Daytime hypoxemia in chronic obstructive pulmonary disease (COPD) patients is common. The causes of daytime hypoxemia are varied and are linked to nocturnal breathing disorders. These nocturnal breathing disorders of COPD are: 1) obstructive sleep apnoea (OSA), 2) nocturnal oxygen desaturation (NOD) without CO2 retention and 3) nocturnal hypoventilation. OSA with COPD i.e. overlap syndrome is seen in overweight rather than obese patients. They do not have excessive daytime sleepiness unlike OSA alone hence it is easily missed. Continuous positive airway pressure (CPAP) is the treatment of choice in these patients. Nocturnal oxygen desaturation without CO2 retention is due to V/Q mismatch and is seen in those with respiratory COPD phenotype. Long-term oxygen therapy (LTOT) alone is adequate for patients who develop consequent daytime hypoxemia. Contrarily, daytime hypoxemia due to nocturnal hypoventilation is seen in systemic COPD phenotype and it responds to non-invasive ventilator (NIV) with LTOT. This review is aimed at deciding if CPAP, LTOT or NIV with LTOT is required in COPD patients with daytime hypoxemia.

Introduction: Obstructive sleep apnoea syndrome affects 4% men and 2% women. It is the most common sleep disordered breathing and is associated with recurrent episodes of upper airway collapse during sleep. Arousal from sleep is required to re-establish the airway patency. This distortion of sleep pattern, repetitive awakening and nocturnal hypoxia lead to pulmonary and systemic hypertension as well as other cardiac and metabolic complications. Cardiovascular disturbances like systemic hypertension, acute myocardial infarction, nocturnal arrhythmias, corpulmonale and sudden nocturnal death are serious complications of obstructive sleep apnoea syndrome. Aim: To study the association between cardiovascular abnormalities/ cardiovascular risk factors and apnoea hypopnoea index (AHI) in patients diagnosed with obstructive sleep apnoea syndrome. Methods and Material: 50 patients diagnosed with obstructive sleep apnoea syndrome were divided in to 3 grades-mild, moderate and severe OSAS as per American Academy of Sleep Medicine. Patients were interviewed in detail, clinically examined and investigated (random blood sugar, lipid profile, thyroid function tests chest roentgenogram, ECG and 2D echocardiogram). On basis of history, examination and investigations patients were diagnosed of having hypertension, diabetes mellitus, hypothyroidism, hyperlipidemia and ischaemic heart disease. The prevalence of these associated disease with OSAS and its statistical association with grades of severity of OSAS was calculated. Statistical Analysis: Frequency and Percentage table, association among study group: Chi-Square test and Fisher Exact test. Results: In our study the prevalence of hypertension was 48%, diabetes mellitus was 38%, hypothyroidism was 18%, hyperlipidaemia was 30% and ischaemic heart disease was 34%. 24% patients of OSAS in our study had history of smoking. 24% patients has ST-T changes on electrocardiogram, 18% had left ventricular hypertrophy and 18% had left ventricular ejection fraction less than 45% on 2D echocardiography. The prevalence of Pulmonary hypertension was 30%. Statistically significant co-relation was observed between hypertension, diabetes mellitus, hyperlipidaemia, ischaemic heart disease with grades of severity of OSAS. Conclusions: Cardiovascular abnormalities and risk factors are more common in obstructive sleep apnoea patients and hence patients should undergo periodic evaluation.

Introduction: Sleep is frequently complicated in military veterans with post-traumatic stress disorder (PTSD). Obstructive sleep apnea (OSA), a common sleep disordered breathing which affects mostly middle aged men, may be an important reason for sleep disturbances symptoms in military veterans. This study was conducted to compare the clinical features and polysomnographic parameters of OSA in PTSD veterans and control group. Materials: 26 PTSD veterans diagnosed with OSA by standard polysomnography were studied. Body mass index (BMI) was recorded and Epworth Sleepiness Scale, a questionnaire for evaluation of daytime sleepiness was applied. The control group was consisting of men matched for age who diagnosed also with OSA. Results: The mean age of veterans was 53.73 ± 8.7, and of the control group was 52.11 ± 6.2 years. The most common initial complaint in veterans was insomnia (57.5%) following by aggressiveness (14.5%), while non-veterans mostly complained from snoring (53.8%) and sleepiness (23%). Apnea-hypopnea index (AHI) was on average 38.8 ± 27.2. Mean BMI of veterans was 28.5 ± 5.7 and it was not related with AHI. Conclusions: Unlike most of patients with sleep apnea, veterans mainly complain of insomnia and aggression. Moreover, BMI cannot predict the severity of sleep apnea in such patients. Therefore, it is recommended that veterans should be carefully investigated for OSA, even in the absence of typical presentation of OSA.