Abstract 885: Lower mortality among married cancer patients: How much of the effect is explained by socioeconomic and health insurance status
Authors: Gomez Scarlett L. , Canchola Alison , Hurley Susan , Clarke Christina A. , Cheng Iona , Keegan Theresa H. M. , Glaser Sally L. , Martinez Maria Elena 
Published: August 2015

Background: Cancer patients who are married at diagnosis have lower mortality than the unmarried. Although this effect has been attributed to increased social support among married patients, whether economic resources influence this association remains unclear.

Purpose: We assessed whether overall mortality differences between married and unmarried cancer patients is modified by neighborhood socioeconomic status (nSES) and mediated by health insurance status.

Methods: We studied patients newly diagnosed (first invasive primary) with one of the 10 most common causes of cancer deaths from 2000 through 2009 in California. Information on patient nSES (based on block-group- level Census 2000 or 2007-2011 American Community Survey data), insurance (primary and secondary payer source), demographic and tumor characteristics, and follow-up through 2012 were obtained from the California Cancer Registry. Using Cox proportional hazards regression, we estimated overall mortality [hazard ratio (HR)] associated with marital status among N = 377,932 males (194,216 deaths) and N = 378,447 females (175,414 deaths), stratified on stage and adjusting for age, race/ethnicity, cancer site, nSES, insurance status, and treatment.

Results: Prior to adjustment for insurance status, unmarried patients had higher overall mortality than married patients [HR (males) = 1.28 (1.27-1.29), HR (females) = 1.20 (1.19-1.21)]. This association was marginally stronger among patients from higher SES neighborhoods [HR (males) = 1.30 (1.28-1.32), HR (females) = 1.21 (1.20-1.23)] than from lower SES neighborhoods [HR (males) = 1.27 (1.26-1.29), HR (females) = 1.19 (1.18-1.21)] and only slightly lower after adjustment for insurance status. The magnitude of the associations varied by race/ethnicity and cancer site, with the largest marital status effect sizes seen for: high SES non-Hispanic White males with non-Hodgkin lymphoma [1.62 (1.52-1.73)], low SES Black males with pancreatic cancer [1.40 (1.20-1.63)], high SES Hispanic males with prostate cancer [1.50 (1.33-1.69)], high SES Asian males with pancreatic cancer [1.57 (1.28-1.92)], high SES non-Hispanic White females with breast cancer [1.34 (1.29-1.38)] or NHL [1.34 (1.24-1.44)], low SES Black females with NHL [1.43 (1.13-1.81)], and high SES Hispanic [1.44 (1.12-1.86)] and Asian [1.59 (1.24-2.05)] females with leukemia. The largest attenuation of HRs after adjustment for insurance was seen among Blacks, regardless of nSES [males: from 1.26 (1.22-1.30) to 1.20 (1.16-1.24), females: from 1.15 (1.11-1.20) to 1.10 (1.06-1.15)].

Conclusions: Neighborhood SES and insurance status had no considerable impact on the association between marital status and mortality after cancer diagnosis.

Citation Format: Scarlett L. Gomez, Alison Canchola, Susan Hurley, Christina A. Clarke, Iona Cheng, Theresa H. M. Keegan, Sally L. Glaser, Maria Elena Martinez. Lower mortality among married cancer patients: How much of the effect is explained by socioeconomic and health insurance status. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 885. doi:10.1158/1538-7445.AM2015-885