Obstructive sleep apnea syndrome (OSAS) is a common disease characterized by repetitive partial or complete closure of the upper airway during sleep. Cardiovascular disturbances are the most important complications responsible for increased morbidity and mortality.
It is suggested that daytime somnolence, chronic fatigue, and nocturnal hypoxemia may further impair muscle function and decrease exercise fitness. The aim of this study was to evaluate cardiopulmonary response to exercise in OSAS patients. Hypertensive response to exercise was diagnosed in 39 of 111 patients (35%). Patients with severe sleep apnea were characterized by higher mean blood pressure at rest, at 25%, 50% of maximal work load, at peak exercise and at post-exercise recovery.
Several significant correlations between hemodynamic responses to exercise and sleep apnea severity were also noted. The conclusion was that exercise tolerance can be limited due to hypertensive response in about 20% of patients. Patients with severe OSAS have exaggerated hemodynamic response to exercise and delayed post-exercise blood pressure recovery.
Cardiopulmonary response to exercise seems to be related to sleep apnea severity. (Przybylowski T, Bielicki P, Kumor M, Hildebrand K, Maskey-Warzechowska M, Korczynski P, Chazan R: Exercise capacity in patients with obstructive sleep apnea syndrome. Journal of Physiology & Pharmacology. 58 Suppl 5(Pt 2):563-74, 2007 Nov.
This following study assessed risk factors and correlates of snoring and observed apnea. Parents and grandparents of students from 20 randomly selected primary schools in urban and rural areas of Kirikkale, Turkey were asked about respiratory diseases, psychological distress and sleep-related disorders, using the Respiratory Questionnaire, Hospital Anxiety and Depression (HAD) scale and Sleep Questionnaire, respectively, which were returned by their children.
Out of 13,225 parents and grandparents of primary school students 12,270 returned the questionnaires, for an overall response rate of 92.7%. Snoring and the observed apnea were more prevalent among subjects from rural than those from urban areas. Exposure to biomass smoke and smoking were associated with an increased risk of snoring and observed apnea, after adjusting for gender, age, body mass index, income and education in the multivariate linear model.
In all subjects, increases in performance ability, daytime sleepiness, psychological distress and dyspnea scores observed in categories indicating increases in snoring intensity and observed apnea frequency constituted a trend but did always not reach statistical significance. Lastly, prevalence of traffic accidents, falling asleep at the wheel and morning headaches increased with the increments of snoring intensity and apnea frequency.
It was concluded that exposure to biomass smoke in rural areas may account for the higher prevalence of snoring and observed apnea. Snoring intensity and observed apnea frequency may increase prevalence of traffic accidents along with many unfavorable symptoms. (Ekici M, Ekici A, Keles H, Akin A, Karlidag A, Tunckol M, Kocyigit P: Risk factors and correlates of snoring and observed apnea. Sleep Medicine 9 (3):290-296, 2008).