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Basic information on Obesity ICD-10 CM codes

Obesity means having too much body fat. It is different from being overweight, which means weighing too much.Body mass index (BMI) is a calculation that takes a person’s weight and height into account to measure body size. E66* category codes are used as ICD-10 code for diagnosis reimbursement of Overweight and Obesity. Its corresponding ICD-9 code is 278.

Description of obesity ICD-10 CM Code for Coders

E66 Overweight and obesity
Code first obesity complicating pregnancy, childbirth and the puerperium, if applicable (O99.21-)
Use additional code to identify body mass index (BMI), if known (Z68.-)
Excludes1: adiposogenital dystrophy (E23.6)
lipomatosis NOS (E88.2)
lipomatosis dolorosa [Dercum] (E88.2)
Prader-Willi syndrome (Q87.11)

E66.0 Obesity due to excess calories

E66.01 Morbid (severe) obesity due to excess calories 22
Excludes1: morbid (severe) obesity with alveolar hypoventilation (E66.2)

E66.09 Other obesity due to excess calories

E66.1 Drug-induced obesity
Use additional code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5)

E66.2 Morbid (severe) obesity with alveolar hypoventilation 22
Obesity hypoventilation syndrome (OHS)
Pickwickian syndrome

E66.3 Overweight

E66.8 Other obesity

E66.9 Obesity, unspecified
Obesity NOS

Several codes are used to identify overweight and obesity, including the following:
E66.01 Morbid (severe) obesity due to excess calories
E66.09 Other obesity due to excess calories
E66.1 Drug-induced obesity
E66.2 Morbid (severe) obesity with alveolar hypoventilation
E66.3 Overweight
E66.8 Other obesity
E66.9 Obesity, unspecified

These codes are assigned only on the basis of the physician’s diagnostic statement. Category E66,
Overweight and obesity, requires the assignment of an additional code (Z68.-) for the body mass index
(BMI), if known. BMI is a measure of weight for height used as a tool for indicating weight status in
adults. Coding BMI is an exception to the guideline that requires that code assignment be based on the
documentation by the provider.

The BMI code assignment should be based on medical record documentation, which may be found in the notes of other clinicians involved in the care of the patient (i.e., physician or other qualified health care practitioner legally accountable for establishing the patient’s diagnosis). BMI is typically documented by the dietitian or the nurse. Although BMI may be reported on the basis of another clinician’s documentation, the codes for the associated diagnosis (such as overweight and obesity) must be based on the provider’s documentation.

Being overweight may place a patient at increased risk for certain medical conditions. However, overweight may only be reported when it meets the definition of a reportable diagnosis per Section III, Reporting Additional Diagnoses, of the ICD-10-CM Official Guidelines for Coding and Reporting. Neither the code for overweight nor the BMI code is assigned when there is no documentation that the diagnosis “overweight” meets the definition of a reportable secondary diagnosis. Obesity and morbid obesity are always clinically significant and should be coded and reported when documented by the provider. The BMI code may be reported with these conditions when BMI is documented. BMI codes should not be assigned during pregnancy.

Occasionally, a patient’s BMI may fluctuate during a hospital stay. If the BMI fluctuation is linked to a clinically significant condition, such as malnutrition or anorexia nervosa, code the most severe BMI value recorded during the admission. However, the BMI codes are not intended to report changes in BMI caused by fluid overload/retention. BMI fluctuation caused by weight gain due to excess fluid is not the same as that caused by loss or gain of body mass; weight from excess fluid can lead to an overestimate of the BMI, making it an inaccurate indicator of the patient’s actual weight status.

Code E66.2, Morbid (severe) obesity with alveolar hypoventilation, also known as Pickwickian syndrome, involves sleep-disordered breathing that causes a person to stop breathing for short periods of time while sleeping. It may be related to both obesity and neurological conditions

Related obesity ICD-10 CM Code Synonyms

Overweight in childhood
Overweight pediatric
Overweight, body mass index (bmi) 25-25.9
Overweight, body mass index (bmi) 26-26.9
Overweight, body mass index (bmi) 27-27.9
Overweight, body mass index (bmi) 29-29.9
Adult obesity with bmi between 30 to 30.9
Adult obesity with bmi between 31 to 31.9
Adult obesity with bmi between 32 to 32.9
Adult obesity with bmi between 33 to 33.9
Adult obesity with bmi between 34 to 34.9
Adult obesity with bmi between 35 to 35.9

Adult obesity with bmi between 36 to 36.9
Adult obesity with bmi between 37 to 37.9
Adult obesity with bmi between 38 to 38.9
Adult obesity with bmi between 39 to 39.9
Childhood obesity
Childhood obesity, bmi 95-100 percentile
Maternal obesity complicating pregnancy, childbirth and the puerperium, antepartum
Maternal obesity during childbirth
Maternal obesity in pregnancy
Obesity (body mass index 96-100 percentile for age)
Obesity body mass index (bmi) 95-99 percentile for age
Obesity complicating period after childbirth
Obesity counseling

Obesity counseling done
Obesity in childbirth
Obesity in pregnancy
Obesity of adult, bmi 30-34.9
Obesity of adult, bmi 35-39.9
Obesity, bmi 30-34.9, adult
Obesity, bmi 35-39.9, adult
Obesity, body mass index (bmi) 30-30.9

Obesity, body mass index (bmi) 31-31.9
Obesity, body mass index (bmi) 32-32.9
Obesity, body mass index (bmi) 33-33.9
Obesity, body mass index (bmi) 34-34.9
Obesity, body mass index (bmi) 35-35.9
Obesity, body mass index (bmi) 36-36.9
Obesity, body mass index (bmi) 37-37.9
Obesity, body mass index (bmi) 38-38.9
Obesity, body mass index (bmi) 39-39.9
Postpartum obesity
Body mass index 25-29 – overweight
Childhood overweight, bmi greater than 85 percentile

Overweight (body mass index 85-95 percentile for age)
Overweight adult with bmi 25-25.9
Overweight adult with bmi 26-26.9
Overweight adult with bmi 27-27.9
Overweight adult with bmi 29-29.9
Overweight body mass index (bmi) 25-29.9