What is ICD-10 code J43.9?

J43.9 is the ICD-10-CM diagnosis code for Emphysema, unspecified. A lung disease where air sacs in the lungs are damaged, causing difficulty breathing and reduced oxygen exchange, but the specific type is not documented. It belongs to the ICD-10-CM chapter for diseases of the respiratory system (j00-j99). J43.9 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. J43.9 is part of the FY2026 ICD-10-CM code set published by the CMS National Center for Health Statistics and used on Medicare, Medicaid, and commercial claims in the United States.

Yes. J43.9 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. J43.9 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

What is the V28 vs V24 difference for J43.9?

CMS phased in the V28 risk adjustment model over payment years 2024 (33%), 2025 (67%), and 2026 (100%), replacing V24. V28 consolidates HCC categories, removes some lower-acuity conditions, and recalibrates RAF weights across the entire model. For J43.9, V28 maps to Chronic Obstructive Pulmonary Disease, Interstitial Lung Disorders, and Other Chronic Lung Disorders at RAF 0.319 while V24 mapped to Chronic Obstructive Pulmonary Disease at RAF 0.335. Both models can still appear in legacy data and in payer-specific lookback periods.

What should coders know when reporting J43.9?

Use this code only when emphysema is diagnosed but the specific type (centriacinar, panacinar, or paraseptal) cannot be determined from documentation Review medical records for any mention of smoking history or alpha-1 antitrypsin deficiency, which may help specify the type Because J43.9 maps to a payment HCC, the documentation must also satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's risk adjustment score.

J43.9: Emphysema, unspecified — ICD-10 | Chronic Obstructive Pulmonary Disease, Interstitial Lung

ICD-10-CM Code View

HCC Buddy Code Card

Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.

Code lookupJ43.9Effective periodFY2026 Apr Update (Apr 1-Sep 30)

FY 2026 Apr update / Diseases of the respiratory system (J00-J99) / Chronic lower respiratory diseases (J40-J4A)

J43.9

Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidance

Emphysema, unspecified

A lung disease where air sacs in the lungs are damaged, causing difficulty breathing and reduced oxygen exchange, but the specific type is not documented.

Buddy Insight

Unspecified emphysema is used when the provider documents emphysema without specifying the anatomical type (centrilobular, panlobular, paraseptal, etc.

CMS-HCC V28

Mapped

HCC 280

Chronic Obstructive Pulmonary...

RAF 0.319

CMS-HCC V24

Mapped

HCC 111

Chronic Obstructive Pulmonary...

RAF 0.335

ACA/HHS

Not risk-adjusted for this model/period.

RAF 0

ESRD/PACE

Not risk-adjusted for this model/period.

RAF 0

RXHCC

Mapped

HCC 229

COPD and Chronic Bronchitis

RAF 0.0

Code Trumping

Basket needed

Compare selected patient codes to show trumped or trumps impact.

Code Book Path

Official

J43Emphysema

J43.9Emphysema, unspecified

Inclusion Terms

Official

Bullous emphysema (lung)(pulmonary)
Emphysema (lung)(pulmonary) NOS
Emphysematous bleb
Vesicular emphysema (lung)(pulmonary)

Excludes 2

Official

emphysema due to inhalation of chemicals, gases, fumes or vapors (J68.4)
emphysema with chronic (obstructive) bronchitis (J44.-)
emphysematous (obstructive) bronchitis (J44.-)
traumatic subcutaneous emphysema (T79.7)

Related Child Codes

Official

J43.0Unilateral pulmonary emphysema [MacLeod's syndrome]

J43.1Panlobular emphysema

J43.2Centrilobular emphysema

J43.8Other emphysema

Includes

Official

ICD-10-CM does not list Includes notes for J43.9 in this effective period.

Excludes 1

Official

compensatory emphysema (J98.3)
interstitial emphysema (J98.2)
mediastinal emphysema (J98.2)
neonatal interstitial emphysema (P25.0)
surgical (subcutaneous) emphysema (T81.82)

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for J43.9 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for J43.9 in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for J43.9 in this effective period.

Buddy Documentation Tip

HCC Buddy guidance

Provider documentation explicitly stating a diagnosis of emphysema

Pulmonary function testing showing obstructive pattern, particularly reduced FEV1/FVC ratio and diffusion capacity

Clinical symptoms: progressive dyspnea, barrel chest, prolonged expiration

Chest imaging (CT preferred) documenting emphysematous changes

MEAT Support

HCC Buddy guidance

Provider documentation explicitly stating a diagnosis of emphysema

Pulmonary function testing showing obstructive pattern, particularly reduced FEV1/FVC ratio and diffusion capacity

Clinical symptoms: progressive dyspnea, barrel chest, prolonged expiration

Chest imaging (CT preferred) documenting emphysematous changes

Audit Caution

HCC Buddy guidance

Defaulting to J43.9 when CT imaging describes a specific pattern — always code to highest specificity

Using emphysema codes based on incidental CT findings without provider clinical assessment

Not recognizing that J43.9 and J44.9 may be redundant — query provider about the preferred characterization

Failing to add tobacco use/dependence codes when emphysema is present in a smoker

Common Mistakes

HCC Buddy guidance

J43.2 — Centrilobular emphysema: preferred when CT shows upper-lobe predominant centrilobular pattern

J43.1 — Panlobular emphysema: preferred when CT shows lower-lobe predominant panacinar pattern

J44.9 — COPD, unspecified: overlapping concept; COPD encompasses emphysema and chronic bronchitis

J43.8 — Other emphysema: use for paraseptal, bullous, or other specified patterns

Last updated: FY2026 ICD-10-CM Apr update, Apr 1, 2026 through Sep 30, 2026. CMS-HCC V28 is 100% phased in for payment year 2026.

Is J43.9 an HCC code?

Yes. J43.9 maps to Chronic Obstructive Pulmonary Disease, Interstitial Lung Disorders, and Other Chronic Lung Disorders under the CMS-HCC V28 risk adjustment model (and Chronic Obstructive Pulmonary Disease under V24).

HCC Category Mapping

V28HCC 280, Chronic Obstructive Pulmonary Disease, Interstitial Lung Disorders, and Other Chronic Lung Disorders

0.319

V24HCC 111, Chronic Obstructive Pulmonary Disease

0.335

RxHCCHCC 229, COPD and Chronic Bronchitis

0.000

RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.

Work J43.9 in the Code Book — tabular path, V28 RAF, and MEAT checklist →

MEAT Criteria for J43.9

For J43.9to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically, it has to be re-documented and supported each calendar year.

MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
EEvaluate: test results, medication response, or physical findings reviewed by the provider
AAssess: explicit mention in the assessment or plan with acknowledgment of status
TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis

Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed J43.9 during that encounter, not just copy-forwarded from a problem list.

Coder workflow notes

Get the V28 RAF + MEAT cheat sheet

One printable page: confirm a code's V28 HCC status, its RAF weight, and the MEAT your note needs to make it stick. Free, no card.

Free PDF. No card. Unsubscribe anytime.

What This Code Means

J43.9 is the ICD-10-CM diagnosis code for emphysema, unspecified. A lung disease where air sacs in the lungs are damaged, causing difficulty breathing and reduced oxygen exchange, but the specific type is not documented. J43.9 sits in the ICD-10-CM chapter for diseases of the respiratory system (j00-j99), within the section covering chronic lower respiratory diseases (j40-j4a).

Under the CMS-HCC V28 risk adjustment model, J43.9 maps to Chronic Obstructive Pulmonary Disease, Interstitial Lung Disorders, and Other Chronic Lung Disorders (HCC 280) with a community, non-dual, aged base RAF weight of 0.319. Under the older CMS-HCC V24 model, J43.9 maps to Chronic Obstructive Pulmonary Disease (HCC 111) with a community, non-dual, aged base RAF weight of 0.335. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.

Use this code only when emphysema is diagnosed but the specific type (centriacinar, panacinar, or paraseptal) cannot be determined from documentation. Because J43.9 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for J43.9 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•Use this code only when emphysema is diagnosed but the specific type (centriacinar, panacinar, or paraseptal) cannot be determined from documentation
•Review medical records for any mention of smoking history or alpha-1 antitrypsin deficiency, which may help specify the type

Clinical Significance

Unspecified emphysema is used when the provider documents emphysema without specifying the anatomical type (centrilobular, panlobular, paraseptal, etc.). While it carries the same HCC mapping as specified types, medical record quality and clinical accuracy are better served by identifying the specific pattern when imaging is available.

Documentation Requirements

✓Provider documentation explicitly stating a diagnosis of emphysema
✓Pulmonary function testing showing obstructive pattern, particularly reduced FEV1/FVC ratio and diffusion capacity
✓Clinical symptoms: progressive dyspnea, barrel chest, prolonged expiration
✓Chest imaging (CT preferred) documenting emphysematous changes
✓Treatment plan including bronchodilators, oxygen therapy, pulmonary rehabilitation as indicated
✓Smoking history and cessation status

Commonly Confused Codes

•J43.2: Centrilobular emphysema: preferred when CT shows upper-lobe predominant centrilobular pattern
•J43.1: Panlobular emphysema: preferred when CT shows lower-lobe predominant panacinar pattern
•J44.9: COPD, unspecified: overlapping concept; COPD encompasses emphysema and chronic bronchitis
•J43.8: Other emphysema: use for paraseptal, bullous, or other specified patterns