Sleep disordered breathing in interstitial lung disease: A review

Abstract

Patients with interstitial lung disease commonly exhibit abnormal sleep architecture and increased sleep fragmentation on polysomnography. Fatigue is a frequent complaint, and it is likely that poor sleep quality is a significant contributor. A number of studies have shown that sleep disordered breathing is prevalent in this population, particularly in the idiopathic pulmonary fibrosis subgroup. The factors that predispose these patients to obstructive sleep apnoea are not well understood, however it is believed that reduced caudal traction on the upper airway can enhance collapsibility. Ventilatory control system instability may also be an important factor, particularly in those with increased chemo-responsiveness, and in hypoxic conditions. Transient, repetitive nocturnal oxygen desaturation is frequently observed in interstitial lung disease, both with and without associated obstructive apnoeas. There is increasing evidence that sleep-desaturation is associated with increased mortality, and may be important in the pathogenesis of pulmonary hypertension in this population.

Keywords: Sleep disordered breathing, Interstitial lung disease, Pulmonary fibrosis, Nocturnal hypoxia, Obstructive sleep apnoea

Core tip: This article reviews the literature on sleep disordered breathing in interstitial lung disease, seeking to define the important contributing factors and sequelae. The key concepts that are explored include the contribution of nocturnal hypoxaemia to the development of pulmonary hypertension, and the mechanisms behind the observed high prevalence of obstructive sleep apnoea in interstitial lung disease patients.