Convert ICD-10 Code I10 to ICD-9

Source ICD-10 Code		Target ICD-9 Code
I10 Essential (primary) hypertension		401.0 Malignant hypertension
Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.
I10 Essential (primary) hypertension		401.1 Benign hypertension
Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.
I10 Essential (primary) hypertension		401.9 Hypertension NOS
Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.

ICD-10 to ICD-9 crosswalk for code I10 - essential (primary) hypertension based on the most recent General Equivalence Mappings (GEMS) information.