Europe reports the highest prevalence of chronic cough across the 7MM

Chronic cough is one of the most common reasons worldwide for obtaining medical care. There are multiple definitions for chronic cough, but it is generally defined as a cough lasting three months or more.

Across the seven major pharmaceutical markets (7MM), namely the US, 5EU (France, Germany, Italy, Spain, UK) and Japan, the highest total prevalence of chronic cough was seen in Europe, which is largely thought to be influenced by a combination of genetic and environmental factors.

Though there is limited data on the number of people suffering from chronic cough, a systematic review in 2015 estimated the global prevalence of this syndrome to be 10%.

Previously chronic cough was described as a symptom of other diseases, but due to its high prevalence, it is now considered its own entity. GlobalData epidemiologists have shown the total prevalence of chronic cough across the 7MM in 2020 (Figure 1).

The highest total prevalence in all ages was reported in Spain with 4.6%, and the lowest was in the US with 1.5%. Comparing prevalence between markets may help explain which factors increase the disease burden.

Environmental factors such as smoking and high levels of air pollution have been linked to an increased risk of developing a chronic cough. Spain’s high prevalence may be associated with smoking. World Bank data found 29.3% of the adult population in Spain were smokers in 2016, compared with 21.8% in the US.

Chronic cough is a common comorbidity in many respiratory conditions such as asthma and chronic obstructive pulmonary disease (COPD). The prevalence of COPD in the 5EU was estimated to be 12.3% in 2020, compared with 9.6% in Japan.

The role of ethnicity in developing chronic cough has also been considered. However, a study looking at cough reflex sensitivity between Caucasian, Indian and Chinese participants found no difference. Other demographic factors such as age and sex have been known to increase the risk of developing a chronic cough, so these should also be examined when analysing differences in prevalence estimates.

While the global prevalence of chronic cough is high, this syndrome is poorly recognised, so many people remain undiagnosed.

Further studies comparing the diagnosed prevalence of people with chronic cough across markets using universally accepted diagnostic criteria are crucial to understanding this syndrome better.

In areas where there is a low proportion of the population diagnosed, efforts should be made to raise awareness of this disease. Increased disease awareness at the population level will encourage people to seek medical attention when symptoms occur and increased physician awareness will mean fewer people are misdiagnosed.

To conclude, multiple factors are thought to influence the higher prevalence of chronic cough in Europe. However, due to a lack of prevalence data globally, no definitive causes can be found. More research will permit a better understanding of this condition and result in better treatment and prevention.