Neuropsychiatric manifestations of obstructive sleep apnea: a review

Cross talk mechanism of disturbed sleep patterns in neurological and psychological disorders

The incidence and prevalence of sleep disorders continue to increase in the elderly populace, particularly those suffering from neurodegenerative and neuropsychiatric disorders. This not only affects the quality of life but also accelerates the progression of the disease. There are many reasons behind sleep disturbances in such patients, for instance, medication use, nocturia, obesity, environmental factors, nocturnal motor disturbances and depressive symptoms. This review focuses on the mechanism and effects of sleep dysfunction in neurodegenerative and neuropsychiatric disorders. Wherein we discuss disturbed circadian rhythm, signaling cascade and regulation of genes during sleep deprivation. Moreover, we explain the perturbation in brainwaves during disturbed sleep and the ocular perspective of neurodegenerative and neuropsychiatric manifestations in sleep disorders. Further, as the pharmacological approach is often futile and carries side effects, therefore, the non-pharmacological approach opens newer possibilities to treat these disorders and widens the landscape of treatment options for patients.

The Prevalence of Anxiety and Depression Symptoms in Obstructive Sleep Apnea

Objectives

Mood disorders are common in obstructive sleep apnea (OSA), though the interactions are not well-understood. The objective of this study was to evaluate the relationship between anxiety and depression with OSA. 

Methods

Patients who presented to the sleep center underwent polysomnography (PSG). Records were included if the sleep study showed OSA (Apnea-Hypopnea Index (AHI) ≥5 events/hour). All patients completed an Epworth Sleepiness Scale (ESS) and Hospital Anxiety and Depression Scale (HADS). A score of 8 or higher on the respective portion of the HADS was abnormal.

Results

A total of 45 records were included, with 28 scoring positive for anxiety and 29 positive for depression. Patients with anxiety had lower AHI (median (interquartile ratio)) than those without (21.4 (9.6-41.3) vs. 50.5 (25.1-94.3); p=0.0076). The peripheral oxygen saturation (SpO₂) nadir (80 (74-84)% vs. 65 (57-76)%; p=0.0007) and time with SpO₂ <90% (11 (6-12) minutes vs. 36 (13-68) minutes; p=0.0002) were less abnormal in patients with anxiety. The anxiety score on the HADS weakly correlated with AHI (r = -0.29). Patients with depression were not significantly different than those without depression in AHI, SpO₂ nadir, and time with SpO₂ <90%.

Conclusions

Symptoms of anxiety and depression are both prevalent in patients with OSA. There is an inverse relationship between OSA severity and the presence of anxiety, suggesting that comorbid anxiety may prompt sleep evaluation in less severe disease. Depression symptoms did not demonstrate a similar relationship with OSA severity.

Sleep Disturbances in the Elderly

Sleep disturbances are a common presenting symptom of older-age adults to their physicians. This article explores normal changes in sleep pattern with aging and primary sleep disorders in the elderly. Behavioral factors and primary psychiatric disorders affecting sleep in this population are reviewed. Further discussion examines sleep changes associated with 2 common forms of neurocognitive disorder: Alzheimer disease and Lewy Body Dementia. Common medical illnesses in the elderly are discussed in relation to sleep symptoms. Nonpharmacological and pharmacologic treatment strategies are summarized, with emphasis placed on risk of side effects in older adults. Future targets are considered.

Personality, anxiety and mood traits in patients with sleep-related breathing disorders: effect of reduced daytime alertness

OBJECTIVE

The etiology of depression and personality disorders in patients with sleep-disordered breathing (SDB) is not well defined and it is still unclear if they are directly related to the severity of the disease. In this study we test the hypothesis as to whether daytime sleepiness largely contributes to appearance of mood disorders.

METHODS

Sixty patients diagnosed as having snoring (n=16) or OSA (n=44) were examined. Daytime sleepiness was assessed by the administration of the Epworth Sleepiness Scale (ESS) and by the Maintenance Wakefulness Test (MWT). The Hospital Anxiety (HAD-A) and Depression (HAD-D) Scale and the Temperament and Character Inventory (TCI) questionnaires were used for psychopathological evaluation.

RESULTS

The mean HAD-A score was 6.9+/-0.45 and the average HAD-D score was 4.6+/-0.48, with no significant difference between snorers and OSA patients. Anxiety was present in 16% of cases and depression in 7%. The HAD-D score was related to the ESS score (R=0.37, P=0.003), the mean sleep latency at the MWT (R=-0.34, P=0.04), and the mean low SaO(2), ESS score alone explaining the 17% of variance in the HAD-D score. Compared to controls, there were no differences in almost all TCI scores, with novelty-seeking temperament score higher in patients. No relationships were found between HAD or TCI scores and apnea density.

CONCLUSIONS

We conclude that among patients evaluated for SDB, higher depression scores show an association with reduced daytime alertness, which therefore may have important effects on mood.

Development of a disease-specific health-related quality of life questionnaire for sleep apnea

The Calgary Sleep Apnea Quality of Life Index (SAQLI) was developed to record key elements of the disease that are important to patients. All items felt to influence the quality of life of these patients were identified. Final questionnaire items were selected by interviewing 113 patients with sleep apnea and 50 snorers who rated each item on whether it was a problem and the importance of it to their overall quality of life. Items for the final questionnaire were selected based on the rank order of the frequency ximportance product. The rank ordering was similar across strata of disease severity and between sexes. The Calgary SAQLI has 35 questions organized into four domains: daily functioning, social interactions, emotional functioning, and symptoms. A fifth domain, treatment-related symptoms, can be added for clinical intervention trials to record the possible negative impacts of treatment. The SAQLI has a high degree of internal consistency, face validity as judged by content experts and patients, and construct validity as shown by its positive correlations with the SF-36 and the improvement in scores in patients successfully completing a 4-wk trial of continuous positive airway pressure. It includes items shown to be important to patients with sleep apnea and is designed as a measure of outcome in clinical trials in sleep apnea. Flemons WW, Reimer MA. Development of a disease-specific health-related quality of life questionnaire for sleep apnea.

Clinical prediction of the sleep apnea syndrome

Polysomnography, the standard diagnostic test for people suspected of having sleep apnea, is a limited resource due to its expense. Decisions about which patients to refer to a sleep center and which require polysomnography can be made based on an estimate of the probability that they have sleep apnea. Clinical features that are associated with the severity of sleep apnea, as judged by the apnea-hypopnea index, can be combined together using statistical modeling into a clinical prediction rule, whose diagnostic performance can be summarized by its sensitivity and specificity or by likelihood ratios. To date, at least seven different sleep apnea clinical prediction rules have been developed, most incorporate anthropomorphic variables such as the body mass index, waist circumference, and/or neck circumference, and some type of abnormal respiration during sleep (snoring, apneas, choking and/or gasping) witnessed by a bed partner. In general these rules have reasonably high sensitivities but only intermediate specificities, thus they can be useful in excluding the diagnosis but do not usually raise the probability of sleep apnea high enough to warrant initiating therapy without at least some type of additional testing to confirm the diagnosis. In isolation the apnea-hypopnea index is not an optimal indicator of disease severity, thus ultimately clinical decisions about the need for polysomnography and/or the need for treatment must take into account other important clinical information such as symptom severity, quality of life, and the presence or absence of comorbid illness.

Occurrence of Neuropsychiatric Symptoms at Low Levels of Occupational Exposure to Organic Solvents and Relationships to Health, Lifestyle, and Stress

The objective of this study was to elucidate the effects of alcohol consumption, medical disorders, stressful life events, and solvent exposure on neuropsychiatric symptoms in a population with low levels of occupational exposure to organic solvents. The prevalence of neuropsychiatric symptoms was assessed by Questionnaire 16 (Q16) in 54 miners under notice of dismissal and 124 men in an age-matched random sample from the local population. When the Q16 results were dichotomized at six symptoms (of the 16 possible), regular use of medicine was significantly related to the Q16 score, with an adjusted odds ratio (adjOR) of 4.0, 95% confidence interval (95% CI) 1.2-13. There were also positive relationships to the number of years in work with exposure to organic solvents (adjOR 2.2 per 10 years, 95% CI 1.3-3.8), liters of pure alcohol consumed per month (adjOR 2.8, 95% CI 0.78-10), and unemployment (adjOR 2.4, 95% CI 0.80-7.2). The influences on neuropsychiatric symptoms of various common exposures other than occupational solvent exposure must be considered when questionnaires are used for screening or for studies of possible neurotoxic effects in solvent-exposed workers.

Sleep apnea: a challenge in critical care

Sleep apnea, defined as the cessation of breathing for at least 10 seconds during sleep, can have detrimental effects on the critically ill. Three types of sleep apnea exist, the most common being obstructive sleep apnea. Though its prevalence is only 1% to 3% in adults, it is very important to diagnose it and treat it early in the critically ill because it causes respiratory failure and difficult weaning from mechanical ventilation. Its most characteristic manifestations are repetitive apneic episodes during sleep, snoring, and diurnal hypersomnolence. Complications of sleep apnea include dysrhythmias, systemic and pulmonary hypertension, hypoxia, hypoventilation, left ventricular dysfunction, and stroke. Treatment methods depend on the cause and include medications, surgery, and nasal continuous positive airway pressure. The main nursing role is astute assessment and early detection, proper respiratory management, provision of psychologic support, and patient and family teaching.

Potentially reversible dementia: a review

Potentially reversible dementia is reviewed with reference to diagnosis, causes and outcome. Many disorders which cause cognitive impairment, such as drug toxicity and depression, fail to meet diagnostic criteria for dementia. These tend to have the best prognosis. Studies of the neuropsychiatric syndromes associated with disorders causing potentially reversible dementias suggest that dementia is an infrequent outcome and when it does occur, few cases recover. Factors predictive of improvement are short duration of symptoms and mild degree of cognitive impairment, usually subcortical in type. It is suggested that potentially reversible cognitive impairment would be a more accurate term as many cases are due to delirium and depression. While cases of well established dementia do not require extensive investigation, all cases should have a thorough clinical assessment as in many instances dual pathology exists and all require psychosocial management.

Sleep apnea syndrome: symptomatology, associated features, and neurocognitive correlates

This article reviews the essential features, types, prevalence, pathophysiology, and neuropsychological correlates associated with the sleep apnea syndrome. Persons who experience the intermittent hypoxia and fragmented sleep characteristic of the sleep apnea syndrome tend to exhibit moderate symptoms of diffuse cognitive dysfunction as well as multiple emotional and psychosocial sequela. It is concluded that more research is required in order to elucidate the relationship between the hypoxic parameters and neurocognitive deficits seen in the sleep apnea syndrome, and that neuropsychological assessment might represent a means whereby the effectiveness of various treatments for sleep apnea may be evaluated.