Undiagnosed chronic obstructive pulmonary disease and overlapping obstructive sleep apnoea in patients with coronary heart disease
23 February 2017 (online)
Chronic obstructive pulmonary disease (COPD) and coronary heart disease (CHD) represent leading causes of mortality worldwide that share common aetiological features. Thus, we aimed to identify the prevalence of COPD and overlapping obstructive sleep apnoea in CHD patients as a function of their coronary symptomatology.
A total of 90 patients, hospitalized at the University Hospital of Bonn for coronary angiography conduction, were prospectively enrolled and underwent pulmonary function testing, as well as overnight screening for sleep-disordered breathing.
Overall, patients were late middle-aged (67.1 ± 10.7yrs), predominantly male (88.9%) and slightly overweight (BMI 28.0 ± 4.9 kg/m2). Of these, 53 (58.9%) presented with acute coronary syndrome (ACS) (17 unstable angina, 25 non ST-segment elevation myocardial infarction, 11 ST-segment myocardial infarction), 11 suffered from stable angina, whereas the remaining 26 lacked clinical symptoms and underwent coronary angiography for control reasons. 21 patients (23.3%) met the spirometric criteria for COPD (FEV1: 68.8 ± 9.7% of predicted); in 16 of these 21 patients COPD had not been previously diagnosed. The distribution of undiagnosed COPD was shifted towards the asymptomatic/stable angina patient subgroup (21.6% vs. 15.1% among ACS patients). As to somnological testing, sleep apnoea was present in 42.2% (n = 38) of the entire study population, of which 57.9% (n = 22) exhibited a predominantly obstructive genesis. Among those presenting sleep apnoea, the mean apnoea-hypopnoea index and oxygen desaturation index averaged 30.9 ± 8.1/h and 20.9 ± 9.2/h, respectively. 18 patients (20.0% of the entire study population) exhibited both COPD and overlapping OSA, of whom the vast majority initially presented with no/stable coronary symptoms.
COPD and overlapping OSA exhibit important prevalences in CHD patients, are largely undiagnosed and therefore undertreated. Their occurrence does not increase with impairing coronary symptomatology.