Cystic fibrosis (CF) is an inherited disease, which is most common in white children and young adults, although it can affect people of any race.
It used to be thought of as a disease of the lungs and digestive system, but it is now known to affect most organs in the body.
With improvements in diagnosis and care, life expectancy is increasing progressively and CF has become a disease of adults. In a recent population sample from the European Union (EU), 47% of people with CF were aged over 18 years. However, only 5% were aged over 40 years.
Cystic fibrosis can affect several parts of the body;
- The lungs
- Digestive system
- Ears, nose and sinuses
It results in various symptoms and other conditions which may include:
- A cough producing phlegm or mucus, frequent respiratory infections and progressive breathlessness
- Difficulty absorbing food, leading to poor nutrition
- Cirrhosis, or scarring, of the liver
- Reduced fertility
Periods of worsening of symptoms are known as exacerbations or ‘lung attacks’. They can have a negative impact on a person’s quality of life and are associated with a faster decline in lung function.
Chronic, or persistent, infection cause progressive damage to the airways and lungs, including bronchiectasis and eventually lead to failure of the lungs due to their inability to maintain normal levels of oxygen and carbon dioxide in the body. Death may then follow unless lung transplantation is performed.
CF is usually caused by problems with a gene called cystic fibrosis transmembrane regulator (CFTR), which plays a key role in regulating salt and water transport across cells lining the airway and gut, for example. If this gene isn’t working properly there is a build-up of thick mucus in the airways such that bacteria and particles cannot be removed effectively.
CF is an inherited (genetic) condition; a large number of variations of the faulty gene have been identified and the severity of the condition depends on the variation.
There are no known environmental causes of the disease, although exposure to tobacco smoke, air pollution and allergens, may all contribute to the long-term progression of the condition.
New-born screening for CF can reduce prevalence by allowing couples to use information to make better-informed decisions about having another child and by identifying other carriers in the family.
Complete prevention would only be possible if the population was screened to find out who carries the gene. There is still debate amongst experts about whether this is justified, whether it would merely result in unnecessary anxiety and about what advice would be given to people who were found to be positive.
Diagnosis of CF can be achieved by screening new-born babies. A baby’s heel is pricked and a small sample of blood is taken. This is known as the heel-prick test. The genes in the blood sample can then be analysed. A sweat test should also be performed to confirm CF. This takes a sample of sweat that is sent to a laboratory for testing for high salt concentrations in the sweat.
Current treatment mainly focuses on alleviating the symptoms to help improve a person’s quality of life and slowing progress of the disease. However, new treatments correcting the basic defect are becoming available.
The best form of treatment is by a multidisciplinary team, including nurses, physiotherapists, dieticians, social workers and pharmacists. For the best results care should be provided in a specialist centre which should be have the expertise and facilities to manage all aspects of the disease.
Antibiotics, physiotherapy, avoiding smoking, and immunisation are all important aspects of management; physiotherapy is used to clear the abnormally thick mucus that accumulates in the lungs, with patients shown how to continue regular treatment at home. The cost of treating people with CF increases as the disease progresses. Some people with CF may also receive a lung transplant. In 2009, there were 133 known lung transplants performed in Europe for people with cystic fibrosis, (compared to 108 in 2007) and more than 800 patients with CF across Europe were living with transplanted lungs.
The cost of treatment is likely to increase as new drugs, targeting specific genetic mutations in different forms of CF, are being developed. The first such treatment (ivacaftor) has recently been introduced and others are likely to follow. Gene therapy, aimed at replacing the faulty gene in the airway cells is currently in clinical trial.
- European Cystic Fibrosis Society (ECFS) Registry collects data from 25,000 CF patients in 21 different countries
- On average men with CF live a couple of years longer than women
- With improving medical treatment, CF is changing from a disease of childhood into a disease of adults. Today, 42% of CF patients are aged over 18, 5% are aged over 40 years and in some countries, more than half of all CF patients are adults
- 0.6% of patients have an organ transplant each year but this number is increasing; in most transplant centre CF is now the commonest reason for lung transplantation
- Although many people with CF are in full-time education or employment, the proportions fall as the disease progresses
- Average life expectancy in most of Europe is now into the mid-30s and this is likely to continue increasing.
- 85% of people with CF have defective pancreatic function and require special dietary supplements so that they can properly digest food
- 15% of patients are hospitalised at least once per year
- There are proportionally more ‘elderly’ CF patients in western European countries than in eastern Europe due mainly to differences in specialised care and socioeconomic conditions
Current and Future Needs
- There is a need to ensure that specialised services for adults with CF are established in all European countries and that they offer standards of care similar to paediatric clinics
- A dedicated CF unit is essential for best care
- As there will be an increased demand for lung transplantation in the future, organ donation should be promoted to ensure supply can meet the demand
- Treatment has in the past been solely aimed at symptoms of CF. Future research needs to concentrate on correcting the underlying abnormalities - the first treatment that corrects the basic defect has been developed (Kalydeco ™ (Ivacaftor, VX-770)) for use in CF due one specific gene variant
- Patients should be genotyped to allow for better targeted treatments