A recent study published in the journal BMC Pulmonary Medicine investigated the presence of obstructive sleep apnea, nocturnal hypoxemia, and excessive daytime sleepiness in adults with cystic fibrosis (CF) and evaluated several clinical markers as potential predictors of these comorbidities.

For the purpose of this prospective, observational, and descriptive-analytical study, the researchers gathered a cohort of 52 adult people with CF (mean age 30.7±8.0 years) from the Adult Cystic Fibrosis Unit of the Ruhrlandklinik Essen, Germany, between September and December 2020. All participants were clinically stable with no signs of respiratory disease exacerbation prior to study initiation.

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The researchers first conducted full overnight polysomnography, after which they measured excessive daytime sleepiness through Epworth Sleepiness Scale (ESS) questionnaire.

They also collected demographic and clinical data such as body mass index (BMI), pulmonary function parameters including forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1) and residual volume (RV), as well as ear lobe capillary blood gases concentrations.

According to the results, 40% of the participants fulfilled the polysomnographic criteria for obstructive sleep apnea, while the presence of nocturnal hypoxemia was discovered in 25% of participants. 15% of the participants experienced excessive daytime sleepiness, yet a high ESS score was neither related to obstructive sleep apnea nor nocturnal hypoxemia.

The researchers found no significant variation in age, lung function, BMI, ESS score, sleep architecture, and sleep quality between patients who experienced obstructive sleep apnea and those who did not share the same symptoms. However, the awake oxygen levels of those with obstructive sleep apnea were considerably lower.

None of the clinical markers assessed was a significant predictor of obstructive sleep apnea, while nocturnal hypoxemia may be predicted by ppFEV1, awake pO2, and awake oxygen saturation.

“Based on our data, we suggest regular polysomnography screening to detect overnight sleep apnea and nocturnal hypoxemia in adult people with CF, regardless of disease severity. This could help to prevent medical deterioration due to undetected sleep-disordered breathing in people with CF,” Welsner and colleagues noted.

Reference

Welsner M, Dietz-Terjung S, Stehling F, et al. Obstructive sleep apnea and nocturnal hypoxemia in adult patients with cystic fibrosisBMC Pulm Med. Published online November 28, 2022. doi:10.1186/s12890-022-02243-0