Social determinants of health coding among hospital visits made by adults with cancer.

58 Background: Social determinants of health (SDOH) impact clinical outcomes among patients diagnosed with cancer. In late 2015, ICD10 codes starting with the Z prefix, or “Z-codes”, were introduced to capture SDOH complexity, characterizing problems involving housing and finances, physical environment, and social environment. We examined comprehensive hospital visits from a regional health information exchange for the entire combined tumor registry from an academic medical center and county safety-net hospital. We analyzed Z-code uptake as patients visited over 80 hospitals and 21 health systems, for all payors including the uninsured. Methods: We identified incident cancers of adults aged 18 or older from the 2 tumor registries, diagnosed from 1/1/2015 – 12/31/2023, and linked them to all their hospital visits in the health information exchange. We characterized trends in Z-code entry (Z55 - Z65) and analyzed sociodemographic characteristics associated with Z-code entry from hospital visits, using Chi-squared and t-tests. Results: We identified 57,598 patients with at least one hospital discharge. Of these, 23.9% patients were from the county system, and 57.5% were at least 65 years old; 23.4% were of Black race. The primary payor at diagnosis included 8.0% Medicaid and 24.3% uninsured/charity care. Nearly one-quarter (24.4%) of patients had advanced-staged disease at diagnosis. The most common cancers were breast (15.7%), leukemia and lymphoma (12.6%), and lung (10.4%). The most common Z-codes were Z59: housing and economic circumstances (48.6% of all Z-codes) and Z63: problems with family circumstances (13.2%). Table 1 shows the proportion of hospital visits with a Z-code over time, reaching 11.3% of visits by 2023. For the study period, 4.7% of patients had at least one Z-code entered. Black patients were more likely to have a Z-code (vs non-Black, 7.2% v 4.9%; p < 0.001), as were uninsured patients (vs commercially or Medicare insured, 9.6% v 2.9%; p < 0.001) and patients with advanced Stage III or Stage IV disease (vs Stage I or Stage II, 29.8% v 24.1%, p < 0.001). County hospital visits were more likely to have a Z-code compared to non-county hospital visits (3.7% v 1.6%; p < 0.001). Conclusions: In a population-based sample of adults with cancer and their comprehensive hospital visits, Z-code use increased to over 11% of hospital visits by 2023. We detect a rise in Z-code entry in 2023, likely in preparation for the Centers for Medicare and Medicaid Services requirement for inpatient SDOH screening in January 2024. Overall, housing and financial problems were the most frequently documented needs. Proportion of hospital visits with associated Z-code entry from 2015 to 2023. Year of Hospital Visits Total Hospital Visits Percentage of Visits with Z-code (%) 2015 2,748 1.3 2016 20,460 1.1 2017 22,770 1.3 2018 23,564 1.4 2019 25,239 2.3 2020 22,290 2.3 2021 23,211 2.5 2022 22,222 3.2 2023 19,180 11.3