Poster #1 - Understanding Immigrants’ Cancer Mortality Advantage: Contributions of Health Insurance and Age at Diagnosis

• In Event: Friday Poster Reception

Abstract

Background. Immigrants in the United States have lower cancer mortality than their US-born counterparts, a pattern consistent with the broader "healthy immigrant effect." Yet the mechanisms underlying this advantage remain poorly understood. Immigrants, particularly non-citizens, face substantial structural disadvantage, including high rates of uninsurance and limited access to care, raising the question of whether their mortality advantage reflects genuine health selection or is partly explained by more favorable diagnostic and insurance circumstances. 

 Purpose. We formally decompose immigrant–US-born cancer mortality gaps into contributions from differential exposure to early/late age at diagnosis and insurance coverage, and differential mortality risk associated with these factors across immigration groups.  

Data. We analyzed the 2000–2018 National Health Interview Survey (NHIS) prospectively linked to the National Death Index (NDI). Our sample included 525,056 adults followed for a median of 9.25 years (IQR: 5–14) through December 31, 2019. Immigration status was classified as US-born (n = 436,638), naturalized citizens (n = 41,491), and non-citizens (n = 46,927).  Methods. We modeled cause-specific cancer mortality using Poisson regression with person-time offsets. We conducted two pairwise econometric decompositions: naturalized citizens versus US-born and non-citizens versus US-born, partitioning mortality gaps into differential exposure (ΔE) and differential risk (ΔR) components for age at cancer diagnosis and insurance coverage, adjusting for demographic and health confounders. In secondary analyses, we estimated contributions stratified by sex and also among cancer survivors diagnosed at baseline.  

Results. Cancer mortality was highest among US-born adults (2.77 per 1,000 person-years [PYs]), followed by naturalized citizens (2.08) and non-citizens (0.97). Consequently, the non-citizen-US-born mortality gap (−1.79 cases/1,000 PY) was much larger than the naturalized-US-born gap (−0.68 cases/1,000 PY). Non-citizens were far more likely to be uninsured than US-born adults (46.3% vs. 12.5%) and were less likely to have been diagnosed with cancer at baseline (1.6% vs. 8.8%). Among those diagnosed, non-citizens were diagnosed at younger ages on average. Consistent with these compositional differences, stratified models revealed that older age at diagnosis was associated with progressively higher mortality among US-born adults, whereas immigrants, younger age groups carried relatively higher mortality risk. Younger age at diagnosis among non-citizens accounted for approximately 11.46% of the gap. Notably, private insurance conferred a mortality benefit only for US-born adults; equalizing the returns to private insurance across groups would further reduce non-citizen cancer mortality by 0.50 deaths per 1,000 PYs. Estimated contributions to the naturalized-US-born gap were rather imprecise. Sex-stratified decompositions revealed similar patterns. Among cancer survivors, although the mortality gaps were larger, only age at diagnosis partially explained the naturalized-US-born gap.   

Conclusions. Age at diagnosis and insurance together explained only a modest share of immigrants’ cancer mortality advantage, with underlying health selection potentially continuing as the dominant driver. Yet, our analysis suggests that policies undermining immigrants’ access to protective insurance coverage may threaten their access to cancer care and worsen their survival. Further research should further unpack these mechanisms and heterogeneity by finer legal status categories.

Authors

• Eslam Abousamra, CUNY Graduate Center
  Presenting Author

• Mustafa Hussein, CUNY School of Public Health
  Non-Presenting Co-Author