Recently, several reports out of Canada have revealed that Cystic Fibrosis patients there are leading increasingly longer, healthier lives than in other nations with high CF patient populations. Now, a new study entitled “A contemporary survival analysis of individuals with cystic fibrosis: a cohort study,” published yesterday in the European Respiratory Journal by a team of researchers from Toronto led by Anne Stephenson, further quantifies this trend, while also identifying risk factors associated with survival in the cystic fibrosis population.
CF is a genetic condition in which the lungs and digestive system become clogged with thick sticky mucus. Symptoms include persistent cough, recurring chest and lung infections, poor weight gain. Lung function often starts to decline in early childhood in people who have CF. Over time, damage to the lungs can cause severe breathing problems. Respiratory failure is the most common cause of death in people who have CF. Treatments may include nutritional and respiratory therapies, medicines, and exercise. As treatments for CF continue to improve, so does life expectancy for those who have the disease. Today, some people who have CF are living into their forties or fifties — or longer. Early treatment for CF can improve quality of life and increase lifespan.
Recently, the median age of survival in cystic fibrosis has increased. Known factors associated with poor survival include female sex, malnutrition, low lung function, certain infection and diabetes related with CF.
The team of researchers accessed the Canada CF Registry, a population-based cohort, and included 5,787 individuals (1990-2012) in their analysis. Using Cox proportional hazards models, the median survival age increased 49.7 years in 2012, up from 31.9 years in 1990. In addition, the median age at which Canadians with cystic fibrosis die has risen to 32 years in 2012 from 21.7 years in 1990. The death rate declined from 1.4 deaths per year in 1990 to 0.99 deaths per year in 2012.
Furthermore, the objective of the study was to identify risk factors associated with survival in a contemporary CF population, with results showing that malnutrition and pulmonary exacerbations are associated with an increase in the risk of death.
The sex gap in CF survival was explained by an increased prevalence of CFRD in females and increased mortality in women with CFRD. However, further studies are needed to better understand the sex–CFRD interaction.
Anne Stephenson, in a press release said, “the data showed increasing survival for all groups of CF patients, even people with the most severe mutations, indicating the improvements in median age of survival were not simply due to detecting milder cases or the inclusion of those milder cases in the CF Registry.”