Overnight Changes in Lung Function of Obese Patients with Obstructive Sleep Apnoea

Abstract

Purpose Obstructive sleep apnoea (OSA) is a prevalent disorder, characterised by collapse of the upper airways during sleep. The impact of sleep-disordered breathing on pulmonary function indices is however currently not well described. The aim of the study was to evaluate diurnal change in lung function indices in a cohort of patients with OSA and relate pulmonary function changes to disease severity. Methods 42 patients with OSA and 73 healthy control subjects participated in the study. Asthma and COPD were excluded in all volunteers following a clinical and spirometric assessment. Spirometry was then performed in all subjects in the evening and the morning following a polysomnography study. Results There was no difference in evening or morning FEV 1 or FVC between patients and control subjects (p [ 0.05). Neither FEV 1 nor FVC changed in control subjects overnight (p [ 0.05). In contrast, FEV 1 significantly increased from evening (2.18/1.54-4.46/L) to morning measurement (2.26/1.42-4.63/L) in OSA without any change in FVC. The FEV 1 increase in OSA was related to male gender, obesity and the lack of treatment with statins or b-blockers (all p \ 0.05). A tendency for a direct correlation was apparent between overnight FEV 1 change and RDI (p = 0.05, r = 0.30).Conclusions Diurnal variations in spirometric indices occur in patients with OSA and FEV 1 appears to increase in subjects with OSA overnight. These changes occur in the absence of change in FVC and are directly related to the severity of OSA. These findings dictate a need to consider time of lung function measurement.

Complement system activation in obstructive sleep apnea

“…Disrupted sleep is a major component in the pathophysiology of OSA. Still, the number of studies investigating inflammatory biomarkers before and after night is low (Bikov et al, 2017;Jordan et al, 2005;Kunos et al, 2015;Mills, Natarajan, Von Kanel, Ancoli-Israel, & Dimsdale, 2009;Nobili et al, 2000). In contrast to the findings on CRP (Mills et al, 2009), we did not find an overnight change in C3a or SC5b-9 in the OSA or control groups.…”

“…Polysomnography was performed as it was described previously (Bikov et al, 2017;Kunos et al, 2015Kunos et al, , 2017 using Somnoscreen Plus Tele PSG (Somnomedics GmbH Germany). Electroencephalogram, electrooculogram and electromyogram, thoracic and abdominal respiratory excursions, breath sounds, nasal airflow, electrocardiogram and oxygen saturation were recorded according to guidelines (Kushida et al, 2005).…”

“…It is hypothesised that systemic inflammation may be a pathophysiological link between OSA and co-morbidities; however, this has not been investigated in detail. Although sleep deprivation in healthy subjects is associated with elevated CRP levels (Meier-Ewert et al, 2004), the effect of sleep on markers of systemic inflammation in OSA has not been extensively studied (Bikov et al, 2017;Jordan et al, 2005;Nobili et al, 2000).…”

Perception of circadian variation of symptoms in Chinese patients with chronic obstructive pulmonary disease

“…Furthermore, the incidence of OSA is not clear as our study did not monitor the sleep for all COPD patients. It is well known that OSA is common in obese population and FEV 1 was reported to increase overnight in OSA patients with obesity (20). However, the mean BMI of COPD patients enrolled in this study was only 23.…”

Pulmonary Function and Effects of Body Position in Patients with Obstructive Sleep Apnea

“…The PFT can also provide information on the lower respiratory tract, which may be involved in the pathogenesis of upper airway disease. Other studies also suggested that there are associations between OSA and intrathoracic airways [10][11][12].…”