Few Providers Use Z-Codes to Document Social Determinants of Health

Z-codes were added as an element of ICD-10 to help healthcare organizations document and track social determinants of health in patients, but two new and unrelated studies in Health Affairs Scholar show that they’re barely being used.

The first study, completed by researchers from the NYU School of Global Public Health, showed that despite the utility of Z-codes, they aren’t being used for very diverse social determinants of health. More than half of the hospitals tested used the Z-code for housing insecurity, but other than that, the use of Z-codes was scant, the researchers found.

In the second study from experts at the Colorado School of Public Health and Johns Hopkins, researchers found that Z-code use was 50 percent more common in the Medicaid population than for commercially insured patients, and it was most commonly used in mental health or psychiatric settings.

Z-codes became a part of the healthcare coding process in response to the industry’s growing attention to social determinants of health (SDOH). Falling under the ICD-10 umbrella, Z-codes give healthcare providers a way to document an SDOH diagnosis for patients. This is helpful as more payment models incorporate quality measures related to identifying and addressing SDOH.

There are Z-codes for the following common SDOH: education and literacy, employment, occupational exposure, housing and economic circumstances, social environment, upbringing, primary support group, psychosocial circumstances, physical environment, and other psychosocial circumstances.

But despite the potential utility for Z-codes, the data shows they are barely being used. In the first study, the NYU researchers found that around 56 percent of the nearly 6,000 US hospitals included in the study used at least one Z-code on at least one patient per year, but Z-code type wasn’t very diverse.

The most common Z-code used during the study’s 2017-2021 assessment period was Z59, which relates to housing and economic circumstance, with 56 percent of the observed hospitals using this Z-code. Less than 10 percent of hospitals used another type of Z-code.

General medicine hospitals, teaching hospitals, those affiliated with bigger health systems, and those that themselves were of medium or large size were more likely to have used a Z-code, the researchers added.

“This raises questions on the preparedness and emphasis healthcare settings place on holistic understanding of SDOH,” the researchers said. “To bridge this gap, Hospitals may benefit from comprehensive training programs that emphasize the importance of all SDOH domains and for establishing robust systems and partnerships that can address the myriad of non-medical needs patients may present with beyond housing.”

The second study from the researchers at CU Anschutz and Johns Hopkins found something similar. Z-code use is dismally low, the researchers said, and there are differences in which types of patients get a Z-code in their medical record.

In an analysis of Z-codes by type, setting, and patient demographic, the researchers found that Z-code use was 50 percent greater among Medicaid patients than commercially insured patients. This could be because Medicaid patients are more likely to experience SDOH, although the data did not dive into that consideration.

Medicaid patients were more likely to receive Z-codes related to economic hardships, while commercially insured patients were more likely to get ones linked to social relationships.

There were also differences in where patients got a Z-code documented in their medical records. Mental health and psychiatric settings were the most common settings in which any patient might get a Z-code. However, Medicaid patients were more likely to get a Z-code in an inpatient setting, while commercially insured patients were more likely to get one in an outpatient setting.

Despite differences in Z-code use by patient demographic, the main issue at hand is low Z-code utilization, according to the study’s first author, Jason Gibbons, PhD, assistant professor and a health economist at the Colorado School of Public Health at CU Anschutz.

“To better serve a more diverse population, there’s a critical need for healthcare offices to identify and appropriately document social factors impacting a patient’s health,” Gibbons said in a statement. “However, when the system in place to track social factors is highly underutilized, it showcases a clear issue that needs to be addressed and we’re hoping our research can inform ways to do so.”

Gibbons and colleagues indicated that integrating Z-codes in certain quality payment models and 1115 waiver programs could compel more widespread use. Greater provider education will also be key, Gibbons added.