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Overlap Syndrome
At GastroDoxs in Houston, Dr. Nghia Nguyen specializes in diagnosing and treating Asthma-COPD Overlap Syndrome (ACO). Combining advanced testing—like spirometry and imaging—with tailored therapies, lifestyle guidance, compassionate care, and procedures to help you breathe easier and improve your daily life.
Dr. Nghia Nguyen, DO, is a board-certified gastroenterologist providing advanced digestive care in the Greater Houston area. He earned his medical degree from the Texas College of Osteopathic Medicine and completed both his Internal Medicine residency and Gastroenterology fellowship at the University of Texas at Rio Grande Valley. Dr. Nguyen specializes in treating conditions such as acid reflux, irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), and liver disorders.
What Is Overlap Syndrome?
Asthma-COPD Overlap Syndrome (ACO) is a chronic lung condition that combines the airway inflammation seen in asthma with the persistent airflow obstruction characteristic of COPD. Patients experience both reversible bronchospasm and fixed airway narrowing, leading to more frequent symptoms and exacerbations.
Common Causes and Risk Factors
Long-term cigarette smoking or exposure to air pollutants
History of childhood asthma or atopy (allergic rhinitis, eczema)
Genetic predisposition or family history of asthma/COPD
Past severe respiratory infections
Occupational exposure to dusts, fumes, or chemical irritants
Signs and Symptoms
Persistent cough (often productive of sputum)
Wheezing or audible chest tightness
Shortness of breath on exertion (climbing stairs, walking)
Frequent flare-ups requiring increased inhaler use
Morning chest congestion or difficulty clearing mucus
How Dr. Nghia Nguyen Diagnoses This Condition?
Dr. Nguyen uses a step-by-step approach:
Medical History & Physical Exam
He reviews your breathing symptoms, smoking or pollution exposure, past asthma/allergy history, family lung issues, and any prior lung infections.
Spirometry
A breathing test that measures airflow obstruction and helps distinguish asthma-like reversibility from fixed COPD changes.
Bronchodilator Testing
After baseline spirometry, we give a short-acting inhaler to see how much your lungs improve—a key step in identifying overlap features.
Imaging Studies
Chest X-ray to evaluate lung hyperinflation or other structural changes.
CT scan for detailed views of airway wall thickness, emphysema, or other abnormalities.
Allergy & Inflammation Testing
Skin or blood allergy panels plus eosinophil counts and other biomarkers to gauge asthma-type inflammation.
Advanced Testing (if needed)
Occasionally, we perform sputum analysis or a bronchial challenge test to confirm mixed asthma-COPD physiology.
Treatment
Our Team offers a full range of care for asthma-COPD overlap syndrome.
1. Lifestyle and Diet Support
Help to quit smoking if needed
Pulmonary rehab and gentle exercise plans
Tips for eating anti-inflammatory foods like fruits and vegetables
Avoiding triggers such as pollen, dust, and fumes
2. Medications
Inhaled corticosteroids (ICS) to reduce airway inflammation
Long-acting bronchodilators (LABA or LAMA) for daily symptom control
Combination inhalers that address both asthma and COPD components
Biologic therapies for patients with severe or frequent flare-ups
3. Minimally Invasive or Advanced Procedures
Bronchial thermoplasty to treat severe asthma
Endobronchial valves to improve breathing in advanced COPD cases
Access to clinical trials for cutting-edge therapies
Dr. Nghia Nguyen, DO, is a board-certified gastroenterologist providing advanced digestive care in the Greater Houston area. He earned his medical degree from the Texas College of Osteopathic Medicine and completed both his Internal Medicine residency and Gastroenterology fellowship at the University of Texas at Rio Grande Valley. Dr. Nguyen specializes in treating conditions such as acid reflux, irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), and liver disorders.
Frequently Asked Questions
What makes ACO different from asthma or COPD alone?
ACO combines airway inflammation similar to asthma with irreversible airflow limitation typical of COPD. This overlap leads to more frequent flare-ups and calls for a specialized treatment approach.
Can I exercise if I have ACO?
Yes. Under Dr. Nguyen's guidance, a personalized pulmonary rehab and gentle exercise plan can safely strengthen your lungs and improve endurance.
What is the ICD-10 code for ACO?
There isn't a single code. Providers document both J45.9 (asthma) and J44.9 (COPD) together to accurately capture overlap syndrome.
Does ACO affect life expectancy?
With proactive care—including medication adherence, trigger avoidance, and regular follow-ups—many patients live normal, active lives.
Can I get biologic medications?
If your symptoms are severe or frequent, Dr. Nguyen may recommend biologic therapies tailored to your inflammatory profile and test results.
Does Houston weather make symptoms worse?
Hot, humid days, high pollen counts, and urban pollution can trigger flare-ups. Dr. Nguyen will help you develop strategies to minimize weather-related breathing difficulties.
How soon will I feel better?
Many patients notice relief within a few weeks of starting inhalers, pulmonary rehab, and lifestyle adjustments under Dr. Nguyen's care.
