by Denise Wilson, RN, MS, RRT, Vice President, Clinical Appeal Services, Intersect Healthcare

Reproduced with permission of ACPA

A large national insurance carrier, offering managed Medicaid plans, recently denied the inclusion of ICD-10-CM codes Z68.41, body mass index (BMI) 40.0-44.9, and E66.01, morbid obesity due to excess calories, as secondary diagnoses on an inpatient claim for a large health system in Tennessee. The deletion of said codes resulted in a down coding of the originally billed DRG 086, Traumatic stupor & coma, coma <1 hr w CC to DRG 087, Traumatic stupor & coma, coma <1 hr w/o CC/MCC. The down coding resulted in a loss of dollars in the amount of $1,717 in reduced payment for the provider hospital.

The Back Story. A 61 year-old patient on aspirin and Plavix presented to the hospital emergency department after falling at home and suffering a severe headache immediately after. The CT indicated multiple areas of subarachnoid hemorrhage. The patient was declared a trauma and admitted to the ICU. A Neurology consult confirmed the diagnosis of subarachnoid hemorrhage. Fortunately, the patient’s hospital course was uneventful and the patient was able to be discharged home after a few days.

As the provider coded the chart for billing, codes that were included as secondary diagnoses were ICD-10-CM codes Z68.41, body mass index (BMI) 40.0-44.9, and E66.01, morbid obesity due to excess calories. After all, this patient’s body weight as recorded on the bed scale was 123.1 kg and the patient’s height as reported by the patient was 170.1 cm for a calculated BMI of 42.5 (click here for the page). The treating physician included the diagnosis of morbid obesity in the medical history section of the patient’s history and physical.

Coding guidelines in place at the time of the claim submission were as such:

“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.” Clinical Significance of Obesity, Coding Clinic, Third Quarter 2011, p. 4

So, imagine the provider’s surprise when the payer denied payment of the ICD-10-CM codes for body mass index 40.0-44 and morbid obesity. How could a payer deny these codes when they are clearly substantiated in the medical record and there is a Coding Clinic guideline from 2011 that tells us that these conditions are always (not sometimes, but always) clinically significant and reportable when documented by the provider?

Yes, up until October of 2016 there was some conflicting information between Official Coding Guidelines and Coding Clinic where the Official Coding Guidelines stated “As with all other secondary diagnosis codes, the BMI codes should only be assigned when they meet the definition of a reportable additional diagnosis (see Section III, Reporting Additional Diagnoses).” That discrepancy was corrected in the Coding Clinic, Fourth Quarter 2016: Page 118, when the requirement of meeting the definition of a reportable additional diagnosis was removed from the Official Coding Guidelines. That change went into effect October 1, 2016. Therefore, this payer used an illegitimate reason for upholding the denial stating that the morbid obesity and increased BMI did not complicate the hospital stay (payer-speak for stating the diagnoses did not meet the requirements for reporting additional diagnoses).

But that’s not the worst of it. The story gets more interesting. The provider appealed the denial stating that the payer’s allegation is incorrect and in conflict with the 2011 Coding Clinic. Unfortunately, the payer was not in agreement with the provider clearly pointing out the error in the payer’s ways and upheld the denial stating that, “per coding guidelines, diagnoses that have no impact on patient care during the hospital stay are not reported even when they are present. (Coding Handbook 2016, page 34.)” The payer apparently believed this statement from the Coding Handbook took precedence over the Coding Clinic specific to Obesity and BMI.

On to Round Three. Fortunately, in the state where this occurred, the provider had the option to appeal outside of the payer’s purview to an independent reviewer in the form of the state’s Oversight Division. Finally, an opportunity to explain the reasoning behind the inclusion of stated codes to someone outside of the payer who should have the knowledge and understanding of the Coding Clinic that clearly states that Obesity and BMI are always clinically significant and reportable (coded) when documented by the provider.

But, wait. The story begins to move from interesting to very strange. The independent reviewer in the form of the state Oversight Division upheld the denial again. The stated reason? “The reported BMI was not based on actual measured height but on the patient’s reported height, and thus was not a reliable measure.” Yes, both the trauma team in the ED and the nurses in the ICU failed to have the patient with the subarachnoid hemorrhage stand up to get an accurate measurement of height. Instead, they relied on the patient’s reported height in their calculation of the BMI. The independent reviewer, who was the medical director at the Medicaid agency, claimed that people “of this person’s age tend to over report their height.”

The independent reviewer supported the unreliability of using the patient’s reported height in the BMI calculation by citing two studies:

1. Merrill RM, Richardson JS. Validity of Self-Reported Height, Weight, and Body Mass Index: Findings from the National Health and Nutrition Examination Survey, 2001-2006. Preventing Chronic Disease. 2009;6(4}:A121.
2. Magnusson K, Haugen IK, Osteras N, Nordsletten L, Natvig B, Hagen KB. The validity of self-reported body mass index in a population-based osteoarthritis study. BMC Musculoskeletal Disorders. 2014;15:442. doi:10.1186/1471-2474-15-442.

From my review of the studies above, the first study concluded that “men overreported their height by 1.22 cm (0.48 in)…and women overreported their height by 0.68 cm (0.27 in).” The second study, performed in Norway on people with and without osteoarthritis, “showed a strong dose-dependent association between a higher measured BMI and greater overreporting of height…” The study speculated that the overreporting of height in the elderly was likely due to the fact that the elderly tend to forget that they shrink as they age.

Fair enough. Let’s say our patient overreported their height by the greater average amount of 1.22 cm. That would mean the patient’s actual (or measured, had the care providers stood the patient up and obtained a measurement) height could have actually been 168.88 cm (instead of the reported 170.1 cm). That would give our patient a BMI of 43.2 (168.88 cm height, 123.1 kg weight); an even higher BMI than the 42.5 that was recorded in the medical record. So, underreporting of height actually skews the BMI higher to support a diagnosis of obesity. How could anyone with high school level math skills deny a legally assigned diagnosis code based on a tendency of the elderly to overreport their height by less than a half of an inch?

It’s hard to fathom how this could be happening, but it is. The provider will be taking this case next to arbitration. Here’s to hoping the arbitrator has some common sense and a basic understanding of simple math.