Tirzepatide Combined With Continuous Positive Airway Pressure Treatment in Obstructive Sleep Apnoea Syndrome With Comorbid Obesity: Effects on Weight, Daytime Sleepiness, and Cognitive Performance.

Update on Obstructive Sleep Apnea: Implications for Neuropsychiatry.

Obstructive sleep apnea (OSA) is a sleep disorder with sleep fragmentation, which decreased daytime alertness and induced neurocognitive dysfucntion. The standard treatment of continuous positive airway pressure (CPAP) treatment on OSA patients has been demonstrated to improve daytime sleepiness but the effects on cognitive functions were poorly understood. Our study took psychomotor vigilance task, flanker task, stroop task and two questionnaires (Pittsburgh sleep quality index (PSQI) and Epworth sleepiness scale (ESS)) to measure cognitive function and daytime sleepiness in OSA patients before, after 3-week, and after 3-month standard CPAP treatment. Forty-five OSA patients show significant improvement in executive function with flanker task and Stroop task after 3-weeks and 3-months CPAP treatment as well as improvement of PSQI and ESS. OSA patients improved accuracy rate (AR) as well as decreased omission rate (OR), error rate (ER) and post-error error rate in flanker task after 3 weeks CPAP treatment. Further, three-month CPAP treatment improved incongruent reaction time (RT) in flanker task. The same group improved AR and decreased mean RT, OR, ER, as well as improved congruent and incongruent AR and shorten RT after 3 weeks treatment. Congruent accuracy rate can significant improved after 3 months CPAP used. However, the OSA patients show no significant improvement in vigilance task after 3-week and 3-mpnth CPAP treatment. In conclusion, our study demonstrates that short term and long term CPAP treatment could improve both executive function (improved accuracy rate and shortened reaction time) and sleep quality in OSA patients.

Expansion of the ageing population has led to questions about the rationalisation of health-care support and the cost-effectiveness ratio of all treatment approaches for elderly patients. Sleep-related breathing disorders are highly prevalent after age 65 years,1Sforza E Gauthier M Crawford-Achour E et al.A 3-year longitudinal study of sleep disordered breathing in the elderly.Eur Respir J. 2012; 40: 665-672Crossref PubMed Scopus (22) Google Scholar and their treatment is a major reason for the increase in health-care spending. Obstructive sleep apnoea (OSA) syndrome is a well established risk factor for cardiovascular diseases in adults, but the deleterious effect of OSA syndrome in elderly people remains controversial,2Lavie P Lavie L Unexpected survival advantage in elderly people with moderate sleep apnoea.J Sleep Res. 2009; 18: 397-403Crossref PubMed Scopus (136) Google Scholar and some authors have discussed the concept of so-called preconditioning with chronic intermittent hypoxia, meaning elderly apnoeic patients could have less chance of myocardial infarction.3Rosenzweig I Kempton MJ Crum WR et al.Hippocampal hypertrophy and sleep apnea: a role for the ischemic preconditioning?.PLoS One. 2013; 8: e83173Crossref PubMed Scopus (46) Google Scholar The unknown benefits routinely offered by the treatment of OSA syndrome in elderly patients should be taken into account by public authorities when planning resource allocation. However, the main symptom associated with sleep apnoea, diurnal sleepiness, seems to be costly and dangerous in this population4Gooneratne NS Richards KC Joffe M et al.Sleep disordered breathing with excessive daytime sleepiness is a risk factor for mortality in older adults.Sleep. 2011; 34: 435-442PubMed Google Scholar and seems to be a valid target for the efficacy of treatment of OSA syndrome in older people. In the PREDICT study published in The Lancet Respiratory Medicine, Alison McMillan and colleagues5McMillan A Bratton D Faria R et al.Continuous positive airway pressure in older people with obstructive sleep apnoea syndrome (PREDICT): a 12-month, multicentre, randomised trial.Lancet Respir Med. 2014; (published online Aug 27.)http://dx.doi.org/10.1016/S2213-2600(14)70172-9Google Scholar show in a multicentre, randomised, two-parallel-group study of continuous positive airway pressure (CPAP) that this treatment significantly reduced daytime sleepiness in patients aged 65 years or older at 3-month and 1-year follow-up visits. The quality of work done by the authors should be emphasised. The magnitude of improvement is quite similar to that noted in younger adults, and this amplitude is well correlated with the average night duration use of CPAP.6Marshall NS Barnes M Travier N et al.Continuous positive airway pressure reduces daytime sleepiness in mild to moderate obstructive sleep apnoea: a meta-analysis.Thorax. 2006; 61: 430-434Crossref PubMed Scopus (165) Google Scholar The short median duration of CPAP usage in the PREDICT study (1 h 52 min per night at 3 months and 2 h 22 min per night at 12 months) suggests a greater efficiency of CPAP for patients with longer nightly CPAP use. A minimum duration of 5 h of daily use for patients should be insisted upon if CPAP is to have a substantial effect on neurocognitive function.7Antic NA Catcheside P Buchan C et al.The effect of CPAP in normalizing daytime sleepiness, quality of life, and neurocognitive function in patients with moderate to severe OSA.Sleep. 2011; 34: 111-119Crossref PubMed Google Scholar The authors did not attempt to explain the important question of the beneficial role of CPAP on cardiovascular morbidity and mortality in patients aged 65 years or older. This treatment approach leads to a marginal reduction in health costs. During 1-year follow-up, CPAP does not seem to improve mood, cognitive function, or incidence of accidents. We should emphasise here that the study was not originally designed to address these issues, and thus, firm conclusions could not be derived from these secondary endpoint analyses. In our opinion, the decrease in plasma LDL cholesterol is difficult to explain by the nocturnal CPAP alone.8Roche F Sforza E Pichot V et al.Obstructive sleep apnoea/hypopnea influences high-density lipoprotein cholesterol in the elderly.Sleep Med. 2009; 10: 882-886Summary Full Text Full Text PDF PubMed Scopus (59) Google Scholar Somewhat surprisingly, the lower blood pressure noted in the group who received best supporting care can only encourage us to heavily emphasise advice on lifestyle (reducing physical inactivity, reducing salt intake, and improving medication adherence) when patients are seen in our sleep medicine clinics.9Mendelson M Tamisier R Laplaud D et al.Low physical activity is a determinant for elevated blood pressure in high cardiovascular risk obstructive sleep apnea.Respir Care. 2014; 59: 1218-1227Crossref Scopus (16) Google Scholar The reported decrease of 3–4 mm Hg in blood pressure could be very profitable in terms of health costs at the 10-year follow-up point. Several criticisms can be made of this study. First is the use of the Epworth sleepiness scale to characterise the extent of daytime sleepiness; this questionnaire is sometimes not suitable for elderly patients because most are not able to answer all of the Epworth scale score items, thus this scale might underestimate sleepiness severity in older patients.10Onen F Moreau T Gooneratne NS Petit C Falissard B Onen SH Limits of the Epworth Sleepiness Scale in older adults.Sleep Breath. 2013; 17: 343-350Crossref PubMed Scopus (60) Google Scholar However, significant and consistent improvements in the Oxford Sleep Resistance test reported in the CPAP group confirm an objective improvement in daytime sleepiness from use of CPAP. Additionally, a detailed comparative analysis of the macroarchitecture and microarchitecture of sleep in the two groups of patients is absent. In fact, sleep apnoea syndrome in elderly people is often entangled with other sleep diseases, and it would have been interesting to compare the improvement of the effectiveness and continuity of sleep in both groups. Finally, daytime sleepiness is usually present less often (and if present, is less severe) in elderly patients with OSA syndrome, and elderly patients can cope better with sleepiness symptoms because they are often not in full-time work. Older apnoeic patients screened and recruited in this study were far from representative of the whole panel of older apnoeic patients seen in routine clinical practice. Many elderly apnoeic patients have no daytime sleepiness and consult for other symptoms—eg, nocturia, severe snoring, waking with feelings of choking, or minor memory complaints—or OSA is discovered by chance after onset of stroke or heart attack. It is difficult to determine the benefit of CPAP in the non-sleepy elderly apnoeic patients complaining about non-specific symptoms associated with unrefreshing sleep. In the study, the number of women is low, and thus the underrepresentation of women reduces the generalisation of the results obtained in men. We know that daytime sleepiness, according to an equivalent severity of apnoea or hypopnea, is often less severe in women than in men.1Sforza E Gauthier M Crawford-Achour E et al.A 3-year longitudinal study of sleep disordered breathing in the elderly.Eur Respir J. 2012; 40: 665-672Crossref PubMed Scopus (22) Google Scholar This difference in clinical presentation is important to consider in the detection and treatment of all apnoeic patients. The quality of the work in this study is remarkable and encourages continued high-quality controlled clinical trials in the specialty of sleep-related breathing disorders in elderly people; a disorder that can affect a third of patients aged 68 years or older and that might significantly accelerate cognitive decline in undiagnosed and untreated patients. We declare no competing interests. Continuous positive airway pressure in older people with obstructive sleep apnoea syndrome (PREDICT): a 12-month, multicentre, randomised trialIn older people with OSA syndrome, CPAP reduces sleepiness and is marginally more cost effective over 12 months than is BSC alone. On the basis of these results, we recommend that CPAP treatment should be offered routinely to older patients with OSA syndrome. Full-Text PDF Open Access

Obstructive sleep apnea syndrome (OSAS) is associated with impairment of cognitive function, and improvement is often noted with treatment. Golf is a sport that requires a range of cognitive skills. We evaluated the impact of nasal positive airway pressure (PAP) therapy on the handicap index (HI) of golfers with OSAS. Golfers underwent a nocturnal polysomnogram (NPSG) to determine whether they had significant OSAS (respiratory disturbance index > 15). Twelve subjects with a positive NPSG were treated with PAP. HI, an Epworth Sleepiness Scale (ESS), and sleep questionnaire (SQ) were submitted upon study entry. After 20 rounds of golf on PAP treatment, the HI was recalculated, and the questionnaires were repeated. A matched control group composed of non-OSAS subjects was studied to assess the impact of the study construct on HI, ESS, and SQ. Statistical comparisons between pre- and post-PAP treatment were calculated. The control subjects demonstrated no significant change in HI, ESS, or SQ during this study, while the OSAS group demonstrated a significant drop in average HI (11.3%, p = 0.01), ESS, (p = 0.01), and SQ (p = 0.003). Among the more skilled golfers (defined as HI ≤ 12), the average HI dropped by an even greater degree (31.5%). Average utilization of PAP was 91.4% based on data card reporting. Treatment of OSAS with PAP enhanced performance in golfers with this condition. Treatment adherence was unusually high in this study. Non-medical performance improvement may be a strong motivator for selected subjects with OSAS to seek treatment and maximize adherence.

Exercise capacity is impaired in obstructive sleep apnea (OSA). There are conflicting reports on the effect of continuous positive airway pressure (CPAP) on maximal exercise capacity. The objective of this review was to determine if there is a change in exercise capacity and anaerobic threshold following CPAP treatment in OSA patients. We conducted a systematic review and meta-analyses to summarize the changes in peak rate of oxygen uptake (V̇O₂ peak) or maximum rate of oxygen uptake (V̇O2 max) and anaerobic threshold (AT) during cardiopulmonary exercise testing following CPAP intervention in patients with OSA. A systematic literature review was conducted to identify published literature on markers of V̇O₂ peak, V̇O₂ max, and AT pre- vs post-CPAP using a web-based literature search of PubMed/MEDLINE, Embase, CINAHL, and Cochrane review (CENTRAL) databases. Two independent reviewers screened the articles for data extraction and analysis. The total search of all the databases returned 470 relevant citations. Following application of eligibility criteria, 6 studies were included in the final meta-analysis for V̇O₂ peak, 2 studies for V̇O₂ max, and five studies for AT. The meta-analysis showed a mean net difference in V̇O₂ peak between pre- and post-CPAP of 2.69 mL·kg-1·min-1, P = .02, favoring treatment with CPAP. There was no difference in V̇O₂ max or AT with CPAP treatment (mean net difference 0.66 mL·kg-1·min-1 [P = .78] and -144.98 mL·min-1 [P = .20] respectively). There is a paucity of high-quality studies investigating the effect of CPAP on exercise capacity. Our meta-analysis shows that V̇O₂ peak increases following CPAP treatment in patients with OSA, but we did not observe any change in V̇O₂ max or AT. Our findings should be considered preliminary and we recommend further randomized controlled trials to confirm our findings and to clarify the peak and maximum rates of oxygen uptake adaptations with CPAP therapy.

The Lung Centre, Vancouver, British Columbia Correspondence: Dr John A Fleetham, The Lung Centre, 7th Floor, 2775 Laurel Street, Vancouver, British Columbia V5Z 1M9. Telephone 604-875-5653, fax 604-875-5587, e-mail john.fleetham@vch.ca In the current issue of the Canadian Respiratory Journal, Rotenberg et al (1) (pages 170-174) report data from a crosssectional survey sent to otolaryngologists, respirologists and family physicians in Ontario, to characterize wait times for obstructive sleep apnea (OSA) care. The major finding was that patients with suspected OSA in Ontario waited a mean of 11.6 months to initiate continuous positive airway pressure (CPAP) treatment and 16.2 months to initiate surgical therapy. This is much longer than the wait time in the Canadian Thoracic Society (CTS) guidelines, which recommend a maximum wait time of two to four weeks for urgent patients with comorbid disease or daytime sleepiness and a critical safety occupation, and six months for all patients with suspected OSA (2,3). Excessive diagnostic wait times frequently lead to inappropriate or incorrect therapy. Wait times for the diagnosis of sleep apnea in Canada have not improved much since Flemons et al (4) reviewed wait times for the diagnosis of OSA in five countries, including Canada, 16 years previously. To paraphrase what Pack (5) wrote in an associated editorial: “It seems inconceivable that we should tell a patient the following: You are highly likely to have severe sleep apnea, a disorder associated with an increased risk of car crashes, high blood pressure, and probably heart attack and stroke. We have an effective treatment for this disorder. We will arrange a study for you in 11.6 months’ time to assess this”. The even longer wait time for surgical treatment of OSA reported by Rotenberg et al also merits comment. The role of corrective upper airway surgery in the treatment of OSA is controversial. The current CTS guidelines conclude that laser-assisted uvulopalatoplasty is not recommended for the treatment of OSA, but that uvulopalatopharyngoplasty may be considered in selected patients with OSA who have failed CPAP and/or oral appliance therapy. The delay in the diagnosis and treatment of OSA in Ontario needs to be put in the context of the rest of Canada, where the diagnosis and treatment of sleep apnea is provided in a very different manner. Ontario has the highest number of sleep laboratories in Canada and most other parts of the world apart from the United States (4). Moreover, Ontario is one of the few provinces, along with Manitoba and Saskatchewan, in which the provincial medical plan funds CPAP treatment. The majority of centres in Canada outside of Ontario use ambulatory sleep monitoring – in addition to polysomnography – to diagnose OSA. After OSA has been diagnosed, there is no additional delay in the provision of CPAP therapy because this is funded by the patient and does not require approval by a funding agency. The majority of respondents to the survey in the article by Rotenberg et al (1) identified ‘not enough sleep laboratories’ as the reason for long wait times. Many would argue that more sleep laboratories are not what is required – what is necessary is a more appropriate diagnostic strategy that uses clinical prediction equations and ambulatory sleep monitoring (6) in conjunction with polysomnography for patients with comorbid disease or who fail to improve with CPAP treatment. Furthermore, if resources for the management of OSA are to be rationed, a higher priority should be given to treatment than to diagnosis. Patients with OSA use health care services at approximately twice the rate of control subjects for up to 10 years before the diagnosis of OSA (7). CPAP treatment has an incremental cost-effectiveness ratio of $2,618 per quality-adjusted life year over no treatment (8). A ratio of less than $10,000 per qualityadjusted life year is generally considered to be extremely cost effective. While CPAP treatment for OSA is funded in many other countries including the United Kingdom (9) and the United States (10), it is not funded in the majority of Canadian provinces. In 2008, The Lung Association and the CTS jointly recommended funding of CPAP treatment under all provincial and federal health insurance plans for adults and children appropriately diagnosed with OSA; however, little progress has been made over the past two years. It is now time to end the postal code differences that currently exist in Canada with regard to access to the diagnosis and treatment of OSA. editorial

Recent studies report a link between obstructive sleep apnea (OSA) syndrome, low vitamin D levels, and high parathyroid hormone (PTH) concentrations. The aim of the current study is to evaluate the effect of 7-night continuous positive airway pressure (CPAP) therapy on serum vitamin D, PTH, and calcium levels in patients with severe OSA syndrome. Patients with severe OSA were enrolled into the study and compared to control subjects. Patients with OSA underwent CPAP therapy for 7 nights and were consequently divided into responders (OSA-R, mean residual AHI < 5/h) and nonresponders (OSA-nR, mean residual AHI > 5/h). Serum vitamin D, PTH, and calcium levels were measured at baseline in patients with severe OSA (apnea-hypopnea index > 30/h) and control subjects. Patients with OSA underwent a final morning blood sample after 7-night CPAP therapy. We enrolled 90 patients with OSA into the study (65 OSA-R and 25 OSA-nR) compared to 32 control subjects. At baseline, lower vitamin D and higher PTH levels were detected in the OSA group compared to controls. After 7-night CPAP therapy, male OSA-R patients showed a significant increase in vitamin D levels. Conversely, female OSA-R patients did not show the same increase in vitamin D levels. It was also observed that OSA-nR subjects did not show modifications of serum markers after nCPAP-therapy. The study demonstrates that short-term nCPAP treatment is able to promote the recovery of vitamin D homeostasis in male patients with OSA. The mediation of sexual hormones in regulating vitamin D is a possible explanation of the lack of recovery of vitamin D homeostasis in female patients with OSA as it often affects postmenopausal women.

Obstructive sleep apnea (OSA) is now widely seen as a major public health issue with many widespread societal consequences. In addition to an increased stroke risk, OSA leads to neurocognitive alterations. In two recent uncontrolled studies, OSA has been associated with gait impairments, which seemed to be improved after 8 weeks of continuous positive airway pressure (CPAP) treatment. The present controlled study tests the hypothesis that CPAP treatment will improve gait control in severe OSA patients. Prospective controlled study. 12 OSA (age=57.2±8.9 years, BMI=27.4±3.1 kg.m −2 , AHI=46.3±11.7, Epworth sleepiness scale=10±5) and 10 healthy matched subjects were included. Gait spatio-temporal parameters were recorded. Primary study endpoint, stride time variability (STV), a clinical marker of gait control linked with cognitive performance and cerebral integrity was calculated. The role of cognition in gait and postural control was assessed using a dual-task paradigm. Assessments were performed before and after 8 weeks of CPAP treatment. Before CPAP treatment, higher STV (3.1±1.1% vs 2.1±0.5%, p=0.02) and higher mean surface of center of pressure under single task condition (131.2±79.8mm 2 vs 66.9±21.9mm 2 , p=0.02) were measured in OSAS patients compared to controls. After CPAP treatment, STV was improved (2.4±0.5%, p=0.005) and no longer different compared to controls (p=0.32). Cognitive performance of OSA patients under dual task was impaired at baseline and improved under CPAP. CPAP treatment improve gait control of severe non-obese OSA patients suggesting morphological and functional cerebral improvements.

To explore the association between serum inflammation levels and cognitive function in patients with obstructive sleep apnea-hypopnea syndromes (OSAHS) and evaluate the effects of continuous positive airway pressure treatment (CPAP) on serum inflammation levels and cognitive function. A total of 139 eligible patients were monitored by overnight polysomnography (PSG) at Sleep Center, Second Affiliated Hospital, Soochow University from June 2011 to April 2013. Based on the results of apnea-hypopnea index (AHI), they were divided into 4 groups of primary snoring (n = 18), mild OSAHS(n = 23), moderate OSAHS (n = 29) and severe OSAHS (n = 69). The questionnaires of Montreal Cognitive Assessment (MoCA), Mini-Mental State Examination (MMSE) and Epworth Sleepiness Scale (ESS) were administered to assess cognitive function and daytime sleepiness. The serum levels of high-sensitivity C-reactive protein (Hs-CRP), leptin and tumor necrosis factor alpha (TNF-α) were detected to evaluate systemic inflammation. The questionnaire scores, serum levels of Hs-CRP, leptin and TNF-α and PSG parameters were compared among 4 groups. Thirty-three patients in severe OSAHS group (treatment group) with good adherence were evaluated at baseline and after long-time CPAP treatment. Compared to primary snoring group, the serum Hs-CRP ((1.77 ± 1.19) vs (0.92 ± 0.82) mg/L), leptin ((15.21 ± 13.26) vs (6.35 ± 4.51) mmol/L) and TNF-α ((21.04 ± 7.78) vs (10.30 ± 5.23) pmol/L) levels increased significantly in severe OSAHS group (P < 0.05). After adjusting for body mass index (BMI), age and education years, MoCA scores showed negative correlations with serum TNF-α, AHI, oxygen reduction index (ODI) and TS90% (r = -0.266, -0.236, -0.201, -0.18 respectively, all P < 0.05) and positive correlations with minimum oxygen saturation (LSaO(2)) (r = 0.224, P < 0.05). The evaluations of MoCA subdomains further revealed selective reductions in visual space, executive function, attention and delayed memory function. The treatment group with good adherence to > 6-month continuous positive airway pressure (CPAP) treatment and after CPAP treatment, the serum levels of Hs-CRP, TNF-α and leptin improved markedly ((1.20 ± 0.88) vs (2.03 ± 1.58) mg/L, (14.12 ± 4.34) vs (22.74 ± 6.72) pmol/L and (7.37 ± 5.30) vs (13.69 ± 7.17) mmol/L respectively). The scores of MoCA and ESS also improved (27.79 ± 1.69 vs 24.76 ± 2.57, 4.33 ± 3.14 vs 12.61 ± 5.80 respectively) (all P < 0.01). The score of all MoCA subdomains improved after treatment. Cognitive dysfunction and inflammatory reaction are common in OSAHS patients. MoCA scores are correlated significantly with serum level of TNF-α and nocturnal intermittent hypoxia. Systemic inflammation may play an important role in cognitive dysfunction of OSAHS patients. And long-time CPAP treatment can improve systemic inflammatory response and cognitive impairment.

<h3>Objective</h3> Literature proposed the clinical and electrophysiological evidence of optic nerve damage in obstructive sleep apnea (OSA) patients. The aim of this study is to evaluate in patients affected by OSA the effect of continuous positive airway pressure (CPAP) treatment on the functional integrity of the visual system evaluated by means of visual evoked potentials (VEP). <h3>Methods</h3> We performed the electrophysiological study of visual system in a population of 20 severe OSA patients at baseline and after 1-year of CPAP treatments. We divided OSA patients in two subgroups on the basis of the compliance at the CPAP therapy, measured by analyzing the software ventilator report. To be included in the study, OSA patients should not have visual impairment and systemic disorders with known influence on visual system. VEP were elicited by a reversal pattern generated on a television monitor at low (55′) and high (159) spatial frequencies stimulation. <h3>Results</h3> Ten patients show a good compliance at CPAP therapy (OSA-CPAP+) and 10 patients present an insufficient compliance at CPAP treatment (OSA-CPAP-). We documented the significant amelioration of latency and amplitude of VEP components in OSA-CPAP+ compared to OSA-CPAP-. <h3>Discussion</h3> Taking into account that OSA patients are affected by VEP alterations as documented by lower amplitude and longer latency of the P100 component, this study documented that CPAP treatment significantly ameliorate VEP in OSA patients who show good compliance at CPAP treatment with respect to OSA patients who did not adequately treat sleep apneas. Therefore, CPAP treatment may restore the altered electrophysiological findings present in OSA patients if appropriately performed.

A ten-year retrospective analysis of the clinical features and survival of 60 Saudi children with systemic lupus erythematosus (SLE) was made. All the patients fulfilled the 1982 American College of Rheumatologyâs revised criteria for SLE and had had the disease at or before the age of 16 years. The female to male ratio was 5:1, the mean age of onset was 12.1 years (range 1.6-16 years), and the mean duration of follow-up was 4.7 years (range 2.2-11). Thirty-eight patients (63%) were diagnosed correctly before referral to KFSH&RC or KKUH. The mode of presentation was as follows: 55 patients had musculoskeletal involvement (91.6%), 49 patients had skin involvement (81.6%), 40 patients had hematological abnormalities (66.6%), 39 patients had renal disease (65%), 10 patients had pulmonary involvement (16%), 23 patients had cardiovascular disease (38%) and 18 patients had central nervous system involvement. During the study period four patients died (6.6%)âtwo of renal failure, one from meningitis and one from severe sepsis. This is the largest collection of childhood systemic lupus erythematosus from the Middle East and it shows that SLE is more common in Saudis than was hitherto believed, and that it has a high rate of organ involvement.

Previous studies demonstrated that there was abnormal functional connectivity (FC) in the amygdala subregions in obstructive sleep apnea (OSA), which was associated with cognitive function. However, it is not clear whether these abnormalities can be improved after continuous positive airway pressure (CPAP) treatment. Therefore, the aim of this research was to investigate the changes in FC of amygdala subregions with other brain regions after 6 months of CPAP treatment (post-CPAP) in patients with OSA. Fifteen OSA patients underwent Magnetic Resonance Imaging prior to CPAP treatment (pre-CPAP) and following CPAP treatment. The amygdala was divided into six subregions, including bilateral dorsal amygdala (DA), medial amygdala (MA) and ventral amygdala (VA). The FC was calculated by using the amygdala subregions as seeds. A paired sample T-test was employed to assess alterations in the amygdala subregions FC of pre-CPAP and post-CPAP OSA patients, and correlation analysis was then conducted to evaluate the association between the changed FC and clinical assessment. Compared to pre-CPAP OSA patients, post-CPAP OSA patients displayed an enhanced FC between the left DA and the right posterior cingulate cortex (PCC), whereas the FC between the left MA and the right postcentral gyrus, and between the right MA and the left middle frontal gyrus, decreased. Moreover, significant correlation between the FC value of left DA-right PCC and Hamilton Anxiety Inventory scores was found in pre-CPAP OSA patients. Altered FC between the amygdala subregions and other brain regions in OSA patients induced by CPAP treatment was related to cognitive, emotional, and sensorimotor function. Our study found altered FC between amygdala subregions and cognitive and motor-related brain regions in post-CPAP OSA patients, providing potential neuroimaging indicators for CPAP treatment.

Background: The mechanisms underlying cognitive impairment in obstructive sleep apnea syndrome (OSAS) remain incompletely understood. In particular, the relative contribution of daytime sleepiness versus the direct effects of hypoxia on the brain requires clarification. Objectives: This study aims to explore the association between verbal memory and problem-solving abilities, OSAS severity, self-reported daytime sleepiness, and neurofilament light chain (NfL) serum concentration, as marker of neuroaxonal injury possibly related to chronic hypoxia. Methods: In this cross-sectional study, cognitive performance was assessed in 72 patients with mild to severe OSAS using the Selective Reminding Test (SRT) and the Tower of London (ToL). The apnea-hypopnea index (AHI), the Epworth Sleepiness Scale (ESS) and serum NfL concentrations were collected. Hierarchical multiple linear regression analyses adjusting for age, years of education, body mass index, and duration of continuous positive airway pressure (CPAP) treatment, were conducted for each cognitive outcome. Results. Neither AHI, ESS scores nor serum NfL concentrations were significantly associated with verbal memory or problem-solving performance. Higher age and lower education were significant predictors of lower verbal memory indices, whereas longer CPAP treatment duration was positively correlated with verbal memory performance and problem-solving speed. Conclusions: In this sample, cognitive performance was more strongly related to demographic factors and CPAP exposure compared to disease severity, subjective sleepiness, or peripheral markers of neuroaxonal injury. These findings suggest that AHI, subjective measures of sleepiness and NfL may inadequately capture neurocognitive vulnerability in OSAS. Moreover, they underscore the imperative for longitudinal and larger studies to clarify mechanisms linking OSAS and cognitive impairments.

In OSAS patients CPAP therapy decreases cardiovascular morbidity and mortality. Homocysteine and leptin may play a role in development of ischaemic heart disease (IHD) in patients with OSAS. The aim of the study was to assess the influence of 3 month CPAP therapy on cardiovascular risk factors in patients with OSAS without IHD (pure OSAS) and with OSAS and IHD. Therapy with CPAP was started in 42 OSAS without IHD (pure OSAS) and 23 OSAS and IHD patients. Plasma concentration of homocysteine, serum concentration of leptin, C-reactive protein (CRP), fibrinogen, lipids, and markers of visceral adiposity (MVA) were measured before and after treatment. There were no significant changes in homocysteine, leptin, fibrinogen and CRP concentrations in neither group. In OSAS and IHD no change in serum lipids and MVA were found. In pure OSAS group total cholesterol and LDL cholesterol concentrations significantly decreased (202.5 ± 38.5 mg/dl v. 186.7 ± 33.5 mg/dl, p = 0.001 and 127.3 ± 32.9 mg/dl v. 116.4 ± 26.9 mg/dl, p = 0.02, respectively). Triglycerides did not significantly change (p = 0.09). There were no significant changes in BMI (30.4 ± 3.8 v. 30.6 ± 3.6, p = 0.5), waist circumference (108.5 ± 8.0 cm v. 107.0 ± 7.5 cm, p = 0.09) and waist to hip ratio (1.03 ± 0.04 v. 1.01 ± 0.03, p = 0.07). Three month CPAP therapy did not change homocysteine and leptin concentration in neither group. However, it significantly decreased serum lipids concentration in patients with pure OSAS, but not in patients with OSAS and IHD, suggesting beneficial effects of CPAP therapy on cardiovascular risk factors.

To investigate the role of IL-18 in the obstructive sleep apnea syndrome (OSAS)-induced preeclampsia (PE), by comparison of the changes of serum IL-18 levels among different groups as well as before and after continuous positive airway pressure (CPAP) treatment in pregnant women with both OSAS and PE. In control group there were 18 normal pregnant women with apnea hypopnea index (AHI) < 5. In simple PE group 18 pregnant PE patients with an AHI < 5 were recruited. In PE plus OSAS group 16 PE patients with coexisting OSAS were collected. CPAP treatment was performed for 1 week in 6 patients with AHI > 15 from PE plus OSAS group.Serum IL-18 levels were measured with ELISA. There was a significant difference in serum IL-18 levels among control group [(261 ± 95) ng/L], simple PE group [(382 ± 121) ng/L], and PE plus OSAS group [(601 ± 89) ng/L, all P < 0.001]. Following CPAP treatment, there was a significant decrease in AHI, systolic blood pressures, and serum IL-18 levels, but a significant increase in minimal SpO₂ (P < 0.01). Our study demonstrated that serum IL-18 levels in PE patients with OSAS were significantly elevated, which suggested that OSAS might increase the incidence of PE by enhancing inflammatory response, while CPAP treatment could effectively improve the pathological process.