The annual decline in lung function is similar between sickle cell disease and cystic fibrosis, according to a new study published in Blood Advances. These findings support the importance of routine spirometry evaluation in adults with sickle cell disease.

Even though there are no known therapies to stop the decline or increase lung function in adult patients with sickle cell disease, certain practices can be implemented to delay this decline as much as possible. These include smoking cessation, management of occupational exposures, and the investigation of comorbidities. It is therefore important to routinely evaluate lung function in these patients.

The American Society of Hematology recommends against the routine screening of lung function in individuals who are asymptomatic. However, there are similarities in terms of pulmonary complications between sickle cell disease and cystic fibrosis in which lung function testing is recommended at every routine clinic visit to closely monitor lung function decline in all patients.

Read more about sickle cell disease overview

To assess whether the annual decline in forced expiratory volume in 1 second (FEV1) is similar between adults with sickle cell disease and cystic fibrosis, a team of researchers led by Shaina Willen, MD, from UCSF Benioff Children’s Hospital in San Francisco, California conducted a retrospective cohort study at Vanderbilt University Medical Center in Nashville, Tennessee.

The researchers collected over 969 pulmonary function tests from patients with sickle cell disease and over 14,000 tests for patients with cystic fibrosis. Then, using statistical analyses, they predicted the change over time in at least 2 spirometry evaluations.

The results showed that the FEV1 declined by 23 mL per year in patients with sickle cell disease and by 26 mL for patients with cystic fibrosis. There was no statistically significant difference in the annual change in FEV1 between the 2 diseases. 

“While initial FEV1 is lower in individuals with [cystic fibrosis] than [sickle cell disease], the annual decline over time is similar between the two diseases,” the researchers concluded.


Hodges B, Ivy ZK, Cronin RM, Rodeghier M, DeBaun MR, Willen S. Annual decline in lung function in adults with sickle cell disease is similar to that observed in adults with cystic fibrosis. Blood Adv. Published online January 11, 2022. doi:10.1182/bloodadvances.2021006527