The contribution of fatigue and sleepiness to depression in patients attending the sleep laboratory for evaluation of obstructive sleep apnea

Abstract

2 ABSTRACTPurpose: A high prevalence of depressive symptomatology has been reported amongst sufferers of Obstructive Sleep Apnea (OSA), but it remains unclear as to whether this is due to their OSA or other factors associated with the disorder. The current study aimed to assess the incidence and aetiology of depression in a community sample of individuals presenting to the sleep laboratory for diagnostic assessment of OSA.Methods: Forty-five consecutive individuals who presented to the sleep laboratory were recruited; of those, 34 were diagnosed with OSA and eleven were primary snorers with no clinical or laboratory features of OSA. Nineteen control subjects were also recruited. Patients and controls completed the Beck Depression Inventory (BDI), the Profile of Mood States (POMS), and the Epworth Sleepiness Scale (ESS) to assess their mood and sleepiness, prior to their polysomnography.Results: All patients reported significantly more depressive symptoms compared to healthy controls, regardless of their degree of OSA. There were no significant differences between OSA patients and primary snorers on any of the mood and selfrated sleepiness measures. Depression scores were not significantly associated with any of the nocturnal variables. Regression analysis revealed that the POMS fatigue subscale explained the majority of the variance in subjects" depression scores. Conclusions:Fatigue was the primary predictor of the level of depressive symptoms in patients who attended the sleep laboratory, regardless of the level of severity of sleep-disordered breathing. When considering treatment options, practitioners should be aware of the concomitant occurrence of depressive symptoms and fatigue in patients presenting with sleep complaints, which may not be due to a sleep disorder.

Higher Risk for Obstructive Sleep Apnea in Chronic Treatment-Resistant Depression

“…The results are also consistent with studies indicating that untreated OSA patients might show higher depressive symptoms (38)(39)(40). Several studies have shown that existence of treatment resistant symptoms in patients with OSA might be due to depression and not due to OSA per se (41)(42)(43).…”

“…Poor sleep quality, sleep fragmentation, and intermittent hypoxemia have been proposed to influence mood (17,18,41,43). The positive effect of continues positive airway pressure (CPAP) and oxygen supplementation treatment on psychological symptoms in patients with OSA and comorbid depression indicate that hypoxia might play an important role in depressive symptoms treatment-resistance (38,42,44).…”

Depression May Reduce Adherence during CPAP Titration Trial

“…A number of studies have reported depressive symptoms making greater contributions to fatigue in OSA, than OSA severity. [27][28][29][30] Fatigue and sleepiness are similar but distinctly different constructs, and the improvement of sleepiness on CPAP therapy may not be as salient if Depression Predicts Poor CPAP Adherence depression-related fatigue is present. 29,31 Secondly, depression may sensitize patients to CPAP side effects (mask discomfort, air leak, claustrophobia, nasal congestion), with studies demonstrating that depressed individuals tend to report more symptoms regardless of the physiological severity of the condition.…”

Sexual function in pre- and post-menopausal women with obstructive sleep apnea syndrome

“…27--29 In our study, BDI was not significantly different between the three OSA groups, presumably because of the fact that OSA and depression have certain symptoms that are common to both disorders. 30,31 Many patients who were referred to the sleep laboratory suffering from symptoms like fatigue, sleepiness and anxiety did not present any polysomnographic features of OSA, and these patients formed the control group. Therefore, our control group was healthy according to the AHI score and not according to OSA-like symptoms.…”