Association of Area Deprivation Index in Kidney Cancer Mortality

Socioeconomic status contributes to disparities in kidney cancer outcomes. We examined the association between Area Deprivation Index (ADI) and overall mortality (OM) and cancer-specific mortality (CSM) in a North American statewide cohort.

By using the Michigan Department of Health and Human Services database, we included patients diagnosed with renal cell carcinoma between 2004 and 2019. ADI was assigned based on residential census block group, ranked as a percentile of deprivation relative to the national level. Individuals were categorized into quartiles, based on national quartile value, where the fourth (ADI: 75-100) represented those in the most deprived areas. Cumulative incidence function was used to compare CSM and OM with ADI quartile. Competing-risk regression and Cox regression analysis tested the association of ADI on CSM and OM, respectively.

We included 9210 patients with a median age of 60 (IQR: 52-67) years. Among those, 35.6%, 31.2%, 25.4%, and 7.8% were from the fourth, third, second, and first ADI quartile, respectively. Compared with the first ADI quartile, those in the fourth were younger (median age: 59 vs 60) and diagnosed more often with clear cell and papillary renal cell carcinoma (respectively, 70% vs 67% and 23.1% vs 20.9%; all P < .0001). At 10 years, CSM hazard was 25.6% vs 26.4% (P = .02) and OM hazard was 60.7% vs 72.8% (P < .0001) for patients in the first vs fourth ADI quartiles. Multivariable analysis showed that, comparing with the first ADI quartile, patients in the second, third, and fourth had, respectively, 1.62-, 1.45-, and 1.38-fold higher CSM hazard (P = .03) and 1.32-, 1.41-, and 1.58-fold higher OM hazard (P < .001).

The ADI was significantly associated with kidney cancer outcomes, with patients in more deprived areas exhibiting a higher mortality risk.