HCC 200: Friedreich and Other Hereditary Ataxias; Huntington Disease ICD-10-CM
CMS-HCC Category 200 (Friedreich and Other Hereditary Ataxias; Huntington Disease) is a payment HCC in the V28 Medicare Advantage risk adjustment model. For payment year 2026 it adds a risk adjustment factor between 0.000 and 0.428 to a beneficiary's RAF score depending on the payment segment (0.279 for a community, non-dual, aged enrollee). 17 ICD-10-CM diagnosis codes map to HCC 200. 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 | 0.279 |
| Community, partial-benefit dual, aged | 0.050 |
| Community, full-benefit dual, aged | 0.165 |
| Community, non-dual, disabled | 0.208 |
| Community, partial-benefit dual, disabled | 0.428 |
| Community, full-benefit dual, disabled | 0.281 |
| Institutional | 0.000 |
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 HCC 200 neither supersedes nor is superseded by any other category, so it always counts alongside unrelated HCCs.
ICD-10-CM Codes That Map to HCC 200 17 codes
- G10 Huntington's disease from V24 HCC 78
- G11.0 Congenital nonprogressive ataxia from V24 HCC 72
- G11.10 Early-onset cerebellar ataxia, unspecified from V24 HCC 72
- G11.11 Friedreich ataxia from V24 HCC 72
- G11.19 Other early-onset cerebellar ataxia from V24 HCC 72
- G11.2 Late-onset cerebellar ataxia from V24 HCC 72
- G11.3 Cerebellar ataxia with defective DNA repair from V24 HCC 72
- G11.4 Hereditary spastic paraplegia from V24 HCC 72
- G11.5 Hypomyelination - hypogonadotropic hypogonadism - hypodontia from V24 HCC 72
- G11.6 Leukodystrophy with vanishing white matter disease from V24 HCC 72
- G11.8 Other hereditary ataxias from V24 HCC 72
- G11.9 Hereditary ataxia, unspecified from V24 HCC 72
- G31.80 Leukodystrophy, unspecified from V24 HCC 52
- G90.B LMNB1-related autosomal dominant leukodystrophy from V24 HCC 52
- G93.42 Megalencephalic leukoencephalopathy with subcortical cysts from V24 HCC 52
- G93.43 Leukoencephalopathy with calcifications and cysts from V24 HCC 52
- G93.44 Adult-onset leukodystrophy with axonal spheroids from V24 HCC 52
Every code above carries the full HCC 200 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 200
What is HCC 200 in the CMS-HCC model?
HCC 200 is CMS-HCC Category 200 (Friedreich and Other Hereditary Ataxias; Huntington Disease) in the V28 risk adjustment model. It covers 17 ICD-10-CM diagnosis codes that raise a Medicare Advantage beneficiary's risk score when documented.
What is the RAF weight for HCC 200?
For payment year 2026, HCC 200 adds 0.279 to the RAF score of a community, non-dual, aged beneficiary. The published weights range from 0.000 to 0.428 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.
