Associations of household income with health-related quality of life following a colorectal cancer diagnosis varies with neighborhood socioeconomic status.

Robinson, Jamaica Rm; Phipps, Amanda I; Barrington, Wendy E; Hurvitz, Philip M; Sheppard, Lianne; Malen, Rachel C; Newcomb, Polly A

BACKGROUND Existing evidence indicates household income as a predictor of health-related quality of life (HRQoL) following a colorectal cancer (CRC) diagnosis. This association likely varies with neighborhood socioeconomic status (nSES), but evidence is limited. METHODS We included data from 1355 CRC survivors participating in the population-based Puget Sound Colorectal Cancer Cohort (PSCCC). Survivors reported current annual household income; we measured HRQoL via the Functional Assessment of Cancer Therapy - Colorectal (FACT-C) tool. Using neighborhood data summarized within a 1-km radial buffer of Census block group centroids, we constructed a multidimensional nSES index measure. We employed survivors' geocoded residential addresses to append nSES score for Census block group of residence. With linear general estimating equations clustered on survivor location, we evaluated associations of household income with differences in FACT-C mean score, overall and stratified by nSES. We used separate models to explore relationships for wellbeing subscales. RESULTS We found lower household income to be associated with clinically meaningful differences in overall FACT-C scores (<$30K: -13.6, 95% CI: -16.8, -10.4) and subscale wellbeing after a recent CRC diagnosis. Relationships were slightly greater in magnitude for survivors living in lower SES neighborhoods. CONCLUSION Our findings suggest that recently diagnosed lower income CRC survivors are likely to report lower HRQoL, and modestly more so in lower SES neighborhoods. IMPACT Findings from this work will aid future investigators' ability to further consider the contexts in which the income of CRC survivors can be leveraged as a means of improving HRQoL.