If you know someone who sounds like an old car that’s failing to start – and it’s been going on all day, for weeks – tell them to see their doctor. Quicker than not.

According to a new report, a chronic cough is the No.1 symptom that prompts us to go to the doctor.

By definition though, we tend to let it drag on before taking action.

What is a chronic cough?

According to University of Queensland researchers, a chronic cough is defined as a daily cough lasting longer than four weeks in children and greater than eight weeks in adults.

In either case, that’s a significant amount of time for the problem to go unexplored and untreated.

The study authors have recommended that patients suffering from a chronic cough “should have that cough thoroughly investigated and X-rayed if there are any red flags for an underlying disease.”.

Associate Professor Julie Marchant is a paediatric respiratory physician at the Queensland Children’s Hospital. She is co-author of the recommendations. She and her colleagues write:

“Chronic cough results in significant health care costs, impairs quality of life and may indicate the presence of a serious underlying condition.”

What causes a chronic cough?

Chronic cough can be caused by asthma or allergies, chronic obstructive pulmonary disease (COPD), excessive smoking and air pollution.

But it’s not always a breathing issue. Digestive disorders such as gastroesophageal reflux disease can cause chronic coughing.

This occurs when stomach acid repeatedly flows back into, and irritating, the esophagus.

How common is the symptoms?

The study found that coughing is the most common symptom prompting Aussies to see a doctor, with 8.8 per cent of the population estimated to have a chronic cough.

The prevalence of chronic cough in adults has been estimated to be 9.6 per cent globally and 8.8 per cent in Australia.

Prevalence peaks among people aged in their 60s.

The condition is estimated to occur in:

• 3 per cent of people who have never smoked,
• 4 per cent who used to smoke,
• And 8 per cent who currently smoke.

Overall, chronic cough presents more commonly in middle-aged women.

In a recent study of Australian children presenting to emergency departments, 7.5 per cent had chronic cough, and 20–23 per cent had persistent cough at day 28.

The new recommendations include separate pathways for diagnosing a child or an adult.

They also suggest that Aboriginal and Torres Strait Islanders be considered a high risk group.

Indigenous at high risk

The prevalence of chronic wet cough in children living in Indigenous communities is around 13 per cent.

In the report, Associate Professor Marchant and her colleagues write:

“First Nations Australians are disproportionately affected by conditions that present with chronic wet cough, such as protracted bacterial bronchitis and bronchiectasis.”

“The mortality difference between First Nations and non-First Nations Australians with bronchiectasis is about 22 years.”

The authors advise that in 180 First Nations children, aged five years or more, who were presenting to primary care in urban Queensland for any reason, 24 per cent had a history of chronic cough in the previous 12 months.

The new recommendations were published in the Medical Journal of Australia.