E89.1 Code First Points to E13. Complication Character Picks HCC 36, 37, or 38.

E89.1 is postprocedural hypoinsulinemia. It is billable. It has verified no payable CMS-HCC V28 mapping. The live card Code First note says: if applicable, diabetes mellitus (postpancreatectomy) (postprocedural) (E13.-). The V28 diabetes HCC, when present, comes from the billable E13 child.

The E13 header Includes postpancreatectomy diabetes mellitus and postprocedural diabetes mellitus. E13 is not billable. Pick the child that matches the complication story, then confirm the CSV / card map.

*Current as of September 11, 2026. V28 mapping and CNA factors come from the live code pages named below and `ICD10_CC_mappings_CMS_HCC_2026_v28.csv`. Payment year 2026 is 100% V28. Coefficients are source-labeled references, not member totals. Look the exact codes up. Do not code from this recap. Do not invent a V24 map.*

Quick answer

E89.1 does not map in CMS-HCC V28. Code First points to E13.- when postpancreatectomy or postprocedural diabetes applies. Complication character on the E13 child picks HCC 36, 37, or 38. Watch the hypoglycemia trap: E13.641 (with coma) is 36; E13.649 (without coma) is 38.

Desk table: sample E13 maps

Sequencing: E89.1 and E13

1. When the note supports postprocedural / postpancreatectomy hypoinsulinemia, report E89.1.

2. Follow Code First on E89.1: if applicable, also report the supported E13.- diabetes code.

3. Follow Use Additional on E89.1 when supported: Z90.41- (acquired absence of pancreas) and Z79.4 (insulin use).

4. Do not treat E89.1 as the V28 payment HCC. Look the E13 child up.

Live E13 child cards in this desk set show no Code First line in display. The postpancreatectomy Code First instruction sits on E89.1, pointing to E13.-.

Hypoglycemia: coma vs no coma, plus E16.A-

Parent E13.64 lists Use Additional: code for hypoglycemia level, if applicable (E16.A-).

• E13.641 (with coma) maps to HCC 36
• E13.649 (without coma) maps to HCC 38

E16.A1, E16.A2, and E16.A3 have no payable V28 mapping on the live cards. Add the level when the note supports it. Do not invent an HCC for E16.A-.

Complication character picks the diabetes HCC

Under V28, E13 children follow the same three diabetes tiers as the other diabetes families:

• HCC 36 Severe acute (example: E13.10; E13.641)
• HCC 37 Chronic complications (example: E13.22; E13.40)
• HCC 38 No / glycemic / unspecified complications (example: E13.9; E13.65; E13.649)

See also the type-2 glycemic desk E11.65 Maps to HCC 38 in V28, Not HCC 37 and E11.22. Those are E11 lanes. This post owns E13 / E89.1.

MEAT

Mapped E13 children still need monitoring, evaluation, assessment, or treatment this calendar year. A problem-list post-whipple diabetes row from last year does not carry the HCC forward. See MEAT and problem lists.

Common misses

1. Coding E89.1 alone and expecting a V28 diabetes HCC. No file row.

2. Looking for Code First on the E13 child display and missing the note on E89.1.

3. Assigning E13.649 to HCC 36 because hypoglycemia sounds acute. CSV + card: 38.

4. Inventing an HCC for E16.A- hypoglycemia level.

5. Using the E13 header on a claim. Not billable.

6. Stacking E10 and E11 when documentation is other-specified / postpancreatectomy. E13 Includes postpancreatectomy DM; Excludes1 blocks E10.- on the E13 card.

7. Inventing a V24 map instead of selecting the historical period on the card.

8. Copying E13.22 without Use Additional N18 stage when the card lists it and the note supports a stage.

Two-minute check

1. Is this other-specified / postpancreatectomy / postprocedural diabetes, not E10 or E11?

2. If postprocedural hypoinsulinemia is supported, is E89.1 on the claim with Code First E13.- when applicable?

3. Which billable E13 child matches the complication (acute / chronic / none-glycemic)?

4. Confirm CSV / live card maps to 36, 37, or 38.

5. Hypoglycemia: with coma (E13.641 maps to 36) vs without (E13.649 maps to 38)? Add E16.A- level when supported.

6. MEAT this year. Do not invent maps for E89.1 or E16.A-.

Related

• E89.1 card
• E13 header
• E13.10 card
• E13.641 card
• E13.649 card
• E13.22 card
• E13.65 card
• V28 HCC 36
• V28 HCC 37
• V28 HCC 38
• E11.65 glycemic desk
• MEAT
• Encoder

Disclaimer

By the HCC Buddy Coding Team. V28 mappings from the cited live code pages and `ICD10_CC_mappings_CMS_HCC_2026_v28.csv`, current as of September 11, 2026. Coefficients are source-labeled references, not member totals. Not medical advice. Do not code from this recap. Not a Coding Clinic reprint. Not a rewrite of I10-I13, E66.2, E11.9, E11.65, E11.22, L12.0, or D59.31.