Heather M. Engleman

Compliance with CPAP therapy in patients with the sleep apnoea/hypopnoea syndrome.

BACKGROUND--Continuous positive airway pressure (CPAP) therapy is the treatment of choice for the sleep apnoea/hypopnoea syndrome. Compliance with this relatively obtrusive therapy has not been well studied. METHODS--Usage of CPAP was investigated in 54 patients with sleep apnoea/hypopnoea syndrome (median 36 (range 7-129) apnoeas + hypopnoeas/hour slept) over the first 1-3 months after starting CPAP therapy. In all cases CPAP usage was monitored by hidden time clocks that indicated for how long the machines were switched on--that is, the CPAP run time. In 32 patients the time at which the CPAP mask pressure was at the therapeutic level of CPAP pressure set for that patient--that is, the mask time--was also monitored. In all patients objective daytime sleepiness was assessed by multiple sleep latency before and after CPAP therapy. RESULTS--The mean (SE) nightly CPAP run time was 4.7 (0.4) hours. There was no correlation between run time and severity of the sleep apnoea/hypopnoea syndrome as assessed by apnoea + hypopnoea frequency or multiple sleep latency, and no correlation between CPAP usage and improvement in multiple sleep latency. Thirty two patients in whom mask time was recorded had therapeutic CPAP pressures for 89% (3%) of their CPAP run times. Patients who experienced side effects from CPAP used their CPAP machines significantly less than those who did not. CONCLUSIONS--Patients with sleep apnoea/hypopnoea syndrome used CPAP for less than five hours/night on average with no correlation between severity of sleep apnoea/hypopnoea syndrome and CPAP usage. Patients who complained of side effects used their CPAP therapy less. It is recommended that, as a minimum, CPAP run time should be regularly recorded in all patients receiving CPAP therapy.

Randomised placebo controlled trial of daytime function after continuous positive airway pressure (CPAP) therapy for the sleep apnoea/hypopnoea syndrome.

BACKGROUND Patients with the sleep apnoea/hypopnoea syndrome (SAHS) report improved sleepiness, cognitive function, and psychological well being after continuous positive airway pressure (CPAP) therapy, and it is for these daytime features that CPAP is usually given. However, few randomised or controlled studies exist on the effects of CPAP on daytime function. METHODS A prospective, randomised, single blind, placebo controlled, crossover trial of daytime function after CPAP was conducted in 23 patients with SAHS, all with ⩾15 apnoeas+hypopnoeas/hour and ⩾2 symptoms of SAHS. All patients spent four weeks on CPAP therapy and four weeks on oral placebo treatment, following randomisation to treatment order. With ethics committee approval, patients were told the placebo tablet might improve upper airway function. Average effective CPAP use was monitored using hidden time clocks. Assessments of objective and subjective sleepiness, symptoms, cognitive performance, and psychological well being were performed on the last day of each treatment and compared. RESULTS Objective sleepiness measured by sleep onset latency on the multiple sleep latency test improved with CPAP (mean difference from placebo +2.4 min, 95% CI 0.8 to 4.0; p<0.001) as did subjective sleepiness on the Epworth scale (mean difference –6, 95% CI –3 to –9; p = 0.001). Symptom total score also fell with CPAP (mean difference –1.6, 95% CI –2.2 to –1.0; p<0.001). No determinants of these changes with active treatment were identified, and no significant enhancements to cognitive function or psychosocial well being were found in this small sample. CONCLUSIONS These findings provide further evidence for clinically significant benefits to daytime function from CPAP.

Randomized Controlled Clinical Effectiveness Trial of Cognitive Behavior Therapy Compared With Treatment As Usual for Persistent Insomnia in Patients With Cancer

PURPOSE Persistent insomnia is a common complaint in cancer survivors, but is seldom satisfactorily addressed. The adaptation to cancer care of a validated, cost-effective intervention may offer a practicable solution. The aim of this study was to investigate the clinical effectiveness of protocol-driven cognitive behavior therapy (CBT) for insomnia, delivered by oncology nurses. PATIENTS AND METHODS Randomized, controlled, pragmatic, two-center trial of CBT versus treatment as usual (TAU) in 150 patients (103 females; mean age, 61 years.) who had completed active therapy for breast, prostate, colorectal, or gynecological cancer. The study conformed to CONSORT guidelines. Primary outcomes were sleep diary measures at baseline, post-treatment, and 6-month follow-up. Actigraphic sleep, health-related quality of life (QOL), psychopathology, and fatigue were secondary measures. CBT comprised five, small group sessions across consecutive weeks, after a manualized protocol. TAU represented normal clinical practice; the appropriate control for a clinical effectiveness study. RESULTS CBT was associated with mean reductions in wakefulness of 55 minutes per night compared with no change in TAU. These outcomes were sustained 6 months after treatment. Standardized relative effect sizes were large for complaints of difficulty initiating sleep, waking from sleep during the night, and for sleep efficiency (percentage of time in bed spent asleep). CBT was associated with moderate to large effect sizes for five of seven QOL outcomes, including significant reduction in daytime fatigue. There was no significant interaction effect between any of these outcomes and baseline demographic, clinical, or sleep characteristics. CONCLUSION CBT for insomnia may be both clinically effective and feasible to deliver in real world practice.

Daytime sleepiness, cognitive performance and mood after continuous positive airway pressure for the sleep apnoea/hypopnoea syndrome.

BACKGROUND--Patients with the sleep apnoea/hypopnoea syndrome often receive continuous positive airway pressure to improve their symptoms and daytime performance, yet objective evidence of the effect of this treatment on cognitive performance is lacking. METHODS--A prospective parallel group study was performed comparing the change in objective daytime sleepiness as assessed by multiple sleep latency, cognitive function, and mood in 21 patients (mean (SE) number of apnoeas and hypopnoeas/hour 57 (6)) who received continuous positive airway pressure for three months and 16 patients (49(6) apnoeas and hypopnoeas/hour) who received conservative treatment for a similar period. RESULTS--Both groups showed significant within group changes in cognitive function between baseline and three months, but when comparisons were made between groups the only significant difference was a greater improvement in multiple sleep latency with continuous positive airway pressure. However, the improvement in sleep latency with continuous positive airway pressure was relatively small (3.5 (0.5) to 5.6 (0.7) min). The group treated with continuous positive airway pressure was divided into those who complied well with treatment (> 4.5 hours/night) and those who did not. Those who complied well (n = 14) showed significant improvement in mean sleep latency and also in depression score compared with the controls but no greater improvement in cognitive function. CONCLUSION--This study confirms significant improvements in objective sleepiness and mood with continuous positive airway pressure, but shows no evidence of major improvements in cognitive function.

Sleep-disordered breathing after stroke: a randomised controlled trial of continuous positive airway pressure

Background: Sleep-disordered breathing (SDB) is common after stroke, but it is unclear whether it should be treated. Objective: To conduct a randomised controlled trial of continuous positive airway pressure (CPAP) after stroke. Methods: Patients with stroke with ⩾30 apnoeas and hypopnoeas per hour ((A+H)/h) with predominant obstructive sleep apnoea or hypopnoea were randomised to either CPAP treatment or conservative treatment for 8 weeks. Outcomes were measured blind to treatment allocation at 8 weeks and 6 months after the stroke. The primary outcome was physical function on the Nottingham Extended Activities of Daily Living Scale. Results: Of 658 patients with stroke screened, only 71 (10.7%) were eligible and consented to a sleep study 14–19 days after stroke. 66 patients completed the sleep study (21 women; mean age 72 years), 33 (50%) had ⩾30 (A+H)/h that were predominantly obstructive. 15 were randomised to CPAP treatment and 15 to conventional treatment. Despite intensive efforts, objective use of CPAP was poor, averaging 1.4 h a night. CPAP treatment resulted in no significant improvements (p>0.1) in the primary outcome or in neurological function or sleepiness, and in poorer health status on some measures. Conclusions: This trial showed no benefit from CPAP treatment, the relevance of the observed detrimental effects is questionable. Even in our highly selected patients with stroke, use of CPAP was poor. At present, CPAP treatment should be advocated for patients with stroke only if they have symptoms of SDB.

Morbidity in nocturnal asthma: sleep quality and daytime cognitive performance.

Most patients with asthma waken with nocturnal asthma from time to time. To assess morbidity in patients with nocturnal asthma nocturnal sleep quality, daytime sleepiness, and daytime cognitive performance were measured prospectively in 12 patients with nocturnal asthma (median age 43 years) and 12 age and intellect matched normal subjects. The median (range) percentage overnight fall in peak expiratory flow rate (PEF) was 22 (15 to 50) in the patients with nocturnal asthma and 4 (-4 to 7) in the normal subjects. The patients with asthma had poorer average scores for subjective sleep quality than the normal subjects (median paired difference 1.1 (95% confidence limits 0.1, 2.3)). Objective overnight sleep quality was also worse in the asthmatic patients, who spent more time awake at night (median difference 51 (95% CL 8.1, 74) minutes), had a longer sleep onset latency (12 (10, 30) minutes), and tended to have less stage 4 (deep) sleep (-33 (-58, 4) minutes). Daytime cognitive performance was worse in the patients with nocturnal asthma, who took a longer time to complete the trail making tests (median difference 62 (22, 75) seconds) and achieved a lower score on the paced serial addition tests (-10 (-24, -3)). Mean daytime sleep latency did not differ significantly between the two groups (2 (-3, 7) minutes). It is concluded that hospital outpatients with stable nocturnal asthma have impaired sleep quality and daytime cognitive performance even when having their usual maintenance asthma treatment.

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.

Neuropsychological function in obstructive sleep apnoea

Patients with obstructive sleep apnoea (OSA) experience neuropsychological deficits falling broadly into the four areas of daytime sleepiness, cognitive deficits, reduced driving competence and impaired psychosocial well-being. Case-control studies of daytime function in OSA patients generally indicate moderate to severe daytime sleepiness using polysomnographic or self-rating assessments. Cognitive performance on tests of attention and concentration ability, visuomotor and constructional skills, verbal fluency, planning and problem-solving, memory and executive function may be mildly to moderately impaired. These two symptoms may contribute to a road traffic accident rate in OSA between two and seven times higher than that of normals, and to the high prevalence of minor psychiatric morbidity, and reductions in functional and health status, among patients. The daytime impairments associated with OSA are improved by continuous positive airway pressure (CPAP) therapy, although a lack of complete normalization has been suggested for objective sleepiness and some areas of cognitive function. The severity of sleepiness and cognitive impairments show weak and moderate correlations with frequency of sleep-disordered breathing in clinical and epidemiological studies. Experimental and clinical evidence supports a role for nocturnal physiological events of OSA, arousals and hypoxaemia, in directly or indirectly producing neuropsychological deficits, particularly those of sleepiness and cognitive deterioration.

Microarousals in patients with sleep apnoea/hypopnoea syndrome

SUMMARY Upper airway obstructions during sleep cause recurrent brief awakenings or microarousals. Standard criteria exist for sleep and respiratory event scoring, however, there are different definitions currently used to score microarousals. We therefore compared three definitions of microarousal (ranging from 1.5‐3 s in duration) and one of awakening (> 15 s). We examined their occurrence at the termination of apnoeas and hypopnoeas and their correlation with daytime sleepiness in patients with sleep apnoea/hypopnoea syndrome (SAHS). Sixty‐three patients (aged 49, SD 10) had overnight polysomnography, multiple sleep latency tests (MSLT) and Epworth Sleepiness Scales (ESS). There were significantly more microarousals by any definition than there were awakenings (P<0.001) and there were more 1.5 s than 3 s microarousals (P<0.001). Significantly more apnoeas and hypopnoeas were terminated by 1.5 s microarousals (83% and 81%) than by 3 s microarousals (75%) (all P<0.001). Apnoea/hypopnoea index (AHI) correlated significantly with objective daytime sleepiness (p = ‐0.30, P<0.01). There were weakly significant relationships between all three microarousal definitions (‐0.24

Under reporting of sleepiness and driving impairment in patients with sleep apnoea/hypopnoea syndrome.

SUMMARY Under reporting of symptoms by patients with sleep apnoeal/hypopnoea syndrome (SAHS) has been reported anecdotally, but investigation of the prevalence or determinants of this is limited. To assess this, repeated ratings in 99 patients with sleep apnoea/hypopnoea syndrome of pre‐treatment Epworth sleepiness score, unintended napping, driving impairment and mood were obtained, first at presentation and then after treatment with continuous positive airway pressure (CPAP) therapy of median 22 (range 2‐70) weeks duration. Median Epworth score for pre‐treatment sleepiness rose from 12 (range 0‐24) initially to 14 (range 5‐24) retrospectively (P<0.0001). More patients initially under‐rated Epworth score (67%) than over‐rated (29%; P0.001). ‘False negative’ cases with an initially ‘normal’ (≤ 10) and retrospectively ‘sleepy’ (≥ 11) Epworth score comprised 24% of all patients and 62% of initially ‘normal’ scorers. Unintended napping behaviour also was rated as significantly more severe on retrospective assessment (P<0.001). Driving impairment due to sleepiness was initially reported by 23% of all drivers and retrospectively by 37% (P=0.01), with 25% of initial deniers retrospectively admitting compromised driving ability before continuous positive airway pressure. No polysomnographic predictors of symptom under reporting were found (P 0.1). These results suggest a high prevalence of symptom minimization before treatment in patients with sleep apnoea/hypopnoea syndrome.