CPAP Effect on Cardiopulmonary Exercise Testing Performance in Patients with Moderate-Severe OSA and Cardiometabolic Comorbidities.

Background and Objectives: Obstructive sleep apnea (OSA) is associated with daytime somnolence, cognitive impairment and high cardiovascular morbidity and mortality. Obesity, associated cardiovascular comorbidities, accelerated erythropoiesis and muscular mitochondrial energetic dysfunctions negatively influence exercise tolerance in moderate-severe OSA patients. The cardiopulmonary exercise testing (CPET) offers an integrated assessment of the individual's aerobic capacity and helps distinguish the main causes of exercise limitation. The purpose of this study is to evaluate the aerobic capacity of OSA patients, before and after short-term continuous positive airway pressure (CPAP). Materials and Methods: Our prospective study included 64 patients with newly diagnosed moderate-severe OSA (apnea hypopnea index (AHI) 39.96 ± 19.04 events/h) who underwent CPET before and after CPAP. Thirteen patients were unable to tolerate CPAP or were lost during follow-up. Results: 49.29% of our patients exhibited a moderate or severe decrease in functional capacity (Weber C or D). CPET performance was influenced by gender but not by apnea severity. Eight weeks of CPAP induced significant improvements in maximal exercise load (Δ = 14.23 W, p = 0.0004), maximum oxygen uptake (Δ = 203.87 mL/min, p = 0.004), anaerobic threshold (Δ = 316.4 mL/min, p = 0.001), minute ventilation (Δ = 5.1 L/min, p = 0.01) and peak oxygen pulse (Δ = 2.46, p = 0.007) as well as a decrease in basal metabolic rate (BMR) (Δ = -8.3 kCal/24 h, p = 0.04) and average Epworth score (Δ = -4.58 points, p < 0.000001). Conclusions: Patients with moderate-severe OSA have mediocre functional capacity. Apnea severity (AHI) was correlated with basal metabolic rate, resting heart rate and percent predicted maximum effort but not with anaerobic threshold or maximum oxygen uptake. Although CPET performance was similar in the two apnea severity subgroups, short-term CPAP therapy significantly improved most CPET parameters, suggesting that OSA per se has a negative influence on effort capacity.

The correlation between the ankle-brachial index and the metabolic syndrome. .

UNLABELLED: On a global scale, the cardiovascular diseases constitute the prime factor of death and invalidity. The premature mortality percentage caused by these varies from 4% in high developed countries to 40% in underdeveloped countries. Atherosclerosis is the most important etiological factor. The presence of various degrees of atherosclerosis in a certain vascular area (in our case, the lower limb arteries), increases the probability of affecting other areas as well (coronary, cerebral, renal, mesenteric arteries). AIM: The evaluation and description of the correlations between the ankle-brachial index levels and the cardiovascular risk factors, taken individually or as part of the metabolic syndrome. MATERIAL AND METHOD: The values of the ankle-brachial index were divided in normal and abnormal. The evaluated cardiovascular risk factors were: age, sex, arterial hypertension, obesity, smoking, high levels of cholesterol and basal glucose, low levels of HDL-cholesterol. RESULTS: There were significant statistical differences between the normal ankle-brachial index lot and the one with abnormal values, specifically in patients with diabetes mellitus and metabolic syndrome. More so, the study demonstrates that the ankle-brachial index is considerably smaller in patients with metabolic syndrome. CONCLUSIONS: The simple measurement of the afore mentioned index, as a atherosclerosis marker for the lower limb arteries, represents an independent prediction over the metabolic syndrome and the conventional risk factors, in the development of the cardiovascular diseases. The routine measurement of this parameter in medical practice might imply the early diagnosis of high risk manifested cardiovascular disease patients.