"Cough cough cough, doctor, when will my cough stop?"

This is the 4601th article of Da Yi Xiao Hu

As a community general practitioner on the front line of clinical practice, I often encounter patients who cough continuously as soon as they enter the clinic. "Hello, is there anything I can help you with?" "Doctor, as soon as I entered your hospital, I smelled the disinfectant and my throat started to itch, and I couldn't help coughing. I also cough constantly when I smell something strange at home, and it's been going on for a long time. I went to many places and took several X-rays, and there was no problem, but I used many medicines and it didn't get better." I believe this is not an isolated case. Chronic cough has become a common problem that troubles many people. So what exactly is chronic cough?

1. "Doctor, what is a chronic cough?"

Usually, we divide cough into acute cough, subacute cough and chronic cough according to the duration of the disease. The so-called chronic cough refers to a cough with a duration of more than 8 weeks. Clinically, chronic cough is divided into two categories based on whether there are abnormalities in chest X-ray examination. One category is those with clear lesions on chest X-ray, such as pneumonia, tuberculosis, lung cancer, etc.; the other category is those with no obvious abnormalities on X-ray, with cough as the main or only symptom.

2. "Doctor, every time I smell something strange, I keep coughing. Why is that?"

There are many causes of chronic cough, common causes include postnasal drip syndrome (UACS), cough variant asthma (CVA), eosinophilic bronchitis (EB), gastroesophageal reflux cough (GERC), etc. The above causes account for about 70% to 95% of the causes of chronic cough.

(1) Postnasal drip syndrome

It refers to a syndrome in which nasal diseases cause secretions to flow back into the back of the nose and throat, directly or indirectly stimulating the cough receptors, leading to cough as the main symptom.

(2) Cough variant asthma

It is a special type of asthma, with cough as the only or main clinical manifestation, without obvious wheezing or shortness of breath, but with airway hyperresponsiveness. CVA is the most common cause of chronic cough. The results of a multi-center survey in China show that CVA accounts for about one-third of the causes of chronic cough.

(3) Eosinophilic bronchitis

It is a non-asthmatic bronchitis characterized by airway eosinophil infiltration and negative airway hyperresponsiveness, accounting for 13%-22% of the causes of chronic cough.

(4) Gastroesophageal reflux cough

It is a clinical syndrome characterized by coughing due to the reflux of gastric acid and other gastric contents into the esophagus. It is a special type of gastroesophageal reflux and a common cause of chronic cough. Symptoms of reflux include heartburn, acid reflux, belching, etc.

This shows that the causes of chronic cough are different for everyone. You cannot assume that coughing means lung infection, go to the hospital for an X-ray or CT scan, and ignore it if there is no problem. Patients can think about whether they have chronic rhinitis, chronic pharyngitis, allergic diseases, reflux esophagitis, etc. When you are not sure about the cause of your cough, you still need to seek help from a doctor and go to the hospital for relevant examinations to get a clear diagnosis and regular treatment.

3. "Doctor, besides taking X-rays, what other tests do we need to do?"

For the diagnosis of chronic cough, medical history is particularly critical. The doctor needs to know the duration, nature, and timbre of your cough; the amount, color, and properties of your sputum; the factors that induce or aggravate your cough, such as the effects of body position and accompanying symptoms; and whether you have a history of smoking, occupational or environmental stimuli exposure. These medical histories are of great value for diagnosis. In addition, patients with a history of special occupational exposure should also pay attention to the possibility of occupational cough.

Relevant examinations can be selected according to each patient's medical history, from simple to complex. EB and CVA are the most common causes of chronic cough, accounting for about 50% of the causes of chronic cough in China. Therefore, pulmonary ventilation function tests, bronchial provocation/dilation tests and induced sputum cytology are recommended as the first-line examinations for chronic cough.

Therefore, when doctors recommend that patients undergo pulmonary function tests, please do not think, “My film is fine, it should not matter, I will not do this test for the time being.” After you complete the pulmonary function test, you may find unexpected problems that you often overlook.

4. "Doctor, can my chronic cough be cured? I've taken a lot of medicine."

First of all, the cause of chronic cough should be clarified, and relevant treatment should be carried out according to the cause. If there are typical symptoms of rhinitis, sinusitis or postnasal drip, the postnasal drip syndrome can be treated first. If there are typical gastroesophageal reflux-related symptoms or cough after eating, gastroesophageal reflux cough should be treated first. When the doctor considers that the cause of the cough is cough variant asthma and uses hormone treatment, the patient does not need to worry or resist. Only regular treatment can have better effect. When the treatment is ineffective, it should be evaluated whether the diagnosis is wrong, whether the treatment method is correct, whether the treatment time is sufficient, and whether there are factors that affect the efficacy, such as occupational or environmental exposure factors.

5. "Doctor, is there anything else we need to pay attention to in our lives?"

(1) Ensure environmental hygiene

When patients have chronic coughs, it is very important to clean their homes or workplaces. Open windows for ventilation every day, avoid irritating odors, and remove dust from the environment. Pay attention to the use of humidifiers, as high indoor humidity may aggravate coughs.

(2) Pay attention to dietary adjustment

People with chronic cough can eat more lung-moistening foods for dietary supplements. Severe cold and dampness in the body may cause coughs to worsen. Eating more foods that remove dampness and promote urination may also have a good effect. Eat more foods that are easy to digest and rich in vitamins. However, it should be noted that if you are allergic to milk, eggs, seafood, fish, etc., you should limit the intake of these foods.

(3) Drink more warm water

Drinking warm water when you have a chronic cough can make it easier to expel phlegm.

"Ahem, doctor, after listening to these words today, I suddenly understand. I have confidence that I can cure this chronic cough." Yes, chronic cough is not a particularly big problem, but we cannot ignore it. When encountering the problem of chronic cough (coughing > 8 weeks), patients should seek help from doctors as soon as possible and tell the doctor the complete course of their illness so that the doctor can make a judgment based on your medical history, give corresponding auxiliary examinations, help you determine the cause of chronic cough, and give regular treatment. We believe that your "cough cough cough" will stop one day.

Author: Sichuan North Road Community Health Service Center, Hongkou District, Shanghai

Dong Yangyang Attending Physician