HCC 198: Multiple Sclerosis ICD-10-CM
CMS-HCC Category 198 (Multiple Sclerosis) is a payment HCC in the V28 Medicare Advantage risk adjustment model. For payment year 2026 it adds a risk adjustment factor between 0.226 and 1.143 to a beneficiary's RAF score depending on the payment segment (0.647 for a community, non-dual, aged enrollee). 20 ICD-10-CM diagnosis codes map to HCC 198. It sits at the top of its hierarchy: no other condition category supersedes it.
RAF Weight by Payment Segment 7 segments
| Payment Segment | Relative Factor |
|---|---|
| Community, non-dual, aged | 0.647 |
| Community, partial-benefit dual, aged | 0.569 |
| Community, full-benefit dual, aged | 0.791 |
| Community, non-dual, disabled | 0.908 |
| Community, partial-benefit dual, disabled | 0.770 |
| Community, full-benefit dual, disabled | 1.143 |
| Institutional | 0.226 |
A beneficiary is scored in exactly one segment, set by Medicaid (dual) status, aged or disabled entitlement, and residence. Factors are relative weights, not dollar amounts; new-enrollee segments score on demographics only. HCC 198 neither supersedes nor is superseded by any other category, so it always counts alongside unrelated HCCs.
ICD-10-CM Codes That Map to HCC 198 20 codes
- G35 Multiple sclerosis Non-billable from V24 HCC 77
- G35.A Relapsing-remitting multiple sclerosis new to V28
- G35.B0 Primary progressive multiple sclerosis, unspecified new to V28
- G35.B1 Active primary progressive multiple sclerosis new to V28
- G35.B2 Non-active primary progressive multiple sclerosis new to V28
- G35.C0 Secondary progressive multiple sclerosis, unspecified new to V28
- G35.C1 Active secondary progressive multiple sclerosis new to V28
- G35.C2 Non-active secondary progressive multiple sclerosis new to V28
- G35.D Multiple sclerosis, unspecified new to V28
- G36.0 Neuromyelitis optica [Devic] from V24 HCC 77
- G36.1 Acute and subacute hemorrhagic leukoencephalitis [Hurst] from V24 HCC 77
- G36.8 Other specified acute disseminated demyelination from V24 HCC 77
- G36.9 Acute disseminated demyelination, unspecified from V24 HCC 77
- G37.0 Diffuse sclerosis of central nervous system from V24 HCC 77
- G37.1 Central demyelination of corpus callosum from V24 HCC 77
- G37.2 Central pontine myelinolysis from V24 HCC 77
- G37.5 Concentric sclerosis [Balo] of central nervous system from V24 HCC 77
- G37.81 Myelin oligodendrocyte glycoprotein antibody disease from V24 HCC 77
- G37.89 Other specified demyelinating diseases of central nervous system from V24 HCC 77
- G37.9 Demyelinating disease of central nervous system, unspecified from V24 HCC 77
Every code above carries the full HCC 198 weight when documented and reported on a Medicare Advantage encounter. The code link opens its full page with the complete risk adjustment card.
Questions About HCC 198
What is HCC 198 in the CMS-HCC model?
HCC 198 is CMS-HCC Category 198 (Multiple Sclerosis) in the V28 risk adjustment model. It covers 20 ICD-10-CM diagnosis codes that raise a Medicare Advantage beneficiary's risk score when documented.
What is the RAF weight for HCC 198?
For payment year 2026, HCC 198 adds 0.647 to the RAF score of a community, non-dual, aged beneficiary. The published weights range from 0.226 to 1.143 across the seven payment segments shown above.
Related References
Source: Centers for Medicare & Medicaid Services, Payment Year 2026 risk adjustment mapping and model software releases (CMS-HCC V28), applied to the FY 2026 ICD-10-CM code set. ICD List is not affiliated with CMS.
