Adult cystic fibrosis (CF) patients of low socioeconomic status (SES) have a greater chance of not being accepted for lung transplant after undergoing initial evaluation, according to a new study.

"While earlier studies have indicated that SES does not affect access to care for , ours is the first study to examine the relationship between SES and access to in these patients," said lead author Bradley S. Quon, MD, MSc, MBA, of the University of Washington Medical Center in Seattle. "In our nationally representative sample of adult patients with CF, we found that multiple indicators of SES were associated with greater odds of not being accepted for transplant."

The findings were published online ahead of print publication in the 's American Journal of Respiratory and .

The study included 2,167 adult from the CF Foundation Patient registry, all of whom underwent their first lung transplant evaluation as an adult between January 1, 2001, and December 31, 2009. Receipt of Medicaid insurance was used as the primary indicator of SES status. The outcome of interest was acceptance onto the waiting list for lung transplant after initial evaluation. Patients who were either declined or deferred were classified as not accepted, and an additional sensitivity analysis was performed based on the final decision of whether a patient was accepted or declined at the end of the study period.

Of the 2,167 patients included in the study, 1009 (47%) received Medicaid. Compared to non-, the odds of not being accepted for lung transplant was 1.56 fold higher among Medicaid recipients. This relationship was independent of differences in disease severity, demographic factors, contraindications to lung transplant, and use of the lung allocation score.

Other indicators of low SES, including residing in lower income zip codes and not graduating from high school, were also independently associated with not being accepted for lung transplant after undergoing initial evaluation.

The study had a few limitations, including the use of Medicaid and other indicators as proxies for SES status. Furthermore, inadequate social support and poor adherence are key determinants of transplant eligibility. Although the authors attempted to account for these factors in their analysis, incomplete adjustment for these variables may at least partially explain why low SES was associated with not being accepted for lung transplant.

"The results of our study are concerning, as the effects of SES status on access to lung transplant appear to be unrelated to differences in or potential contraindications," said Dr. Quon. "More research is needed to explore the factors associated with Medicaid status that negatively impact lung transplant access and to assess whether these disparities are seen in other pre-lung transplant patient populations."