OBJECTIVE:
To examine whether treatment of obstructive sleep apnea (OSA) with continuous positive airway pressure (CPAP) in patients with Alzheimer's disease (AD) would result in improved cognitive function.

Cognitive effects of treating obstructive sleep apnea in Alzheimer's disease: a randomized controlled study.

Sleep and Alzheimer's disease

The complexity of central breathing disturbances during sleep has become increasingly obvious. They present as central sleep apnoeas (CSAs) and hypopnoeas, periodic breathing with apnoeas, or irregular breathing in patients with cardiovascular, other internal or neurological disorders, and can emerge under positive airway pressure treatment or opioid use, or at high altitude. As yet, there is insufficient knowledge on the clinical features, pathophysiological background and consecutive algorithms for stepped-care treatment. Most recently, it has been discussed intensively if CSA in heart failure is a "marker" of disease severity or a "mediator" of disease progression, and if and which type of positive airway pressure therapy is indicated. In addition, disturbances of respiratory drive or the translation of central impulses may result in hypoventilation, associated with cerebral or neuromuscular diseases, or severe diseases of lung or thorax. These statements report the results of an European Respiratory Society Task Force addressing actual diagnostic and therapeutic standards. The statements are based on a systematic review of the literature and a systematic two-step decision process. Although the Task Force does not make recommendations, it describes its current practice of treatment of CSA in heart failure and hypoventilation.

https://erj.ersjournals.com/content/erj/49/1/1600959.full.pdf

Definition, discrimination, diagnosis and treatment of central breathing disturbances during sleep

Objectives To determine the clinical effectiveness, safety and cost-effectiveness of continuous positive airway pressure (CPAP) devices for the treatment of obstructive apnoea-hypopnoea syndrome (OSAHS), compared with the best supportive care, placebo and dental devices. Data sources The main search was of fifteen electronic databases, including MEDLINE, EMBASE and the Cochrane Library, up to November 2006. Review methods Randomised controlled trials (RCTs) comparing CPAP with best supportive/usual care, placebo, and dental devices in adults with a diagnosis of OSAHS were included. The primary outcomes of interest were subjective daytime sleepiness assessed by the Epworth Sleepiness Scale (ESS) and objective sleepiness assessed by the Maintenance of Wakefulness Test (MWT) and the Multiple Sleep Latency Test (MSLT). A new economic model was developed to assess incremental cost per quality-adjusted life-year (QALY). The cost-effectiveness of CPAP was compared with that of the use of dental devices and conservative management. The costs and QALYs were compared over a lifetime time horizon. Effectiveness was based on the RCT evidence on sleepiness symptoms (ESS), which was 'mapped' to utilities using individual patient data from a subset of studies. Utilities were expressed on the basis of generic HRQoL instruments [the EQ-5D (EuroQoL-5 Dimensions) in the base-case analysis]. The base-case analysis focused on a male aged 50. A series of subgroup and scenario analyses were also undertaken. Results The searches yielded 6325 citations, from which 48 relevant clinical effectiveness studies were identified, 29 of these providing data on daytime sleepiness. The majority of the included RCTs did not report using an adequate method of allocation concealment or use an intention-to-treat analysis. Only the studies using a sham CPAP comparator were double blinded. There was a statistically significant benefit with CPAP compared with control (placebo and conservative treatment/usual care) on the ESS [mean difference (MD) -2.7 points, 95% CI -3.45 to -1.96]. However, there was statistical heterogeneity, which was reduced when trials were subgrouped by severity of disease. There was also a significant benefit with CPAP compared with usual care on the MWT. There was a non-statistically significant difference between CPAP and dental devices (six trials) in the impact on daytime sleepiness (ESS) among a population with moderate symptom severity at baseline (MD -0.9, 95% CI -2.1 to 0.4). A review of five studies evaluating the cost-effectiveness of CPAP was undertaken. All existing cost-effectiveness studies had limitations; therefore a new economic model was developed, based on which it was found that, on average, CPAP was associated with higher costs and benefits than dental devices or conservative management. The incremental cost per QALY gained of CPAP was below 20,000 pounds in the base-case analysis and most alternative scenarios. There was a high probability of CPAP being more cost-effective than dental devices and conservative management for a cost-effectiveness threshold of 20,000 pounds per QALY gained. Conclusions CPAP is an effective and cost-effective treatment for OSAHS compared with conservative/usual care and placebo in populations with moderate to severe daytime sleepiness, and there may be benefits when the disease is mild. Dental devices may be a treatment option in moderate disease but some uncertainty remains. Further research would be potentially valuable, particularly investigation of the effectiveness of CPAP for populations with mild sleepiness and further trials comparing CPAP with dental devices.

Continuous positive airway pressure devices for the treatment of obstructive sleep apnoea-hypopnoea syndrome: a systematic review and economic analysis

Introduction:Obstructive sleep apnea (OSA) is common among patients with Alzheimer's disease (AD). Untreated OSA exacerbates the cognitive and functional deficits. Continuous positive airway pressu...

Sustained Use of CPAP Slows Deterioration of Cognition, Sleep, and Mood in Patients with Alzheimer's Disease and Obstructive Sleep Apnea: A Preliminary Study

OBJECTIVES: Studies have reported that 33% to 70% of patients with Alzheimer's disease (AD) have sleep-disordered breathing (SDB). Continuous positive airway pressure (CPAP) treatment has been shown to reduce daytime sleepiness and improve health-related quality of life in nondemented older people with SDB. The effect of therapeutic CPAP treatment on daytime sleepiness in patients with mild-moderate AD with SDB was assessed.



DESIGN: Randomized, double-blind, placebo-controlled trial.



SETTING: Patients' home and the University of California San Diego, General Clinical Research Center, J. Christian Gillin Laboratory of Sleep and Chronobiology.



PARTICIPANTS: Thirty-nine community-dwelling elderly patients with mild-moderate probable AD with SDB.



INTERVENTION: Patients were randomly assigned to receive 6 weeks of therapeutic CPAP or 3 weeks of sham CPAP followed by 3 weeks of therapeutic CPAP.



MEASUREMENTS: Epworth Sleepiness Scale (ESS) was administered at baseline, 3 weeks, and 6 weeks. Changes in daytime sleepiness in subjects who received optimal therapeutic CPAP were compared with changes in the sham CPAP group.



RESULTS: Within the therapeutic CPAP group, ESS scores were reduced from 8.89 during baseline to 6.56 after 3 weeks of treatment (P=.04) and to 5.53 after 6 weeks of treatment (P=.004). In the sham CPAP group, there was no significant difference after 3 weeks of sham CPAP but a significant decrease from 7.68 to 6.47 (P=.01) after 3 weeks of therapeutic CPAP.



CONCLUSION: These data provide evidence of the effectiveness of CPAP in reducing subjective daytime sleepiness in patients with AD with SDB.

Continuous Positive Airway Pressure Reduces Subjective Daytime Sleepiness in Patients with Mild to Moderate Alzheimer's Disease with Sleep Disordered Breathing

Mei S. Chong

Papers

Continuous Positive Airway Pressure Reduces Subjective Daytime Sleepiness in Patients with Mild to Moderate Alzheimer's Disease with Sleep Disordered Breathing