Cystic Fibrosis: “bigger” population
Once considered a paediatric disease, now it has better prognosis, with survival until adulthood. Let’s review friends and enemies of this important outcome.
It has been estimated that there are approximately 70.000 individuals affected by Cystic Fibrosis (CF) around the world; this number is likely underestimated. Once, their life expectation was short, because often they died at paediatric age (5 years), but today over half of them is adult (> 18 years) and it seems that they will be almost 75% between 2010 and 2025. This population grows in number and above all in ages. The increase of adult CF population is due not only to the new diagnosis at adult age, or the inclusion in national registries of patients with mild forms, but also to the improved survival of newborn with classic, severe, form of CF.
Some positive factors are early diagnosis (newborn screening), multidisciplinary care, nutritional supplementation, specific inhaled therapy, P. aeruginosa eradication, lung transplantation and it is expected that CFTR modulator therapies will bring further benefits.
What are the negative factors that threaten these patients’ life? The most important predictor of survival is lung function, especially the forced expiratory volume in 1 second (FEV1) < 30% predicted. Some negative factors are not understood completely yet, like sex (female). This gender difference could be explained by delayed diagnosis (and so it should disappear after the introduction of newborn screening) and by higher incidence of CF-related diabetes. Unfortunately, socioeconomic status affects the prognosis of CF, like of other chronic diseases.
Other prognostic factors are CFTR genotype, initial disease presentation, age, pulmonary exacerbations and specialized CF care center.
The harmonization in compilation of national registries will be important to recognize the best strategies to improve quality and length of life of patients with CF. The adult patients, the so called “survivors”, could be 50 years old and they have obviously different needs from 5 years old children. To fulfil these needs, it’s necessary a good handover between paediatricians and general doctors (Transition Medicine).
Stephenson AL et al. The changing epidemiology and demography of cystic fibrosis. Presse Med. 2017 Jun;46(6 Pt 2):e87-e95.