One and a half million people in Europe who have severe asthma live in fear of a fatal attack, researchers have warned.
Actress Charlotte Coleman died after a severe asthma attack
They say one person dies from asthma every hour in Western Europe.
But 90% of these deaths are considered preventable by the World Health Organization.
The European Federation of Allergy and Airways Diseases Patients' Association (EFA) was highlighting the issue to mark World Asthma Day.
In all, there are six million people living with asthma in Europe.
An EFA survey of 1,300 people with severe asthma in France, Spain, Germany, Sweden and the UK found one in four feel their condition is "life-threatening."
The UK has one of the highest rates of asthma in Europe, with 5.2 million people currently receiving treatment for the condition, including 2.6m with severe asthma.
It is estimated that around 20 million working days are lost due to asthma each year in the UK, and that the total cost of the condition is around 3.76 billion euros (approximately £2.55billion).
The EFA survey found 90% are receiving care which fails to reach at least one of five standards recommended by the Global Initiative for Asthma (GINA).
One in five also reported attacks which were so bad that they could not draw breath at least once a week.
People with uncontrolled severe asthma are much more likely to be hospitalised and die from an attack.
Symptoms include coughing, gasping for air and wheezing which can affect speech, cause regular sleeplessness and render people with the condition unable to breathe.
Attacks can be triggered by allergic reaction to triggers such as tobacco smoke, pollution and animal fur.
More than half the respondents say they suffer anxiety and stress because of their condition.
Over a third of those surveyed said their asthma prevented them going out and socialising with friends, one in five felt it damaged their career or their studies.
Seven in 10 said it stopped them enjoying sporting activities, even though research has shown active people can control their asthma symptoms more effectively and enjoy a healthier lifestyle
One respondent said "you are not free when you have this disease, it's a prison."
'Right to good care'
The EFA says there needs to be more awareness of the condition, better environmental policies and more funding for research and treatments
Svein-Erik Myrseth, president of the EFA, said: "We know that, tragically, one person in Western Europe dies every hour as a result of asthma and that 90% of these asthma deaths could be prevented through increased public awareness, better access to appropriate healthcare provision and changes in environmental and healthcare policy."
Amelia Curwen, Executive Director at Asthma UK said: "These results reinforce the findings of Asthma UK's 'Living on a Knife Edge' report launched in 2004, which outlined the picture in the UK.
"Every person with asthma has a right to good care and Asthma UK would like to see asthma high on the political agenda."
Professor Martyn Partridge , Asthma UK's chief medical advisor, said: "The UK has the highest rate of asthma in the world and until recently at least, they rates have been going up and up.
"We know that people with asthma often get just five or 10 minutes with a health professional every year."
He said that wasn't enough time for people to be given the advice they needed to manage their condition.