Adherence to CPAP Treatment and the Risk of Recurrent Cardiovascular Events: A Meta-Analysis.

Importance: The effect of continuous positive airway pressure (CPAP) on secondary cardiovascular disease prevention is highly debated. Objective: To assess the effect of CPAP treatment for obstructive sleep apnea (OSA) on the risk of adverse cardiovascular events in randomized clinical trials. Data Sources: PubMed (MEDLINE), EMBASE, Current Controlled Trials: metaRegister of Controlled Trials, ISRCTN Registry, European Union clinical trials database, CENTRAL (Cochrane Central Register of Controlled Trials), and ClinicalTrials.gov databases were systematically searched through June 22, 2023. Study Selection: For qualitative and individual participant data (IPD) meta-analysis, randomized clinical trials addressing the therapeutic effect of CPAP on cardiovascular outcomes and mortality in adults with cardiovascular disease and OSA were included. Data Extraction and Synthesis: Two reviewers independently screened records, evaluated potentially eligible primary studies in full text, extracted data, and cross-checked errors. IPD were requested from authors of the selected studies (SAVE [NCT00738179], ISAACC [NCT01335087], and RICCADSA [NCT00519597]). Main Outcomes and Measures: One-stage and 2-stage IPD meta-analyses were completed to estimate the effect of CPAP treatment on risk of recurrent major adverse cardiac and cerebrovascular events (MACCEs) using mixed-effect Cox regression models. Additionally, an on-treatment analysis with marginal structural Cox models using inverse probability of treatment weighting was fitted to assess the effect of good adherence to CPAP (≥4 hours per day). Results: A total of 4186 individual participants were evaluated (82.1% men; mean [SD] body mass index, 28.9 [4.5]; mean [SD] age, 61.2 [8.7] years; mean [SD] apnea-hypopnea index, 31.2 [17] events per hour; 71% with hypertension; 50.1% receiving CPAP [mean {SD} adherence, 3.1 {2.4} hours per day]; 49.9% not receiving CPAP [usual care], mean [SD] follow-up, 3.25 [1.8] years). The main outcome was defined as the first MACCE, which was similar for the CPAP and no CPAP groups (hazard ratio, 1.01 [95% CI, 0.87-1.17]). However, an on-treatment analysis by marginal structural model revealed a reduced risk of MACCEs associated with good adherence to CPAP (hazard ratio, 0.69 [95% CI, 0.52-0.92]). Conclusions and Relevance: Adherence to CPAP was associated with a reduced MACCE recurrence risk, suggesting that treatment adherence is a key factor in secondary cardiovascular prevention in patients with OSA.

Pulse Wave Amplitude Drops Index: A Biomarker of Cardiovascular Risk in Obstructive Sleep Apnea.

Rationale: It is currently unclear which patients with obstructive sleep apnea (OSA) are at increased cardiovascular risk. Objective: To investigate the value of pulse wave amplitude drops (PWADs), reflecting sympathetic activations and vasoreactivity, as a biomarker of cardiovascular risk in OSA. Methods: PWADs were derived from pulse oximetry-based photoplethysmography signals in three prospective cohorts: HypnoLaus (N = 1,941), the Pays-de-la-Loire Sleep Cohort (PLSC; N = 6,367), and "Impact of Sleep Apnea syndrome in the evolution of Acute Coronary syndrome. Effect of intervention with CPAP" (ISAACC) (N = 692). The PWAD index was the number of PWADs (>30%) per hour during sleep. All participants were divided into subgroups according to the presence or absence of OSA (defined as ⩾15 or more events per hour or <15/h, respectively, on the apnea-hypopnea index) and the median PWAD index. Primary outcome was the incidence of composite cardiovascular events. Measurements and Main Results: Using Cox models adjusted for cardiovascular risk factors (hazard ratio; HR [95% confidence interval]), patients with a low PWAD index and OSA had a higher incidence of cardiovascular events compared with the high-PWAD and OSA group and those without OSA in the HypnoLaus cohort (HR, 2.16 [1.07-4.34], P = 0.031; and 2.35 [1.12-4.93], P = 0.024) and in the PLSC (1.36 [1.13-1.63], P = 0.001; and 1.44 [1.06-1.94], P = 0.019), respectively. In the ISAACC cohort, the low-PWAD and OSA untreated group had a higher cardiovascular event recurrence rate than that of the no-OSA group (2.03 [1.08-3.81], P = 0.028). In the PLSC and HypnoLaus cohorts, every increase of 10 events per hour in the continuous PWAD index was negatively associated with incident cardiovascular events exclusively in patients with OSA (HR, 0.85 [0.73-0.99], P = 0.031; and HR, 0.91 [0.86-0.96], P < 0.001, respectively). This association was not significant in the no-OSA group and the ISAACC cohort. Conclusions: In patients with OSA, a low PWAD index reflecting poor autonomic and vascular reactivity was independently associated with a higher cardiovascular risk.

Respiratory Polygraphy Patterns and Risk of Recurrent Cardiovascular Events in Patients With Acute Coronary Syndrome.

Introduction: Obstructive sleep apnea (OSA) severity is based on the apnea-hypopnea index (AHI). The AHI is a simplistic measure that is inadequate for capturing disease severity and its consequences in cardiovascular diseases (CVDs). Deleterious effects of OSA have been suggested to influence the prognosis of specific endotypes of patients with acute coronary syndrome (ACS). We aim to identify respiratory polygraphy (RP) patterns that contribute to identifying the risk of recurrent cardiovascular events in patients with ACS. Methods: Post hoc analysis of the ISAACC study, including 723 patients admitted for a first ACS (NCT01335087) in which RP was performed. To identify specific RP patterns, a principal component analysis (PCA) was performed using six RP parameters: AHI, oxygen desaturation index, mean and minimum oxygen saturation (SaO2), average duration of events and percentage of time with SaO2 < 90%. An independent HypnoLaus population-based cohort was used to validate the RP components. Results: From the ISAACC study, PCA showed that two RP components accounted for 70% of the variance in the RP data. These components were validated in the HypnoLaus cohort, with two similar RP components that explained 71.3% of the variance in the RP data. The first component (component 1) was mainly characterized by low mean SaO2 and obstructive respiratory events with severe desaturation, and the second component (component 2) was characterized by high mean SaO2 and long-duration obstructive respiratory events without severe desaturation. In the ISAACC cohort, component 2 was associated with an increased risk of recurrent cardiovascular events in the third tertile with an adjusted hazard ratio (95% CI) of 2.44 (1.07 to 5.56; p-value = 0.03) compared to first tertile. For component 1, no significant association was found for the risk of recurrent cardiovascular events. Conclusion: A RP component, mainly characterized by intermittent hypoxemia, is associated with a high risk of recurrent cardiovascular events in patients without previous CVD who have suffered a first ACS.

Long-Term Effect of Obstructive Sleep Apnea and Continuous Positive Airway Pressure Treatment on Blood Pressure in Patients with Acute Coronary Syndrome: A Clinical Trial.

Rationale: Obstructive sleep apnea (OSA) is prevalent in patients with acute coronary syndrome (ACS) and is a cause of secondary hypertension. Objectives: To explore the long-term effects of OSA and continuous positive airway pressure (CPAP) treatment on blood pressure (BP) in patients with ACS. Methods: Post hoc analysis of the ISAACC study (Continuous Positive Airway Pressure in Patients with Acute Coronary Syndrome and Obstructive Sleep Apnea; NCT01335087) included 1,803 patients admitted for ACS. Patients with OSA (apnea-hypopnea index [AHI], ⩾15 events/h) were randomly assigned to receive either CPAP or usual care and were seen in follow-up for 1-5 years. Office BP was determined at each visit. Results: We included 596 patients without OSA, 978 patients in the usual care or poor CPAP adherence group, and 229 patients in the good CPAP adherence group. At baseline, 52% of the patients were diagnosed with hypertension. Median (25th to 75th percentile) age and body mass index were 59 (52.0 to 67.0) years and 28.2 (25.6 to 31.2) kg/m2, respectively. After a median (25th to 75th percentile) follow-up of 41.2 (18.3 to 59.6) months, BP changes were similar in the OSA and non-OSA groups. However, we observed an increase in BP in the third tertile of the AHI (AHI, >40 events/h), with a maximum difference in mean BP of +3.3 mm Hg at 30 months. Patients with OSA with good CPAP adherence (⩾4 h/night) reduced mean BP after 18 months compared with patients with usual care/poor CPAP adherence, with a maximum mean difference (95% confidence interval) of -4.7 (-6.7 to -2.7) mm Hg. In patients with severe OSA, we observed a maximum mean difference of -7.1 (-10.3 to -3.8) mm Hg. Conclusions: In patients with ACS, severe OSA is associated with a long-term increase in BP, which is reduced by good CPAP adherence. Clinical trial registered with www.clinicaltrials.gov (NCT01335087).

Canonical Pathways Associated with Blood Pressure Response to Sleep Apnea Treatment: A Post Hoc Analysis.

BACKGROUND: Several studies have reported an association between microRNAs (miRNAs) and hypertension or cardiovascular disease (CVD). In a previous study performed on a group of 38 patients, we observed a cluster of 3 miRNAs (miR-378a-3p, miR-100-5p, and miR-486-5p) that were functionally associated with the cardiovascular system that predicted a favorable blood pressure (BP) response to continuous positive airway pressure (CPAP) treatment in patients with resistant hypertension (RH) and obstructive sleep apnea (OSA) (HIPARCO score). However, little is known regarding the molecular mechanisms underlying this phenomenon. OBJECTIVES: The aim of the study was to perform a post hoc analysis to investigate the genes, functions, and pathways related to the previously found HIPARCO score miRNAs. METHODS: We performed an enrichment analysis using Ingenuity pathway analysis. The genes potentially associated with the miRNAs were filtered based on their confidence level. Particularly for CVD, only the genes regulated by at least 2 of the miRNAs were studied. RESULTS: We observed that the miRNAs studied regulate 200-249 molecules associated with several functions and diseases, including extracranial solid tumors and abdominal neoplasms, among others. The cardiac hypertrophy and NF-kB signaling pathways were identified as the cardiovascular pathways most influenced by these 3 miRNAs. CONCLUSIONS: The mechanisms by which CPAP treatment decreases the BP in OSA patients with RH could be related to the cardiac hypertrophy and NF-kB signaling pathways. Further investigations will be necessary to confirm these findings, contributing to the elucidation of new therapeutic targets in patients who do not respond to CPAP treatment.

The Effect of Sleep Apnea on Cardiovascular Events in Different Acute Coronary Syndrome Phenotypes.

Rationale: Obstructive sleep apnea (OSA) is associated with increased cardiovascular disease (CVD) risk. Conversely, OSA has not been shown to increase recurrent cardiovascular events in patients with acute coronary syndrome (ACS). This lack of homogeneity could suggest that the deleterious effect of OSA and its contribution to CVD could depend on specific patient profiles.Objectives: To evaluate the effect of OSA on cardiovascular risk for patients with different ACS phenotypes.Methods:Post hoc analysis of the ISAACC (Continuous Positive Airway Pressure in Patients with ACS and OSA) study, including 1,701 patients admitted for ACS (NCT01335087). To evaluate the presence of OSA (apnea-hypopnea index ≥ 15 events · h-1), all patients underwent polygraphy. Patients were followed up for a minimum period of 1 year. We performed nonsupervised clustering using latent class analysis to identify subgroups of patients on the basis of 12 clinical factors associated with cardiovascular risk. The effect of OSA on recurrent cardiovascular event risk was evaluated for each phenotype identified.Measurements and Main Results: Two phenotypes were identified: patients without previous heart disease and without previous ACS ("no-previous-CVD" phenotype; 81%) and patients with previous heart disease and previous ACS ("previous-CVD" phenotype; 19%). The median (interquartile range) at follow-up was 2.67 (3.8) years. For the no-previous-CVD phenotype, the effect of OSA showed an adjusted hazard ratio (95% confidence interval) of 1.54 (1.06-2.24; P value = 0.02), whereas for the previous-CVD phenotype, the effect of OSA showed an adjusted hazard ratio of 0.69 (0.46-1.04; P value = 0.08).Conclusions: For patients with ACS and a specific phenotype, OSA is associated with an increased risk of recurrent cardiovascular events. These patients are mainly characterized by no previous heart disease and admission for a first ACS occurrence.

Effect of obstructive sleep apnoea and its treatment with continuous positive airway pressure on the prevalence of cardiovascular events in patients with acute coronary syndrome (ISAACC study): a randomised controlled trial.

BACKGROUND: Despite the improvement in the prognosis of acute coronary syndrome (ACS), substantial morbidity and mortality remain. We aimed to evaluate the effect of obstructive sleep apnoea (OSA) and its treatment with continuous positive airway pressure (CPAP) on the clinical evolution of patients with ACS. METHODS: We designed a multicentre, open-label, parallel-group, randomised controlled trial of patients with ACS at 15 hospitals in Spain. Eligible non-sleepy patients were men and women aged 18 years and older, admitted to hospital for documented symptoms of ACS. All patients underwent respiratory polygraphy during the first 24-72 h after admission. OSA patients were randomly assigned (1:1) to CPAP treatment plus usual care (CPAP group) or usual care alone (UC group) by a computerised system available 24 h a day. A group of patients with ACS but without OSA was also included as a reference group. Because of the nature of the intervention, the trial intervention could not be masked to either investigators or patients. Patients were monitored and followed for a minimum of 1 year. Patients were examined at the time of inclusion; after 1 month, 3 months, 6 months, 12 months, 18 months, 24 months, 30 months, and 36 months; and every 12 months thereafter, if applicable, during the follow-up period. The primary endpoint was the prevalence of a composite of cardiovascular events (cardiovascular death or non-fatal events [Acute myocardial infarction, non-fatal stroke, hospital admission for heart failure, and new hospitalisations for unstable angina or transient ischaemic attack]) in patients followed up for a minimum of 1 year. The primary analysis was done according to the intention-to-treat principle. This study is registered with Clinicaltrials.gov, NCT01335087 and is now closed. FINDINGS: Between April 25, 2011, and Feb 2, 2018, a total of 2834 patients with ACS had respiratory polygraphy, of whom 2551 (90·01%) were recruited. 1264 (49·55%) patients had OSA and were randomly assigned to the CPAP group (n=633) or the UC group (n=631). 1287 (50·45%) patients did not have OSA, of whom 603 (46·85%) were randomly assigned to the reference group. Patients were followed up for a median of 3·35 years (IQR 1·50-5·31). The prevalence of cardiovascular events was similar in the CPAP and UC groups (98 events [16%] vs 108 events [17%]; hazard ratio [HR] 0·89 [95% CI 0·68-1·17]; p=0·40) during follow-up. Mean time of adherence to CPAP treatment was 2·78 h/night (SD 2·73). The prevalence of cardiovascular events was similar between patients in the reference group (90 [15%] events) and those in the UC group (102 (17%) events) during follow-up (1·01 [0·76-1·35]; p=0·93). The prevalence of cardiovascular events seem not to be related to CPAP compliance or OSA severity. 464 (74%) of 629 patients in the CPAP group had 1538 serious adverse events and 406 (65%) of 626 patients in the UC group had 1764 serious adverse events. INTERPRETATION: Among non-sleepy patients with ACS, the presence of OSA was not associated with an increased prevalence of cardiovascular events and treatment with CPAP did not significantly reduce this prevalence. FUNDING: ResMed (Australia), Fondo de Investigación Sanitaria (Fondo Europeo de Desarrollo Regional), the Spanish Respiratory Society, the Catalonian Cardiology Society, Esteve-Teijin, Oxigen Salud, and ALLER.

Biomarker panel in sleep apnea patients after an acute coronary event.

BACKGROUND: Acute coronary syndrome (ACS) is a major cause of death and closely related with obstructive sleep apnea (OSA). Our hypothesis is that several cardiovascular-related biomarkers could have a differential prognostic value for ACS severity in patients with OSA, and could also help (individually or combined) in the detection of OSA in patients after a coronary event. METHODS: Up to 361 consecutive individuals admitted due to ACS were included in the study. All of them were evaluated for ACS severity (Killip score, number of diseased vessels, ejection fraction) and further classified as OSA or non-OSA. Medical records were registered and eleven blood biomarkers were measured, including heart-type fatty acid-binding globulin, N-terminal pro-brain natriuretic peptide, matrix metalloproteinase-9 (MMP9), placental growth factor (PlGF) and high-sensitivity C-reactive protein. Odds ratios of every biomarker for ACS severity-related parameters were calculated and adjusted for age, gender, body-mass index (BMI), hypertension, diabetes, smoking and drinking. The use of clinical measures and biomarkers for the diagnosis of OSA in ACS patients was evaluated both alone and combined using ROC curves. RESULTS: Several biomarkers showed a significant association with ACS severity, which remained after adjusting for OSA and other potentially confounding variables. The mathematical combination of age, BMI, PlGF and MMP9 showed an area under the ROC curve (AUC) for OSA identification of 0.741, which was greater than any individual parameter or combination assessed: AUC(BMI):0.687, AUC(age):0.576, AUC(PlGF):0.584, AUC(MMP9):0.555. CONCLUSIONS: The usefulness of biomarkers in the assessment of ACS severity was independent of OSA and the other variables evaluated. In patients admitted after a coronary event, the combination of clinical measures and biomarkers showed a significant discriminating power for the detection of OSA. CLINICAL TRIAL REGISTRATION: NCT01335087 (clinicaltrials.gov).

Lung function impairment is not associated with the severity of acute coronary syndrome but is associated with a shorter stay in the coronary care unit.

BACKGROUND: Previous population-based studies have suggested that lung function impairment (LFI) could be associated with an increase in the mortality of cardiovascular events. METHODS: We evaluated the association between LFI and the severity and short-term prognosis of acute coronary syndrome (ACS). LFI was established through presence of a forced expiratory volume in one second (FEV1) and/or a forced vital capacity (FVC) less than 80% of predicted. RESULTS: Seventy-one LFI subjects (61.45±10.70 years, 83.10% males) and 247 non-LFI subjects (58.98±11.18 years, 80.57% males) with ACS were included. Subjects with LFI exhibited a higher prevalence of systemic hypertension (57.75% vs. 40.89%, P=0.02) and tobacco exposure (28.50±26.67 vs. 18.21±19.83 pack-years, P=0.007). No significant differences between groups were found regarding the severity of ACS (ejection fraction, Killip class, number of affected vessels, and peak plasma troponin). However, in comparison to non-LFI subjects, a significantly shorter length of stay in the coronary care unit (CCU) was observed in the LFI group (1.83±1.10 vs. 2.24±1.21 days, P=0.01) and this was even shorter in subjects with obstructive LFI (1.62±1.17 days, P=0.009). When considering obstructive sleep apnea (OSA), an interaction with length of stay was found, revealing that OSA subjects with obstructive LFI had the shortest length of stay in the CCU (0.60±0.89 days, P=0.05) also in comparison to non-LFI. CONCLUSIONS: This study indicates a possible association between LFI and a shorter length of stay in the CCU but does not show a significant association with ACS severity.

Sleep-Disordered Breathing Is Independently Associated With Increased Aggressiveness of Cutaneous Melanoma: A Multicenter Observational Study in 443 Patients.

BACKGROUND: Sleep-disordered breathing (SDB) has been associated with a greater incidence and mortality of cancer, although such findings are inconsistent. However, no large studies are currently available to investigate this association in patients with a specific type of cancer. This study seeks to assess potential relationships between SDB severity and aggressiveness markers of cutaneous melanoma. METHODS: Four hundred and forty-three patients with a diagnosis of melanoma underwent a sleep study within 6 months of diagnosis. General demographics were collected, along with melanoma characteristics and polygraphic parameters consisting of the apnea-hypopnea index (AHI) and indices of both continuous and intermittent night-time oxyhemoglobin desaturation (DI4%). An exploration of independent relationships between SDB and various objective melanoma aggressiveness markers (Breslow index, presence of ulceration, presence of regression, mitotic index, stage of severity, damage to the sentinel lymph, and spreading of the melanoma) was performed. RESULTS: Patients in the upper tertiles of AHI or DI4% were 1.94 (95% CI, 1.14-3.32; P = .022) and 1.93 (95% CI, 1.14-3.26; P = .013) times more likely, respectively, to present with aggressive melanoma (Breslow index > 1 mm) than those in the lowest tertiles of these sleep attributes after adjustment for age, sex, tumor location, and BMI. This association was particularly prominent among patients < 56 years of age with Breslow index > 2 mm. The presence of the additional markers of aggressiveness was also associated with higher AHI and DI4% values. CONCLUSIONS: The severity of SDB was independently associated with greater aggressiveness of cutaneous melanoma, particularly among younger patients.

Intermittent Hypoxia Is Associated With High Hypoxia Inducible Factor-1α but Not High Vascular Endothelial Growth Factor Cell Expression in Tumors of Cutaneous Melanoma Patients.

Epidemiological associations linking between obstructive sleep apnea and poorer solid malignant tumor outcomes have recently emerged. Putative pathways proposed to explain that these associations have included enhanced hypoxia inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF) cell expression in the tumor and altered immune functions via intermittent hypoxia (IH). Here, we examined relationships between HIF-1α and VEGF expression and nocturnal IH in cutaneous melanoma (CM) tumor samples. Prospectively recruited patients with CM tumor samples were included and underwent overnight polygraphy. General clinical features, apnea-hypopnea index (AHI), desaturation index (DI4%), and CM characteristics were recorded. Histochemical assessments of VEGF and HIF-1α were performed, and the percentage of positive cells (0, <25, 25-50, 51-75, >75%) was blindly tabulated for VEGF expression, and as 0, 0-5.9, 6.0-10.0, >10.0% for HIF-1α expression, respectively. Cases with HIF-1α expression >6% (high expression) were compared with those <6%, and VEGF expression >75% of cells was compared with those with <75%. 376 patients were included. High expression of VEGF and HIF-1α were seen in 88.8 and 4.2% of samples, respectively. High expression of VEGF was only associated with increasing age. However, high expression of HIF-1α was significantly associated with age, Breslow index, AHI, and DI4%. Logistic regression showed that DI4% [OR 1.03 (95% CI: 1.01-1.06)] and Breslow index [OR 1.28 (95% CI: 1.18-1.46)], but not AHI, remained independently associated with the presence of high HIF-1α expression. Thus, IH emerges as an independent risk factor for higher HIF-1α expression in CM tumors and is inferentially linked to worse clinical CM prognostic indicators.

Predictors of CPAP compliance in different clinical settings: primary care versus sleep unit.

BACKGROUND: Good adherence to continuous positive airway pressure (CPAP) treatment improves the patient's quality of life and decreases the risk of cardiovascular disease. Previous studies that have analyzed the adherence to CPAP were performed in a sleep unit (SU) setting. The involvement of primary care (PC) in the management of obstructive sleep apnea (OSA) patients receiving CPAP treatment could introduce factors related to the adherence to treatment. OBJECTIVES: The objective was to compare the baseline predictors of CPAP compliance in SU and PC settings. METHODS: OSA patients treated with CPAP were followed for 6 months in SU or PC setting. We included baseline clinical and anthropometrical variables, the Epworth Sleep Scale (ESS) score, the quality of life index, and the Charlson index. A logistic regression was performed for each group to determine the CPAP compliance predictors. Discrimination and calibration were performed using the area under the curve and Hosmer-Lemeshow tests. RESULTS: We included 191 patients: 91 in the PC group and 100 in the SU group. In 74.9% of the patients, the compliance was ≥ 4 h per day, with 80% compliance in the SU setting and 69.2% compliance in the PC setting (p = 0.087). The predictors of CPAP compliance were different between SU and PC settings. Body mass index, ESS, and CPAP pressure were predictors in the SU setting, and ESS, gender, and waist circumference were predictors in the PC setting. CONCLUSIONS: The predictors of adequate CPAP compliance vary between SU and PC settings. Detecting compliance predictors could help in the planning of early interventions to improve CPAP adherence.

Cardiac Troponin Values in Patients With Acute Coronary Syndrome and Sleep Apnea: A Pilot Study.

BACKGROUND: An analysis of cardiac injury markers in patients with OSA who sustain an episode of acute coronary syndrome (ACS) may contribute to a better understanding of the interactions and impact of OSA in subjects with ACS. We compared peak cardiac troponin I (cTnI) levels in patients with OSA and patients without OSA who were admitted for ACS. METHODS: Blood samples were collected every 6 hours from the time of admission until two consecutive assays showed a downward trend in the cTnI assay. The highest value obtained defined the peak cTnI value, which provides an estimate of infarct size. RESULTS: We included 89 patients with OSA and 38 patients without OSA with an apnea-hypopnea index of a median of 32 (interquartile range [IQR], 20.8-46.6/h and 4.8 [IQR, 1.6-9.6]/h, respectively. The peak cTnI value was significantly higher in patients without OSA than in patients with OSA (median, 10.7 ng/mL [IQR, 1.78-40.1 ng/mL] vs 3.79 ng/mL [IQR, 0.37-24.3 ng/mL]; P = .04). The multivariable linear regression analysis of the relationship between peak cTnI value and patient group, age, sex, and type of ACS showed that the presence or absence of OSA significantly contributed to the peak cTnI level, which was 54% lower in patients with OSA than in those without OSA. CONCLUSIONS: The results of this study suggest that OSA has a protective effect in the context of myocardial infarction and that patients with OSA may experience less severe myocardial injury. The possible role of OSA in cardioprotection should be explored in future studies.

Blood pressure response to CPAP treatment in subjects with obstructive sleep apnoea: the predictive value of 24-h ambulatory blood pressure monitoring.

The reduction in blood pressure (BP) with continuous positive airway pressure (CPAP) is modest and highly variable. In this study, we identified the variables that predict BP response to CPAP.24-h ambulatory BP monitoring (ABPM), C-reactive protein (CRP), leptin, adiponectin and 24-h urinary catecholamine were measured before and after 6 months of CPAP in obstructive sleep apnoea (OSA) patients.Overall, 88 middle-aged, obese male patients with severe OSA (median apnoea-hypopnoea index 42 events·h-1) were included; 28.4% had hypertension. 62 patients finished the study, and 60 were analysed. The daytime diastolic BP (-2 mmHg) and norepinephrine (-109.5 nmol·day-1) were reduced after CPAP, but no changes in the 24-h BP, night-time BP, dopamine, epinephrine, CRP, leptin or adiponectin were detected. The nocturnal normotension was associated with an increased night-time-BP (+4 mmHg) after CPAP, whereas nocturnal hypertension was associated with a reduction of 24-h BP (-3 mmHg). A multivariate linear regression model showed differential night-time BP changes after CPAP. Specifically, low night-time heart rate (<68 bpm) and BP dipper profile were associated with increased night-time BP and new diagnosis of nocturnal hypertension.Our results suggest that nocturnal hypertension, circadian BP pattern and night-time heart rate could be clinical predictors of BP response to CPAP and support the usefulness of 24-h ABPM for OSA patients before treatment initiation. These results need to be confirmed in further studies.

A prospective multicenter cohort study of cutaneous melanoma: clinical staging and potential associations with HIF-1α and VEGF expressions.

Melanoma is a highly prevalent cancer that is associated with substantial mortality. Although clinical staging procedures can serve as relatively robust prognostic indicators, we aimed to determine whether assessments of the abundance of hypoxia inducible factor-1α (HIF-1α) or vascular endothelial growth factor (VEGF) in postexcisional melanoma tumor tissues may enable more accurate determination of tumor aggressiveness. We carried out a multicenter prospective study, in which we systematically evaluated 376 consecutive patients diagnosed with melanoma, and performed histochemical assessments for both HIF-1α and VEGF immunoreactivity in the tumor biopsies. Multivariate analyses showed that higher HIF-1α expression, but not high VEGF, were associated significantly and independently with increased tumor aggressiveness as derived from several well-established aggressiveness criteria. A limitation of this study was that this was a descriptive prospective study lacking a post-hoc verification arm. Thus, the presence of increased numbers of positively labeled HIF-1α cells in melanoma tumors may potentially serve as an indicator of tumor phenotype and prognosis, and accordingly guide therapy.

Cell Death Biomarkers and Obstructive Sleep Apnea: Implications in the Acute Coronary Syndrome.

Study Objectives: Nucleosomes and cell-free double-stranded DNA (dsDNA) have been suggested as promising biomarkers in cell death-related diseases, such as acute coronary syndrome (ACS). Currently, the impact of obstructive sleep apnea (OSA) in patients with ACS is unclear. Our aim was to evaluate the relationship between OSA, dsDNA, and nucleosomes and to assess their potential implication in the development of ACS. Methods: Up to 549 patients were included in the study and divided into four groups (145 ACS; 290 ACS + OSA; 62 OSA; 52 controls). All patients underwent a sleep study, and serum concentrations of dsDNA and nucleosomes were measured. Results: Nucleosome and dsDNA levels were higher in patients with OSA than in controls (nucleosomes: 1.47 ± 0.88 arbitary units [AU] vs. 1.00 ± 0.33 AU; p < .001, dsDNA: 315.6 ± 78.0 ng/mL vs. 282.6 ± 55.4 ng/mL; p = .007). In addition, both biomarker levels were higher in patients with ACS than in non-ACS, independently of the presence of OSA. Conclusions: Both nucleosomes and dsDNA are increased in patients with OSA and might be related with the high cardiovascular risk seen in these patients. The extensive cell lysis during a myocardial infarction seems to be the major contributor to the high biomarker levels, and OSA does not seem to be implicated in such elevation when this acute event occurs. Clinical trial registration: NCT01335087 (clinicaltrials.gov).

Predictors of obstructive sleep apnoea in patients admitted for acute coronary syndrome.

Identifying undiagnosed obstructive sleep apnoea (OSA) patients in cardiovascular clinics could improve their management. Aiming to build an OSA predictive model, a broad analysis of clinical variables was performed in a cohort of acute coronary syndrome (ACS) patients.Sociodemographic, anthropometric, life-style and pharmacological variables were recorded. Clinical measures included blood pressure, electrocardiography, echocardiography, blood count, troponin levels and a metabolic panel. OSA was diagnosed using respiratory polygraphy. Logistic regression models and classification and regression trees were used to create predictive models.A total of 978 patients were included (298 subjects with apnoea-hypopnoea index (AHI) <15 events·h-1 and 680 with AHI ≥15 events·h-1). Age, BMI, Epworth sleepiness scale, peak troponin levels and use of calcium antagonists were the main determinants of AHI ≥15 events·h-1 (C statistic 0.71; sensitivity 94%; specificity 24%). Age, BMI, blood triglycerides, peak troponin levels and Killip class ≥II were determinants of AHI ≥30 events·h-1 (C statistic of 0.67; sensitivity 31%; specificity 86%).Although a set of variables associated with OSA was identified, no model could successfully predict OSA in patients admitted for ACS. Given the high prevalence of OSA, the authors propose respiratory polygraphy as a to-be-explored strategy to identify OSA in ACS patients.