The influence of various factors on the forced expiratory volume in 1 second in children and adults with cystic fibrosis not taking CFTR-modulators

One of the most important predictors of the prognosis of cystic fibrosis (CF) is the pulmonary function test – forced expiratory volume in 1 second (FEV₁). It is important for physicians to understand the factors associated with changes in FEV₁ in patients not receiving CFTR modulators.

The aim of this study was to identify factors influencing changes in FEV₁ in patients with CF not receiving CFTR modulators.

Methods. Retrospective analysis was conducted using medical records of patients (n = 225) under 18 years who received inpatient treatment in the pediatric department of the Russian Children’s Clinical Hospital, the Branch of the Russian National Research Medical University named after N.I.Pirogov, as well as patients over 18 years (n = 181) who were followed by specialists of the Pulmonology Scientific Research Institute under Federal Medical and Biological Agency of Russian Federation.

Results. Nutritional status and the nature of pathogenic microflora of the lower respiratory tract have a key impact on the FEV₁ indicator in childhood. In the group of adult patients, the leading role belongs to complications such as CF-associated diabetes mellitus and the presence of pneumothorax.

Conclusion. Regular monitoring of external respiratory function is an integral part of patient management in CF. This study demonstrates the relationship between FEV₁ and a number of factors in patients not receiving pathogenetic therapy.

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