Obstructive Sleep Apnoea in Patients with End-stage Lung Disease

What is end-stage lung disease? End-stage lung disease is the final stage of any lung problem, may it be obstructive or restrictive in nature. Obstructive lung diseases bring about obstruction in ventilation though airway spasm, mucous secretions, inflammation of the airways or destruction of the air spaces. These diseases include chronic obstructive pulmonary disease (COPD), sarcoidosis, cystic fibrosis and sleep apnoea.

Restrictive lung diseases, on the other hand, may be neuromuscular in nature, due to thoracic deformities, interstitial lung disease or mesothelioma. The problem with end-stage disease is that it can bring about respiratory failure, especially in the presence of other medical problems such as sleep apnoea.

But can sleep apnoea occur concomitantly with end stage lung disease (ESLD)?

A recent study by Romem et al published in the Journal of Clinical Sleep Medicine revealed that organic sleep disorders are common in patients with end-stage lung disease. The authors performed a retrospective study of 60 patients with ESLD referred for lung transplantation evaluation. Demographic, polysomnographic, spirometric, and medication utilization data were extracted and analyzed. The results showed that sixty-seven percent had respiratory disturbance index (RDI) of > 5 while 21% had RDI between 15 and 30 and while 21% had RDI > 30.

There was also increased periodic limb movement during sleep (periodic limb movement index ≥ 15/h sleep) in 21.7% of the subjects. An independent positive correlation between DLCO% and RDI was noted (r = 0.41, p < 0.01). Oxygen saturation was negatively affected by respiratory disturbance in these patients. The use of ACE inhibitors was also found to be associated with moderate-to-severe OSA.

So, what does this mean? This means that patients who are at high risk for developing end-stage lung disease should also be screened for sleep apnoea and should be treated as soon as possible. These patients include those who are at high risk for chronic obstructive pulmonary disease (COPD), cystic fibrosis, sarcodiosis and other obstructive lung diseases. Those who are at high risk for restrictive pulmonary disease such as those with neuromuscular problems, thoracic deformities, mesothelioma, interstitial thoracic deformities, mesothelioma and interstitial lung disease should also be evaluated for sleep apnoea. Those who are undiagnosed with these conditions should be vigilant about symptoms such as difficulty of breathing or dyspnea, cough, depression and/or anxiety, weight loss and anorexia, right sided heart failure, enlarged liver, and peripheral oedema. These signs and symptoms could indicate that you have respiratory problems which may soon lead to end-stage lung disease. If you have these symptoms you should consult your doctor for further assessment and treatment.

You can read more about these findings here:

http://www.ncbi.nlm.nih.gov/pubmed/23853563

Image courtesy of praisaeng / Freedigitalphotos.net

Reference:

Romem A; Iacono A; McIlmoyle E; Patel KP; Reed RM; Verceles AC; Scharf SM. Obstructive sleep apnoea in patients with end-stage lung disease. J Clin Sleep Med 2013;9(7):687-693.