Neighborhood Level Socioeconomic Disadvantage and Adherence to Guidelines for the Evaluation of Patients with Incidentally Detected Pulmonary Nodules

Background: The management of incidental pulmonary nodules is guided by recommendations set forth by the Fleischner Society. While most pulmonary nodules are benign, timely and evidence-based follow-up can reduce morbidity and mortality. There are known socioeconomic disparities for engagement with recommended cancer screenings, however it is unclear whether disparities exist for follow-up of incidentally detected pulmonary lesions.

Research question: Do patients residing in more socioeconomically deprived neighborhoods have reduced likelihood of adherence to guideline-recommended follow-up of incidentally detected pulmonary nodules?

Study design and methods: We assembled a retrospective cohort of 32,965 patients within a large, regional integrated healthcare system with a defined membership who had a pulmonary nodule ≤30mm identified on diagnostic CT between 2012 and 2016. Patients with prior history of malignancy were excluded. Participants were subsequently divided into quartiles utilizing the Neighborhood Deprivation Index as a metric for socioeconomic status. Adherence was ascertained utilizing ICD-9 or CPT coded imaging or biopsy to determine if follow-up was performed within an interval specified by 2005 Fleischner Society Guidelines (with a +/-33% margin of error), based on each patient's nodule characteristics. Negative binomial regression was performed to determine the association between neighborhood level deprivation and adherence to guideline-concordant care, with and without adjustment for plausible confounders.

Results: Only 49.6% of patients had follow-up imaging or other diagnostic procedure performed within the guideline-recommended timeframe. There was a 3% reduction in adherence to follow-up for patients residing in the most socioeconomically deprived neighborhood quartile (relative risk [RR]=0.97; 95% CI 0.94 to 1.0) compared with the least deprived quartile. Smoking status was also associated with worse adherence (former vs never, RR= 0.67; 95% CI 0.65 to 0.69) current vs never, RR= 0.73; 95% CI 0.70 to 0.76). Multi-morbidity, and CHF in particular, was associated with decreased adherence to guideline-recommended care (Charlson Comorbidity Index of 3 vs 0, RR:0.93; 95% CI 0.89 to 0.97; History of CHF, RR: 0.93; 95% CI 0.90 to 0.97).

Interpretation: In the context of poor adherence overall, patients residing in the most socioeconomically deprived neighborhoods were less likely to receive care in concordance with Fleischner Society recommendations for management of incidental pulmonary nodules.