I12.9

HCC Category Mapping

What This Code Means

High blood pressure that has caused kidney disease in stages 1 through 4, where the kidneys are damaged but still functioning at some level.

Coding Tips

• •Use I12.9 for stages 1-4 CKD or when the CKD stage is not specified; do not use for stage 5 (use I12.0 instead)
• •Ensure documentation establishes the causal relationship between hypertension and the chronic kidney disease

Clinical Significance

Hypertensive chronic kidney disease with stages 1-4 or unspecified CKD captures the common comorbidity of hypertension and earlier-stage chronic kidney disease. ICD-10-CM guidelines assume a causal relationship between hypertension and CKD when they coexist. While this code itself maps only to the RxHCC model, the additional CKD stage code may contribute independently to risk adjustment.

Documentation Requirements

• ✓Documented diagnosis of hypertension
• ✓Documented chronic kidney disease (stages 1-4 or unspecified)
• ✓An additional code from N18.1-N18.4 or N18.9 to identify the CKD stage
• ✓Current estimated glomerular filtration rate (eGFR)
• ✓Current treatment regimen for both conditions
• ✓Documentation of CKD stage based on eGFR values
• ✓Note: If CKD stage is not specified, use N18.9 as the additional code

Commonly Confused Codes