Severity of obstructive sleep apnea and extension of coronary artery disease

New Modifiable Risk Factors Influencing Coronary Artery Disease Severity

Cardiovascular diseases (CVDs) remain the leading cause of death worldwide with coronary artery disease (CAD) being the first culprit in this group. In terms of CAD, not only its presence but also its severity plays a role in the patient's treatment and prognosis. CAD complexity can be assessed with the indicator named the SYNTAX score (SS). A higher SS is associated with major adverse cardiovascular event (MACE) occurrence in short- and long-term observations. Hence, the risk factors affecting CAD severity based on SS results may help lower the risk among patients with already developed CAD to reduce their impact on coronary atherosclerosis progression. The well-established risk factors of CAD are consistent with those associated with the coronary plaque burden. However, recently, it was shown that new indicators exist, which we present in this paper, that significantly contribute to CAD complexity such as inflammatory parameters, C-reactive protein (CRP), ratios based on blood smear results, and uric acid. Moreover, microbiota alteration, vitamin D deficiency, and obstructive sleep apnea (OSA) also predicted CAD severity. However, sometimes, certain indicators were revealed as significant only in terms of chronic coronary syndromes (CCSs) or specific acute coronary syndromes (ACSs). Importantly, there is a need to apply the interdisciplinary and translational approach to the novel CAD severity risk assessment to maximize the impact of secondary prevention among patients at risk of coronary atherosclerosis progression.

Association between sleep apnea-specific hypoxic burden and severity of coronary artery disease

PURPOSE

Sleep apnea-specific hypoxic burden (SASHB) is a polysomnographic metric that comprehensively measures the degree of nocturnal desaturation caused by obstructive sleep apnea. This research was conducted to elucidate the relationship between SASHB and coronary artery disease (CAD) severity.

METHODS

We carried out a prospective study of hospitalized patients with CAD of unstable angina who were expected to undergo invasive coronary angiography at Beijing Anzhen Hospital from February to September 2023. SASHB values were calculated using a self-programmed C +  + program. Multivariable logistic regression analysis was applied to identify the association between SASHB and the prevalence of severe CAD, documented by the Gensini Score, and the SYNTAX (Synergy between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery) Score.

RESULTS

This study enrolled 137 patients with a median age of 59 years, 96 (70.1%) of whom were male. A total of 125 (91.2%) patients had coronary stenosis of ≥ 50% in at least one location. Patients with a high SASHB of ≥ 18% min/h had a significantly higher Gensini Score (32.0 vs. 18.5, P = 0.002) and SYNTAX Score (14.0 vs. 7.0, P = 0.002) than those with a low SASHB. After adjusting for multiple covariates, a high SASHB was significantly associated with the prevalence of severe CAD, determined by a Gensini Score ≥ 21 (OR 2.67, P = 0.008) or a SYNTAX Score > 22 (OR 4.03, P = 0.016).

CONCLUSION

Our findings revealed a robust and independent association between SASHB and CAD severity in patients with unstable angina, highlighting the potential value of SASHB as a predictor of risk and a target for interventions aimed at preventing cardiovascular diseases.

TRIAL REGISTRATION

Chinese Clinical Trial Registry No. ChiCTR2300067991 on February 2, 2023.

Influence of obstructive sleep apnoea on coronary artery disease in a Chinese population

OBJECTIVE

This study aimed to investigate the correlation between obstructive sleep apnoea (OSA) and the severity of coronary artery disease (CAD) assessed by angiography.

METHODS

This prospective study screened 273 patients diagnosed with CAD by coronary angiography. The severity of CAD was assessed by SYNTAX score. A total of 255 subjects were enrolled of whom 161 were diagnosed with OSA, with an apnoea-hypopnoea index ≥5/hour. Ninety-four CAD patients without OSA were used as controls. The relationship between OSA and CAD was analysed by multiple linear regression.

RESULTS

The prevalence of OSA in CAD patients was 63.1%. The prevalences of single-vessel, two-vessel, and three-vessel disease were similar in the two groups. However, CAD was significantly more severe in patients with OSA, measured by SYNTAX score, than in those without OSA. OSA was independently associated with CAD after adjusting for traditional risk factors.

CONCLUSIONS

OSA is relatively common among patients with CAD in China. The independent association between OSA and CAD, even after adjusting for traditional confounders, suggests that OSA should be taken into account when considering the risk factors for CAD. The present findings highlight the important adverse influence of OSA on the severity of CAD.

Serum uric acid and arterial lactate levels in patients with obstructive sleep apnea syndrome: the effect of CPAP treatment

Objectives: Serum uric acid (UA) and arterial lactate acid (LA) are markers of oxidative stress and tissue hypoxia that are present in patients with obstructive sleep apnea syndrome (OSAS). The aim of the study was to evaluate the associations between UA and LA levels and OSAS characteristics as well as the effect of their levels after continuous positive airway pressure (CPAP) treatment.Methods: This is a retrospective of newly diagnosed patients with OSAS. UA and LA levels were measured the night before the diagnostic sleep study, and 6 months after CPAP therapy.Results: We evaluated 604 individuals with OSAS and 98 controls (i.e. individuals without sleep-related breathing disorders). Baseline median (IQR) serum UA levels were higher in OSAS patients compared to controls; 7.0 (6.4, 8.1) mg/dL vs 6.3 (6.1, 6.4) mg/dL, respectively (p < 0.001). This difference remained significant, after adjustment of serum UA to creatinine ratio (UA/Cr) (p < 0.001). Patients with OSAS had higher LA levels at baseline compared to controls; 2.26 (2.25, 2.31) mmol/L vs 1.90 (1.87, 1.97) mmol/L, respectively (p < 0.001). Both UA and LA levels decreased significantly after CPAP treatment [median (IQR): 7.0 (6.4, 8.1) mg/dL vs 6.4 (6.2, 6.8) mg/dL, p < 0.001 and 2.26 (2.25, 2.31) mmol/L vs 2.08 (2.07, 2.31) mmol/L, p < 0.001]. Several sleep parameters were independent predictors of UA and LA levels.Conclusion: In OSAS patients increased serum UA and arterial LA levels are found. CPAP therapy resulted in significant reductions in levels of both biomarkers.

Association between Obstructive Sleep Apnea and SYNTAX Score

Obstructive sleep apnea (OSA) is related to an increased risk of cardiovascular diseases, including coronary artery disease (CAD). We investigated the association between OSA and the severity of CAD by assessing coronary angiography findings. We retrospectively analyzed patients who underwent their first coronary angiography to evaluate CAD and polysomnography (PSG) to investigate the severity of OSA in our hospital from March 2002 to May 2015. The severity of CAD was determined based on coronary angiography findings using the SYNTAX score. The patients were divided into two groups according to the apnea-hypopnea index (AHI): mild OSA (AHI < 15/h) and moderate-to-severe OSA (AHI ≥ 15/h). Overall, 98 patients were enrolled. The SYNTAX score was significantly different between the two groups (p = 0.001). After adjustment for other risk factors, including age, sex, obesity, hypertension, hyperlipidemia, diabetes mellitus, smoking status, and family history of CAD, moderate-to-severe OSA significantly correlated to the SYNTAX score (partial correlations = 0.24, p = 0.039). These results suggest that the severity of CAD is related to moderate-to-severe OSA.

The differences of carotid atherosclerosis among non-OSAHS and OSAHS patients of different severities: a cross-sectional study

BACKGROUND

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a widely prevalent problem with many complications, such as hypertension and cerebral vascular diseases. Atherosclerosis, whose most severe outcome is ischemic stroke, is reported being affected by OSAHS. The objective of this article is to investigate the differences of carotid atherosclerosis patients with or without OSAHS by a cross-sectional research.

MATERIALS AND METHODS

Patients diagnosed with carotid atherosclerosis by ultrasonography were recruited. They were requested to fill the primary screening OSAHS questionnaire. Patients with high tendency of OSAHS underwent polysomnography (PSG) tests into OSAHS group, and patients without OSAHS were into non-OSAHS group. Blood tests and medical history were collected. Carotid atherosclerosis severity was analyzed by carotid artery intima-media thickness (IMT), carotid plaque, blood flow velocity, etc. Differences between the two groups and subgroups were analyzed.

RESULTS

A total of 242 carotid atherosclerosis patients were enrolled including 118 non-OSAHS patients (38 males and 80 females) and 124 OSAHS patients (40 mild, 32 moderate, and 52 severe). Significant differences were found in PSV-ICA and EDV-ICA on both sides (p < 0.05) but no significant differences on IMT and velocity of CCV. CA patients with OSAHS were younger than ones without OSAHS. With the severity of OSAHS increasing, the age of CA patients decreased. The more severity of OSAHS, the younger the patients were. There were no significant differences in comparing cholesterol, triglyceride, HDL, LDL, and glucose.

CONCLUSION

As far as CIMT, carotid plaque, blood flow velocity, and blood lipid are concerned, the severity of CA is not affected by the severity of OSAHS accordantly. The relationship between OSAHS and CA may not be dose dependent.

TRIAL REGISTRATION

This study has been registered on clinical trials (No. NCT03665818).

Cardiovascular Consequences of Obstructive Sleep Apnea

PURPOSE OF REVIEW

To review the clinical evidence for a relationship between obstructive sleep apnea and hypertension, arrhythmias, coronary artery disease, and congestive heart failure.

RECENT FINDINGS

Current data show that obstructive sleep apnea is a risk for cardiovascular disease. Studies have linked untreated moderate to severe obstructive sleep apnea to hypertension, cardiac arrhythmias, coronary artery disease, and congestive heart failure. However, uncertainty regarding benefits of treatment of obstructive sleep apnea to reduce the risk of cardiovascular disease still exists. The issue of poor compliance has been an on-going limitation of CPAP trials. Evidence shows obstructive sleep apnea is a risk factor for cardiovascular disease but trials have yet to clarify if cardiovascular disease morbidity and mortality decreases with treatment of the apnea. Future treatment trials are needed to address the question of whether treatment decreases cardiovascular risk in patients with obstructive sleep apnea.