When should I use J45.40?

Pulmonology follow-up for established moderate persistent asthma, currently well-controlled on fluticasone/salmeterol. Primary care visit for asthma action plan review, patient using daily controller inhaler, symptoms controlled. Asthma clinic encounter documenting severity classification after spirometry testing. Annual asthma assessment visit, patient reports daily mild symptoms well-controlled with ICS/LABA, no recent exacerbations. Medication management visit for moderate persistent asthma, refilling Advair prescription. Pre-operative evaluation documenting moderate persistent asthma as comorbidity, currently stable

Diseases of the Respiratory System

ICD-10 Code: J45.40

Moderate Persistent Asthma, Uncomplicated

Moderate persistent asthma, uncomplicated represents chronic inflammatory airway disease classified as moderate severity based on symptom frequency (daily symptoms, nighttime awakenings >1x/week) and lung function (FEV1 60-80% predicted), currently stable without acute exacerbation or status asthmaticus.

Clinical Information

Moderate persistent asthma is classified according to the NIH Expert Panel Report 3 (EPR-3) guidelines based on impairment (symptom frequency, nighttime awakenings, SABA use, lung function) and risk (exacerbation history). Moderate persistent asthma is defined by: (1) daily symptoms, (2) nighttime awakenings >1x/week but not nightly, (3) daily use of short-acting beta-agonist (SABA), (4) some limitation of normal activity, and (5) FEV1 60-80% of predicted or FEV1/FVC reduced 5% below normal. This classification requires medium-dose inhaled corticosteroid (ICS) with long-acting beta-agonist (LABA) for maintenance therapy, such as fluticasone/salmeterol (Advair) or budesonide/formoterol (Symbicort). Patients should also have SABA rescue inhaler for breakthrough symptoms. The 'uncomplicated' designation (fifth character '0') indicates stable disease without current exacerbation. Patients with moderate persistent asthma typically have good asthma control when adherent to controller medications but experience significant symptoms when medications are missed or discontinued. They are at moderate risk for exacerbations requiring systemic corticosteroids. Regular follow-up every 1-6 months is recommended to assess control, adjust medications, and review asthma action plan.

Coding Guidelines

1Use J45.40 when provider specifically documents 'moderate persistent asthma' AND patient is currently stable (no exacerbation)
2For acute exacerbation, change fifth character from '0' to '1': J45.41 (moderate persistent asthma with acute exacerbation)
3For status asthmaticus, use J45.42 instead
4Requires documented asthma severity classification; if severity not specified, use J45.909 (unspecified asthma)
5Severity classification should be based on EPR-3 or GINA guidelines: symptom frequency, nighttime symptoms, SABA use, and spirometry
6May use additional codes for allergic triggers: J30.9 (allergic rhinitis), tobacco exposure (Z77.22)

Common Uses

Pulmonology follow-up for established moderate persistent asthma, currently well-controlled on fluticasone/salmeterol
Primary care visit for asthma action plan review, patient using daily controller inhaler, symptoms controlled
Asthma clinic encounter documenting severity classification after spirometry testing
Annual asthma assessment visit, patient reports daily mild symptoms well-controlled with ICS/LABA, no recent exacerbations
Medication management visit for moderate persistent asthma, refilling Advair prescription
Pre-operative evaluation documenting moderate persistent asthma as comorbidity, currently stable

Related ICD-10 Codes

J45.41Moderate persistent asthma with acute exacerbation

J45.42Moderate persistent asthma with status asthmaticus

J45.30Mild persistent asthma, uncomplicated (less severe classification)

J45.50Severe persistent asthma, uncomplicated (more severe classification)

J45.909Unspecified asthma, uncomplicated (use if severity not documented)

J30.9Allergic rhinitis, unspecified (often coexists)

Documentation Requirements

Provider must document asthma severity: 'moderate persistent asthma' based on EPR-3 or GINA classification
Include criteria supporting moderate classification: daily symptoms, nighttime awakenings >1x/week, FEV1 60-80%
Document current control status: 'well-controlled,' 'stable,' 'at goal,' or 'uncomplicated' (to justify '0' fifth character)
Include spirometry results: FEV1, FEV1/FVC ratio, percent predicted, reversibility testing
List current controller medications: ICS/LABA combination (specific drug, dose, frequency), SABA rescue use frequency
Document absence of acute exacerbation or status asthmaticus; if present, use different code

Real-World Coding Examples

38-year-old returns for asthma follow-up. Diagnosed with moderate persistent asthma based on spirometry (FEV1 65% predicted) and symptom burden (daily symptoms, wakes 2x/week with cough). Currently stable on Advair 250/50 twice daily, albuterol rescue 3-4x/week. No exacerbations in past year. Diagnosis: Moderate persistent asthma, uncomplicated (J45.40).

Allergy/immunology visit. Patient with documented moderate persistent asthma, well-controlled on budesonide/formoterol. Recent peak flow monitoring shows personal best at 75% predicted. Assessment: Moderate persistent asthma, stable (J45.40). Continue current therapy.

Annual physical exam. History of 'moderate persistent asthma' per pulmonologist. Patient compliant with Symbicort, reports occasional SABA use with exercise. No recent ER visits or steroid bursts. Exam: lungs clear bilaterally. Diagnosis: J45.40.

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Medical coding for Diseases of the Respiratory System