Chronic cough is a significant public health burden, with prevalence ranging from 9% to 33% globally. A chronic cough is a cough that lasts eight weeks or longer in adults, or four weeks in children.
Chronic cough is associated with impaired quality of life , more than just an annoyance .It can interrupt your sleep and leave you feeling exhausted.
Terms to Describe Chronic Cough
When diagnosing cough, there are three lengths: "Acute cough" is one that lasts less than three weeks. "Subacute cough" is one that lasts three to eight weeks and "Chronic cough" lasts longer than eight weeks.
Refractory cough is the cough that hasn’t been controlled after multiple testing and specific treatments as well as having tried various over-the-counter treatments from your healthcare provider.
Types of Chronic Cough
"Symptomatic" chronic cough is caused by an underlying disease and can be treated once the disease is diagnosed.
"Refractory" chronic cough is a cough that persists despite guideline based treatment.
About half of the patients with chronic cough do not have any known cause . In the light of this evidence, chronic cough has been described as a distinct clinical syndrome, that is, the cough hypersensitivity syndrome.
Smoking: The foreign substances in tobacco smoke can lead to a “smoker’s cough” – a result of the airways constantly trying to clear itself of chemicals. Heavy smokers often develop chronic bronchitis after 40 years of age. Exposure to second-hand smoke can also increase a person’s risk. The smoke can irritate the airways and lead to a chronic cough as well as lung damage.
Exposure to chemicals in the air, such as from working in a factory or laboratory, can also lead to long-term coughing.
Asthma and/or allergies: Allergies can lead to swelling of the airways, post-nasal drip and resultant coughing. Poorly controlled asthma is another risk factor for chronic cough. In some people, asthma presents mostly as a cough (without the characteristic laboured breathing).
Irritants in the home or work environment: Exposure to dust, pollen, pet dander, chemicals, industrial pollution and other irritants can all increase the risk for chronic cough.
Chronic lung disease: Conditions such as emphysema and chronic bronchitis cause persistent irritation and inflammation in the airways, leading to chronic cough.
Gender: Women have a more sensitive cough reflex, increasing their risk for developing a chronic cough.
Obesity: A link between obesity and chronic respiratory diseases is increasingly being recognised. Obesity can also increase one’s risk for gastro-oesophageal reflux disease, which could lead to chronic coughing.
Angiotensin-converting enzyme (ACE) inhibitors are medications that help relax the veins and arteries to lower blood pressure. ACE inhibitors prevent an enzyme in the body from producing angiotensin II, a substance that narrows blood vessels. This narrowing can cause high blood pressure and forces the heart to work harder. Angiotensin II also releases hormones that raise blood pressure. Taking ACE inhibitors is a significant risk factor for coughing. About 20 percent of people who take ACE inhibitors develop a cough.
Gestational age, underlying medical conditions, prior wheeze and childcare attendance are risk factors for chronic cough in young children.
Fortunately, chronic cough typically disappears once the underlying problem is treated.
The prevalence of chronic cough differs with age, sex and geographical location. It is more common in females and in the elderly population. There are geographical differences in the prevalence of chronic cough with an estimated prevalence of 18.1% in Oceania, 12.7% in Europe, 11.0% in America, 4.4% in Asia and 2.3% in Africa .
Causes of Chronic Cough
Cough is an essential defense mechanism. However, chronic cough is a significant cause of morbidity. Previously, chronic cough was considered a consequence of various diseases, such as asthma/eosinophilic bronchitis, rhinitis and gastro-oesophageal acid reflux disease. Recent evidence, however, suggests that chronic cough is a clinical syndrome with distinct intrinsic pathophysiology characterised by neuronal hypersensitivity.
A variety of factors can cause a chronic cough. Sometimes, more than one factor may be responsible. Some of the more common causes of chronic cough include: asthma, one type of asthma, known as cough-variant asthma, chronic bronchitis, gastroesophageal reflux disease.
Lingering after-effects of infection. If a person has had a severe infection, such as pneumonia or the flu, they might still experience lingering effects that include a chronic cough. Even though most of their symptoms have gone away, the airways may still remain inflamed for some time.
Postnasal drip, also known as upper airway cough syndrome, a postnasal drip is the result of mucus dripping down the back of the throat. This irritates the throat and triggers a cough reflex.
Some less common causes of a chronic cough include: aspiration, bronchiectasis excess mucus production, bronchiolitis, cystic fibrosis, heart disease or heart failure and lung cancer.
Coughing can be problematic if it interferes with a person’s daily life. When you can’t sleep because of constant coughing, any aspect of your health that depends on the recovery aspects of sleep can suffer. In addition, you may be at risk of accidents or injury because you’re less alert and slow to respond to situations.
The tension created in your body as you cough can give rise to headaches. Soft tissue including muscles, blood vessels, and nerves may all be involved when a cough induces headache.
The constant jolting movements of a chronic cough can disturb the balance organs of the inner ear. While these effects aren’t usually severe, they can also cause nausea and vomiting.
Your cough may interfere with blood flow enough to cause brief spells of syncope, more commonly known as fainting, particularly if you have a forceful spell of coughing.
The membrane that covers the whites of your eyes is filled with tiny blood vessels. Chronic coughing may be enough to rupture some of these, creating minor bleeding that gives your eyes a bloody appearance.
Spasms of the abdominal muscles during coughing may lead to contractions of muscles controlling the bladder. Women sometimes have issues with urinary incontinence after menopause or pregnancy, so chronic coughing can aggravate it.
The chest contractions associated with a chronic cough may have enough force to break or crack the bones of your ribcage.
The strain of coughing could contribute to inguinal or femoral hernias, when an internal organ protrudes through a muscle wall.
Quit smoking, or don't start smoking, since this is the most common reason for chronic cough. If you are regularly near secondhand smoke, you can reduce the danger by moving away from the smoker and finding a smoke-free place, making sure guests to your home know they cannot smoke inside and not letting passengers smoke in your car — even with the window down.
Avoid contact with anyone you know who may have bronchitis or pneumonia.
Eat fruit and foods that contain fiber. Research suggests that a combination of fiber and flavonoids found in fruit may prevent chronic cough.
Avoid foods that can trigger acid reflux is one of the best ways to manage this condition and reduce the cough that accompanies it. The foods and beverages that most commonly trigger acid reflux include: alcohol, caffeine, chocolate, citrus foods, fried and fatty foods, garlic and onions, mint, spices and spicy foods, tomatoes and tomato-based products.
Drink plenty of water (at least eight glasses a day).Gargle with warm saltwater to help remove any mucus. Inhale steam. Avoid inhaling dust, smoke or other pollutants as much as possible. Use extra pillows at night to prop up your head and upper body.