Coding And Guidance Changes Affect Sepsis Rates

Coding artifact may be contributing to the apparent rise in sepsis incidence and decline in mortality.

Changes in Centers for Medicare and Medicaid Services (CMS) guidance on the International Classification of Diseases, 9th Revision (ICD-9) coding and Medical Severity Diagnosis Related Group (MS-DRG) systems resulted in higher rates of sepsis diagnosis, according to a study published in Clinical Infectious Diseases.

Shruti K Gohil, MD, MPH, of the Division of Infectious Diseases and Health Policy Research Institute at the University of California, Irvine School of Medicine and colleagues performed a 10-year retrospective cohort study of sepsis-related hospitalizations in California between January 2000 and December 2010.

Using logistic regression to evaluate sepsis and mortality and segmented regression statistical methods to collect data on sepsis frequency, the researchers noted a threefold increase in sepsis diagnoses during this time period, from 21.1 cases to 59.9 per thousand patients admitted.

There was also a 2.8 fold increase reports of severe sepsis, which had the greatest increase present on admission (3.8 fold). Non-severe sepsis had doubled. Despite these numbers, researchers explained that yearly admissions had not changed. They also noted that sepsis-related mortality rates fell.

Based on baseline data from January 2000 to September 2003, post-CMS guidelines on sepsis coding from October 2003 to September 2007 and following the use of MS-DRG from October 2007 to December 2010, Dr Gohill and colleagues concluded that the guidance and policy changes were associated with the higher rates of sepsis.

“Sepsis rate increases were associated with introduction of CMS-issued guidance for new sepsis ICD-9 coding and MS-DRGs. Coding artifact (“up-capture” of less severely ill septic patients) may be contributing to the apparent rise in sepsis incidence and decline in mortality,” the researchers wrote. 

In an editorial commentary, Valerie C Cluzet, MD, of the Infectious Diseases Department at the University of Pennsylvania in Philadelphia acknowledged the importance of the study’s data, because, Dr Cluzet explained, it highlights how policy changes can have a profound effect on health outcomes like sepsis incidence and treatment. 

However, Dr Cluzet explained that while these data show that policy changes are associated with rising sepsis rates, “it is also important to note that the incidence of sepsis does appear to be rising, albeit likely at a slower rate than the current trends indicate” and that other causes may include “enhanced identification of sepsis (particularly on admission), improved identification and documentation through electronic health records, and increases in the aged population.”

Dr Cluzet noted some study limitations. For example, study participants were adults, leaving questions as to how the results would pertain to pediatric populations. Also, the results seen in California might not be transferrable to the rest of the country, Dr Cluzet noted, because of California’s large population and racial and ethnic diversity.

The accompanying editorial also highlighted the study’s data that nonwhites are more likely to be diagnosed with sepsis, and attributed this to a number of factors, including “differences in chronic disease burden (ie, higher incidence of chronic kidney disease and diabetes in nonwhites); differences in the immune response to infection, as genetic polymorphisms in proteins involved in the host response to infection have been found in patients of African descent; and social and environmental factors, such as receiving care at hospitals that provide poorer quality of care.”


1. Gohil SK, Cao C, Phelan M et al. Impact of policies on the rise in sepsis incidence, 2000–2010. Clin Infect Dis. 2016;62(6). 695-703. doi: 10.1093/cid/civ1019. Accessed March 23, 2016.

2. Cluzet VC, Lautenbach E. Editorial commentary: we are seeing more sepsis…. but are we seeing the whole picture? Clin Infect Dis. 2016;62(6). 704-706. doi: 10.1093/cid/civ1023. Accessed March 23, 2016.