haiman Christopher , Monroe Kristine 
Published: August 2020

Background: Latinos are the largest minority group in the United States. To provide better understanding of the influence of acculturation and environmental factors on cancer risks in Latinos, we examined cancer mortality patterns across 1st-generation (1°) immigrants, and 2nd- (2°) and 3rd-generation (3°) US-born Mexican Americans in the Multiethnic Cohort Study (MEC).

Methods: A total of 29,308 Latinos of Mexican origin aged 45-74 at cohort entry (1993-1996) were included in this analysis. Latino generations included 41% 1° Mexico-born immigrants, 28% 2° US-born with both parents Mexico-born, 14% 2° US-born with one parent US-born and one parent Mexico-born, and 17% 3° US-born with both parents US-born. Age-adjusted death rates were estimated across Latino generation. Cox models were used to estimate the relative risk (RR) and 95% confidence intervals (CI) for cancer mortality associated with generation, adjusted for risk factors for cancer mortality (e.g., obesity, smoking history, alcohol intake) at cohort baseline.

Results: During an average follow up of 17.7 years, 2,915 cancer deaths were identified. The highest cancer death rate (per 100,000) was observed among 3° US-born (age-adjusted rate=537), followed by 2° with one parent US-born (526), 2° with both parents Mexico-born (481) and lowest among 1° immigrants (381). After adjusting for education, lifestyle factors and preexisting illnesses, Latino generation was associated with cancer mortality risk (P trend&lt;0.0001). The risk for 3° US-born, 2° one parent US-born, and 2° both parents Mexico-born was significantly higher compared to 1° immigrants (RR=1.37 (95% CI: 1.21-1.54), 1.27 (1.12-1.44), and 1.20 (1.08-1.33), respectively). Restricting analyses to the MEC-Medicare enrollees, for whom we have data indicating they are living in the US and eligible for national health insurance coverage, yielded similar results. In specific cancer site analyses, there were associations between generation with lung (P trend=0.014), colorectal (P trend=0.004), liver (P trend=0.006) and possibly breast cancer (P trend=0.053). The risks of lung [RR=1.46 (1.09-1.97)], colorectal [RR=1.95 (1.28-2.95)] and liver cancer [RR=1.87 (1.22-2.85)] deaths were significantly higher among the 3° US-born compared to 1° Mexico-born immigrants. The risks of prostate, stomach, and pancreatic cancers were similar across generations.

Conclusions: In the MEC, Latinos experience an increase in lung, colorectal, liver, and possibly breast cancer mortality with increasing generation, indicating acculturation and environmental influences on these cancers. Identification of the contributing risk factors is important to reverse the trends of increasing mortality across offspring generations of Latinos living in the US.

Citation Format: Veronica Wendy Setiawan, Mariana Stern, Unhee Lim, David Conti, Christopher Haiman, Kristine Monroe. Cancer mortality patterns across three generations of Latinos in the US: The Multiethnic Cohort [abstract]. In: Proceedings of the Eleventh AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2018 Nov 2-5; New Orleans, LA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl):Abstract nr C084.