Impaired Daytime Functioning Research Articles

Sleep-disordered breathing and insulin resistance in middle-aged and overweight men.

Sleep-disordered breathing is a prevalent condition associated with impairment of daytime function and may predispose individuals to metabolic abnormalities independent of obesity. The primary objective of this study was to determine the metabolic consequences and community prevalence of sleep-disordered breathing in mildly obese, but otherwise healthy, individuals. One hundred and fifty healthy men, without diabetes or cardiopulmonary disease, were recruited from the community. Measurements included polysomnography, a multiple sleep latency test, an oral glucose tolerance test, determination of body fat by hydrodensitometry, and fasting insulin and lipids. The prevalence of sleep-disordered breathing, depending on the apnea-hypopnea index (AHI) cutoff, ranged from 40 to 60%. After adjusting for body mass index (BMI) and percent body fat, an AHI gt-or-equal, slanted 5 events/h was associated with an increased risk of having impaired or diabetic glucose tolerance (odds ratio, 2.15; 95% CI, 1.05-4.38). The impairment in glucose tolerance was related to the severity of oxygen desaturation (DeltaSa(O(2))) associated with sleep-disordered breathing. For a 4% decrease in oxygen saturation, the associated odds ratio for worsening glucose tolerance was 1.99 (95% CI, 1.11 to 3.56) after adjusting for percent body fat, BMI, and AHI. Multivariable linear regression analyses revealed that increasing AHI was associated with worsening insulin resistance independent of obesity. Thus, sleep-disordered breathing is a prevalent condition in mildly obese men and is independently associated with glucose intolerance and insulin resistance.

Sleep quality and daytime function in adults with cystic fibrosis and severe lung disease.

It was hypothesized that adult cystic fibrosis (CF) patients with severe lung disease have impaired daytime function related to nocturnal hypoxaemia and sleep disruption. Nineteen CF patients (forced expiratory volume in one second 28+/-7% predicted) and 10 healthy subjects completed sleep diaries, overnight polysomnography (PSG), and assessment of daytime sleepiness and neurocognitive function. CF patients tended to report more awakenings (0.7+/-0.5 versus 0.3+/-0.2 x h(-1), p=0.08), and PSG revealed reduced sleep efficiency (71+/-25 versus 93+/-4%, p=0.004) and a higher frequency of awakenings (4.2+/-2.7 versus 2.4+/-1.4 x h(-1), p=0.06). Mean arterial oxygen saturation during sleep was lower in CF patients (84.4+/-6.8 versus 94.3+/-1.5%, p<0.0001) and was associated with reduced sleep efficiency (regression coefficient (r)=0.57, p=0.014). CF patients had short sleep latency on the multiple sleep latency test (6.7+/-3 min). The CF group reported lower levels of activation and happiness and greater levels of fatigue (p<0.01), which correlated with indices of sleep loss, such as sleep efficiency (r=0.47, p=10.05). Objective neurocognitive performance was also impaired in CF patients, reflected by lower throughput for simple addition/subtraction, serial reaction and colour-word conflict. The authors concluded that adult cystic fibrosis patients with severe lung disease have impaired neurocognitive function and daytime sleepiness, which is partly related to chronic sleep loss and nocturnal hypoxaemia.

Advances in sleep medicine

Sleep medicine is a new area in respiratory clinical practice, particularly in the UK. This review highlights the recent advances made in sleep apnoea/hypopnoea syndrome (SAHS) over the last few years, particularly in diagnosis and treatment, and its well-established role as a cause of impaired daytime performance and road traffic accidents, in addition to the associated increased risk of morbidity and mortality from cardiovascular disease.

Neuroticism and Sleep-related Problems in Adolescence

To examine the relationship between neurotic personality characteristics and sleep habits/problems. A population-based cross-sectional study. NA. Nine hundred sixty five students from two junior high schools in Taipei and their parents were randomly selected in December 1993 for inclusion in the study. The response rate was 96.4% (930) for students and 88.6% (855) for parents. NA. Students were administered a sleep habit questionnaire and the Junior Eysenck Personality Inventory (JEPI) at both junior high schools in Taipei. For the JEPI, high and low neuroticism was operationally defined as scores that were one or more standard deviation above or below the sample mean, respectively. This yielded two extreme groups: high neuroticism group (n=183) and low neuroticism group (n=163). The high neuroticism group went to bed later and slept less than did the low neuroticism group. Using logistic regression, adjusting for sex and years at junior high school, the high neuroticism group had significantly different sleep habits and school performance from the low neuroticism group. Subjects in the high neuroticism group had significant risk of feelings of sleep insufficiency, tiredness, moodiness, and difficulty waking up in the morning; they also had more daytime sleepiness than did those in the low neuroticism group. The high neuroticism group also suffered from more sleep-related problems than did the low neuroticism group. The findings support the hypothesis that a high neuroticism score is associated with going to bed late on school days, short sleep duration, different sleep habits, sleep problems, and impaired daytime function in comparison with a low neuroticism score.

Sleep disorders in the elderly

Sleep disorders are common among elderly people, affecting about 50% compared with about 26% of younger adults. About two-thirds of residents in long-term care have sleep disturbance (Karacan &amp; Williams, 1983; Becker &amp; Jamieson, 1992). This high prevalence of sleep disorders results in excessive daytime napping, fatigue, cognitive impairment, increased psychiatric morbidity and increased prescribing of hypnotics, with an associated increase in mortality (Kripke et al, 1979). Karacan &amp; Williams (1983) quote figures varying from 26 to 100% for the prescribing of hypnotics to residents in institutional care. This has major implications. There is a risk of both accidental and deliberate overdose. There may be interactions with other drugs and a hangover effect can impair daytime functioning. Excessive sedation can make the patient difficult to rouse in an emergency. Dependence may occur and the drugs may further disrupt sleep. They also increase the likelihood of sleep apnoea.

Does arousal frequency predict daytime function?

Patients with the sleep apnoea/hypopnoea syndrome (SAHS) have impaired daytime function with demonstrable sleepiness and impaired cognition. The hypothesis that brief arousals from sleep cause these daytime impairments was tested. One hundred and fifty patients with sleep disordered breathing were studied prospectively, comparing overnight polysomnography with daytime measures of objective sleepiness, psychological well-being and cognitive performance. Significant, but weak (r2<0.1), relationships were seen between several nocturnal measures (apnoea/hypopnoea index, arousals and desaturation variables) and daytime measures of quality of life, well-being, subjective sleepiness, symptoms and cognitive performance. The only significant relationship between nocturnal variables and objective sleepiness was a very weak correlation (r2<0.05) between the lowest oxygen saturation and mean maintenance of wakefulness test (MWT) result. The MWT was better correlated with daytime function than the multiple sleep latency test. This study shows a lack of strong relationships between conventional nocturnal measures and daytime function in patients with sleep disordered breathing.

Sleep fragmentation and daytime vigilance in patients with OSA treated by surgical maxillomandibular advancement compared to CPAP therapy.

Impaired vigilance is a frequent daytime complaint of patients with obstructive sleep apnoea (OSA). To date, continuous positive airway pressure (CPAP) is a well established therapy for OSA. Nevertheless, in patients with certain craniofacial characteristics, maxillomandibular advancement osteotomy (MMO) is a promising surgical treatment. Twenty-four male patients with OSA (pretreatment respiratory disturbance index (RDI) 59.3 SD +/- 24.1 events/h) participated in this investigation. The mean age was 42.7 +/- 10.7 years and the mean body mass index was 26.7 +/- 2.9 kg/m2. According to cephalometric evaluation, all patients had a narrow posterior airway space, more or less due to severe maxillary and mandibular retrognathia. All patients except two were treated first with CPAP for at least 3 months and afterwards by MMO. Two patients only tolerated a CPAP trial for 2 nights. Polysomnographic investigation and daytime vigilance were assessed before therapy, with CPAP therapy and 3 months after surgical treatment. Patients' reports of impaired daytime performance were confirmed by a pretreatment vigilance test using a 90-min, four-choice reaction-time test. The test was repeated with effective CPAP therapy and postoperatively. Daytime vigilance was increased with CPAP and after surgical treatment in a similar manner. Respiratory and polysomnographic patterns clearly improved, both with CPAP and after surgery, and showed significant changes compared to the pretreatment investigation. The RDI decreased significantly, both with CPAP (5.3 +/- 6.0) and postoperatively (5.6 +/- 9.6 events/h). The percentages of non-rapid eye movement Stage 1 (NREM 1) sleep showed a marked decrease (with CPAP 8.2 +/- 3.6% and after MMO 8.2 +/- 4.4% vs. 13.3 +/- 7.4% before treatment), whereas percentages of slow wave sleep increased significantly from 8.0 +/- 6.1% before therapy to 18.2 +/- 12.8 with CPAP and 14.4 +/- 7.3% after MMO. The number of awakenings per hour time in bed (TIB) was significantly reduced after surgery (2.8 +/- 1.3), compared to both preoperative investigation (baseline 4.2 +/- 2.0 and CPAP 3.4 +/- 1.5). Brief arousals per hour TIB were reduced to half with CPAP (19.3 +/- 20.0) and after MMO (19.7 +/- 13.6), compared to baseline (54.3 +/- 20.0). We conclude that the treatment of OSA by MMO in carefully selected cases has positive effects on sleep, respiration and daytime vigilance, which are comparable to CPAP therapy.

The effect of nonvisible sleep fragmentation on daytime function.

Patients with sleep apnea/hypopnea syndrome (SAHS) suffer from impaired daytime function that correlates with hypoxemia and visible electroencephalographic (EEG) arousals. However, not all breathing irregularities during sleep terminate with visible EEG arousal. We hypothesized that sleep disturbance without visible EEG change may impair daytime function. Twelve normal subjects spent two pairs of 2 nights each in the laboratory. The first night of each pair was for acclimatization. On the second night, subjects either slept undisturbed or had sleep fragmented every minute to cause a transient increase in arterial blood pressure or increase in heart rate without visible EEG arousal. We tested daytime function after each study night. We presented 253 +/- 23 tones (mean +/- SD), 79 +/- 7% of which did not cause visible EEG arousals. Fragmentation did not alter total sleep time (undisturbed: 419 +/- 27 min; fragmented: 414 +/- 32 min; p = 0.5) or arousal frequency (undisturbed: 22 +/- 4/h; fragmented: 25 +/- 6/h; p = 0.4). Fragmentation reduced slow-wave sleep (undisturbed: 24 +/- 5%; fragmented: 20 +/- 4%; p < 0.01), mean sleep onset latency on the multiple sleep latency test (MSLT) (undisturbed: 8.0 +/- 3.1; fragmented: 6.2 +/- 2.1 min; p = 0.01) and the maintenance of wakefulness test (MWT) (undisturbed: 29.0 +/- 10.0 min; fragmented 25.7 +/- 9.7 min; p = 0.04). Fragmentation decreased hedonic tone at 7 A.M. (27 +/- 4, 25 +/- 6; p = 0.03). Nonvisible (autonomic) sleep fragmentation makes normal subjects sleepier and impairs their mood.

Is hypnotic withdrawal facilitated by the transitory use of a substitute drug?

1. 1. Purpose: Long-term consumption of hypnotics may lead to various side-effects, including impaired daytime and cognitive functioning and increased risk of accidents. Unfortunately, few guidelines exist for physicians to apply when attempting to withdraw hypnotics from patients. This study investigated whether withdrawal is facilitated by using zopiclone as a substitute drug and evaluated abrupt and gradual substitution techniques. 2. 2. Methods: This open, multicentre and randomized study involved 1,002 male and female outpatients aged 18 years or over recruited by psychiatrists in Lyon, France. Patients had a mean age of 44 years, and 65.9% were women. Outpatients were chronic insomniacs being treated with a hypnotic for at least three weeks. The study included a substitution (D0-D35) and a withdrawal (D36-D56) stage. Patients were randomly drawn into three parallel groups: Group A underwent gradual substitution of zopiclone for the initial BZD; Group B was subjected to complete and immediate withdrawal of the initial BZD in favor of zopiclone; and Group C remained on the initial BZD, though told otherwise. The withdrawal stage began on D36 with a 50% reduction in medication and ended on D50 with complete withdrawal. 3. 3. Results: Groups A (gradual substitution) and B (abrupt substitution) presented a net improvement in sleep during the substitution stage. However, Group B displayed a better improvement in sleep-onset period, a decrease in nocturnal awakenings and an increased quantity of sleep. In the withdrawal stage, Groups A and B were similar but Group C displayed a deterioration in sleep. Following the withdrawal stage, 29% of patients in Group C, 18% in Group A and 19% in Group B resumed hypnotic use. 4. 4. Conclusions: Discontinuation of this type of medication is possible in over three quarters of cases, provided that the prescribing physician adheres to a precise withdrawal protocol. Patients on zopiclone were less likely to resume consumption of hypnotics during the week of full withdrawal and were more satisfied with sleep than when treated with a BZD hypnotic. Finally, the results of the study showed that abrupt substitution yielded better results for chronic users of hypnotics.

Sleep-disordered breathing and systemic hypertension in the older male.

To investigate the relationship between sleep-disordered breathing (SDB) and essential hypertension in a population of older male hypertensives. One-hundred forty consecutive older hypertensive males. Monitoring of sleep-related breathing abnormality with a portable sleep apnea monitor (level III device). Assessment of complaints related to sleep quality using a validated questionnaire. Systemic arterial blood pressure according to WHO standards and biochemical analyses. SDB was defined as more than 10 abnormal respiratory events per hour of sleep. Prospective investigation on a retrospective cohort. Veterans Administrations hypertension clinic. SDB was diagnosed in 80% of this older, hypertensive, male population. Thirty-four percent of all study subjects presented with severe SDB, with more than 30 abnormal respiratory events per hour of sleep. Subjects with SDB were significantly heavier (BMI = 30.0 +/- 5.2 kg/m2) than subjects without SDB (BMI = 26.8 +/- 5.1 kg/m2, P = .004). Furthermore, subjects with SDB slept significantly longer (by a mean of 46 minutes/night, P = .027) and complained significantly more often of daytime sleepiness than subjects without SDB (P = .018). Fifty percent of all 140 subjects snored more than 10% of the total sleep time, and 26% snored for more than one-third of the night. No significant differences in blood pressure values were observed in subjects with compared with subjects without sleep-disordered breathing. However, a considerable number of subjects presenting with hypertensive blood pressure values despite treatment could be identified. Subjects presenting with hypertensive blood pressure values had a significantly higher severity index of SDB than subjects with normotensive blood pressure values (P = .047). This investigation supports data showing that undiagnosed SDB is a common phenomenon in older male individuals, leading to impaired daytime functioning and impairment of overall quality of life. More importantly, our data suggests that untreated SDB may have an adverse effect on the efficacy of antihypertensive treatment in hypertensive individuals with sleep-disordered breathing.

The effect of sleep fragmentation on daytime function.

Patients with the sleep apnea/hypopnea syndrome suffer from impaired daytime function. This has been attributed to both sleep fragmentation and hypoxemia. To help understand which is casual, we studied the effects of sleep fragmentation alone on daytime function. Sixteen normal subjects were studied on two pairs of two nights. The first night of each pair was for acclimatization, and on the second the subject either slept undisturbed or had sleep fragmented with sound pulses every 2 min. Sound volume and duration was titrated to cause a return to theta or alpha rhythm on the EEG for at least 3 s. Study nights were followed by daytime testing of psychometric function and mood and by a multiple sleep latency test (MSLT) and a maintenance of wakefulness test (MWT). Total sleep time did not differ between study nights (400 +/- 20 SD min undisturbed, 396 +/- 24 min fragmented; p = 0.6). Fragmentation decreased sleep latency on both the MSLT (11 +/- 3, 7 +/- 2 min; p = 0.001) and the MWT (34 +/- 8, 24 +/- 10 min; p<0.001). Energetic arousal (22 +/- 4, 19 +/- 4; p = 0.005) and hedonic tone (29 +/- 4, 27 +/- 4; p = 0.05) decreased after fragmentation. Fragmentation impaired daytime function adjudged by the Trailmaking B (p = 0.05) and PASAT 4-s tests (p<0.03). One night of sleep fragmentation makes normal subjects sleepier during the day, impairs their subjective assessment of mood, and decreases mental flexibility and sustained attention.

Weight loss for obstructive sleep apnea: The optimal therapy for obese patients

Obstructive sleep apnea (OSA) is a common disorder in which upper-airway obstruction during sleep results in cessation of breathing. OSA is associated with increased morbidity and mortality and impaired daytime functioning. Upper-body obesity is a risk factor for OSA, and it is well documented that weight loss has a notable ameliorative impact on the occurrence of OSA. Nasal continuous positive airway pressure (nCPAP) during sleep is the primary treatment for OSA, and is usually effective in relieving upper-airway obstruction. However, compliance with prolonged nCPAP use has been proven problematic. Upper-airway surgeries may be efficacious for the treatment of OSA in carefully selected patients, but often are not successful for obese patients with OSA. The concomitant use of nCPAP and behavioral weight loss therapy in obese patients with OSA may result in enhanced weight loss. In moderately obese patients, modest weight reduction may alleviate the need for long-term nCPAP therapy or upper-airway surgery. Severely obese patients usually require more substantial weight loss and may be candidates for behavioral therapy in combination with gastric surgery. The role of the dietitian in the treatment of OSA cannot be overemphasized and warrants further development and study.

Commentary

Antiretroviral therapy has significantly reduced morbidity and mortality in people living with HIV (PLWH). However, a direct consequence of higher survival is the development of ageing-related co-morbidities that have considerable potential to affect quality of life. Sleep disturbances in PLWH are a significant source of morbidity. A meta-analysis has estimated the prevalence of self-reported sleep disturbances in PLWH to be 58%, with commonly identified disturbances including insomnia, obstructive sleep apnoea and poor sleep quality. Not only do sleep disturbances impair daytime functioning, but chronic sleep disruption also associates with metabolic dysregulation and cardiometabolic disease. Therefore, an understanding of the pathogenesis of sleep disturbances in PLWH is important for reducing morbidity and improving quality of life. Several pathophysiological processes in HIV infection may cause sleep-wake dysregulation. In early infection stages, immunological changes such as expression of sleep-promoting cytokines could mediate sleep disturbances. Long term, chronic immune activation, in addition to side effects of antiretroviral therapy, may impact sleep homeostasis more severely, for example through increasing the risk of obstructive sleep apnoea. These sleep disturbances may further contribute to an inflammatory state, due to the bi-directional relationship between sleep and immunity. In summary, further elucidating the link between HIV, immune activation, and sleep is an underexplored avenue for minimising population morbidity and mortality.

Vital exhaustion and perception of sleep

Sleep complaints and unusual sleep durations have been found to increase the risk for coronary heart disease. One explanation states that insomnia and excess fatigue on final waking are predictive for myocardial infarction because they are part of a state of ‘vital exhaustion’. Sleep complaints and sleep durations, however, are usually assessed with retrospective self-report procedures. Such procedures must be interpreted with reserve because in insomniacs, a consistent disparity in the perception of habitual and current sleep has been observed. This caused us to question whether this phenomenon is present in exhausted males also. Two approaches were used. The first one consisted of a retrospective assessment of subjective sleep characteristics, the second one of self-monitoring these sleep characteristics during 21 days. In the second week, subjects slept in a laboratory. No disparity was found in how exhausted males perceive their habitual and current sleep. It appeared that sleep quality is worse and sleep duration is shorter in exhausted males. They also feel more sleepy and take longer naps during the day, indicating that their daytime functioning is impaired. Sleeping in a laboratory reduced time asleep and midsleep wake. Sleep quality, however, was essentially the same as at home. These findings made us conclude that it is not the intrusion of nocturnal wake times per se but more likely the impaired daytime functioning which is the reason for exhausted males to complain about their sleep.

Factors Impairing Daytime Performance in Patients With Sleep Apnea/Hypopnea Syndrome

Patients with sleep apnea/hypopnea syndrome commonly demonstrate impaired daytime performance. In a prospective study, 29 patients with sleep apnea/hypopnea syndrome were assessed polysomnographically to determine the relationship of cognitive performance and daytime sleepiness with sleep disruption, hypoxemia, and mood. Deterioration of cognitive performance correlated significantly with increasing severity of nocturnal breathing irregularity, magnitude of nocturnal hypoxemia, and extent of sleep disruption. Multiple regression analysis identified frequency of apneas plus hypopneas and of arousal and the extent of nocturnal hypoxemia as the variables most strongly associated with cognitive deficits. Anxiety and depression also contributed to this impairment. Objective daytime sleepiness was not significantly associated with nocturnal variables. This study showed that the frequency of breathing irregularities and the extent of both sleep disruption and nocturnal hypoxemia are important in determining daytime function in patients with sleep apnea/hypopnea syndrome. All of these factors should be considered when deciding which patients require treatment.

Subjective and Objective Performance in Patients with Persistent Insomnia

Abstract Patients with persistent insomnia generally complain about impaired daytime performance, memory lapses, etc., but it has been difficult to document these impairments empirically. One possibility is that insomnia patients are more likely to be dissatisfied with their actual performance, even when they perform as well as normals. In order to test this hypothesis, 20 insomniacs and 20 normal sleepers were compared both as to their objective performance and their subjectively perceived performance on a computerized test battery with four tasks: reaction time, two memory tasks, and finger tapping. As predicted, the results showed no differences between insomniacs and controls on objective performance, but revealed significant differences on subjective measures of performance: insomniacs rated significantly lower on performance expectancy, performance evaluation, results compared to others, and results compared to own real capacity. Insomniacs also rated significantly higher on state anxiety than the c...

Electroencephalographic Parameters in Assessing the Cognitive Function of Children with Epilepsy

Many biological and psychological possibilities have to be considered when attempting to explain cognitive dysfunction in the individual child with epilepsy. Electroencephalographic (EEG) information, which may be particularly relevant in some children, has mainly been studied in relation to the possible direct effects of seizure discharges on learning and behavior. Such discharges can be divided into transient, brief or prolonged. Prolonged seizure discharges includes nonconvulsive status epilepticus during wakefulness and status epilepticus during slow-wave sleep. In addition to the influence of seizure discharges, preliminary findings suggest that some children with epilepsy might have a subtle disorder of arousal mechanisms in sleep, possibly associated with impaired daytime performance.

Hypnotic drugs: Use and abuse

Hypnotic drugs have a number of pharmacologic properties which contribute to their safety and efficacy as well as to their abuse potential. Benzodiazepines are among the safest of all depressant compounds and do not lose their effectiveness as quickly as do nonbenzodiazepine drugs. They differ in their half-lives and duration of action. Short- and intermediate-acting benzodiazepines can cause rebound insomnia and rebound anxiety in certain patients but can aid in daytime alertness in others. Long-acting benzodiazepines can impair daytime performance and cause daytime sleepiness but can be useful in minimizing withdrawal effects. Selection of a proper hypnotic should depend on the clinical situation and the needs of the patient. Principles for proper use are discussed.