Construction of an environmental quality index for public health research

Association between the Environmental Quality Index and Textbook Outcomes Among Medicare Beneficiaries Undergoing Surgery for Early-Stage Pancreatic Adenocarcinoma

BACKGROUND

Access to high-quality cancer care is affected by environmental exposures and structural inequities. This study sought to investigate the association between the environmental quality index (EQI) and achievement of textbook outcomes (TO) among Medicare beneficiaries over the age of 65 who underwent surgical resection for early-stage pancreatic adenocarcinoma (PDAC).

METHODS

Patients diagnosed with early-stage PDAC from 2004 to 2015 were identified using the SEER-Medicare database and combined with the US Environmental Protection Agency's EQI data. High EQI category indicated poor environmental quality, whereas low EQI indicated better environmental conditions.

RESULTS

A total of 5,310 patients were included, of which 45.0% (n = 2,387) patients achieved TO. Median age was 73 years and more than half were female (n = 2,807, 52.9%), married (n = 3,280, 61.8%), and resided in the Western region of the US (n = 2,712, 51.1%). On multivariable analysis, patients residing in moderate and high EQI counties were less likely to achieve a TO (referent: low EQI; moderate EQI: OR 0.66, 95% CI 0.46-0.95; high EQI: OR 0.65, 95% CI 0.45-0.94; p < 0.05). Increasing age (OR 0.98, 95%CI 0.97-0.99), racial minorities (OR 0.73, 95% CI 0.63-0.85), having a Charlson co-morbidity index > 2 (OR 0.54, 95%CI 0.47-0.61) and stage II disease (OR 0.82, 95%CI 0.71-0.96) were also associated with not achieving a TO (all p < 0.001).

CONCLUSION

Older Medicare patients residing in moderate or high EQI counties were less likely to achieve an "optimal" TO after surgery. These results demonstrate that environmental factors may drive post-operative outcomes among patients with PDAC.