E66.2
Morbid (severe) obesity with alveolar hypoventilation
E66.2 (also written E662) is a billable ICD-10-CM diagnosis code for morbid (severe) obesity with alveolar hypoventilation. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 10 codes in category E66 (Overweight and obesity). The Alphabetic Index lists it under 11 entries. Its coding notes include a Code first instruction, a Use additional code instruction, 1 Excludes1 entry and 4 Excludes2 entries.
Code first
If the underlying condition listed here is present and known, sequence it first.
Use additional code
Add the listed code as a secondary code, if known.
Excludes1
Not coded here. The listed conditions generally should not be reported together.
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
Care settings
How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.
Home Health Primary
Accepted as the primary (principal) diagnosis on a home health claim. The Home Health Grouper assigns it to the MMTA - Other clinical group.
Source: CMS Home Health Grouper Software v07.2.26, effective October 1, 2026Hospital CC
Counts as a complication or comorbidity (CC) when reported as a secondary diagnosis on an inpatient claim. It does not count when the principal diagnosis is one of the 13 codes in its exclusion list. Some MS-DRGs also ignore a CC or MCC that defines the DRG.
Source: CMS MS-DRG Definitions Manual v44, effective October 1, 2026, Appendix CInclusion terms
Conditions classified to this code.
- Obesity hypoventilation syndrome (OHS)
- Pickwickian syndrome
Notes
Also from chapter/block level (1 note)
- All neoplasms, whether functionally active or not, are classified in Chapter 2. Appropriate codes in this chapter (i.e. E05.8, E07.0, E16-E31, E34.-) may be used as additional codes to indicate either functional activity by neoplasms and ectopic endocrine tissue or hyperfunction and hypofunction of endocrine glands associated with neoplasms and other conditions classified elsewhere.
Alphabetic Index terms
Terms the official Alphabetic Index lists for this code. 11 entries
- Obesity, hypoventilation syndrome (OHS)
- Obesity, morbid, with, alveolar hypoventilation
- Obesity, morbid, with, obesity hypoventilation syndrome (OHS)
- Obesity, with alveolar hypoventilation
- OHS (obesity hypoventilation syndrome)
- Pickwickian syndrome
- Syndrome, alveolar hypoventilation
- Syndrome, cardiopulmonary-obesity
- Syndrome, hypoventilation, obesity (OHS)
- Syndrome, obesity hypoventilation (OHS)
- Syndrome, Pickwickian