Kidney cancer incidence and mortality among American Indians and Alaska Natives in the United States, 1990-2009

Abstract

Objectives: We describe rates and trends in kidney cancer incidence and mortality and identify disparities between American Indian/Alaska Native (AI/AN) and White populations.

Methods: To improve identification of AI/AN race, incidence and mortality data were linked with Indian Health Service (IHS) patient records. Analysis focused on residents of IHS Contract Health Service Delivery Area counties; Hispanics were excluded. We calculated age-adjusted kidney cancer incidence (2001-2009) and death rates (1990-2009) by sex, age, and IHS region.

Results: AI/AN persons have a 1.6 times higher kidney cancer incidence and a 1.9 times higher kidney cancer death rate than Whites. Despite a significant decline in kidney cancer death rates for Whites (annual percentage change [APC] = -0.3; 95% confidence interval [CI] = -0.5, 0.0), death rates for AI/AN persons remained stable (APC = 0.4; 95% CI = -0.7, 1.5). Kidney cancer incidence rates rose more rapidly for AI/AN persons (APC = 3.5; 95% CI = 1.2, 5.8) than for Whites (APC = 2.1; 95% CI = 1.4, 2.8).

Conclusions: AI/AN individuals have greater risk of developing and dying of kidney cancers. Incidence rates have increased faster in AI/AN populations than in Whites. Death rates have decreased slightly in Whites but remained stable in AI/AN populations. Racial disparities in kidney cancer are widening.

FIGURE 1—

Annual age-adjusted kidney cancer incidence and death rates and trend lines among AI/AN persons and Whites in CHSDA counties. Note. AI/AN = American Indian/Alaska Native; APC = annual percentage change; CHSDA = Contract Health Service Delivery Areas. Analyses are limited to persons of non-Hispanic origin. AI/AN race is reported by NPCR and SEER registries, death certificates, or through linkage with the IHS patient registration database. APCs for death rates were based on rates that were age-adjusted to the 2000 US standard population (11 age groups, Census P25-1130²⁸) and estimated using joinpoint regression. APCs for incidence were based on rates that were age-adjusted to the 2000 US standard population (19 age groups, Census P25-1130) and were calculated with SEER*Stat. The following states and years of data were excluded because Hispanic origin was not collected on the death certificate: LA, 1990; NH, 1990–1992; and OK, 1990–1996. The following states and years of data were excluded because data were not collected or US Cancer Statistics standards were not met: MS, 2001–2002; TN, 2001–2002; VA, 2001; DC, 2002; and WI, 2009. Percentage regional coverage of AI/AN persons in CHSDA counties to AI/AN persons in all counties: Northern Plains = 64.8%; Alaska = 100%; Southern Plains = 76.3%; Southwest = 91.3%; Pacific Coast = 71.3%; and East = 18.2%; total US = 64.2%. Source. For mortality, AI/AN Mortality Database (1990–2009). For incidence, cancer registries in the Centers for Disease Control and Prevention’s NPCR, the National Cancer Institute’s SEER, or both. *P < .05 (2-tailed).