If you have asthma, you may notice that your symptoms are worse at night – you are not alone. More than five million people in the UK have asthma and night-time asthma, also known as nocturnal asthma, is thought to affect up to three quarters of them.
Symptoms of nocturnal asthma include coughing fits, tightness in the chest, wheezing and shortness of breath just before and during sleep. Sufferers can be woken up several times, leading to tiredness, poor concentration and difficulty controlling asthma symptoms during the day, in both adults and children. This can have a significant impact on quality of life.
More asthma-related deaths and severe attacks happen at night, so nocturnal asthma is a serious condition that requires preventative steps and effective treatment. The exact reason why asthma might be worse for some people at night is unclear although certain factors are thought to play a role and there are things you can do to minimise your risk.
Causes and triggers of Night-time asthma
It is not known exactly why asthma is worse at night for some people, although there are certain factors that can make asthma attacks at night more likely. Triggers for asthma attacks at night are:
- Sleeping position. Certain sleeping positions, such as lying on your side or your front, can constrict your lungs, potentially making nocturnal asthma symptoms worse. Meanwhile, sleeping flat on your back can cause mucus in your nose to drip to the back of your throat and trigger a night-time cough.
- Breathing in cold air. A cool room is better for sleep but your night-time asthma might be worse in winter or if you sleep in an air-conditioned room. This is because cold air is dry – loss of moisture and heat in the airways can trigger an asthma attack.
- Exposure to allergens at night. House dust mites in your bedding or mattress, and pet dander, dust particles or mould in your bedroom can all irritate your airways and make you more prone to nocturnal asthma.
- Exposure to allergens during evening. Being exposed to allergens in the evening , from pollen to pet hair, can cause a delayed or ‘late phase’ response. You may experience airway obstruction several hours later, increasing your risk of an asthma attack during the night.
- Poorly controlled day-time asthma. Not following your asthma treatment plan properly during the day can put you at greater risk of suffering from night-time asthma attacks.
- Lung function changes. Natural bodily processes during sleep can make you more prone to nocturnal asthma. Lung function is naturally lower at night. As muscles relax during sleep, the upper airway narrows and leads to increased resistance in the lungs. This means you are more likely to suffer breathing difficulties and coughing fits during the night.
- Hormonal changes. During sleep, your body goes through hormonal changes that might make your asthma worse. Some studies, for example, have shown that decreased levels of cortisol during sleep contribute to airway obstruction.
Nocturnal asthma symptoms
Asthma symptoms occur when the airway becomes inflamed and constricts to make breathing difficult. Common nocturnal asthma symptoms are:
- Shortness of breath
- Chest tightness
In addition, other effects of nocturnal asthma on adults and children include:
- Lack of concentration during the day
- Excessive daytime sleepiness
- Difficulty controlling daytime asthma symptoms.
If you have asthma symptoms at night, but have not been diagnosed with asthma, you should see a doctor or nurse specialist. If you do have a diagnosis, you should make sure that potential night-time triggers have been addressed in your asthma plan.
Certain groups of people with asthma are more likely to experience nocturnal asthma due to certain risk factors which include:
- Excess weight around the chest and abdomen might constrict the lungs while fatty tissue produces inflammatory substances that could affect lung function. Some studies have shown people with asthma who lost weight had improved lung function at night.
- Smoking damages your lungs and will make you more prone to asthma symptoms including asthma attacks at night.
- Allergic rhinitis. One study found poor treatment of allergic rhinitis was linked to a 50% increase in asthma symptoms at night. The condition causes excess mucus to accumulate during sleep and this irritates the throat, which could trigger a coughing fit.
- Sinusitis has been linked with more severe cases of asthma. The condition, a type of viral infection of the sinuses, causes a nasal discharge that can aggravate your asthma as you sleep and wake you with the need to cough.
- Obstructive sleep apnoea (OSA). With this condition, the throat muscles relax during sleep, obstructing the airways, and research has shown a link between OSA and nocturnal asthma.
- Acid reflux. People with asthma are twice as likely to develop a form of chronic acid reflux that flares up at night, known as gastroesophageal reflux disease (GERD). One theory is that acid reflux can cause a bronchial spasm making it harder to breathe and this is worse when you lie down.
- Although the evidence is still inconclusive, some research suggests that stress triggers an immune response that might inflame the airways, leading to an increased likelihood of an attack in people with asthma.
How to prevent night-time asthma
While there is no cure for asthma, there are plenty of way to help prevent night-time asthma and remedies to stop an asthma cough at night. Tips for reducing the symptoms of nocturnal asthma are:
- Keep your bedroom environment clean and free of allergens. Do not allow pets in your bedroom; wash bed linen regularly at a hot temperature to remove house dust mites; air your bedroom and treat any mould on walls; avoid using duvets and pillows with feathers.
- Regulate bedroom room temperature at night. Make sure windows are closed, avoid air conditioning and invest in an air purifier for better quality air in your bedroom.
- Treat underlying conditions: If you suffer from an underlying condition such as GERD, allergic rhinitis or obstructive sleep apnoea, make sure you are taking steps to treat and control it. Research shows, for example, that people who take medication for GERD have fewer asthma attacks and night-time asthma symptoms. Take the appropriate medication and any lifestyle steps such as dietary changes to ease acid reflux.
- Keep your reliever inhaler close by. Keep your inhaler next to your bed so that you can use it if you have a coughing fit during the night.
- Keep water by your bed. Sip some water when your symptoms start to flare up. Moisture will soothe the airways and help relieve your night-time cough.
- Breathing exercises. Different breathing techniques are used to alleviate asthma symptoms and can help you stop an asthma cough at night. If you wake up coughing, you could try a breathing exercise to help control your cough.
- Have an asthma review with your GP or practice nurse. They can check you are using your inhalers correctly and discuss any possible triggers for your nocturnal asthma.
- Follow an asthma treatment plan. Keep your asthma under control by using your medication properly, tracking your symptoms, following an effective asthma treatment plan and adjusting medication if necessary, with the advice of your doctor.
- Maintain a healthy weight. Eat a balanced diet and exercise to keep your weight under control.
- Quit smoking.
What is the best position to sleep with asthma?
Alleviating some of your nocturnal asthma symptoms can be as simple as changing your sleeping position. One study found that the supine sleep position (lying on your back) improved night-time asthma symptoms and constricts your lungs less than lying on your stomach or side.
The best sleeping position for asthma patients is to prop yourself up with extra pillows. This will help to keep the airways open and reduce your risk of a night-time cough.
Nocturnal asthma medical treatment
There is no cure for nocturnal asthma, although there are treatments to get it under control. Discuss your symptoms with your GP or asthma nurse and they will be able to recommend the best treatment plan for you. Medical treatment for nighttime asthma could include:
- Preventer inhaler. This delivers a dose of steroid medicine that you breathe in to damp down inflammation and swelling in the airways. Using a preventer inhaler regularly builds up protection so you are less sensitive to triggers. Good day-time control of your asthma will reduce flare-ups at night.
- Reliever inhaler. This delivers a dose of fast-acting medicine such as salbutamol that will open up the airways and help relieve the symptoms of nocturnal asthma. Keep it beside your bed so you can use it as soon as you have an attack at night.
- Combination inhalers. If your other inhalers are not helping, you might need a combination inhaler that mixes the medication and stops symptoms occurring while also providing relief if they do occur.
- Leukotriene Receptor Antagonists (LTRAs). This medicine is given in tablet-form and sometimes used in addition to inhalers to help with severe asthma symptoms and night-time attacks.