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 HCC 200 neither supersedes nor is superseded by any other category, so it always counts alongside unrelated HCCs.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 (living at home, age 65 or over, not also enrolled in Medicaid). 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.
