2027 ICD-10-CM Diagnosis Code I15.8Other secondary hypertension
ICD-10-CM Codes›I00–I99›I10-I1A›I15
- Billable — Valid for Submission
- Chronic Condition
I15.8 is a billable ICD-10-CM diagnosis code for other secondary hypertension. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 304 through 305. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Hypertension with complications and secondary hypertension.
I15.8 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model. It still risk-adjusts in the RxHCC Part D (V08) category 187 for payment year 2027.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
I15.8 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model, but it maps to payment categories in the other CMS models shown below.
Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Benign hypertension
- Benign secondary hypertension
- Exertional hypertension
- Hypertension associated with transplantation
- Hypertension due to aortic arch obstruction
- Hypertension due to gain-of-function mutation in mineralocorticoid receptor
- Hypertension induced by oral contraceptive pill
- Hypertension secondary to drug
- Hypertension secondary to kidney transplant
- Hypertension secondary to renal disease in obstetric context
- Intermittent hypertension
- Labile hypertension due to being in a clinical environment
- Multiple drug intolerant hypertension
- Perioperative hypertension
- Postoperative hypertension
- Secondary hypertension due to congenital heart disorder
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to I15.8: its own notes plus those printed at I15, block I10-I1A, and Chapter 9. A note printed at a category, block or chapter applies to every code under it.
Excludes1
Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
- systemic connective tissue disorders (M30-M36)
- transient cerebral ischemic attacks and related syndromes (G45.-)
Use Additional Code
Add a second code, after this one, to fully describe the condition.
Code Also
A second code may be needed to fully describe the condition; the note gives no sequencing direction.
- underlying condition
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name I15.8, its category, or a range that includes it.
Applicable To 1
These notes mention I15.8.
Excludes1 1
These codes carry an Excludes1 note naming I15.8: they are not reported together with it, unless the two conditions are unrelated.
Code First 1
These codes say to code first a condition named in the note, and I15.8 is one of the conditions named.
Use Additional Code 3
These codes say to use an additional code from the note, and I15.8 is one of the codes named.
- O10.4 Pre-existing secondary hypertension complicating pregnancy, childbirth and the puerperiumcode from I15 to identify the type of secondary hypertension names I15, which includes this code
- G31.84 Mild cognitive impairment of uncertain or unknown etiology
- Block I60-I69 Cerebrovascular diseases
Code Also 6
These codes say I15.8 may also be needed to fully describe the condition. The note gives no sequencing direction.
- E83.820 Generalized arterial calcification of infancy with unspecified genetic causalityother secondary hypertension (I15.8)
- E83.821 ENPP1 deficiency causing generalized arterial calcification of infancyother secondary hypertension (I15.8)
- E83.823 ABCC6 deficiency causing generalized arterial calcification of infancyother secondary hypertension (I15.8)
- I16 Hypertensive crisis
- Block I20-I25 Ischemic heart diseases
- Z15.3 Genetic susceptibility to kidney disease
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Secondary Hypertension
high blood pressure caused by an underlying medical condition.
Patient EducationClinical
High Blood Pressure
Blood pressure is the force of your blood pushing against the walls of your arteries. Each time your heart beats, it pumps blood into the arteries. Your blood pressure is highest when your heart beats, pumping the blood. This is called systolic pressure. When your heart is at rest, between beats, your blood pressure falls.
The full article covers:
- What is blood pressure?
- How is high blood pressure diagnosed?
- What are the different types of high blood pressure?
- Why do I need to worry about high blood pressure?
- What are the treatments for high blood pressure?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert I15.8 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About I15.8Overview
What is the ICD-10 code for other secondary hypertension?
The ICD-10-CM code for other secondary hypertension is I15.8 (sometimes written as I158). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is I15.8 (Secondary hypertension) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report other secondary hypertension on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does I15.8 group to?
When other secondary hypertension is the principal diagnosis on an inpatient stay, it groups to MS-DRG 305, 304, with relative weights from 0.7579 to 1.2010 depending on complications. Higher weights mean higher Medicare reimbursement.
Can I15.8 be reported with I97.3?
Not as a rule. The Excludes1 note at I15, which applies to I15.8, lists "postprocedural hypertension (I97.3)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).
What is the ICD-9 equivalent of I15.8?
Under the General Equivalence Mappings, other secondary hypertension converts to ICD-9-CM 405.09 (mal second hyperten NEC), 405.19 (benign second hypert NEC), and 405.99 (second hypertension NEC). The mapping is approximate, so confirm the match fits the documentation.
Does I15.8 risk-adjust for Medicare Advantage payment?
Not for Medicare Advantage: I15.8 maps to no category in the CMS-HCC V28 model. It still risk-adjusts in the RxHCC Part D (V08) category 187 (Hypertension).
