Area Deprivation Index and Melanoma Thickness in Veterans.

Importance: The US Veterans Health Administration (VHA) provides comprehensive medical care for enrolled veterans. Differences in melanoma diagnosis, associated with individual-level factors, have been previously published. The area deprivation index (ADI) ranks a neighborhood's level of deprivation and can inform whether the characteristics of a patient's area of residence can contribute to delayed diagnosis, measured by melanoma thickness.

Objective: To evaluate if neighborhood deprivation is associated with thicker (greater than 2 mm) cutaneous melanoma diagnosis after controlling for individual-level characteristics in the US veteran population.

Design, setting, and participants: This national cohort study used data from the US Veterans Eligibility Trends and Statistics database, the Veterans Affairs Cancer Registry, and veterans' electronic health care records. Veterans enrolled at the VHA who were diagnosed with melanoma from October 1, 2013, to December 31, 2019, were included. Data analysis conducted from September 2023 to July 2024.

Exposures: Quintiles of ranked neighborhood deprivation measured by the nationwide ADI.

Main outcomes and measures: Generalized Poisson models were used to calculate the risk of a thick cutaneous melanoma diagnosis, defined by the American Joint Committee on Cancer Staging Manual eighth edition staging as a Breslow thickness greater than 2 mm (ie, T3 to T4 disease).

Results: Of 7249 veterans with a melanoma diagnosis included in the study, 6988 (96.4%) were male, and the mean (SD) age was 68.9 (12.2) years. A total of 856 (11.8%) lived in the least deprived neighborhoods (quintile 1: ADI of 1-20) and 1205 (16.6%) lived in the most deprived neighborhoods (quintile 5: ADI of 81-100) nationwide. The risk of thicker melanoma at diagnosis increased with measured deprivation in the neighborhood. There was a 33% increased risk of thicker melanoma (greater than 2 mm) in veterans in quintile 5 compared with those in quintile 1 of ADI (adjusted risk ratio, 1.33; 95% CI, 1.05-1.68).

Conclusions and relevance: In this national cohort study of US veterans with melanoma, neighborhood-level deprivation at time of diagnosis was independently associated with thicker melanoma at diagnosis after controlling for individual-level factors and tumor characteristics. These findings underscore the significant association between neighborhood deprivation and melanoma diagnosis.