FY 2019 ICD-10 Code Changes Overview

FY 2019 ICD-10 Code Changes Overview

Tune in to this monthly online coding column, facilitated by AHIMA’s coding experts, to learn about challenging areas and documentation opportunities for ICD-10-CM/PCS.

By now, everyone should be aware that the fiscal year (FY) 2019 ICD-10 code changes have been released. There are not as many changes this year as there have been in previous years. The total number of diagnosis code changes is 473, with 279 new codes and 194 revised and deactivated codes. There is also not a lot of change in the FY 2019 Official Guidelines for Coding and Reporting. Most of the guideline changes appear to be documentation that has been added for clarification purposes.

Although there are not many changes, a few of the changes are very interesting.

Chapter 21 of the Official Guidelines for Coding and Reporting states: BMI codes should only be assigned when the associated diagnosis (such as overweight or obesity) meets the definition of a reportable diagnosis (see Section III, Reporting Additional Diagnoses). Do not assign BMI codes during pregnancy. See Section I.B.14 for BMI documentation by clinicians other than the patient’s provider.

One could easily read too much into this or not enough. Let’s address the first part of the new text:

  • BMI codes should only be assigned when the associated diagnosis (such as overweight or obesity) meets the definition of a reportable diagnosis (see Section III, Reporting Additional Diagnoses).

In previous years the guidelines stated, “As with all other secondary diagnosis codes, the BMI codes should only be assigned when they meet the definition of a reportable diagnosis.” However, there was a long-standing issue of Coding Clinic (Third Quarter 2011 pg. 3-4) that stated:

“Individuals who are overweight, obese or morbidly obese are at an increased risk for certain medical conditions when compared to persons of normal weight. Therefore, these conditions are always clinically significant and reportable when documented by the provider. In addition, the body mass index (BMI) code meets the requirement for clinical significance when obesity is documented.”

It appears that this guidance no longer applies. External auditors around the country are cheering. Payers have had a long-standing history of denying claims despite Coding Clinic advice. Providers should look for more of these denials if coders are not educated.

  • Do not assign BMI codes during pregnancy.

This sounds very straightforward, but it brings some questions to mind. Is this to be applied to patients that were obese prior to pregnancy or patients that moved from obese to morbid obesity during pregnancy? What if the patient’s obesity meets the requirements of a reportable condition? Would the BMI still not be coded? This is interesting, considering there has been longstanding guidance stating that “it is the provider’s responsibility to state that the condition being treated is not affecting the pregnancy.” It appears that codes for the BMI should not be assigned during pregnancy regardless of the circumstances. It’s understood that the patient’s weight increases during pregnancy, resulting in an increased BMI. Regardless, is that not the patient’s current BMI? Obese women have a greater risk of pregnancy complication such as preeclampsia and gestational diabetes. Should we not capture the BMI for a more accurate clinical picture? Hopefully, there will be more explanation in an upcoming issue of Coding Clinic.

On to other interesting code changes: six codes were downgraded from the MCC list and added to the CC list. Three of these codes were related to encephalopathy and HIV disease (AIDS).

  • 40, Encephalopathy, unspecified and G93.49, Other encephalopathy were both downgraded from MCCs to CCs.

Encephalopathy has been a targeted diagnosis by many external auditors. It is usually denied when it is the only MCC on the claim. For discharges that take place on or after October 1, 2018, providers should expect to see a decrease in pre-pay denials related to encephalopathy. That is, unless it is the only CC on the claim. There may still be several years before the decrease is seen in retrospective denials.

  • B20, HIV disease (AIDS) has been downgraded from MCC to CC.

This has not been a targeted diagnosis in the past. However, there should not be any surprises if payers come up with some creative denial strategies related to sequencing to get claims out of the Major Diagnostic Category (MDC 25) DRGs and into a DRG where B20 will be a CC.


Elena Miller is the director of coding audit and education at a healthcare system.

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  1. I have worked on both sides of the fence. I have worked as both a RAC auditor and a commercial payer DRG Validator. Currently, I am responsible for denials management and see 100% of the DRG denials received by my health system. My post is in no way meant to be a jab at the coding professionals that are employed by the companies responsible for performing these audits. Again, I see 100% of the denials that are received by my health system from various companies and some are downright egregious. Providers are receiving denials that are in direct conflict with official coding guidance. Providers are receiving denials that are based on the payer’s clinical definitions rather than industry standards. Providers are receiving a disparate share of overpayment findings. I appreciate those payers that are making every effort to follow the official coding guidelines, but unfortunately, not all are.

  2. Ellen I’d like to thank you in your efforts to keep membership informed about upcoming changes for FY 2019. However, I am disappointed by the jabs you’re taking at skilled professionals responsible for data integrity and over payment identification. As professionals we are held to the highest standards including AHIMA’s Code of Ethics and are members in good standing with AHIMA. I believe this blog would be better served if it represented the interests of all membership regardless of coding focus.

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