A study in Journal of Clinical Sleep Medicine shows that the complaints of fatigue and tiredness in patients with obstructive sleep apnea (OSA) improved significantly with good adherence to continuous positive airway pressure (CPAP) therapy, suggesting that - like the symptom of excessive daytime sleepiness - these complaints are important symptoms of OSA.
Results indicate that good adherence to CPAP therapy for an average of five or more hours per night resolved baseline complaints of fatigue in 45 of 80 participants (56 percent), tiredness in 56 of 96 participants (58 percent) and sleepiness in 48 of 72 participants (67 percent); improvement of each symptom was significantly better among CPAP-adherent participants than among inadequately treated subjects. A baseline complaint of lack of energy also was resolved in 47 of 100 participants with good CPAP adherence, but this improvement failed to reach statistical significance when compared with inadequately treated participants.
According to senior investigator Ronald D. Chervin, M.D., M.S., of the Michael S. Aldrich Sleep Disorders Laboratory in Ann Arbor, Mich., physicians should consider the possibility of OSA as a treatable underlying cause not just for the complaint of sleepiness, but also for the chief complaints of fatigue, tiredness and lack of energy.
"We found that sleep apnea patients who used their CPAP regularly, in comparison to those who did not, had much greater success in reducing their fatigue, tiredness and sleepiness," he said. "This suggests that sleep apnea may be the cause of these symptoms, as it is a cause of sleepiness."
The study involved 313 OSA patients with an average age of 54.7 years; 178 (56.9 percent) were men. It compared 183 participants who reported using CPAP for an average of five or more hours per night with 96 subjects who either had no active treatment (55 subjects) or reported using CPAP for an average of less than five hours per night (41 subjects); 34 participants were excluded from the analysis because they received a treatment other than CPAP.
Compared with inadequately treated patients, participants who had good adherence to CPAP had a higher severity of OSA at baseline and lower self-reported sleepiness at follow-up. Both before and after treatment, women reported a complaint of lack of energy statistically more often than men.
According to the American Academy of Sleep Medicine, OSA is a sleep-related breathing disorder that involves a decrease or complete halt in airflow despite an ongoing effort to breathe. It occurs when the muscles relax during sleep, causing soft tissue in the back of the throat to collapse and block the upper airway. This leads to partial reductions (hypopneas) and complete pauses (apneas) in breathing that can produce abrupt reductions in blood oxygen saturation. Most people with OSA snore loudly and frequently, and they often experience excessive daytime sleepiness.
The authors suggest that their findings are in agreement with previous research demonstrating that CPAP adherence is associated with improvements in OSA symptoms, daytime sleepiness, cognitive impairments, blood pressure and quality of life.