Lung function determinants and mortality of children and adolescents with cystic fibrosis in South Africa 2007-2016.

OBJECTIVES

Forced expiratory volume in 1 second (FEV1) is an important predictor of outcome in cystic fibrosis (CF). This study aimed to describe the change in lung function, nutritional status, and mortality of children with CF at a single center in Cape Town, South Africa, and identify factors associated with poor lung function and mortality.

METHODS

A retrospective study was conducted of children aged between 5 and 18 years between January 2007 and December 2016. At least two separate best annual FEV1 measurements were required for inclusion in the study.

RESULTS

A total of 143 children were followed up from which 107 study participants (median diagnosis age 5.5 months) were included. There was no statistically significant improvement from 2007 to 2016 in population mean FEV1 (2.5 ± 1.70 to -1.9 ± 1.70 [P = .1]) and body mass index (-0.7 ± 1.2 to -0.4 ± 1.2 [P = .3]) Z scores. FEV1 Z score declined by 0.17 per year. No significant correlation between FEV1 and age of diagnosis, sex, ethnicity, genotype, geographical location, pancreatic status, or infections was identified. On multiple stepwise regression analysis, FEV1 at age 6 was found to be the only independent predictor of mortality (adjusted odds ratio [95% CI] 0.5 [0.3-0.8]; P = .005).

CONCLUSION

FEV1 at age 6 was an independent predictor for CF-related mortality. Measurement of lung function in preschool children in SA with CF using more sensitive methods than spirometry is important to identify children at risk of poor outcomes.