When a chronic cough has you in a chokehold
Experts discuss what can be done, and a cure
GOT a nasty cough you just can’t shake? If so, you are one of an estimated 15 percent of people who suffer from a chronic cough – a cough lasting over eight weeks.
“Coughs are a protective measure, helping clear airways of mucus and debris,” explains Alyn Morice, a professor of respiratory medicine at the University of Hull.
“Most persistent coughs are caused by gastric reflux, which makes the upper airways hypersensitive, but they can also be caused by underlying disease.”
Sometimes no cause can be found.
The good news is that researchers at the University of Manchester have just developed a treatment that promises to banish irrepressible coughs for good.
Known as AF-219, the twicedaily pill works by blocking receptors on the throat that trigger the cough reflex. In trials, it reduced cough frequency by 75 percent.
“It is the most effective treatment for chronic cough that has ever been studied,” says Peter Barnes, a professor of respiratory medicine at Imperial College, London.
“Some coughs, such as those caused by the common cold, are essential because they help remove excess mucus from the lungs, easing breathing,” explains Barnes.
But, it’s important to find ways to treat coughs that don’t serve a useful purpose and can actually do harm.
The priority is to identify what’s causing the cough.
Diagnosis hinges on whether a chronic cough is either “wet/productive”, which means you produce phlegm or mucus, or “dry/ non-productive”, says Dr Omar Usmani, a consultant physician in respiratory medicine who runs the chronic cough clinic at the Royal Brompton Hospital.
Then, the patient’s full history will be taken to determine the cause. “It’s focused detective work,” says Usmani.
In some cases, the cough is simply due to hypersensitivity of the nerves lining the throat without any obvious reason. This is the type of cough AF219 was initially developed to help.
Here, with the help of some of the UK’s leading experts, is our guide to help you work out what’s causing your cough.
Note: “If a cough lasts more than eight weeks,” Morice says, “see your GP. A chest X-ray should be performed to rule out any serious problems. If you cough up blood, see your doctor immediately.” DRY COUGHS Gastro-oesophageal reflux
This is the most common cause of persistent cough, responsible for up to 70 percent of cases.
Acid reflux typically causes heartburn, but some people may also – or only – develop a persistent cough linked to stomach acid splashing into the oesophagus.
“A cough caused by acid reflux may sound explosive or guttural and sufferers often report a funny taste,” says Dr Richard Russell, honorary medical adviser at the British Lung Foundation,
“If it is associated with a hiatus hernia, where the stomach can protrude through the diaphragm, it can sound like barking,”
Treatment: “The most important thing to do is reduce the production of stomach acid, using proton pump inhibitors – omeprazole and pantoprazole, available over the counter,” explains Barnes.
Yet this only works in around 60 percent of cases. For the rest, the cough remains, probably because the sensitive cells in the lining of the gullet are still being stimulated by the contents of the stomach splashing up.
Losing weight can help, reducing pressure on the valve between stomach and oesophagus. It’s important to quit smoking and reduce alcohol consumption as both exacerbate heartburn. And avoid lying down for two to three hours after a meal to allow the stomach to empty.
Surgeons can also reconstruct the valve between the oesophagus and stomach to prevent leakage. POST-NASAL DRIP This is when mucus from the sinuses runs down the back of the throat, irritating cells in the larynx, triggering the cough reflex. The drip is typically caused by sinusitis, inflammation of the sinuses, infection or allergic rhinitis (inflammation inside the nose caused by pollen or another allergen).
“A post-nasal drip tends to cause spasmodic coughing, a coughing fit which can be quite uncomfortable,” says Dr Russell. “Symptoms tend to be worse at night time when someone has been lying down for a long period of time, allowing the mucus to build up. Another sign I look for is loss of smell,” he said.
Treatment: Treating the infection can stop the mucus drip – many over-the-counter drugs contain ephedrine to dry up secretions, while antibiotics can clear infection, explains Barnes.
For allergic rhinitis, a topical nasal steroid such as Beconase may dampen an allergic response. For a persistent problem, a minor operation can improve drainage from the sinuses, and this should help stop the cough, says Barnes.
Medication for another condition may cause a chronic dry cough, which is a side-effect of ACE (Angiotensin Converting Enzyme) inhibitors, a common heart drug, says Russell – an estimated 20 percent of people taking them develop a chronic cough. “Some asthma inhalers can cause a cough, either because of the powder or propellant,” he adds.
Treatment: Swopping medication may help. Around 90 percent of drug-related coughs settle with different drugs. ASTHMA/ALLERGIES Coughing caused by allergies and asthma often worsens at night (because our bodies produce fewer of the natural steroids that reduce inflammation).
“These coughs can be worsened by temperature changes and strong perfumes,” says Russell. Another symptom of asthma is wheeziness.
Treatment: “For asthma, doctors usually prescribe corticosteroids as a preventer inhaler to be used twice daily, and a reliever medication such as Salbutamol to be used when needed,” says Usmani.
Many asthma patients don’t realise they need to use their preventers to keep coughing at bay, and only use relievers.
Hayfever sufferers can get relief from nasal sprays that reduce inflammation or antihistamines. LUNG CANCER Thousands of people are diagnosed with lung cancer every year.
One of the earliest symptoms can be a persistent cough, which in later stages may involve coughing up blood, says Usmani.
“People with lung cancer can have a small niggly cough a bit like a smoker’s cough,” adds Dr Russell. “It is important to get it checked out and not ignore it. Advanced disease results in a whistling cough as the tumour invades the airways.”
Treatment: This depends on the type of lung cancer, but often involves surgery, radiotherapy and chemotherapy. MUCUS COUGHS VIRAL/BACTERIAL INFECTION
Most common coughs are caused by viruses, and last up to three weeks.
Bacterial infections, such as with the streptococcus bacteria, result in yellow or green mucus, and cause coughing and fever for a short period.
Coughing associated with infection tends to involve a lot of throat clearing, and sounds “chesty”.
Treatment: Viral coughs should clear without treatment within three weeks; long-lasting bacterial infections can be treated with antibiotics. – Daily Mail