Effects of clinical research participation on disease progression in cystic fibrosis

CF is an autosomal recessive disorder caused by mutations in the CFTR gene. The life expectancy for patients with CF remains severely shortened, with the median predicted survival for patients currently estimated at 36.5 years. For patients with a lifelimiting disease such as CF, the decision to participate in a clinical trial is often based on the desire to improve quality of life and/or increase the likelihood of long-term survival. Recent advances in CF care have increased the number of therapies available for CF patients which in turn has increased life expectancy and diminished disease progression. The CFF has developed a patient registry and has worked with individual CFFaccredited care centers in the US to approach all patients followed at these CF centers to participate in an observational prospective cohort study. Using data from 504 patients followed at Boston Children’s Hospital and submitted to the data registry maintained by the CFF, we examined disease progression, as measured by the decline in pulmonary function tests between 2007 and 2012 and compared multiple subsets of CF patients: those who participated in interventional studies, those who participated in observational studies only, and those who did not participate in any research studies. Results suggest a lower amount of lung function decline for adults who participate in interventional trials; however, the opposite pattern is true for children, with a higher amount of lung function decline seen for children who participate in interventional trials.